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Publications recently added to the Pubs Warehouse

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Geology and assessment of undiscovered oil and gas resources of the Arctic Alaska Province, 2008

Released December 06, 2019 10:34 EST

2019, Professional Paper 1824-E

David W. Houseknecht, Kenneth J. Bird, Christopher Garrity

Thomas E. Moore, Donald L. Gautier, editor(s)

The Arctic Alaska Province encompasses all lands and adjacent continental shelf areas north of the Brooks Range-Herald Arch tectonic belts and south of the northern (outboard) margin of the Alaska rift shoulder. Even though only a small part is thoroughly explored, it is one of the most prolific petroleum provinces in North America, with total known resources (cumulative production plus proved reserves) of about 28 billion barrels of oil equivalent.

For assessment purposes, the province is divided into a platform assessment unit, comprising the Alaska rift shoulder and its relatively undeformed flanks, and a fold-and-thrust belt assessment unit, comprising the deformed area north of the Brooks Range and Herald Arch tectonic belts. Mean estimates of undiscovered, technically recoverable resources include nearly 28 billion barrels of oil and 122 trillion cubic feet of nonassociated gas in the platform assessment unit and 2 billion barrels of oil and 59 trillion cubic feet of nonassociated gas in the fold-and-thrust belt assessment unit.

Pesticide Mixtures in the Sacramento–San Joaquin Delta, 2016–17: Results from Year 2 of the Delta Regional Monitoring Program

Released December 06, 2019 10:03 EST

2019, Data Series 1120

Matthew De Parsia, Emily E. Woodward, James L. Orlando, Michelle L. Hladik

The Delta Regional Monitoring Program was developed by the Central Valley Regional Water Quality Control Board in response to the decline of pelagic fish species in the Sacramento–San Joaquin Delta that was observed in the early 2000s. The U.S. Geological Survey, in cooperation with the Delta Regional Monitoring Program, has been responsible for collecting and analyzing surface-water samples for a suite of 154 pesticides and pesticide degradates in surface water and in suspended sediment. Additional samples were collected for the analysis of dissolved organic carbon, dissolved copper, particulate organic carbon, particulate inorganic carbon, total particulate carbon, and total particulate nitrogen; and field water-quality indicators (water temperature, specific conductance, dissolved oxygen, pH, and turbidity) were measured at each site.

     Five integrator sites on streams draining mixed land-use watersheds were sampled monthly from July 2016 to June 2017. Two sites were sampled in the San Joaquin River watershed and one site was sampled in each of the Mokelumne River, Sacramento River, and Ulatis Creek watersheds.
     A total of 53 out of 154 pesticides (18 herbicides, 14 insecticides, 13 fungicides, 7 breakdown products, and 1 synergist) were detected in surface-water samples and 95 percent of samples contained mixtures of 2 or more pesticides. The most frequently detected pesticides were the herbicides hexazinone, metolachlor, and diuron (present in 83 percent, 72 percent, and 67 percent of water samples, respectively), the insecticide methoxyfenozide (present in 83 percent of samples), and the fungicides boscalid and azoxystrobin (present in 67 percent and 58 percent of samples, respectively). Pesticide concentrations detected in water samples ranged from below method detection limits to 1,300 nanograms per liter (ng/L) for the insecticide chlorantraniliprole. A total of 4 pesticides (2 herbicides and 2 insecticides) were detected in suspended-sediment samples and 13 percent of suspended-sediment samples contained at least 1 pesticide. Pesticide concentrations detected in suspended-sediment samples ranged from 4.1 to 750 ng/L, both for the herbicide pendimethalin.
     Six samples contained the insecticide imidacloprid at concentrations above the U.S. Environmental Protection Agency (EPA) Aquatic Life Benchmark (10 ng/L) for chronic toxicity to aquatic invertebrates. Three samples contained bifenthrin at concentrations above the EPA Aquatic Life Benchmark (1.3 ng/L) for chronic toxicity to invertebrates. One sample contained cyhalothrin at a concentration above the U.S. Aquatic Life Benchmark (3.5 ng/L) for acute toxicity to invertebrates.

User's guide for the national hydrography dataset plus (NHDPlus) high resolution

Released December 06, 2019 09:30 EST

2019, Open-File Report 2019-1096

Richard B. Moore, Lucinda D. McKay, Alan H. Rea, Timothy R. Bondelid, Curtis V. Price, Thomas G. Dewald, Craig M. Johnston

The National Hydrography Dataset Plus High Resolution (NHDPlus HR) is a scalable geospatial hydrography framework built from the High Resolution (1:24,000-scale or better) National Hydrography Dataset (NHD), nationally complete Watershed Boundary Dataset (WBD), and ⅓-arc-second (10-meter ground spacing) 3D Elevation Program (3DEP) digital elevation model (DEM) data. The NHDPlus HR brings modeling and assessment to a local neighborhood level while nesting seamlessly into the national context.

NHDPlus HR is modeled after the highly successful NHDPlus version 2 (NHDPlus V2). Like the NHDPlus V2, the NHDPlus HR includes data for a nationally seamless network of stream reaches, elevation-based catchment areas, flow surfaces, and value-added attributes that enhance stream-network navigation, analysis, and data display. Users will find that the NHDPlus HR, however, provides much greater detail. This User’s Guide is intended to provide necessary information and guidance in the use of NHDPlus HR data.

Flood-frequency comparison from 1995 to 2016 and trends in peak streamflow in Arkansas, water years 1930–2016

Released December 05, 2019 14:04 EST

2019, Scientific Investigations Report 2019-5131

Paul A. Ensminger, Brian K. Breaker

In 2016, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers and the Federal Emergency Management Agency, began a study in Arkansas to investigate possible increasing trends in annual peak streamflow data and the possible resulting increase in the annual exceedance probability flood (AEPF) predictions. Temporal trends of peak streamflow were investigated at 15 selected streamgages on unregulated streams in Arkansas having 30 or more years of peak streamflow data through the 2016 water year. For the period of record at each streamgage, the Mann-Kendall trend test indicated that 14 of the 15 streamgages had no statistically significant peak streamflow trends and 1 streamgage had a statistically significant decreasing peak streamflow trend. Visual examination of the locally estimated scatterplot smoothing technique trend lines of the peak streamflow data indicated a possible increasing peak streamflow trend at 8 of the 15 streamgages since the 1990s.

A sequential series analysis of the 1-percent AEPF at each of the 15 selected streamgages was completed by selecting an initial subset of the oldest peak streamflow data from each site to estimate the initial 1-percent AEPF. This initial peak streamflow data subset was subsequently appended with 10-year increments of additional peak streamflow data until the full period of peak streamflow data was analyzed. The maximum increase in the 1-percent AEPF was 113 percent, and the maximum decrease was 31.9 percent.

Percentage differences between the AEPFs derived from regional regression equations presented in the 1995 and 2016 Arkansas flood-frequency reports were compared. The average percentage differences for the 74 selected locations indicate that the 4-, 2-, 1-, and 0.2-percent AEPFs computed using the 2016 regional regression equations were higher by 3.52, 5.10, 8.59, and 13.31 percent, respectively (25-, 50-, 100-, and 500-year recurrence interval floods), than the same percentage AEPFs computed using the 1995 regional regression equations. The average percentage differences between the 1995 and 2016 AEPFs for the 10-percent AEPF (10-year recurrence interval flood) resulted in 2016 AEPF predictions being 0.41 percent higher. For the 50- and 20-percent AEPFs (2- and 5-year recurrence interval floods), the 2016 AEPFs were less than the 1995 AEPFs by 2.53 and 0.31 percent, respectively.

Hydrogeologic framework of the Virginia Eastern Shore

Released December 05, 2019 12:00 EST

2019, Scientific Investigations Report 2019-5093

E. Randolph McFarland, Todd A. Beach

The Yorktown-Eastover aquifer system of the Virginia Eastern Shore consists of upper, middle, and lower confined aquifers overlain by correspondingly named confining units and underlain by the Saint Marys confining unit. Miocene- to Pliocene-age marine-shelf sediments observed in 205 boreholes include medium- to coarse-grained sand and shells that compose the aquifers and fine-grained sand, silt, and clay that compose the confining units. The upper confining unit also includes fine-grained and organic-rich back-barrier and estuarine sediments of Pleistocene age. An overlying surficial aquifer is composed mostly of Pleistocene-age nearshore sand and gravel with smaller amounts of cobbles and boulders.

In addition, Pleistocene-age sediments that fill three buried paleochannels are for the first time explicitly delineated here as distinct hydrogeologic units. Two aquifers are composed of medium- to coarse-grained fluvial sand and gravel, and an intervening confining unit is composed of fine-grained estuarine sand, silt, clay, and organic material. Aquifer and confining-unit sediments are also mixed with reworked marine-shelf sediments eroded from the sides of the paleochannels.

Hydrogeologic units of the Yorktown-Eastover aquifer system generally dip eastward, are as much as several tens of feet thick, and have an undulating configuration possibly resulting from the underlying Chesapeake Bay impact crater. Aquifers and confining units are incised by the three paleochannels along an upward-widening and eastward-lengthening series of structural “windows.” Hydrogeologic units within mainstems and branching tributaries of the paleochannels dip southeastward parallel to slopes of the paleochannels, are as much as several tens of feet thick, and laterally abut the Yorktown-Eastover aquifer system along paleochannel sidewalls. The Yorktown-Eastover aquifer system is thereby hydraulically breached by the paleochannels to alternately create barriers to or conduits for groundwater flow.

Results of previously documented aquifer tests at 58 wells indicate that transmissivity is generally greatest in young, shallow, and coarse-grained nearshore and fluvial sediments of the surficial aquifer and paleochannels. Transmissivity progressively decreases with depth in older, deeper, and finer grained marine-shelf sediments of the Yorktown-Eastover aquifer system, probably because they have undergone compaction as a result of greater overburden pressure over longer periods of time.

Compiled chloride concentrations in samples from 330 wells generally increase downward, with most of the samples collected at altitudes above −300 feet and with most concentrations less than 250 milligrams per liter. The saltwater-transition zone has a broad trough-like shape aligned with the peninsula, being relatively shallow along the coastline and deeper along the central “spine.” Because movement of the saltwater is slow, the configuration largely reflects groundwater flow prior to widespread groundwater withdrawals. Fresh groundwater has leaked downward along deep parts of the saltwater-transition zone and leaked upward along shallower parts to discharge at the coast.

The saltwater-transition zone also exhibits an anomalous ridge across the center of the peninsula. Groundwater levels indicate that the saltwater ridge formed primarily by the Exmore paleochannel acting as a large lateral collector drain. Groundwater levels were lowered, and the position of saltwater-transition zone was elevated, by a flow conduit that intercepted groundwater that otherwise would have flowed toward and discharged along the coastline.

Nearly all freshwater on the Virginia Eastern Shore is supplied by groundwater withdrawals, which have lowered water levels, altered hydraulic gradients, and created a concern for saltwater intrusion. Previous characterizations of groundwater conditions that are relied on to manage groundwater development have been limited by a lack of hydrogeologic information, particularly data on buried paleochannels that are critical to safeguarding the groundwater supply. Using recently available expanded information, the U.S. Geological Survey undertook a study in cooperation with the Virginia Department of Environmental Quality during 2016–19 to develop an improved description of the groundwater system called a “hydrogeologic framework.”

The hydrogeologic framework can aid water-supply planning and development by providing information on broad trends in aquifer configurations, hydraulic properties, and proximity to saltwater to avoid chloride contamination. Digital models to evaluate effects of groundwater withdrawals can also be improved with expanded data and capabilities to evaluate paleochannel hydraulic connections and the potential for saltwater movement.

The hydrogeologic framework is limited by the nonuniform distribution of boreholes and the subjective delineation of aquifers and confining units, including those within paleochannels that are regarded as preliminary. The configuration of the saltwater-transition zone is also regarded as preliminary because of the nonuniform distribution of groundwater samples. Low well-sampling frequency precludes characterizing movement of the saltwater-transition zone. A monitoring strategy of sampling and possibly electromagnetic-induction well logging could be used to detect saltwater movement.

Glacier retreat in Glacier National Park, Montana

Released December 04, 2019 15:45 EST

2019, Fact Sheet 2019-3068

Caitlyn Florentine

Currently, the volume of land ice on Earth is decreasing, driving consequential changes to global sea level and local stream habitat. Glacier retreat in Glacier National Park, Montana, U.S.A., is one example of land ice loss and glacier change. The U.S. Geological Survey Benchmark Glacier Project conducts glaciological research and collects field measurements across select North American glaciers, including Sperry Glacier located in Glacier National Park. These records provide direct evidence of glacier change. The amount and timing of Earth’s land ice that will be lost in the future depends on the future trajectory of greenhouse gas emissions. Ongoing glaciological research will enhance physical understanding and forecasting capabilities; however, the continued retreat and ice mass loss of small glaciers in Glacier National Park is certain. 

Evaluation of stormwater treatment vault with Coanda-effect screen for removal of solids and phosphorus in urban runoff

Released December 04, 2019 15:37 EST

2019, Journal of Sustainable Water in the Built Environment (6)

Nicolas Buer, William R. Selbig

Catch basins commonly are used by cities as part of a stormwater management plan to remove sediment and associated contaminants from stormwater, keeping them in compliance with regulations. Recently, the city of Madison, Wisconsin modified traditional catch basins by incorporating a fine-mesh (1-mm) Coanda-effect screen into the design with the goal of increasing removal of sediment and organic matter from stormwater. The US Geological Survey (USGS), in cooperation with the City of Madison, installed a water-quality monitoring station at such a catch basin to quantify reductions in total suspended solids (TSS), volatile suspended solids (VSS), suspended sediment concentration (SSC), total phosphorus (TP), and dissolved phosphorus (DP) from urban stormwater before entering Lake Monona. A comparison of the cumulative load from 33 samples collected during the summers of 2016 and 2017 showed 23% and 45% reductions in TSS and SSC, respectively. A smaller reduction was observed for TP, 16%, whereas DP remained unchanged. Reported traditional catch basin sediment removal varies greatly, although typical removal rates are similar. Results from this study will help regulated municipalities determine whether the use of screened catch basins can help meet water-quality goals.

Environmental and biological factors influence migratory Sea Lamprey catchability: Implications for tracking abundance in the Laurentian Great Lakes

Released December 03, 2019 18:57 EST

2019, Journal of Fish and Wildlife Management

Sean A Lewandoski, Gale A Bravener, Peter J. Hrodey, Scott M. Miehls

Sea Lamprey Petromyzon marinus population trends in the Great Lakes are tracked by trapping migratory adults in tributaries and using mark and recapture techniques to estimate abundance. Understanding what environmental and biological factors influence Sea Lamprey capture in tributaries is crucial to developing efficient trapping methods and reliable abundance estimates. We analyzed data from trapping sites located on eight Great Lakes tributaries using Cormack-Jolly-Seber models and examined how water temperature, discharge, sex, and length influenced Sea Lamprey apparent survival and capture probability. Sea Lamprey apparent survival was negatively associated with water temperature in all tributaries. Additionally, the odds of small Sea Lamprey (≤45 cm) remaining available to capture were 39% less (95% CI: 63% decrease – 1% increase) than large (>45 cm) lamprey odds. These observed relationships were used to investigate if bias in abundance estimates using the pooled-Petersen estimator and Jolly-Seber models was expected to be similar across trapping locations or influenced by variable environmental conditions and biological traits. Pooled-Petersen abundance estimates had a positive bias when datasets were generated from simulated populations with empirical relationships between environmental characteristics and catchability. The degree of bias depended upon changes in stream warming patterns and was not consistent among trapping locations. Jolly-Seber models using data from either weekly-batch-marked or uniquely-marked individuals generated abundance estimate with low bias when data quality was high, but performed poorly in scenarios with few recaptured Sea Lamprey. This research can promote improved Sea Lamprey monitoring efforts by providing insight into the reliability of the pooled-Petersen abundance estimator as a tool for tracking Sea Lamprey populations and demonstrating the limitations of adopting more robust methods when data are sparse.

Assessment of continuous oil and gas resources in the Mississippian Delle Phosphatic Member of the Woodman Formation in the Eastern Great Basin Province of Nevada, Utah, and Idaho, 2019

Released December 03, 2019 12:00 EST

2019, Fact Sheet 2019-3062

Christopher J. Schenk, Tracey J. Mercier, Thomas M. Finn, Kristen R. Marra, Phuong A. Le, Michael E. Brownfield, Heidi M. Leathers-Miller

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 144 million barrels of shale oil and 559 billion cubic feet of shale gas in the Mississippian Delle Phosphatic Member of the Woodman Formation in the Eastern Great Basin Province of Nevada, Utah, and Idaho.

Lake trout spawning and habitat assessment at Stony Island Reef

Released December 03, 2019 10:22 EST

2018, Book chapter, NYSDEC Lake Ontario annual report 2018

Stacy Furgal, Brian F. Lantry, Brian C. Weidel, John M. Farrell, Dimitry Gorsky, Zy Biesinger

Lake trout stocking began in the 1970s as part of a binational effort to restore a self-sustaining population of lake trout in Lake Ontario. Despite 48 years of restoration stocking, lake trout in Lake Ontario have not reestablished a self-sustaining population. Spawning surveys done at Stony Island Reef (SIR) in eastern Lake Ontario in 1987 and 1989 documented lake trout egg deposition and swim-up fry. Bottom trawls in the early 1990s found naturally-reproduced juvenile lake trout in this region of the lake. More recently, naturally-reproduced juveniles have been found in western Lake Ontario, but few have been found near SIR in the eastern basin. In 2017 and 2018, we examined SIR spawning habitat and lake trout egg deposition rates and compared them to historical values. The average interstitial depth observed in 2018 was less than 4 cm, and the maximum depth observed was 15 cm. These interstitial depths are greatly reduced from depths up to 45 cm reported in the 1980s. Only one egg was captured in 95 egg nets deployed during the spawning period, which resulted in a CPUE of 0.00035 eggs/net/day, markedly lower than the egg densities measured at SIR in 1987 and 1989 of (1.27 eggs/net/day and 0.27 eggs/net/day respectively). Observations of the cobble spawning habitat suggested interstitial spaces were more infilled relative to conditions observed in the 1980s. Infill material was heavily comprised of dreissenid mussels shells and shell fragments. These findings indicate that changes in lake trout spawning habitat may be inhibiting lake trout reproduction at SIR.

Observations of the spawning ecology of the imperiled Clear Lake Hitch Lavinia exilicauda chi

Released December 02, 2019 15:08 EST

2019, California Fish and Game (105) 225-232

Frederick Feyrer

Migrations for the purposes of reproduction are widely documented across the animal kingdom and are particularly common in fishes and other aquatic organisms (Dingle 2014). One important migration strategy in fishes is potamodromy, which is the movement from one location to another entirely within freshwater (Morais and Daverat 2016). Thurow (2016) estimated that worldwide there are approximately 13,000 potamodromous fish species. Potamodromous species as a group are also relatively imperiled, owing to the loss or destruction of the diversity of habitats often required for successful reproduction and recruitment (Thurow 2016). The Clear Lake Hitch Lavinia exilicauda chi is an imperiled potamodromous cyprinid that is endemic to a single freshwater lake: Clear Lake, Lake County, California, USA. The species lives to approximately six years of age and attains a maximum size of approximately 350 mm fork length. As juveniles and adults, it feeds primarily on macroinvertebrates, including insects and zooplankton (Geary and Moyle 1980). Formerly highly abundant and a staple food for the Pomo tribes of the Clear Lake region, Clear Lake Hitch abundance is believed to have declined substantially from historical levels (California Department of Fish and Wildlife [CDFW] 2014). Presently, Clear Lake Hitch is listed as threatened under the California Endangered Species Act and has been petitioned for listing under the U.S. Endangered Species Act. The purpose of this paper is to document fortuitous observations of Clear Lake Hitch spawning and holding in stream habitat to generate baseline information that is needed to manage the species. The observations facilitated addressing the following questions (1) under what water temperature and flow conditions does spawning occur?, (2) what are the major habitat features where spawning takes place?, (3) what are the fundamental aspects of spawning behavior?, (4) what is the immediate fate of eggs deposited during spawning?, and (5) when not engaged in spawning, what type of stream habitat is used by Clear Lake Hitch and do they actively feed?

Reach-scale monitoring and modeling of rivers—Expanding hydraulic data collection beyond the cross section

Released December 02, 2019 14:19 EST

2019, Fact Sheet 2019-3073

Brandon T. Forbes, Claire E. Bunch, Geoffrey DeBenedetto, Corey J. Shaw, Bruce Gungle

For over 125 years, the U.S. Geological Survey streamgage network has provided important hydrologic information about rivers and streams throughout the Nation. Traditional streamgage methods provide reliable stage and streamflow data but typically only monitor stage at a single location in a river and require frequent calibration streamflow measurements. Direct measurements are not always feasible, therefore improved sensors and methods are being deployed at gages to better document streamflow conditions between measurements. The technology and techniques of reach-scale monitoring allow the U.S. Geological Survey to collect more data across the full range of streamflow without requiring that a hydrographer be present. The U.S. Geological Survey Arizona Water Science Center’s reach-scale monitoring program will enhance the Arizona streamgage network with more accurate streamflow measurements and provide more extensive streamflow records and geomorphological datasets for our agency partners and the public. Reach-scale monitoring installations and techniques are applicable to streams of the western United States and likely throughout the Nation.

Preliminary status of Lake Ontario Alewife based on the 2019 spring trawl survey

Released December 02, 2019 13:00 EST

2019, Report

Brian C. Weidel, Jeremy P. Holden, Michael J. Connerton

-The 2019 spring prey fish trawl survey was the most extensive fish survey ever conducted on Lake Ontario with 252 bottom trawls collecting 214,569 fish from 39 species, in main-lake and embayment habitats, at depths ranging from 5 to 225 meters (16.5 – 742.5 feet).

-Alewife distribution was similar in U.S. (southern) and Canadian (northern) portions of the lake, which differs from the previous three years of whole-lake surveys when Alewife in April were more abundant in either U.S. (2017) or Canadian (2016, 2018) waters.

-The 2019 lake-wide average biomass index for adult Alewife (Age2+) declined 29% relative to 2018.

-The lake-wide biomass index for Age-1 Alewife in 2019 (2.2 kg/ha) declined relative to 2018 (2.6 kg/ha) and was the lowest Age-1 biomass observed since whole-lake sampling began in 2016.

-The current biomass, size structure, and age structure of the adult Alewife population reflect the lower than-average Alewife reproductive success observed in the 2013- and 2014-year classes. 

-Reproductive success was also lower than average in 2017 and 2018, suggesting the adult Alewife biomass may continue to decline.

Asian swamp eels in North America linked to the live-food trade and prayer-release rituals

Released December 02, 2019 11:17 EST

2019, Aquatic Invasions (14) 775-814

Leo Nico, Jay V. Kilian, Andrew J. Ropicki, Matthew Harper

We provide a history of swamp eel (family Synbranchidae) introductions around the globe and report the first confirmed nonindigenous records of Amphipnous cuchia in the wild. The species, native to Asia, is documented from five sites in the USA: the Passaic River, New Jersey (2007), Lake Needwood, Maryland (2014), a stream in Pennsylvania (2015), the Tittabawassee River, Michigan (2017), and Meadow Lake, New York (2017). The international live-food trade constitutes the major introduction pathway, a conclusion based on: (1) United States Fish and Wildlife Service’s Law Enforcement Management Information System (LEMIS) database records revealing regular swamp eel imports from Asia since at least the mid-1990s; (2) surveys (2001–2018) documenting widespread distribution of live A. cuchia among ethnic food markets in the USA and Canada; (3) indications that food markets are the only source of live A. cuchia in North America; and (4) presence of live A. cuchia in markets close to introduction sites. Prayer release appears to be an important pathway component, whereby religious practitioners purchase live A. cuchia from markets and set them free. Prevalence of A. cuchia in US markets since 2001 indicates the species is the principal swamp eel imported, largely replacing members of the Asian complex Monopterus albus/javanensis. LEMIS records (July 1996–January 2017) document 972 shipments containing an estimated 832,897 live swamp eels entering the USA, although these data underestimate actual numbers due to undeclared and false reporting. LEMIS data reveal most imports originate in Bangladesh, Vietnam, and China. However, LEMIS wrongly identifies many imported swamp eels as “Monopterus albus”; none are identified as A. cuchia although specimens from Bangladesh and India are almost certainly this species. Some imported A. cuchia are erroneously declared on import forms as Anguilla bengalensis. To date, there is no evidence of A. cuchia reproduction in open waters of North America, presumably because it is a tropical-subtropical species and all introductions thus far have been in latitudes where winter water temperatures regularly fall near or below freezing.

A draft decision framework for the National Park Service Interior Region 5 bison stewardship strategy

Released December 02, 2019 06:49 EST

2019, Natural Resource Report 2019/204

Amy Symstad, Brian W. Miller, Tanya M Shenk, Nicole D Athearn, Michael C. Runge

The Department of the Interior Bison Conservation Initiative calls for its bureaus to plan and implement collaborative American bison conservation and to ensure involvement by tribal, state, and local governments and the public in that conservation. Four independently managed and geographically separated National Park Service (NPS) units in Interior Region 5 (IR5) preserve bison and other components of a formerly contiguous Great Plains landscape. Management of bison in IR5 parks has historically been specific to each park, and livestock and range management science informed much of the decision making. In the past two decades, NPS has shifted away from managing bison from this livestock-based perspective towards a wildlife stewardship approach, including ensuring their long-term adaptive potential and considering them as just one part of a complex ecosystem. This shift requires a more holistic and cooperative approach to stewardship that is challenging not only because of limitations in funding and fluctuations in leadership priorities, but also because of the constraints imposed by the parks’ relatively small, fenced areas. The IR5 NPS Bison Stewardship Strategy (“Strategy”) will help the NPS to meet its responsibilities in cooperative stewardship of bison. The Strategy will serve to organize and consolidate the NPS’s legal and policy responsibilities within a framework of collectively defined values and objectives to support the careful and transparent decision-making processes that both guide and transcend park-specific planning. This report describes a preliminary decision framework for the Strategy, including the context, the fundamental objectives, and a range of alternative strategies developed and considered through two workshops and a series of conference calls with NPS personnel, stakeholders, and outside experts with an interest in IR5 NPS bison stewardship. Although not the Strategy itself, this framework serves as the Strategy’s starting point and identifies 14 fundamental objectives, falling in four major themes: Persistence of Wild and Healthy Bison 1. Maximize the long-term persistence of bison in IR5 parks 2. Maximize the long-term adaptive capacity of bison in North America 3. Maximize the wildness of the bison herds 4. Maximize humane treatment of bison, while allowing natural processes to occur Supporting Tribal Buffalo Culture 5. Improve relationships, trust, and communication with Tribes to enhance shared stewardship of bison within and beyond IR5 6. Maximize the number of live, healthy bison that can be transferred to tribal herds Persistence of Native Ecological Communities and Processes 7. Maximize structural and compositional heterogeneity of native prairie plant communities across space and time within each park 8. Maximize the abundance and diversity of animal species of special concern 9. Minimize the loss of native grassland within each park 10. Minimize the abundance of exotic plants in the park landscape 11. Maximize riparian area and wetland integrity Public Outreach 12. Maximize the number of healthy, wild bison that are visible to the public 13. Maximize the safety of visitors 14. Maximize public understanding of the past, present, and future of bison and Native Americans in the Great Plains The terms “minimize” and “maximize” in these objectives describe the desired direction for each individual objective. Finding the right balance among these objectives and any others identified in further work is one of the central challenges in developing the Strategy. To that end, this report also demonstrates and describes potential methods for evaluating how well alternative strategies would achieve each of the fundamental objectives.

Aquatic cycling of mercury

Released December 01, 2019 17:13 EST

2019, Book chapter, Mercury and the Everglades. A synthesis and model for complex ecosystem restoration

William H. Orem, David P. Krabbenhoft, Brett Poulin, George A Aiken

This chapter examines crucial processes in the aquatic cycling of mercury (Hg) that may lead to microbial production of neurotoxic and bioaccumulative methylmercury (MeHg), and highlights environmental conditions in the Everglades that make it ideal for MeHg production and bioaccumulation. The role of complexation of Hg2+ in surface water, especially by dissolved organic matter (DOM), in the transport of mercury to sites of microbial methylation are discussed. Photochemical reactions important in Hg cycling in surface water are also discussed. A principal focus of the chapter is on the environmental conditions that promote MeHg production, especially the role of sulfide and DOM in transport of inorganic Hg into bacteria for methylation, and the types of bacteria that have the ability to methylate Hg. Finally, perturbations to the ecosystem (e.g., fire and drought) that have important effects on Hg cycling are discussed.

Sulfur contamination in the Everglades, a major control on mercury methylation

Released December 01, 2019 11:59 EST

2019, Book chapter, Mercury and the Everglades. A Synthesis and Model for Complex Ecosystem Restoration

William H. Orem, David P. Krabbenhoft, Brett Poulin, George Aiken

In this chapter sulfur contamination of the Everglades and its role as a major control on methylmercury (MeHg) production is examined. Sulfate concentrations over large portions of the Everglades (60% of the ecosystem) are elevated or greatly elevated compared to background conditions of <1 mg/L. Land and water management practices in south Florida are the primary reason for the high levels of sulfate loading to the Everglades. Marshes in the northern Everglades that are highly enriched in sulfate have average concentrations of 60 mg/L, but water in canals in the Everglades Agricultural Area (EAA) contain the highest concentrations of sulfate averaging 60–70 mg/L. Studies that examined the mass balance of sulfur to the Everglades have determined that the primary sources of sulfate include: sulfur currently used in agriculture, and natural and legacy agricultural sulfur released by oxidation of organic soil within the EAA. The extensive loading of sulfate to the ecosystem increases microbial sulfate reduction, the dominant microbial process driving mercury methylation and MeHg production. The biogeochemical processes linking sulfate loading and MeHg production, however, are complex. MeHg production increases as sulfate levels rise from levels <1 mg/L up to about 20 mg/L. However, production of sulfide (a byproduct of microbial sulfate reduction) starts to inhibit MeHg production above 20 mg/L. Sulfate loading to canals in the EAA has impacted the northern Everglades the most, but the Everglades canal system can transport sulfate as far as Everglades National Park (ENP), 80 km further south. Plans to deliver more water to ENP as part of restoration may increase overall sulfate loads to the southern Everglades.

Reduction of sulfate loading should be a major goal of Everglades restoration because of the many negative effects of sulfate on the ecosystem. The ecosystem has been shown to respond quickly to reductions in sulfate loading, and strategies for reducing sulfate loading may produce positive outcomes for the Everglades in the near-term. Strategies for reducing sulfate loading will need to include: best management practices for agricultural use of sulfate, approaches to minimize soil oxidation in the EAA, and modifications to stormwater treatment areas to improve sulfate retention.

Estimating market conditions for potential entry of new sources of anthropogenic CO2 for EOR in the Permian Basin

Released November 30, 2019 12:17 EST

2019, Conference Paper, U.S. Association for Energy Economics and International Association for Energy Economics North American Conference, 37th

Steven T. Anderson, Steven Cahan

This study attempts to determine feasible carbon dioxide (CO2) price thresholds for entry of new sources of anthropogenic (man-made) CO2 for utilization in enhanced oil recovery (EOR) in the Permian Basin. Much of the discussion about carbon capture, utilization, and storage (CCUS) has focused on the high costs of carbon capture as the major barrier to entry of new anthropogenic sources of CO2 for EOR. In addition, a recent study by Edwards and Celia (2018) suggests that the lack of a CO2 transportation network to efficiently transport CO2 from ethanol plants in the Midwest to EOR sites in the Permian Basin could be a prohibitive barrier to commercial-scale entry (without some Government assistance to help finance the construction of new CO2 pipelines), despite the costs of carbon capture from ethanol plants being relatively low. Thus, entry of additional sources of anthropogenic CO2 for use in EOR in the Permian Basin could be primarily by major carbon emitters that are located closest to the existing CO2 pipeline network that currently transports mostly natural CO2 (extracted from geologic reservoirs) to EOR sites. Data from the U.S. Environmental Protection Agency (EPA)’s Greenhouse Gas Reporting Program (GHGRP) (U.S. Environmental Protection Agency, 2019) suggest that numerous major CO2 emitters are located within 50 km of the existing pipeline network that provides CO2 for EOR in the Permian Basin. The costs for connecting these potential sources of CO2 to the existing transportation infrastructure could be very low. Of these potential sources of anthropogenic CO2, the leading emitters are coal-fired electricity generation plants, and the sources with next-largest emissions are natural gas-fired power plants. However, the CO2 concentrations in the emission streams of these types of power plants is typically far lower than that for ethanol plants and some other industrial facilities (including natural gas processing plants), which causes the estimated capture costs (using currently available technologies) to be far higher, in general. In addition, the potential cost (per metric ton of CO2 supplied) of adding these new sources of anthropogenic CO2 for EOR in the Permian basin could be greater than expanding production of existing suppliers and developing new sources of natural CO2. On the other hand, their proximity to the existing pipeline network could allow them to be viable sources of anthropogenic CO2 for EOR in the Permian Basin, and the relative competitiveness of these sources with the existing use of natural CO2 could be further enhanced if they qualify for the recently revised 45Q tax credit (Heitkamp, 2017). The results of this study provide some estimates of the potential gaps in the costs of CO2 supply from these distinct sources, and the potential implications of the results for the market conditions that could be necessary to overcome those gaps are discussed.

Mycobacterium salmoniphilum sp. nov. from salmonoid fishes

Released November 27, 2019 14:30 EST

1960, American Review of Respiratory Disease (81) 241-250

A.J. Ross

The presence of mycobacteria in salmonoid fishes was first recorded by Earp, Ellis, and Ordal (1) in 1953. Acid-fast bacilli had previously been reported from other cold-blooded animals including fishes of fresh-water and marine origin; recent reviews have been presented by Vogel (2) and Parisot (3).

The initiation of an intensive search for bacteria of this group revealed their widespread distribution in salmonoid fish populations. Acidfast bacilli have been demonstrated in livers and kidneys of salmon and trout in Washington, Oregon, and California, as well as from salmon taken in Alaskan waters. While the organisms are generally considered to be associated with fish of hatchery origin (4), they have also been found in young and adult fish from areas presumably supporting only wild populations. Wood and Ordal (4) indicate that the incidence of the tuberculosis-like infection is directly related to the length of time the fish are reared in the hatchery prior to release. This may result from a common hatchery practice of feeding viscera and carcasses from spawned-out adults to juvenile fish. Therefore, in many instances viable mycobacteria are present in the food of young fish.


3D geologic framework for use with the U.S. Geological Survey National Crustal Model, Phase 1—Western United States

Released November 27, 2019 11:10 EST

2019, Open-File Report 2019-1081

Oliver S. Boyd

A 3D geologic framework is presented here as part of the U.S. Geological Survey National Crustal Model for the western United States, which will be used to improve seismic hazard assessment. The framework is based on 1:250,000 to 1:1,000,000-scale state geologic maps and depths of multiple subsurface unit boundaries. The geology at or near the Earth’s surface is based on published maps with modifications to remove discontinuities across state borders. Extrapolation of rock type and age in the subsurface is achieved by iterative stripping of units of a given age, nearest neighbor interpolation of the remaining units, and constraints on basement geology. The subsurface depth of the interfaces between units is determined by a range of models with varying quantity and quality of constraints. Bedrock depth is derived primarily from a proxy model with added geophysical constraint in some areas. The depths to the base of Cenozoic and Phanerozoic sedimentary and extrusive volcanic rocks are constrained by geophysical methods in many areas. Elsewhere, a simple method is used to estimate their subsurface depth based on the distance to the edge of the geologic units. The remaining continental units are evenly distributed above, below, and between depending on age. The oceanic crust is treated as a simple four-layer model with the added complexity of subduction beneath the North American plate along the Cascadia subduction zone.

Refinements to this technique may be accomplished in future versions of the model with more specific information including the location of faults to produce discontinuities in geologic structure and additional information obtained from boreholes and geophysical studies. Further improvements to the geologic framework may be made by incorporating information from more local studies, for example, hydrogeologic studies.

Groundwater characterization of the Madison aquifer near Jewel Cave National Monument, South Dakota

Released November 27, 2019 10:20 EST

2019, Fact Sheet 2019-3072

Joshua F. Valder, Janet M. Carter, Michael E. Wiles, Sierra M. Heimel

Jewel Cave National Monument in the Black Hills of southwestern South Dakota has more than 200 miles of mapped cave passages and several subterranean lakes that have been discovered since 2015. Jewel Cave is one of the world’s longest known caves and its natural beauty and unique natural cave features led U.S. President Theodore Roosevelt to designate the cave as a national monument in 1908. Jewel Cave was naturally formed in the regionally extensive Madison Limestone, which is characterized as a carbonate karst environment (containing caves and sinkholes) with extensive subterranean cave networks and losing streams at the land surface. Preserving and protecting the cave is an important element of the National Park Service mission, and understanding the hydrogeologic connection between the surface and the subsurface is essential for ensuring the preservation and protection of the cave for future generations. A component in preserving and protecting the park includes the improved understanding of groundwater flow and vulnerability of the subsurface, which allows scientists, park managers, the visiting public, and the surrounding communities to better manage, protect, and preserve the site and its unique natural features.

Groundwater-flow model and analysis of groundwater and surface-water interactions for the Big Sioux aquifer, Sioux Falls, South Dakota

Released November 27, 2019 06:42 EST

2019, Scientific Investigations Report 2019-5117

Kyle W. Davis, William G. Eldridge, Joshua F. Valder, Kristen J. Valseth

The city of Sioux Falls, in southeastern South Dakota, is the largest city in South Dakota. The U.S. Geological Survey (USGS), in cooperation with the city of Sioux Falls, completed a groundwater-flow model to use for improving the understanding of groundwater-flow processes, estimating hydrogeologic properties, and analyzing groundwater and surface-water interactions for the Big Sioux aquifer in the model area.

The model area includes the Big Sioux aquifer and the underlying hydrogeologic units from Dell Rapids, South Dakota, to the confluence of the Big Sioux River and the outlet of the Sioux Falls Diversion Channel in eastern Sioux Falls, S. Dak. The Big Sioux aquifer is the primary aquifer in the model area and the focus of the groundwater-flow model. The Big Sioux River is the largest stream in the model area and is in hydraulic connection with the Big Sioux aquifer.

A conceptual model for the area was constructed and includes a characterization of the hydrogeologic framework, analysis and construction of potentiometric surfaces, and summary of estimated water budget components in the model area. The primary hydrogeologic units in the model area consist of (1) the Big Sioux aquifer, (2) a glacial till confining unit, and (3) bedrock aquifers (Split Rock Creek and Sioux Quartzite aquifers). Sources of groundwater recharge included infiltration of precipitation, stream seepage, and groundwater exchanges among the hydraulically connected Big Sioux aquifer, glacial till confining unit, and bedrock aquifers. Groundwater losses included evapotranspiration, groundwater discharge to streams, and groundwater withdrawal to supply water-use needs.

A numerical groundwater-flow model (numerical model) was constructed and was used to simulate all aspects of the conceptual model for predevelopment (steady-state) and time-varying (transient) monthly conditions for 1950–2017. The numerical model was constructed using the USGS modular hydrologic simulation program, MODFLOW–6, and was calibrated using the Parameter ESTimation software, PEST++.

The transient numerical model was calibrated for steady-state and transient monthly conditions for 1950–2017. Calibration targets were observations of hydraulic head, changes in hydraulic head, monthly mean streamflow (as a rate), and cumulative monthly stream discharge (as a volume). Parameters adjusted during model calibration were horizontal and vertical hydraulic conductivity, specific storage, specific yield, recharge and evapotranspiration multipliers, and streambed hydraulic conductivity. Horizontal and vertical hydraulic conductivity were estimated at pilot points distributed within the model area; specific storage and specific yield were assigned to uniform values in each layer in the model area; recharge and evapotranspiration multipliers were assigned uniformly for every stress period in the numerical model; and streambed hydraulic conductivity values were assigned uniformly between stream confluences.

The final calibrated parameter values of horizontal and vertical hydraulic conductivity, specific yield, specific storage, streambed hydraulic conductivity, recharge, and evapotranspiration were considered reasonable for the hydrogeologic materials and conditions in the model area for 1950–2017.

Overall, simulated hydraulic head altitudes had a linear regression coefficient of determination (R2) of 0.48. Hydraulic head altitude residuals for the glacial till confining unit and bedrock aquifers were typically greater in magnitude when compared to residuals in the Big Sioux aquifer, but simulated hydraulic head altitudes in the Big Sioux aquifer compared favorably with mean observed hydraulic head altitudes and had a linear regression R2 of 0.93.

Simulated streamflow hydrographs matched the general trends of observed increases and decreases in streamflow for USGS streamgages 06482000 (Big Sioux River at Sioux Falls, S. Dak.) and 06482020 (Big Sioux River at North Cliff Avenue at Sioux Falls, S. Dak.), but larger streamflows were overestimated at the first streamgage and underestimated at the second streamgage. The numerical model reasonably estimated cumulative monthly stream discharge for the first 10–15 years of available streamflow records at both USGS streamgages. After the first 10–15 years of available streamflow record, cumulative monthly stream discharge was closely estimated for USGS streamgage 06482000 and underestimated at USGS streamgage 06482020.

Composite sensitivities without regularization were calculated by PEST++ for the calibrated numerical model parameters and were averaged by parameter group. The parameter group with the highest mean composite sensitivity was the recharge multiplier parameter group.

Model simplifications, assumptions, and limitations were necessary for construction of the conceptual and numerical models and for calibration efficiency. Spatial simplification of hydraulic properties could cause the numerical model to misrepresent reactions to changes in localized stresses, such as additional demands for groundwater withdrawal. The numerical model was temporally discretized into monthly periods and required scaling daily rates into representative monthly rates for model input and calibration targets. Based on the comparison between the observed and simulated groundwater levels, monthly mean streamflow and cumulative monthly stream discharge, and general groundwater distribution and flow, the numerical model favorably simulated the flow in the Big Sioux aquifer.

Eventual capture was calculated in the model area using a steady-state numerical groundwater-flow model. The eventual capture map shows areas of higher streamflow capture adjacent to the Big Sioux River north of the city of Sioux Falls and along the lower part of the Sioux Falls Diversion Channel, and areas of lower streamflow capture along aquifer boundaries and near the southern Sioux Quartzite barrier.

The timing of capture was determined using a transient numerical groundwater-flow model to determine the likely captured water sources for 30 years of groundwater withdrawal at three hypothetical wells using three continuous withdrawal rates (112.5, 450.0, and 900.0 gallons per minute). Supply for all three hypothetical wells became capture-dominated after only a short period of continuous withdrawal. Capture stabilized after about 10–15 years for well A, and after 20–25 years for well B, and after about 10–15 years for well C.

The groundwater-flow model is a suitable tool to use for improving the understanding of groundwater-flow processes, estimating hydrogeologic properties, and analyzing groundwater and surface-water interactions for the Big Sioux aquifer near Sioux Falls, S. Dak. The numerical model can be used to simulate hydrologic scenarios, advance understanding of groundwater budgets, compute system response to stress, and determine likely sources of water supplied to wells.

Aeromagnetic surveys in Afghanistan: An updated website for distribution of data

Released November 26, 2019 16:00 EST

2011, Open-File Report 2011-1055

Ghulam Sakhi Shenwary, Abdul Hakim Kohistany, Sardar Hussain, Said Ashan, Abdul Salam Mutty, Mohammad Ahmad Daud, Michael D. Wussow, Ronald E. Sweeney, Jeffrey D. Phillips, Charles R. Lindsay, Robert P. Kucks, Carol A. Finn, Benjamin J. Drenth, Eric D. Anderson, Jared D. Abraham, Robert T. Liang, James L. Jarvis, Joan M. Gardner, Vicki A. Childers, David C. Ball, John M. Brozena

Because of its geologic setting, Afghanistan has the potential to contain substantial natural resources. Although valuable mineral deposits and petroleum resources have been identified, much of the country's potential remains unknown. Airborne geophysical surveys are a well accepted and cost effective method for obtaining information about the geological setting of an area without the need to be physically located on the ground. Owing to the current security situation and the large areas of the country that have not been evaluated by geophysical exploration methods, a regional airborne geophysical survey was proposed. Acting upon the request of the Islamic Republic of Afghanistan Ministry of Mines, the U.S. Geological Survey contracted with the Naval Research Laboratory to jointly conduct an airborne geophysical and remote sensing survey of Afghanistan.

Data from theodolite measurements of creep rates on San Francisco Bay region faults, California, 1979-2012

Released November 26, 2019 14:45 EST

2009, Open-File Report 2009-1119

Forrest S. McFarland, James J. Lienkaemper, S. John Caskey


Our purpose is to annually update our creep-data archive on San Francisco Bay region active faults for use by the scientific research community. Earlier data (1979-2001) were reported in Galehouse (2002) and were analyzed and described in detail in a summary report (Galehouse and Lienkaemper, 2003). A complete analysis of our earlier results obtained on the Hayward Fault was presented in Lienkaemper, Galehouse and Simpson (2001) and updated in Lienkaemper and others (2012). Lienkaemper and others (2014) provide a new overview and analysis of fault creep along all sections of the northern San Andreas Fault system, from which they estimate by how much fault creep reduces the seismic hazard for each fault section.

From 1979 until his retirement from the project in 2001, Jon Galehouse of San Francisco State University (SFSU) and many student research assistants measured creep (aseismic slip) rates on these faults. The creep measurement project, which was initiated by Galehouse, continued through the Geosciences Department at SFSU from 2001-2006 under the direction of Karen Grove and John Caskey (Grove and Caskey, 2005) and since 2006 under Caskey (2007). Forrest McFarland has managed most of the technical and logistical project operations, as well as data processing and compilation since 2001. Data from 2001-2007 are found in McFarland and others (2007). From 2009 onward, we have released the raw data annually using this report (OF2009-1119) as a permanent publication link, while publishing more detailed analyses of these data in the scientific literature, such as Lienkaemper and others (2014).

We maintain a project Web site (http://funnel.sfsu.edu/creep/) that includes the following information: project description, project personnel, creep characteristics and measurement, map of creep-measurement sites, creep-measurement site information, and links to data plots for each measurement site. Our most current, annually updated results are, therefore, accessible to the scientific community and to the general public. Information about the project can currently be requested by the public by an email link (fltcreep@sfsu.edu) found on our project Web site.

Integrating hydrology and biogeochemistry across frozen landscapes

Released November 26, 2019 11:43 EST

2019, Nature Communications (10)

Jorien Vonk, Suzanne Tank, Michelle Ann Walvoord

Research has traditionally focused on atmospheric release of carbon from thawing permafrost, yet overlooked waterborne release pathways likely contribute significantly, especially in a warming Arctic. To address this knowledge gap and better constrain the fate of carbon in the North, we recommend inter-disciplinary efforts bridging physical, chemical and computational research.

Report of the River Master of the Delaware River for the period December 1, 2009–November 30, 2010

Released November 26, 2019 10:35 EST

2019, Open-File Report 2019-1093

Kendra L. Russell, Darwin Ockerman, Bruce E. Krejmas, Gary N. Paulachok, Robert R. Mason, Jr.

A Decree of the Supreme Court of the United States, entered June 7, 1954, established the position of Delaware River Master within the U.S. Geological Survey. In addition, the Decree authorizes diversion of water from the Delaware River Basin and requires compensating releases from certain reservoirs, owned by New York City, to be made under the supervision and direction of the River Master. The Decree stipulates that the River Master will furnish reports to the Court, not less frequently than annually. This report is the 57th Annual Report of the River Master of the Delaware River. It covers the 2010 River Master report year, the period from December 1, 2009, to November 30, 2010.

During the report year, precipitation in the upper Delaware River Basin was 49.38 inches or 112 percent of the long-term average. Combined storage in Pepacton, Cannonsville, and Neversink Reservoirs remained high much of the year and did not decline below 80 percent of combined capacity until September 2010. A lower basin drought warning was issued by the Delaware River Basin Commission on September 24, 2010. It automatically ended on October 31, 2010, when the reservoir contents rose above drought levels, due in large part to heavy rainfall during the last week of September. River Master operations during the year were conducted as stipulated by the Decree and the Flexible Flow Management Program.

Diversions from the Delaware River Basin by New York City and New Jersey were in full compliance with the Decree. Reservoir releases were made as directed by the River Master at rates designed to meet the flow objective for the Delaware River at Montague, New Jersey, on 81 days during the report year. Interim Excess Release Quantity and conservation releases, designed to relieve thermal stress and protect the fishery and aquatic habitat in the tailwaters of the reservoirs, were made during the report year.

The quality of water in the Delaware Estuary between Trenton, New Jersey, and Reedy Island Jetty, Delaware, was monitored at various locations. Data on water temperature, specific conductance, dissolved oxygen, and pH were collected continuously by electronic instruments at four sites.

Phenology patterns indicate recovery trajectories of ponderosa pine forests after high-severity fires

Released November 26, 2019 08:49 EST

2019, Remote Sensing (11)

Jessica Walker, Christopher E. Soulard

Post-fire recovery trajectories in ponderosa pine (Pinus ponderosa Laws.) forests of the US Southwest are increasingly shifting away from pre-burn vegetation communities. This study investigated whether phenological metrics derived from a multi-decade remotely sensed imagery time-series could differentiate among grass, evergreen shrub, deciduous, or conifer-dominated replacement pathways. We focused on 10 fires that burned ponderosa pine forests in Arizona and New Mexico, USA before the year 2000. A total of 29 sites with discernable post-fire recovery signals were selected within high-severity burn areas. At each site, we used Google Earth Engine to derive time-series of normalized difference vegetation index (NDVI) signals from Landsat Thematic Mapper, Enhanced Thematic Mapper+, and Operational Line Imager data from 1984 to 2017. We aggregated values to 8- and 16-day intervals, fit Savitzy-Golay filters to each sequence, and extracted annual phenology metrics of amplitude, base value, peak value, and timing of peak value in the Timesat analysis package. Results show that relative to post-fire conditions, pre-burn ponderosa pine forests exhibit significantly lower mean NDVI amplitude (0.14 vs. 0.21), higher mean base NDVI (0.47 vs. 0.22), higher mean peak NDVI (0.60 vs. 0.43), and later mean peak NDVI (day of year 277 vs. 237). Vegetation succession exhibits distinct phenometric characteristics as early as year five (amplitude) and as late as year 20 (timing of peak NDVI). This study confirms the feasibility of leveraging phenology metrics derived from long-term imagery time series to identify and monitor ecological outcomes. This information may be of benefit to land resource managers who seek indicators of future landscape composition to inform management strategies.

Employing an ecosystem services framework to deliver decision ready science

Released November 26, 2019 07:06 EST

2019, Advances in Ecological Research (4) 302-323

Emily J. Pindilli, Dianna M. Hogan, Zhiliang Zhu

Public land managers have limited information to allow for the integration and balancing of multiple objectives in land management decisions including the social (cultural and health), economic (monetary and nonmonetary), and environmental aspects. In this article, we document an approach to consider the many facets of decision making by incorporating them into a decision context using an ecosystem services framework. This analysis is based on a multi-partner project led by the US Geological Survey and the US Fish and Wildlife Service to provide land management decision support for the Great Dismal Swamp National Wildlife Refuge. It is an integrated ecologic-economic analysis of baseline (current) and potential future quantities, qualities, and values of selected ecosystem services from the Refuge. Alternative management scenarios are modeled to consider the impact of specific management actions or natural disturbances on priority ecosystem services. We examine the benefits and challenges of using this framework. Key lessons learned from this effort include the mismatch in timing between physical and social science; the challenge of integrating methods from multiple disciplines; the importance of frequent communication to overcome siloed research; and the utility of an integrating framework for ecosystem services and supporting tools such as the dynamic ecosystem model.

Pecos River Basin salinity assessment, Santa Rosa Lake, New Mexico, to the confluence of the Pecos River and the Rio Grande, Texas, 2015

Released November 25, 2019 16:39 EST

2019, Scientific Investigations Report 2019-5071

Natalie A. Houston, Jonathan V. Thomas, Patricia B. Ging, Andrew P. Teeple, Diana E. Pedraza, David S. Wallace

The elevated salinity of the Pecos River throughout much of its length is of paramount concern to water users and water managers. Dissolved-solids concentrations in the Pecos River exceed 3,000 milligrams per liter in many of its reaches in the study area, from Santa Rosa Lake, New Mexico, to the confluence of the Pecos River with the Rio Grande, Texas. The salinity of the Pecos River increases downstream and affects the availability of useable water in the Pecos River Basin. In this report, “salinity” and “dissolved-solids concentration” are considered synonymous; both terms are used to refer to the total ionic concentration of dissolved minerals in water. The sources of salinity in the Pecos River Basin are natural (geologic) and anthropogenic, including but not limited to groundwater discharge, springs, and irrigation return flows. Previous studies in the Pecos River Basin were project specific and designed to address salinity issues in specific parts of the basin; therefore, in 2015, the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers, New Mexico Interstate Stream Commission, Texas Commission on Environmental Quality, and Texas Water Development Board assessed the major sources of salinity throughout the extent of the basin where elevated salinity in the Pecos River is well documented (that is, in the drainage area of the Pecos River from Santa Rosa Lake to the confluence of the Pecos River and the Rio Grande). The goal was to gain a better understanding of how specific areas might be contributing to the elevated salinity in the Pecos River and how salinity of the Pecos River has changed over time. This assessment includes a literature review and compilation of previously published salinity-related data, which guided the collection of additional water-quality samples and streamflow gain-loss measurements. Differences in water quality of surface-water and groundwater samples, streamflow measurements, and geophysical data were assessed to gain new insights regarding sources of salinity in the Pecos River Basin and a more detailed assessment of potential areas of elevated salinity in the basin. The datasets compiled for this assessment are available in a companion data release.

The literature review identified several potential sources of salinity inputs to the Pecos River in New Mexico and Texas. In New Mexico, sources of salinity inputs included sinkhole springs discharging into El Rito Creek, the Bitter Lake National Wildlife Refuge inflow to the Pecos River, inflow from the Rio Hondo, including the main channel and a restored channel at the Bitter Lake National Wildlife Refuge referred to as the “Rio Hondo spring channel,” the outflow from Lea Lake at Bottomless Lakes State Park, and the Malaga Bend region of the Pecos River. In Texas, sources of salinity inputs included Salt Creek downstream from Red Bluff Reservoir and the area near the Horsehead Crossing ford on the Pecos River.

The compilation of historical water-quality data revealed a lack of consistent sampling of the same constituents at the same sites along the main stem of the Pecos River, which results in data gaps that hinder the ability to effectively analyze long-term changes in water quality that may help with the understanding of how salinity in the Pecos River has changed over time and identifying the sources of salinity in the Pecos River Basin. To help fill these data gaps, water-quality and streamflow data were collected in the study area in February 2015 by the U.S. Geological Survey. Historical water-quality data and newly collected data from February 2015 were evaluated for selected major-ion concentrations, dissolved-solids concentrations, and deuterium, oxygen, and strontium isotopes. Analysis of the data indicated several areas of increasing salinity in the Pecos River. Most notable increases were in two subreaches of the river, between Acme, N. Mex., and Artesia, N. Mex., and between Orla, Tex., and Grandfalls, Tex. Increasing sodium and chloride concentrations from Acme to Artesia coincided with changes in isotopic ratios within the Pecos River Basin. Changes in isotopic ratios in this reach indicate a likely inflow from an isotopically different source of water compared to the water in the main stem of the Pecos River, such as groundwater inflow, inflow from surface-water features distinct from the main stem of the Pecos River, or both. In the subreach between Orla and Grandfalls, an increase in dissolved-solids concentrations was observed along with a shift in isotope values, indicating that neither evaporative processes in Red Bluff Reservoir nor inflow from Salt Creek likely solely influences the salinity of the Pecos River in this subreach. The highest dissolved-solids concentrations in the Pecos River Basin were measured downstream from Grandfalls, where dissolved-solids concentrations are greater than 16,000 milligrams per liter near Iraan, Tex. Changes in isotopic values (deuterium, oxygen, and strontium) indicate mixing of different waters at several areas along the main stem of the Pecos River. The spatial distribution of the areas of interest from the literature review and the water-quality data are available in the companion data release.

A practical primer on geostatistics

Released November 25, 2019 11:05 EST

2018, Open-File Report 2009-1103

Ricardo A. Olea


The Challenge—Most geological phenomena are extraordinarily complex in their interrelationships and vast in their geographical extension. Ordinarily, engineers and geoscientists are faced with corporate or scientific requirements to properly prepare geological models with measurements involving a small fraction of the entire area or volume of interest. Exact description of a system such as an oil reservoir is neither feasible nor economically possible. The results are necessarily uncertain. Note that the uncertainty is not an intrinsic property of the systems; it is the result of incomplete knowledge by the observer.

The Aim of Geostatistics—The main objective of geostatistics is the characterization of spatial systems that are incompletely known, systems that are common in geology. A key difference from classical statistics is that geostatistics uses the sampling location of every measurement. Unless the measurements show spatial correlation, the application of geostatistics is pointless. Ordinarily the need for additional knowledge goes beyond a few points, which explains the display of results graphically as fishnet plots, block diagrams, and maps.

Geostatistical Methods—Geostatistics is a collection of numerical techniques for the characterization of spatial attributes using primarily two tools: probabilistic models, which are used for spatial data in a manner similar to the way in which time-series analysis characterizes temporal data, or pattern recognition techniques. The probabilistic models are used as a way to handle uncertainty in results away from sampling locations, making a radical departure from alternative approaches like inverse distance estimation methods.

Differences with Time Series—On dealing with time-series analysis, users frequently concentrate their attention on extrapolations for making forecasts. Although users of geostatistics may be interested in extrapolation, the methods work at their best interpolating. This simple difference has significant methodological implications.

Historical Remarks—As a discipline, geostatistics was firmly established in the 1960s by the French engineer Georges Matheron, who was interested in the appraisal of ore reserves in mining. Geostatistics did not develop overnight. Like other disciplines, it has built on previous results, many of which were formulated with different objectives in various fields.

Pioneers—Seminal ideas conceptually related to what today we call geostatistics or spatial statistics are found in the work of several pioneers, including: 1940s: A.N. Kolmogorov in turbulent flow and N. Wiener in stochastic processing; 1950s: D. Krige in mining; 1960s: B. Mathern in forestry and L.S. Gandin in meteorology

Calculations—Serious applications of geostatistics require the use of digital computers. Although for most geostatistical techniques rudimentary implementation from scratch is fairly straightforward, coding programs from scratch is recommended only as part of a practice that may help users to gain a better grasp of the formulations.

Software—For professional work, the reader should employ software packages that have been thoroughly tested to handle any sampling scheme, that run as efficiently as possible, and that offer graphic capabilities for the analysis and display of results. This primer employs primarily the package Stanford Geomodeling Software (SGeMS) - recently developed at the Energy Resources Engineering Department at Stanford University - as a way to show how to obtain results practically. This applied side of the primer should not be interpreted as the notes being a manual for the use of SGeMS. The main objective of the primer is to help the reader gain an understanding of the fundamental concepts and tools in geostatistics.

Organization of the Primer—The chapters of greatest importance are those covering kriging and simulation. All other materials are peripheral and are included for better comprehension of these main geostatistical modeling tools. The choice of kriging versus simulation is often a big puzzle to the uninitiated, let alone the different variants of both of them. Chapters 14, 18, and 19 are intended to shed light on those subjects. The critical aspect of assessing and modeling spatial correlation is covered in chapter 7. Chapters 2 and 3 review relevant concepts in classical statistics.

Course Objectives—This course offers stochastic solutions to common problems in the characterization of complex geological systems. At the end of the course, participants should have: an understanding of the theoretical foundations of geostatistics; a good grasp of its possibilities and limitations; and reasonable familiarity with the SGeMS software, thus opening the possibility of practically applying geostatistics.

Evaluating associations between environmental variables and Escherichia coli levels for predictive modeling at Pawtuckaway Beach in Nottingham, New Hampshire, from 2015 to 2017

Released November 25, 2019 09:35 EST

2019, Scientific Investigations Report 2019-5111

James F. Coles, Kathleen F. Bush

From 2015 through 2017, the U.S. Geological Survey in cooperation with the New Hampshire Department of Health and Human Services and the New Hampshire Department of Environmental Services studied occurrences of high levels of Escherichia coli (E. coli) bacteria at the Pawtuckaway State Park Beach in Nottingham, New Hampshire. Historic data collected by the New Hampshire Department of Environmental Services indicated that E. coli concentrations in the water typically increased through the beach season to levels considered potentially harmful to beachgoers. During the three beach seasons that were studied, E. coli samples were collected three to four times per week, and water-quality and meteorological data were collected continuously. The Virtual Beach software was used to generate a predictive model for each year of the study (2015–2017), and the model for each of these years was tested with data from the other two. Additionally, data from all study years were combined to generate a comprehensive model to help identify independent variables that might characterize environmental conditions relative to E. coli levels during multiple seasons. The accuracy of the models in predicting the occurrence of high E. coli levels was marginal, but the models did provide insights into the likely mechanisms for increased E. coli levels during the seasons. Variables most important in explaining high E. coli levels were the presence of geese at the beach, the progression of the season, the number of visitors at the beach, and wind vectors relative to beach orientation.

Antibiotic resistant bacteria in wildlife: Perspectives on trends, acquisitions and dissemination, data gaps, and future directions

Released November 25, 2019 08:43 EST

2019, Journal of Wildlife Diseases

Andrew M. Ramey, Christina Ahlstrom

The proliferation of antibiotic resistant bacteria in the environment has potential negative economic and health consequences. Thus, previous investigations have targeted wild animals to understand the occurrence of antibiotic resistance in diverse environmental sources. In this critical review and synthesis, we summarize important concepts learned through the sampling of wildlife for antibiotic resistant indicator bacteria. These concepts are helpful for understanding dissemination of resistance through environmental pathways and helping to guide future research efforts. Our review is comprised of six sections. The first section briefly introduces antibiotic resistance as it pertains to bacteria harbored in environmental sources such as wild animals. Next, we differentiate wildlife from other animals in the context of how diverse taxa provide different information on antibiotic resistance in the environment. In the third section, we identify representative research and seminal works that illustrate important associations between the occurrence of antibiotic resistant bacteria in wildlife and anthropogenic inputs into the environment. For example, we highlight numerous investigations that support the premise that anthropogenic inputs into the environment drive the occurrence of antibiotic resistance in bacteria harbored by free-ranging wildlife. Additionally, we summarize previous research demonstrating foraging as a mechanism by which wildlife may be exposed to anthropogenic antibiotic resistance contamination in the environment. In the fourth section of our review, we summarize molecular evidence for the acquisition and dissemination of resistance among bacteria harbored by wildlife. In the fifth section, we identify what we believe to be important data gaps and potential future directions that other researchers may find useful towards the development of efficient, informative, and impactful investigations of antibiotic resistant bacteria in wildlife. Finally, we conclude our review by highlighting the need to move from surveys that simply identify antibiotic resistant bacteria in wildlife towards hypothesis-driven investigations that: (1) identify point sources of antibiotic resistance; (2) provide information on risk to human and animal health; (3) identify interventions that may interrupt environmentally mediated pathways of antibiotic resistance acquisition/transmission; and (4) evaluate whether management practices are leading to desirable outcomes.

The future of barriers and trapping methods in the sea lamprey (Petromyzon marinus) control program in the Laurentian Great Lakes

Released November 25, 2019 08:20 EST

2019, Reviews in Fish Biology and Fisheries

Scott M. Miehls, Paul Sullivan, Michael Twohey, Jessica Barber, Rodney McDonald

The Great Lakes Fishery Commission (GLFC) was created in 1955 to develop a program of eradication or management of sea lamprey populations in the Great Lakes for the protection of the Great Lakes fishery. Beginning in the 1980s the GLFC shifted to an integrated pest management (IPM) model seeking to deploy control measures which target multiple life stages. Currently control efforts focus on limiting the area of infestation using barriers to migratory adults and eradication of larvae from streams using a selective lampricide. The GLFC continues to support multiple research initiatives to develop addition control, improve current control measures, and further advance sea lamprey control. During the past six decades sea lamprey control in the Great Lakes has evolved as the research program has identified technological advances, yet description of this program evolution is scattered among grey literature and technical reports, which are often inaccessible to the outside research community. This review describes how the use of barriers and traps have changed during the history of sea lamprey control, status of these tools within the current program, and outstanding questions that need to be addressed to continue advancing sea lamprey control in the Great Lakes.

Impacts of Hurricane Irma on Florida Bay Islands, Everglades National Park, U.S.A.

Released November 22, 2019 14:15 EST

2019, Estuaries and Coasts

G. Lynn Wingard, Sarah E. Bergstresser, Bethany Stackhouse, Miriam Jones, Marci E. Marot, Kristen Hoefke, Andre Daniels, Katherine Keller

Hurricane Irma made landfall in south Florida, USA, on September 10, 2017 as a category 4 storm. In January 2018, fieldwork was conducted on four previously (2014) sampled islands in Florida Bay, Everglades National Park to examine changes between 2014 and 2018. The objectives were to determine if the net impact of the storm was gain or loss of island landmass and/or elevation; observe and quantify impacts to mangroves; and identify distinctive sedimentary, biochemical, and/or geochemical signatures of the storm. Storm overwash deposits were measured in the field and, in general, interior island mudflats appeared to experience deposition ranging from ~ 0.5 to ~ 6.5 cm. Elevation changes were measured using real-time kinematic positioning and satellite receivers. Comparison of 2014 to 2018 elevation measurements indicates mangrove berms and transitional areas between mudflats and berms experienced erosion and loss of elevation, whereas interior mudflats gained elevation, possibly due to Hurricane Irma. Geographic information system analysis of pre- and post-storm satellite imagery indicates the western-most island, closest to the eye of the storm, lost 32 to 42% (~ 11 to 13 m) of the width of the eastern berm, and vegetated coverage was reduced 9.3% or ~ 9700 m2. Vegetated coverage on the eastern-most island was reduced by 1.9% or ~ 9200 m2. These results are compared to previous accounts of hurricane impacts and provide a baseline for examining long-term constructive and destructive aspects of hurricanes on the islands and the role of storms in resiliency of Florida Bay islands.

Agricultural cropland extent and areas of South Asia derived using Landsat satellite 30-m time-series big-data using random forest machine learning algorithms on the Google Earth Engine cloud

Released November 22, 2019 06:58 EST

2019, GIScience and Remote Sensing

Murali Krishna Gumma, Prasad Thenkabail, Pardhasaradhi Teluguntla, Adam Oliphant

The South Asia (India, Pakistan, Bangladesh, Nepal, Sri Lanka and Bhutan) has a staggering 900 million people (~43% of the population) who face food insecurity or severe food insecurity as per United Nations, Food and Agriculture Organization’s (FAO) the Food Insecurity Experience Scale (FIES). The existing coarse-resolution (>250-m) cropland maps lack precision in geo-location of individual farms and have low map accuracies. This also results in uncertainties in cropland areas calculated from such products. Thereby, the overarching goal of this study was to develop high spatial resolution (30-m or better) baseline cropland extent product of South Asia for the year 2015 using Landsat satellite time-series big-data and machine learning algorithms (MLAs) on the Google Earth Engine (GEE) cloud computing platform. To eliminate the impact of clouds, ten time-composited Landsat bands (blue, green, red, NIR, SWIR1, SWIR2, Thermal, EVI, NDVI, NDWI) were derived for each of the 3 time-periods over 12 months (monsoon: Julian days 151-300; winter: Julian days 301-365 plus 1-60; and summer: Julian days 61-150), taking the every 8-day data from Landsat-8 and 7 for the years 2013-2015, for a total of 30-bands plus global digital elevation model (GDEM) derived slope band. This 31-band mega-file big data-cube was composed for each of the 5 agro-ecological zones (AEZ’s) of South Asia and formed a baseline data for image classification and analysis. Knowledge-base for the Random Forest (RF) MLAs were developed using spatially well spread-out reference training data (N=2179) in 5 AEZs. Classification was performed on GEE for each of the 5 AEZs using well-established knowledge-based and RF MLAs on the cloud. Map accuracies were measured using independent validation data (N=1185). The survey showed that the South Asia cropland product had a producer’s accuracy of 89.9% (errors of omissions of 10.1%), user’s accuracy of 95.3% (errors of commission of 4.7%) and an overall accuracy of 88.7%. The National and sub-national (districts) areas computed from this cropland extent product explained 80-96% variability when compared with the National statistics of the South Asian Countries. The full resolution imagery can be viewed at full-resolution, by zooming-in to any location in South Asia or the world, at www.croplands.org and the cropland products of South Asia downloaded from The Land Processes Distributed Active Archive Center (LP DAAC) of National Aeronautics and Space Administration (NASA) and the United States Geological Survey (USGS): https://lpdaac.usgs.gov/products/gfsad30saafgircev001/

Using δ13C and δ18O to analyze loblolly pine (Pinus taeda L.) response to experimental drought and fertilization

Released November 21, 2019 15:26 EST

2019, Tree Physiology

Wen Lin, Jean-Christophe Domec, Eric Ward, John D. Marshall, John S King, Marshall A. Laviner, Thomas R Fox, Jason B. West, Ge Sun, Steve G McNulty, Asko Noormets

Drought frequency and intensity are projected to increase throughout the southeastern USA, the natural range of loblolly pine (Pinus taeda L.), and are expected to have major ecological and economic implications. We analyzed the carbon and oxygen isotopic compositions in tree ring cellulose of loblolly pine in a factorial drought (~30% throughfall reduction) and fertilization experiment, supplemented with trunk sap flow, allometry and microclimate data. We then simulated leaf temperature and applied a multi-dimensional sensitivity analysis to interpret the changes in the oxygen isotope data. This analysis found that the observed changes in tree ring cellulose could only be accounted for by inferring a change in the isotopic composition of the source water, indicating that the drought treatment increased the uptake of stored moisture from earlier precipitation events. The drought treatment also increased intrinsic water-use efficiency, but had no effect on growth, indicating that photosynthesis remained relatively unaffected despite 19% decrease in canopy conductance. In contrast, fertilization increased growth, but had no effect on the isotopic composition of tree ring cellulose, indicating that the fertilizer gains in biomass were attributable to greater leaf area and not to changes in leaf-level gas exchange. The multi-dimensional sensitivity analysis explored model behavior under different scenarios, highlighting the importance of explicit consideration of leaf temperature in the oxygen isotope discrimination (Δ18Oc) simulation and is expected to expand the inference space of the Δ18Oc models for plant ecophysiological studies.

Availability of ground water in the branch river basin, Providence County, Rhode Island

Released November 21, 2019 14:15 EST

1974, Open-File Report 18-74

H.E. Johnston, D.C. Dickerman

Stratified glacial drift consisting largely of sand and gravel constitutes the only aquifer capable of supporting continuous yields of 100 gpm (6.3 1/s) or more to individual wells. The aquifer covers about a third of the 79 mi 2 (205 km2 ) study area, occurring mainly in stream valleys that are less than a mile wide. Its saturated thickness is commonly 40 to 60ft (12 to 18 m); its transmissivity is commonly 5,000 to 8,000 ft 2/day (460 to 740m2 /day). The aquifer is hydraulically connected to streams that cross it and much of the water from heavily pumped wells will consist of infiltration induced from them. Potential sustained yield from most parts of the aquifer is limited chiefly by the rate at which infiltration can be induced from streams or low streamflow, whichever is smaller. Ground-water withdrawals deplete streamflow; and if large-scale development of ground water is not carefully planned and managed, periods of no streamflow may result during dry weather.

Potential sustained yield varies with the scheme of well development, and is evaluated for selected areas by mathematically simulating pumping from assumed schemes of wells in models of the stream-aquifer system. Results indicate that sustained yields of 5.5, 3.4, 1.6, and 1.3 mgd (0.24, 0.15, 0.07, and 0.06 m3 /s) can be obtained from the stratified-drift aquifer near Slatersville, Oakland, Harrisville, and Chepachet, respectively. Pumping at these rates will not cause streams to go dry, if the water is returned to streams near points of withdrawal. A larger ground-water yield can be obtained, if periods of no streamflow along reaches of principal streams are acceptable.

Inorganic chemical quality of water in the stream-aquifer system is suitable for most purposes; the water is soft, slightly acidic, and generally contains less than 100 milligrams per litre of dissolved solids. Continued good quality ground water depends on maintenance of good quality of water in streams, because much of the water pumped from wells will be infiltrated from streams.

Synergistic interaction of climate and land-use drivers alter the function of North American, Prairie-pothole Wetlands

Released November 21, 2019 11:03 EST

2019, Sustainability (11)

Owen P. McKenna, Samuel Richard Kucia, David M. Mushet, Michael J. Anteau, Mark T. Wiltermuth

Prairie-pothole wetlands provide the critical habitat necessary for supporting North American migratory waterfowl populations. However, climate and land-use change threaten the sustainability of these wetland ecosystems. Very few experiments and analyses have been designed to investigate the relative impacts of climate and land-use change drivers, as well as the antagonistic or synergistic interactions among these drivers on ecosystem processes. Prairie-pothole wetland water budgets are highly dependent on atmospheric inputs and especially surface runoff, which makes them especially susceptible to changes in climate and land use. Here, we present the history of prairie-pothole climate and land-use change research and address the following research questions: 1) What are the relative effects of climate and land-use change on the sustainability of prairie-pothole wetlands? and 2) Do the effects of climate and land-use change interact differently under different climatic conditions? To address these research questions, we modeled 25 wetland basins (1949–2018) and measured the response of the lowest wetland in the watershed to wetland drainage and climate variability. We found that during an extremely wet period (1993–2000) wetland drainage decreased the time at which the lowest wetland reached its spill point by four years, resulting in 10 times the amount of water spilling out of the watershed towards local stream networks. By quantifying the relative effects of both climate and land-use drivers on wetland ecosystems our findings can help managers cope with uncertainties about flooding risks and provide insight into how to manage wetlands to restore functionality

Riparian soil nitrogen cycling and isotopic enrichment in response to a long-term salmon carcass manipulation experiment

Released November 21, 2019 10:41 EST

2019, Ecosphere (10)

Megan Feddern, Gordon W. Holtgrieve, Julia A. Hart, Steven Perakis, Hyejoo Ro, Tom Quinn

Pacific salmon acquire most of their biomass in the ocean before returning to spawn and die in coastal streams and lakes, thus providing subsidies of marine-derived nitrogen (MDN) to freshwater and terrestrial ecosystems. Recent declines in salmon abundance have raised questions of whether managers should mitigate for losses of salmon MDN subsidies. The ecological importance of salmon subsidies for direct consumers (e.g., bears, birds, insects) is well established; however, many studies examining the broader role of salmon nutrients have documented the presence of MDN, without demonstrating its ecological importance. This knowledge gap is particularly pronounced in terrestrial systems. To test the long-term importance of salmon to riparian ecosystems, a 20-year manipulation was performed where salmon carcasses were systematically removed from one bank and deposited on the opposite bank along the full length of a 2 km stream in southwestern Alaska. We examined the long-term effect of this manipulation on riparian soil fertility. Soil samples were taken from nine paired transects along the stream at distances 1, 3, 6, 10, and 20 m from the bank and measured for organic and inorganic nitrogen concentrations ([NH4+], [NO3-], [NOrg]) and nitrogen transformation rates (net mineralization and net nitrification). The potential presence of MDN was also measured using 15N/14N for bulk soils as well as NH4+ and NO3- soil pools. Stable isotope analyses confirmed 15N/14N was elevated on the salmon enhanced bank compared to the salmon depleted bank. However, 15N/14N values of plant-available inorganic nitrogen exceeded the 15N/14N of salmon inputs, highlighting N isotope fractionation in soils that raises significant methodological issues with standard MDN assessments. Surprisingly, despite 20 years of salmon supplementation, the presence of MDN did not cause a long-term increase in soil N availability measured immediately prior to salmon return during the peak vegetative growth season. This finding raises questions about the contribution of MDN subsidies to riparian vegetation and indicates its importance to ecosystem N biogeochemistry may be overestimated. Our findings further suggest that other site factors such as soil moisture and stand demography may influence riparian forest growth. Given that essential nutrients can also be pollutants, we urge more critical analyses of the role of MDN to inform compensatory mitigation programs targeting salmon nutrient enhancement.

Deferrisoma paleochoriense sp. nov., a thermophilic, iron(III)-reducing bacterium from a shallow-water hydrothermal vent in the Mediterranean Sea

Released November 20, 2019 18:45 EST

2016, International Journal of Systematic and Evolutionary Microbiology (66) 830-836

Ileana Perez-Rodriguez, Matthew Rawls, D. Katharine Coykendall, Dionysis I. Foustoukos

A novel thermophilic, anaerobic, mixotrophic bacterium, designated strain MAG-PB1T, was isolated from a shallow-water hydrothermal vent system in Paleochori Bay off the coast of Milos Island, Greece. The cells were Gram-negative, rugose short rods approximately 1.0 μm in length and 0.5 μm in width. Strain MAG-PB1T grew between 30 and 70°C (optimum 60°C), 0 and 50 g NaCl l-1 (optimum 15-20 g l-1) and pH 5.5 and 8.0 (optimum pH 6.0). Generation time under optimal conditions was 2.5 hours. Optimal growth occurred under chemolithoautotrophic conditions with H2 as the energy source and CO2 as the carbon source. Fe(III), Mn(IV), arsenate and selenate were used as electron acceptors. Peptone, tryptone, Casamino acids, dextrose, sucrose, yeast extract, D-fructose, α-D-glucose and D-(-)-arabinose also served as electron donors. No growth occurred in the presence of lactate or formate. G + C content of the genomic DNA was 66.7 mol%. Phylogenetic analysis of the 16S rRNA gene sequence indicated that this organism is closely related to Deferrisoma camini, a recently described genus in the Deltaproteobacteria. Based on the 16S rDNA phylogenetic analysis and on physiological, biochemical and structural characteristics, the strain was found to represent a novel species for which the name Deferrisoma paleochoriense sp. nov. is proposed. The type strain of Deferrisoma paleochoriense is MAG-PB1T (=JCM 30394 T; = DSM 29363T).

Peak streamflow and stages at selected streamgages on the Arkansas River in Oklahoma and Arkansas, May to June 2019

Released November 20, 2019 16:32 EST

2019, Open-File Report 2019-1129

Jason M. Lewis, Adam R. Trevisan

As much as 22 inches of rain fell in Oklahoma in May 2019, resulting in historic flooding along the Arkansas River in Oklahoma and Arkansas. The flooding along the Arkansas River and its tributaries that began in May continued into June 2019. Peaks of record were measured at 12 U.S. Geological Survey (USGS) streamgages on various streams in eastern and northeastern Oklahoma. This report documents the peak streamflows and stages for seven selected streamgages along the Arkansas River in Oklahoma and Arkansas. Most of the flood peaks occurred from May 26 to June 4, 2019. The historic flooding caused homes to fall into the river as a result of bank erosion, forced some towns to be evacuated, and resulted in the highest flood depths in Tulsa, Oklahoma, since 1986. Along the Arkansas River, peak streamflows were recorded at six of the seven selected USGS streamgages, with the seventh streamgage on the Arkansas River having the second highest peak of record at that site since regulation began.

Ground-motion amplification in Cook Inlet region, Alaska from intermediate-depth earthquakes, including the 2018 MW=7.1 Anchorage earthquake

Released November 20, 2019 14:53 EST

2019, Seismological Research Letters

Morgan P. Moschetti, Eric M. Thompson, John Rekoske, Mike Hearne, Peter M. Powers, Daniel E. McNamara, Carl Tape

We measure pseudospectral and peak ground motions from 44 intermediate‐depth Mw≥4.9 earthquakes in the Cook Inlet region of southern Alaska, including those from the 2018 Mw 7.1 earthquake near Anchorage, to identify regional amplification features (0.15  s period). Ground‐motion residuals are computed with respect to an empirical ground‐motion model for intraslab subduction earthquakes, and we compute bias, between‐, and within‐event terms through a linear mixed‐effects regression. Between‐event residuals are analyzed to assess the relative source characteristics of the Cook Inlet earthquakes and suggest a difference in the scaling of the source with depth, relative to global observations. The within‐event residuals are analyzed to investigate regional amplification, and various spatial patterns manifest, including correlations of amplification with depth of the Cook Inlet basin and varying amplifications east and west of the center of the basin. Three earthquake clusters are analyzed separately and indicate spatial amplification patterns that depend on source location and exhibit variations in the depth scaling of long‐period basin amplification. The observations inform future seismic hazard modeling efforts in the Cook Inlet region. More broadly, they suggest a greater complexity of basin and regional amplification than is currently used in seismic hazard analyses.

Chronic wasting disease—Research by the U.S. Geological Survey and partners

Released November 20, 2019 13:35 EST

2019, Open-File Report 2019-1109

M. Camille Hopkins, Christina M. Carlson, Paul C. Cross, Christopher J. Johnson, Bryan J. Richards, Robin E. Russell, Michael D. Samuel, Glen A. Sargeant, Daniel P. Walsh, W. David Walter


Chronic wasting disease (CWD) is the only transmissible spongiform encephalopathy, a class of invariably fatal neurodegenerative mammalian diseases associated with a misfolded cellular prion protein found in wild free-ranging animals. Because it has a long incubation period, affected animals in Cervidae (the deer family; referred to as “cervids”) may not show signs of disease for several years. While signs are not specific to CWD, affected cervids (deer, elk, moose, and reindeer) show changes in appearance (such as progressive weight loss) and changes in behavior such as stumbling, tremors, and teeth grinding. CWD can be transmitted by direct contact or through a contaminated environment. The causative prion agent is highly resistant to degradation.

In recent decades, CWD has transitioned from a novel, obscure prion disease of cervids with limited geographical distribution, to a disease that poses substantial ecological, agricultural, and economic risks across large regions of North America. Since its discovery in free-ranging elk and deer populations in the western United States in the 1980s, CWD has been reported in captive or free-ranging cervid populations in 26 States, 3 Canadian Provinces, the Republic of South Korea, Finland, Sweden, and Norway. In addition, the proportion of CWD-infected animals is increasing in many areas where the disease is already established. In some heavily affected areas, total cervid numbers have decreased over time due to CWD, which suggests that these cervid populations may not be sustainable in the long-term.

The U.S. Geological Survey (USGS) conducts wildlife disease surveillance and research to support management of CWD-affected species and their habitats. The scientific information is relevant to governmental agencies that manage wildlife and their habitats including the U.S. Fish and Wildlife Service, the National Park Service, the U.S. Department of Agriculture, and other Federal, State, and Tribal agencies as well as conservation partners (non-governmental organizations, businesses, and private landowners). Each project description in this report (1–30) includes the non-USGS collaborators (Federal, State, Tribal agencies, universities) and a USGS point of contact (principal investigator). If there are USGS publications associated with the project, a publication list is provided at the end of each project description.

Shallow-water foraminifera and other microscopic biota of Clipperton Island, tropical eastern Pacific

Released November 20, 2019 08:33 EST

2019, Atoll Research Bulletin (626)

Mary McGann, Robert W Schmieder, Louis-Philippe Loncke

The recent foraminiferal fauna and associated microbiota of Clipperton Island (10.2833°N, 109.2167°W) were investigated at 20 sites collected in the intertidal zone around the perimeter of the island and from the edge of the inner brackish-water lagoon. Due to the island’s geographic location in a low productivity zone, a lack of variable habitats on and surrounding the island, and heavy surf that pounds the exposed land, a depauperate fauna was recovered although mixed biogeographic affinities are represented. The shallow-water foraminiferal assemblage has no endemics but primarily tropical Indo-Pacific and eastern Pacific (Panamic) affinities, as well as one species of Caribbean affinity. The most abundant species are Sorites spp. and Quinqueloculina spp. Noticeably absent are any species of Amphistegina, despite the fact that they are considered ubiquitous in the tropical Pacific. The molluscan fauna has Clipperton Island endemics, a tropical Pacific/Inter-Island endemic, and tropical eastern Pacific oceanic islands/Panamic Molluscan affinities. The ostracods included endemics found restricted to Clipperton Island lagoon, as well as Indo-Pacific and Panamic Province species. The foraminifera, mollusks, and ostracods are thought to disperse to Clipperton Island by way of the North Equatorial Countercurrent and North Equatorial Current, suggesting that the island is indeed a stepping-stone for migration both east and west across the Eastern Pacific Barrier.

A parametric numerical analysis of factors controlling ground ruptures caused by groundwater pumping

Released November 19, 2019 15:52 EST

2019, Water Resources Research

Matteo Frigo, Massimiliano Ferronato, Jun Yu, Shujun Ye, Devin Galloway, Dora Carreón-Freyre, Pietro Teatini

A modeling analysis is used to investigate the relative susceptibility of various hydrogeologic configurations to aseismic rupture generation due to deformation of aquifer systems accompanying groundwater pumping. An advanced numerical model (GEPS3D) is used to simulate rupture generation and propagation for three typical processes: (i) reactivation of a preexisting fault, (ii) differential compaction due to variations in thickness of aquifer/aquitard layers constituting the aquifer system, and (iii) tensile fracturing above a bedrock ridge that forms the base of the aquifer system. A sensitivity analysis is developed to address the relative importance of various factors, including aquifer depletion, aquifer thickness, the possible uneven distribution and depth below land surface of the aquifer/aquitard layers susceptible to aquifer-system compaction, and the height of bedrock ridges beneath the aquifer system which contributes to thinning of the aquifer system. The rupture evolution is classified in two occurrences. In one, the rupture develops at the top of the aquifer or at land surface and does not propagate. In the other, the developed rupture propagates from the aquifer top toward the land surface and/or from the land surface downward. The aquifer depth is the most important factor controlling rupture evolution. Specifically, the probability of a significant rupture propagation is higher when the aquifer top is near land surface. The numerical results are processed by a statistical regression analysis to provide a general methodology for a preliminary evaluation of possible ruptures development in exploited aquifer systems susceptible to aquifer-system compaction and accompanying land subsidence. A comparison with a few representative case studies in Arizona, USA, China, and Mexico supports the study outcomes.

Geospatial scaling of runoff and erosion modeling in the Chihuahuan Desert

Released November 19, 2019 15:39 EST

2019, Applied Engineering in Agriculture (5) 733-743

Grady Ball, Kyle Douglas-Mankin

Large-scale assessments of rangeland runoff and erosion require methods to extend plot-scale parameterizations to large areas. In this study, Rangeland Hydrology and Erosion Model (RHEM) parameters were developed from plot-scale foliar and ground-cover transect data for an arid, grass-shrub rangeland in southern New Mexico, and a method was assessed to upscale transect-plot parameters to a large landscape. The transect-plot data compared favorably to corresponding cell data generated from publicly available geospatial data for total foliar cover but less favorably for litter cover and poorly for rock cover. The RHEM effective hydraulic conductivity (Ke) parameter was comparable between transect-plot and geospatial-cell methods, but the splash and sheet erosion factor (Kss) had poor agreement between the two methods. Simulated runoff and erosion reflected differences in transect-plot and geospatial-cell-based RHEM parameterizations, with low error and very good agreement for runoff but high error and poor agreement for soil loss. These results demonstrate that Ke parameters developed using geospatial data calibrated to plot data can be extrapolated to large spatial areas and provide reasonable simulation of runoff using RHEM. However, these same geospatial methods do not provide reasonable estimation of Kss or simulation of soil loss. Poor representation of litter and rock cover variables, which are highly spatially heterogeneous at the plot scale, was inadequate to accurately represent Kss or soil loss using RHEM. High resolution ground cover data, such as from unmanned aerial systems, may improve parameterization of Kss, and, ultimately, arid rangeland soil erosion simulation.

Potentiometric surface of groundwater-level altitudes near the planned Highway 270 bypass, east of Hot Springs, Arkansas, July–August 2017

Released November 19, 2019 13:49 EST

2019, Scientific Investigations Map 3444

Anna M. Nottmeier, Phillip D. Hays

The Ouachita Mountains aquifer system potentiometric-surface map is one component of the Hot Springs Bypass Groundwater Monitoring Project. The potentiometric-surface map provides a baseline assessment of shallow groundwater levels and flow directions before the construction of the Arkansas Department of Transportation planned extension of the Highway 270 bypass, east of Hot Springs, Arkansas. The map provides data regarding status of groundwater levels and potential effects on the recharge area in the Hot Springs National Park and to groundwater that supplies water to domestic users near the Highway 270 bypass.

Groundwater levels from 66 wells were measured in July–August 2017. Fifty nine of the 66 groundwater-level altitudes measured, along with select surface-water features and springs, were used to construct the Ouachita Mountains aquifer system potentiometric-surface map. The potentiometric surface, a two-dimensional representation, shows groundwater-level altitudes ranging from a maximum of 766 ft above the North American Vertical Datum of 1988 (NAVD 88) to a minimum of 443 ft NAVD 88. The spring altitudes on the potentiometric-surface map range from 534 ft to 927 ft above NAVD 88. The study area, located in the Ouachita Mountains physiographic section of the Ouachita physiographic province, comprises narrow valleys and high ridges of Stanley Shale, Hot Springs Sandstone, Arkansas Novaculite, Missouri Mountain-Polk Creek Shale, and Bigfork Chert. The highest groundwater-level altitudes observed were in the Hot Springs Sandstone, Arkansas Novaculite, and Missouri Mountain-Polk Creek Shale. The springs discharge in outcrop areas of the Stanley Shale, Bigfork Chert, and Arkansas novaculite. The planned Highway 270 bypass will cut across ridges and valleys comprising these formations and, very importantly, across areas with elevations above 660 ft above NAVD 88 that define the hot springs recharge zone.

This potentiometric-surface map defines the status of the shallow groundwater potentiometric surface near the Highway 270 bypass prior to initiation of construction activities. A post-construction potentiometric map is planned. It must be noted that shallow groundwater levels are also subject to climatic effects including changes in amount and timing of precipitation and changes in temperature.

Using integrated population models for insights into monitoring programs: An application using pink-footed geese

Released November 19, 2019 11:43 EST

2020, Ecological Modelling (415)

Fred Johnson, Guthrie S. Zimmerman, Gitte H. Jensen, Kevin K. Clausen, Morten Frederiksen, Jesper Madsen

Development of integrated population models (IPMs) assume the absence of systematic bias in monitoring programs, yet many potential sources of systematic bias in monitoring data exist (e.g., under-counts of abundance). By integrating multiple sources of data, we can assess whether various sources of monitoring data provide consistent inferences about changes in population size and, thus, whether monitoring programs appear unbiased. For the purposes of understanding how IPMs could provide insights for monitoring programs, we used the Svalbard breeding population of pink-footed goose (Anser brachyrhynchus) as a case study. The Svalbard pink-footed goose is a well-studied species, the focus of the first adaptive-harvest-management program in Europe, and the subject of a variety of long-term monitoring programs. We examined two formulations of an IPM, but ultimately relied on the one that provided a satisfactory fit to all the available data as based on Chi-squared goodness of fit tests. Our analyses suggest a negative bias in November counts (-20 %), a negative bias in capture-mark-recapture estimates of survival (-3 %), and a negative bias in indices of productivity (-23 %). We offer possible explanations for these biases, whether the degree of bias seems reasonable considering those explanations, and how bias might be investigated directly and ultimately avoided or corrected. Finally, we discuss implications of our work for developing IPMs and associated monitoring programs for managing pink-footed geese and other waterbird species.

Santa Barbara area coastal ecosystem vulnerability assessment

Released November 19, 2019 08:05 EST

2019, Report

M.R. Myers, D.R. Cayan, S.F. Iacobellis, J.M. Melack, R.E. Beighley, Patrick L. Barnard, J.E. Dugan, H.M. Page

The Santa Barbara Area Coastal Ecosystem Vulnerability Assessment (SBA CEVA) is a multidisciplinary research project that investigates future changes to southern Santa Barbara County climate, beaches, watersheds, wetland habitats and beach ecosystems. The target audience is local land use planners and decision makers. The main objective is to provide information that assists the Cities of Santa Barbara, Carpinteria, and Goleta, the County of Santa Barbara, and UC Santa Barbara in climate adaptation planning with a clear focus on coastal ecosystems. Led by California Sea Grant, SBA CEVA was developed from the work of three of the state’s leading ecological and climatological research programs: UCSB’s Santa Barbara Coastal Long-Term Ecological Research (LTER) Program, the UCSD Scripps Institution of Oceanography (SIO) and their activities within the California and Nevada Applications Program Regional Integrated Science and Assessment (CNAP RISA), the California 4th Climate Assessment and the Southwest Climate Science Center Program, and USGS Coastal Storm Modeling System (CoSMoS)

The Zn–Pb mineralization of Florida Canyon, an evaporite-related Mississippi Valley-type deposit in Bongará district, northern Peru

Released November 19, 2019 07:44 EST

2019, Economic Geology (114) 1621-1647

Saulo B de Oliveira, David L Leach, Caetano Juliani, Lena VS Monteiro, Craig A. Johnson

The Florida Canyon evaporite-related Zn–Pb sulfide deposit, in northern Peru, is one of the largest Mississippi Valley-type (MVT) deposits in South America. Triassic carbonate and former evaporite-bearing rocks of the Pucará Group host the ore bodies that comprise two different styles: (i) predominantly stratabound ore associated with hydrocarbon-rich porous dolostones and evaporite dissolution breccias; and (ii) high-grade ore associated with evaporite breccias representing diapiric injections along faults. A dome structure that controls the location of the ore deposit was defined by drillhole spatial data; the dome likely resulted from halokinetic processes during Andean deformation. NNE-trending steeply dipping secondary faults linked to major NW structures appear to control the distribution of ore grades in the deposit. Mineralization post-dated hydrocarbon migration and accumulation. Strontium, carbon, and oxygen data isotopic signatures allow distinction between pre-and syn-mineralization carbonate stages. The sulfur isotopic composition of sulfides in the deposit suggests they precipitated as the result of mixing of a metal-rich fluid with resident hydrogen sulfide in the dome. Local thermochemical sulfate reduction (TSR) may have contributed to the reduced sulfur budget during mineralization.

Field trip guide to Mount St. Helens, Washington—Recent and ancient volcaniclastic processes and deposits

Released November 18, 2019 18:08 EST

2019, Scientific Investigations Report 2017-5022-E

Richard B. Waitt, Jon J. Major, Richard P. Hoblitt, Alexa R. Van Eaton, Michael A. Clynne

This field guide explores volcanic effusions, sediments, and landforms at Mount St. Helens in Washington. A detailed synopsis outlines the eruptive history of Mount St. Helens from about 300,000 years ago through 1980 and beyond.

The five days in the field include about 28 stops and 12 potential stops. Exposures in valleys surrounding Mount St. Helens reveal records of diverse Pleistocene and Holocene processes including debris avalanche, lahar, huge water wave on a nearby lake, pyroclastic density currents (surge and flow), tephra fall, lava flow, the growth of domes, and Pleistocene glaciation. Many of the stops explore effects of the several catastrophes that constituted the 18 May 1980 eruption and made Mount St. Helens famous.

Differentiating sediment sources using sediment fingerprinting techniques, in the Sprague River Basin, South-Central Oregon

Released November 18, 2019 13:59 EST

2019, Open-File Report 2019-1120

Liam N. Schenk, Tessa M. Harden, Julia K. Kelson

Identifying sources of sediment to streams in the Sprague River Basin, in south-central Oregon, is important for restoration efforts that are focused on reducing sediment erosion and transport. Reducing sediment loads in these streams also contributes to compliance with the total maximum daily load reduction requirements for total phosphorus in this basin. In the Sprague River Basin, phosphorus occurs in surface waters in both dissolved phase and particulate phase, and particulate phosphorus is readily transported in streams on fine-grained suspended sediments, which eventually deposit in Upper Klamath Lake. The lake has seasonal blooms of cyanobacteria that require phosphorus for growth and degrade water-quality conditions, violating State water-quality standards and creating conditions that are stressful to two endangered suckers that reside in the lake. Identifying sources of sediment to the Sprague River could help inform restoration actions by determining the principal locations in the basin contributing fine sediment to the river. The U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, conducted a proof-of-concept study to determine if sediment fingerprinting can differentiate sources of bank erosion by source material, basin, river reach, and soil horizon. The sediment fingerprinting approach uses properties of streambank and streambed sediment to differentiate between multiple sediment sources by determining a composite signature, or fingerprint. The composite fingerprint is established by combining fingerprint properties from laboratory results of elemental analysis, stable isotopes, and total carbon and nitrogen. The methods for differentiating sediment samples for this study include grouping bank and bed samples by basin, river reach, and soil horizon, and using non-parametric statistics to determine which fingerprint properties could be used to differentiate the sample groups. Results indicate that fingerprint properties differentiated source material, river reach, and basin, and were more successful at differentiating samples grouped by geographic location (basin and reach) compared to source material. Source material (banks, bed, levees) were differentiated with three fingerprint properties—Antimony (Sb), copper (Cu), and manganese (Mn). The basin category (South Fork and main-stem Sprague River) differentiated the South Fork and main stem with stable nitrogen isotopes (δ15N), aluminum (Al), silicon (Si), and vanadium (V). Specific river reaches within the study area were differentiated with 11 different fingerprint properties. These results can be used for apportionment studies using suspended sediment samples and mixing models to determine sediment source contributions within the basin.

Woods Hole Coastal and Marine Science Center—2018 annual report

Released November 18, 2019 13:55 EST

2019, Circular 1460

Sara Ernst

The 2018 annual report of the U.S. Geological Survey Woods Hole Coastal and Marine Science Center summarizes the work of the center, as well as the work of each of its science groups, highlights accomplishments of 2018, and includes a list of publications published in 2018. This product allows readers to gain a general understanding of the focus areas of the center’s scientific research and learn more about specific projects and progress made throughout 2018, all while enjoying applicable photos taken in the field and of various models, maps, and web pages.

Yellowstone Volcano Observatory 2017 annual report

Released November 18, 2019 13:02 EST

2019, Circular 1456

Yellowstone Volcano Observatory

The Yellowstone Volcano Observatory (YVO) monitors volcanic and hydrothermal activity associated with the Yellowstone magmatic system, conducts research into magmatic processes occurring beneath Yellowstone Caldera, and issues timely warnings and guidance related to potential future geologic hazards. This report summarizes the activities and findings of YVO during the year 2017, focusing on the Yellowstone magmatic system. The most noteworthy event of the year was the Maple Creek earthquake swarm of June–September, about 15 kilometers north-northwest of West Yellowstone, Montana. Over 2,400 earthquakes were located, including a felt magnitude 4.4 earthquake on June 15. Deformation was mostly consistent throughout the year, with uplift of the Norris Geyser Basin area and subsidence of the caldera, both at rates of a few centimeters per year. The only significant interruption in this pattern was an ~2-week period of subsidence at Norris Geyser Basin in early December, after which deformation returned to uplift. Field work in 2017, conducted under research permits granted by the National Park Service, included routine maintenance visits to seismic and geodetic stations as well as deployment of a semipermanent Global Positioning System network during the summer months, installation of Multi-GAS and eddy covariance systems for tracking gas emissions at the Solfatara Plateau thermal area, deployment of a nodal seismic array in Upper Geyser Basin, and collection of gas and water samples from Boundary Creek on the western side of Yellowstone National Park.

Historical range and variation (HRV)

Released November 18, 2019 06:53 EST

2019, Book chapter, Encyclopedia of Wildfires and Wildland-Urban Interface (WUI) Fires

Robert Keane, Rachel A. Loehman

Fire-prone landscapes are experiencing rapid and potentially persistent changes as the result of complex and potentially novel interactions of anthropogenic climate changes, shifting fire regimes, exotic plant, insect, and pathogen invasions, and industrial, agricultural, and urban development. Are these landscapes fully departed from historical conditions? Should they be managed as novel environments or as landscapes in transition? Historical range and variation is a benchmark representation of the conditions that describe fully functional, healthy ecosystems or landscapes. The HRV can provide an ecological reference against which contemporary and future conditions can be evaluated to determine status, trend, and magnitude of departure. This text describes the concepts of HRV, methods for developing HRV data sets, and application of HRV for fire management. We discuss the limitations of HRV, and its use under future climates that are no longer representative of historical conditions.

Dissolved organic matter in the deep TALDICE ice core: A nano-UPLC-nano-ESI-HRMS method

Released November 18, 2019 06:40 EST

2019, Science of the Total Environment (700)

Roberta Zangrando, Veronica Zanella, Ornela Karroca, Elena Barbaro, Natalie Kehrwald, Dario Battistel, Andrea Gambaro, Carlo Barbante

Trace organic compounds in deep ice cores supply important paleoclimatic information. Untargeted analyses of dissolved organic matter provide an overview of molecular species in ice samples however, sample volumes usually required for these analyses are generally not available from deep ice cores. Here, we developed an analytical method using a nano-UPLC-nano-ESI-HRMS to detect major molecular species in ice cores. Samples (4 µL) from the TALos Dome Ice CorE (TALDICE), allowed investigating molecular species across a range of depths including during glacial and interglacial periods. We detected 317 chemical species that were tentatively assigned to fatty acids, hydroxy fatty acids and their degradation products (oxo-fatty acids and dicarboxylic acids), as well as oxidation byproducts of isoprene and monoterpenes. These compounds indicate that the main sources of the organic fraction are microbes as well as primary and secondary aerosols. Interglacial samples encompass a wide range of species including compounds from the oxidation of isoprene and monoterpenes as well as unsaturated fatty acids, while the glacial samples contained less diverse species. This difference may be due to decreased temperatures during the glacial period inhibiting terrestrial vegetation growth and increasing the sea ice extent, thereby weakening the emission sources.

Trace metal and nutrient loads from groundwater seepage into the South Fork Coeur d’Alene River near Smelterville, northern Idaho, 2017

Released November 15, 2019 19:20 EST

2019, Scientific Investigations Report 2019-5113

Lauren M. Zinsser

The Coeur d’Alene mining district in northern Idaho historically was a globally important source of lead, zinc, and silver, but over 100 years of mining has left a legacy of metals contamination in the Coeur d’Alene River valley. Previous studies by the U.S. Geological Survey (USGS) and others have indicated that groundwater discharging into the South Fork Coeur d’Alene River between Kellogg and Smelterville, Idaho, is a substantial source of dissolved zinc, dissolved cadmium, and total phosphorus. As part of its ongoing cleanup efforts, the U.S. Environmental Protection Agency is constructing a groundwater collection and treatment system to intercept and treat this contaminated water before it reaches the river.

To establish conditions prior to construction, the USGS conducted a seepage study in September 2017 to quantify the rate and quality of groundwater discharging into the South Fork Coeur d’Alene River between Kellogg and Smelterville. Repeated measurements of streamflow were taken at multiple locations in the river and tributaries, and water-quality samples were collected and analyzed for trace metals and nutrients. Results showed consistent increases in streamflow (5.8 ± 1.3 cubic feet per second); and in dissolved zinc (85 ± 9.3 kilograms per day [kg/d]), dissolved cadmium (0.58 ± 0.10 kg/d) and total phosphorus (6.3 ± 0.45 kg/d) loads in a discrete segment of the reach. These gains exceeded tributary inputs, thereby implicating groundwater discharge as the main source of loading. Zinc and cadmium loads from groundwater in 2017 were less than those measured in 1999 but comparable to those measured from 2003 to 2008. This suggests that remedial actions in the late 1990s and early 2000s decreased trace-metal loading from 1999 to 2003, but that conditions remained similar from 2003 to 2017. A second seepage study will be conducted after construction and treatment plant system optimization are complete; this second study will evaluate changes in groundwater discharge to and water quality in the South Fork Coeur d’Alene River compared to the pre-construction conditions.

Using the STARS Model to evaluate the effects of the proposed project for the long-term operation of State Water Project Incidental Take Permit Application and CEQA compliance

Released November 15, 2019 16:51 EST

2019, Open-File Report 2019-1127

Russell W. Perry, Amy C. Hansen, Scott D. Evans, Tobias J. Kock

The California Department of Water Resources (DWR) requested analysis of juvenile Chinook salmon survival in the Sacramento-San Joaquin River Delta (henceforth identified as “the Delta”) as part of an effects analysis that will be included in an Incidental Take Permit (ITP) Application. This application is in compliance with the California Endangered Species Act (CESA) and Environmental Impact Report (EIR), which is itself in compliance with California Environmental Quality Act (CEQA). DWR is seeking an ITP and preparing CEQA compliance documentation for long-term operation of the State Water Project (SWP). DWR requested assistance from the U.S. Geological Survey to aid in determining the effect of the proposed project on juvenile Chinook salmon (Oncorhynchus tshawytscha) populations migrating through the Delta. Therefore, in this report we analyzed an 82-year time series of simulated river flows and Delta Cross Channel (DCC) gate operations under two scenarios constructed for the ITP: the proposed project (PP) and the existing (EX) scenarios.

To evaluate the proposed project, we used the STARS model(Survival, Travel time, And Routing Simulation model), a stochastic, individual-based simulation model designed to predict survival of a cohort of fish that experience variable daily river flows during migration through the Delta. The STARS model uses parameter estimates from a Bayesian mark-recapture model that jointly estimates travel time and survival in eight discrete reaches of the Delta and migration routing at two key river junctions.

By applying the STARS model to the two 82-year scenarios, we found that the proposed project had negative effects on survival, travel time, and routing in November but slightly positive effects in October, December, May, and June. In November, there was a high probability that survival for PP was less than EX and that travel time and routing to the Interior Delta for PP were greater than for EX. We found that the magnitude of the difference in survival between scenarios was large in some years. For example, survival under the PP scenario was 10 percent lower than EX in 25 percent of the water years in November. During this period, inflow to the Delta tended to be lower under the PP scenario, and the DCC gate was open more frequently under the PP scenario relative to the EX scenario. Lower inflow reduces survival, and more frequent operation of the DCC gate 1) increases the proportion of fish entering the Interior Delta, where survival is low, and thus 2) reduces survival in the Sacramento River in reaches downstream of the DCC. In contrast, during October, December, May, and June, survival was slightly higher, travel times were lower, and routing to the Interior Delta was lower under the PP relative to the EX scenario in the same time period, although the magnitude of the increase was relatively small in most years (less than two percent). This difference between scenarios was driven by higher river flows in some years under the PP relative to the EX scenario. Overall, the differences in survival, travel time, and routing distance between the two operational scenarios were primarily driven by the timing and magnitude of the annual high river flows.

Response of nitrogen loading to the Chesapeake Bay to source reduction and land use change scenarios: A SPARROW‐informed analysis

Released November 14, 2019 15:23 EST

2019, Journal of the American Water Resources Association

Matthew Miller, Paul D. Capel, Ana M. Garcia, Scott Ator

In response to concerns regarding the health of streams and receiving waters, the United States Environmental Protection Agency established a total maximum daily load for nitrogen in the Chesapeake Bay watershed for which practices must be in place by 2025 resulting in an expected 25% reduction in load from 2009 levels. The response of total nitrogen (TN) loads delivered to the Bay to nine source reduction and land use change scenarios was estimated using a Spatially Referenced Regression on Watershed Attributes model. The largest predicted reduction in TN load delivered to the Bay was associated with a scenario in which the mass of TN as fertilizer applied to agricultural lands was decreased. A 25% decrease in the mass of TN applied as fertilizer resulted in a predicted reduction in TN loading to the Bay of 11.3%, which was 2.5–5 times greater than the reductions predicted by other scenarios. Eliminating fertilizer application to all agricultural land in the watershed resulted in a predicted reduction in TN load to the Bay of 45%. It was estimated that an approximate 25% reduction in TN loading to the Bay could be achieved by eliminating fertilizer applied to the 7% of subwatersheds contributing the greatest fertilizer‐sourced TN loads to the Bay. These results indicate that management strategies aimed at decreasing loading from a small number of subwatersheds may be effective for reducing TN loads to the Bay, and similar analyses are possible in other watersheds.

Instructions for running the analytical code PAT (Purge Analyzer Tool) for computation of in-well time of travel of groundwater under pumping conditions

Released November 14, 2019 11:20 EST

2019, Open-File Report 2019-1104

P.T. Harte, B.J. Huffman, Tomas Perina, Herb Levine, Daewon Rojas-Mickelson


Understanding the optimal time needed to purge a well while pumping to collect a representative groundwater sample requires an understanding of groundwater flow in wells (in-well flow). Parameters that affect in-well flow include the hydraulic properties of the aquifer, well construction, drawdown from pumping, and pump rate. The time of travel relative to in-well flow is affected by the pump’s intake location. The Purge Analyzer Tool (PAT) incorporates hydraulic calculations to help assess the optimal purge times required to vertically transport groundwater in the well to the pump intake (Harte, 2017). Harte (2017) includes a discussion on the rationale for determining in-well groundwater flow and time of travel and also discusses the limitations inherent in the PAT; an understanding of the limitations is important to ensure proper use.

The PAT calculates flow by use of the Dupuit-Theim equation (Lohman, 1979) that assumes steady-state radial flow and a total inflow from the well opening or screen equal to the pumping rate (eq. 1). A bulk average hydraulic conductivity (Kavg) is derived from this relationship. Once Kavg is calculated, the program calculates incremental (layered) horizontal radial inflow into the well over user defined increments (layers). These defined increments represent the screen or well opening as a fraction of the total inflow. The amount of inflow per layer is proportional to the user-defined layered distribution of hydraulic conductivity (Klayer) because drawdown is assumed to be uniformly distributed in the well. The water budget equation that guides the solution of the PAT (eq. 1) is specified as:

Qp = Qv + QH + Qw                                     (1)


QP   is pumping rate,
Qv   is vertical flow entering the boundary of the mixing zone (Mz) from the summation of layered radial flow (∑Qhl-n) where l-n denotes number of layers,
QH   is horizontal radial flow into the mixing zone (Mz), and
Qw   is flow from wellbore storage effects.

The in-well flow is computed from the convergence of incremental (layered) radial inflows (Qhl-n) summed to the total vertical flow (QV) entering the adjacent zone to the pump intake (called mixing zone [Mz]) as shown in figure 1. The Qv is transported as one-dimensional piston flow. Within the Mz, it's assumed that flow to the pump is dominated by horizontal radial flow (QH) when the pump is in the open interval of the well. Flow from the wellbore storage (Qw) is computed from the volume of water pumped from the well at the time of the drawdown (s) measurement(s). Aquifer storage effects are unaccounted for but are likely to be problematic when (1) dewatering within the well opening occurs or (2) when the water table is close to the top of the well screen or open interval where additional flow into the upper portion of the well opening may occur. For fully saturated wells tens of feet below the water table, storage effects are likely to be more uniformly distributed across the well screen or open interval (regardless of confined or unconfined conditions). Therefore, radial inflow from storage will be less prominent under pump rates commonly used in groundwater sampling either for volumetric sampling (<3 gallons per minute) or low-flow sampling (<0.5 liters per minute).

A major benefit of the use of the PAT is the understanding of time-varying, vertical integration of captured pump water. The analytical model computes aquifer (formation) capture intervals relative to the open interval of the well. This information is displayed graphically (called aquifer fraction graphs) and can be used to assess the likely formation intervals contributing water to the sample at any time.

Adult monarch (Danaus plexippus) abundance is higher in burned sites than in grazed sites

Released November 14, 2019 09:06 EST

2019, Frontiers in Ecology and Evolution (7)

Julia B. Leone, Diane L. Larson, Jennifer L. Larson, Patrick Pennarola, Karen Oberhauser

Much of the remaining suitable habitat for monarchs (Danaus plexippus) in Minnesota is found in tallgrass prairies. We studied the association of adult monarch abundance with use of fire or grazing to manage prairies. Sites (n=20) ranged in size from 1 to 145 hectares and included land owned and managed by the Minnesota DNR, U.S. Fish and Wildlife Service, The Nature Conservancy, and private landowners. We measured Asclepias spp. (milkweeds, monarch host plants) and forb frequency in 0.5 x 2-m plots located along randomly-placed transects that were stratified to sample wet, mesic, and dry prairie types at each site. Adult butterfly surveys took place three times at each site during the summers of 2016 and 2017, using a standardized Pollard Walk (400 meters). Data were analyzed using mixed effects models. Monarchs were more abundant at sites managed with prescribed fire than with grazing. We found no difference in milkweed and forb frequency between burned and grazed prairies. There was no relationship between monarch abundance and the other predictor variables tested: milkweed frequency, site area, forb frequency, and percent prairie in a 1.5 km buffer area surrounding each site. Monarch abundance was lowest at grazed sites with high stocking rates. Our findings suggest that the use of burning or grazing for prairie management is not associated with milkweed or forb frequency, at least for sites that have not been burned in several years. They also suggest that heavy grazing may have negative impacts on monarchs.

Using the STARS model to evaluate the effects of the proposed action for the reinitiation of consultation on the coordinated long-term operation of the Central Valley and State Water Project

Released November 13, 2019 16:03 EST

2019, Open-File Report 2019-1125

Russell W. Perry, Adam C. Pope, Vamsi K. Sridharan

In 2016, the U.S. Bureau of Reclamation (USBR) and California Department of Water Resources requested a reinitiation of consultation under Section 7 of the Endangered Species Act on the coordinated long-term operations of the Central Valley and State Water Projects. This resulted in a Biological Assessment released by USBR in 2019. In its analysis of the Biological Assessment for its Biological Opinion on the proposed action, the National Marine Fisheries Service (NMFS) requested assistance from the U.S. Geological Survey to describe the effect of the proposed action on juvenile Chinook salmon (Oncorhynchus tshawytscha) populations migrating through the Sacramento-San Joaquin River Delta (henceforth called “the Delta”). Therefore, in this report we analyzed an 82-year time series of simulated river flows and Delta Cross Channel (DCC) gate operations under two scenarios constructed for the Biological Assessment: the proposed-action (PA) scenario and the continuing-operations scenario (COS).

To evaluate the proposed action, we used the STARS model (Survival, Travel time, And Routing Simulation model), a stochastic, individual-based simulation model designed to predict survival of a cohort of fish that experiences variable daily river flows as the fish migrate through the Delta. The STARS model uses parameter estimates from a Bayesian mark-recapture model that jointly estimates travel time and survival in eight discrete reaches of the Delta and migration routing at two key river junctions.

By applying the STARS model to the two 82-year scenarios, we found that the proposed action had negative effects on survival, travel time, and routing in October–December but positive effects in April–June. In October–December, there was a high probability that survival in the PA scenario was less than that in the COS, and that travel time and routing to the Interior Delta for the PA scenario was greater than that for the COS. The magnitude of the difference in survival between scenarios was larger in some years than in others. For example, we quantified that survival under the PA scenario was 10 percent lower than under the COS in 25 percent of the water years from October through December. During this period, inflow to the Delta tended to be lower under the PA scenario, and the DCC gate was open more frequently under the PA scenario than during the COS. Lower inflow reduces survival, and more frequent operation of the DCC gate 1) increases the proportion of fish entering the Interior Delta, where survival is low, and thus 2) reduces survival in the Sacramento River in reaches downstream of the DCC. In contrast, during the period April–June, survival was higher, travel times were lower, and routing to the Interior Delta was lower under the PA scenario relative to the COS, although the magnitude of the increase in survival was relatively small in most years (less than a 3-percent difference in survival). This difference between scenarios was driven by higher river flows in some years under the PA scenario relative to the COS. Overall, the differences in survival, travel time, and routing distance between the two operational scenarios were primarily driven by the timing and magnitude of the annual high river flows.

Wind sheltering impacts on land-atmosphere fluxes over fens

Released November 13, 2019 12:57 EST

2019, Frontiers in Environmental Science

Jessica Turner, Ankur R. Desai, Jonathan Thom, Kimberly P. Wickland, Brent Olson

Wetlands and their ability to mitigate climate change motivates restorative and protective action; however, scientific understanding of land-atmosphere interactions is restricted by our limited continuous observations of gaseous fluxes. Many wetlands are small in spatial scale and embedded in forested landscapes. Yet, little is known about how the relative sheltering of forests affects net carbon (C) and energy balance. Here, we analyze coterminous USGS and Ameriflux eddy covariance flux tower observations over three years in two shrub fens in Northern Wisconsin, one more sheltered (US-ALQ) than the other (US-Los). Unsurprisingly, the open site showed higher overall wind speeds. This should have implications for atmospheric fluxes in wetlands as wind-forced processes are essential in promoting gas exchange over water. While both sites had similar half-hourly net ecosystem exchange of CO2 (NEE) during daytime, there were significant differences in nighttime NEE, as well as in net radiation partitioning in early spring and late summer. Sensible heat (H) fluxes were smaller at the sheltered fen except for the months of July-September. In contrast, latent heat (LE) fluxes were higher in every month except July. Additionally, sheltered fen ecosystem respiration had a weaker linear correlation with air temperature (R: 0.08 versus 0.57 for the open fen). Our work suggests that canopy sheltering does not cause significant differences in half-hourly NEE during the day, but rather the largest differences such as lower CO2 emissions occur at nighttime due to higher variance at very low wind speeds. Sheltering also influenced direction of air flow, mean wind speeds in day versus night, energy balance, and sensible and latent heat fluxes. We discuss implications of these findings for wetland restoration.

Quality of surface water in Missouri, water year 2018

Released November 13, 2019 12:21 EST

2019, Data Series 1119

Robert T. Kay

The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, designed and operates a network of monitoring stations on streams and springs throughout Missouri known as the Ambient Water-Quality Monitoring Network. During water year 2018 (October 1, 2017, through September 30, 2018), water-quality data were collected at 76 stations: 74 Ambient Water-Quality Monitoring Network stations and 2 U.S. Geological Survey National Stream Quality Assessment Network stations. Among the 76 stations in this report, 4 stations have data presented from additional sampling performed in cooperation with the U.S. Army Corps of Engineers. Summaries of the concentrations of dissolved oxygen, specific conductance, water temperature, suspended solids, suspended sediment, Escherichia coli bacteria, fecal coliform bacteria, dissolved nitrate plus nitrite as nitrogen, total phosphorus, dissolved and total recoverable lead and zinc, and selected pesticide compounds are presented. Most of the stations have been classified based on the physiographic province or primary land use in the watershed monitored by the station. Some stations have been classified based on the unique hydrologic characteristics of the waterbodies (springs, large rivers) they monitor. A summary of hydrologic conditions including peak streamflows, monthly mean streamflows, and 7-day low flows also are presented for representative streamflow-gaging stations in the State.

Development of two quantitative PCR assays for detection of several Cottus species from environmental DNA in Pacific coast watersheds of North America

Released November 13, 2019 07:50 EST

2019, Conservation Genetics Resources

Marshal Hoy, Carl Ostberg

We developed two quantitative PCR assays for use with environmental DNA (eDNA) to detect numerous species in the genus Cottus that are indigenous to the Pacific coast watersheds of North America. We conducted in vitro assay validations on ten Cottus species and 32 potentially co-occurring non-Cottus species. We demonstrate the efficacy of these assays by field testing eDNA samples collected from streams inhabited by Cottus. These assays will be particularly useful for detecting Cottus in habitats where one (or more) of several Cottus species could be present.

Malignant melanoma of Brown Bullhead (Ameiurus nebulosus) in Lake Memphremagog, Vermont/Quebec

Released November 13, 2019 07:48 EST

2019, Journal of Fish Diseases

Vicki S. Blazer, Cassidy H. Shaw, Cheyenne R Smith, P Emerson, Thomas R. Jones

In 2012, brown bullhead (Ameiurus nebulosus) with large, raised, black growths were first reported from multiple areas within the Vermont portion of Lake Memphremagog. Subsequent surveys conducted from 2014-2017 at two sites within the lake indicated a prevalence of 30% in adult brown bullhead 200 mm and above total length. These lesions ranged from slightly raised smooth black areas to large, nodular areas on the body surface, fins and within the oral cavity. Microscopically these lesions were determined to be malignant melanoma with invasion into surrounding hypodermis, skeletal muscle and bone as well as metastases to gill, ovary and intestine. Liver neoplasms were also observed in 8% of the bullhead collected from Lake Memphremagog in 2015. Neither skin nor liver neoplasms were noted in Ticklenaked Pond, a site used for comparison.

Coastal marsh bird habitat selection and responses to Hurricane Sandy

Released November 12, 2019 16:14 EST

2019, Wetlands

Allison Benscoter, James Beerens, Stephanie Romanach

Wetlands provide numerous ecosystem functions such as water purification, nutrient cycling, and wildlife habitat. Avian populations are indicators of wetland health, and understanding their responses to extreme events can aid in targeting restoration efforts following disturbance. Here, we assessed the habitat selection of six coastal wetland bird species (American Bittern, Black-crowned Night Heron, Great Egret, Glossy Ibis, Snowy Egret, Yellow-crowned Night Heron) related to an extreme weather event, Hurricane Sandy. We used Discrete Choice Resource Selection Functions to estimate habitat selection. Results showed species probability of use increased with lower elevation and slope, and closer proximity to marsh, salt marsh, Phragmites, and protected areas. Estimates of marsh dieback from Hurricane Sandy occurred disproportionately in areas with higher probability of species use. Species were observed farther from the coast and at higher elevations in the four breeding seasons after (2013–2016) compared to before (2000–2012) Hurricane Sandy. Our results indicate that although high suitability areas were affected by the storm, these six wetland bird species may have responded by moving inland and to higher elevation. Understanding how coastal wetland birds respond to storm events is important for conservation planning, particularly as storm frequency is projected to increase in the future.

Geologic field photograph map of the Grand Canyon region, 1967–2010

Released November 12, 2019 13:02 EST

2019, General Information Product 189

George H. Billingsley, Gregory Goodwin, Sarah E. Nagorsen, Monica E. Erdman, Jason T. Sherba

The Grand Canyon geologic field photograph collection contains 1,211 geotagged photographs collected during 43 years of geologic mapping from 1967 to 2010. The photographs document some key geologic features, structures, and rock unit relations that were used to compile nine geologic maps of the Grand Canyon region published at 1:100,000 scale, and many more maps published at 1:24,000 scale. Metadata for each photograph include description, date captured, coordinates, and a keyword system that places each photograph in one or more of the following categories: arches and windows, breccia pipes and collapse structures, faults and folds, igneous rocks, landslides and rockfalls, metamorphic rocks, sedimentary rocks, sinkholes, and springs and waterfalls. Original photograph slides are available at the Northern Arizona University Cline Library Special Collections and Archives.

The Geologic Field Photograph Map of the Grand Canyon Region, 1967–2010, is an interactive online map application that shows clusters of photograph thumbnails and popup windows that scale as users pan, zoom, and click around the map. The photographs can be filtered by category, searched based on date range, description, and keywords, and (or) downloaded. All information populated within the map is served from a ScienceBase record of the Grand Canyon field photograph collection that can be accessed at https://doi.org/10.5066/F7WS8SHW.

Standardized IMGT nomenclature of salmonidae IGH genes, the paradigm of Atlantic salmon and rainbow trout: From genomics to repertoires

Released November 12, 2019 07:56 EST

2019, Frontiers in Immunology (10)

Susana Magadan, Aleksei Krasnov, Saida Hadi-Saljoki, Sergey Afanasyev, Stanislas Mondot, Rosario Castro, Irene Salinas, Oriol Sunyer, John Hansen, Ben F Koop, Marie-Paule Lefranc, Pierre Boudinot

In teleost fish as in mammals, humoral adaptive immunity is based on B lymphocytes expressing highly diverse immunoglobulins (IG). During B cell differentiation, IG loci are subjected to genomic rearrangements of V, D, and J genes, producing a unique antigen receptor expressed on the surface of each lymphocyte. During the course of an immune response to infections or immunizations, B cell clones specific of epitopes from the immunogen are expanded and activated, leading to production of specific antibodies. Among teleost fish, salmonids comprise key species for aquaculture. Rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar) are especially important from a commercial point of view and have emerged as critical models for fish immunology. The growing interest to capture accurate and comprehensive antibody responses against common pathogens and vaccines has resulted in recent efforts to sequence the IG repertoire in these species. In this context, a unified and standardized nomenclature of salmonid IG heavy chain (IGH) genes is urgently required, to improve accuracy of annotation of adaptive immune receptor repertoire dataset generated by high-throughput sequencing (AIRRseq) and facilitate comparisons between studies and species. Interestingly, the assembly of salmonids IGH genomic sequences is challenging due to the presence of two large size duplicated IGH loci and high numbers of IG genes and pseudogenes. We used data available for Atlantic salmon to establish an IMGT standardized nomenclature of IGH genes in this species and then applied the IMGT rules to the rainbow trout IGH loci to set up a nomenclature, which takes into account the specificities of Salmonid loci. This unique, consistent nomenclature for Salmonid IGH genes was then used to construct IMGT sequence reference directories allowing accurate annotation of AIRRseq data. The complex issues raised by the genetic diversity of salmon and trout strains are discussed in the context of IG repertoire annotation.

The importance of natural versus human factors for ecological conditions of streams and rivers

Released November 12, 2019 07:45 EST

2019, Science of the Total Environment

Tao Tang, R. Jan Stevenson, James Grace

Streams are influenced by watershed-scale factors, such as climate, geology, topography, hydrology, and soils, which mostly vary naturally among sites, as well as human factors, agriculture and urban development. Thus, natural factors could complicate assessment of human disturbance. In the present study, we use structural equation modeling and data from the 2008-2009 United States National Rivers and Streams Assessment to quantify the relative importance of watershed-scale natural and human factors for in-stream conditions. We hypothesized that biological condition, represented using a diatom multimetric index (MMI), is directly affected by in-stream physicochemical environment, which in turn is regulated by natural and human factors. We evaluated this hypothesis at both national and ecoregion scales to understand how influences vary among regions. We found that direct influences of in-stream environment on diatom MMIs were greater than natural and human factors at the national scale and in all but one ecoregion. Meanwhile, in-stream environments were jointly explained by natural variations in precipitation, base flow index, hydrological stability, % volcanic rock, soil water table depth, and soil depth and by human factors measured as % crops, % other agriculture, and % urban land use. The explained variance of in-stream environment by natural and human factors ranged from 0.30 to 0.75, for which natural factors independently accounted for the largest proportion of explained variance at the national scale and in seven ecoregions. Covariation between natural and human factors accounted for a higher proportion of explained variance of in-stream environment than unique effects of human factors in most ecoregions. Ecoregions with relatively weak effects by human factors had relatively high levels of covariance, high levels of human disturbance, or small ranges in human disturbance. We conclude that accounting for effects of natural factors and their covariation with human factors will be important for accurate ecological assessments.

Seasonal epilimnetic temperature patterns and trends in a suite of lakes from Wisconsin (USA), Germany and Finland

Released November 11, 2019 13:49 EST

2019, Inland Waters (9) 471-488

Richard C. Lathrop, Peter Kasprzak, Marjo Tarvainen, Anne-Mari Ventela, Tapio Keskinen, Rainer Koschel, Dale M. Robertson

Epilimnetic temperatures from the early 1980s through 2017 were analyzed for 12 Wisconsin, German and Finnish lakes. Seasonal temperature metrics exhibited large interannual variability with trends differing among regions. In the Wisconsin lakes, only late summer and fall temperatures increased significantly. In the northeastern Germany lakes, temperatures increased in all seasons, but only significantly for some metrics. The Finnish lakes, which spanned the country’s latitude range, exhibited large spring temperature increases influenced by earlier ice-out; summer temperatures also increased significantly, but fall changes were varied. To elucidate longer-term epilimnetic temperature patterns, earlier records from 4 lakes were analyzed. For Lake Mendota (southern Wisconsin), spring and late fall temperatures increased modestly but significantly since 1894; summer temperatures also increased modestly due to a higher frequency of recent summers with warm temperatures and not from new record high temperatures. Trout Lake (northern Wisconsin) exhibited warm temperatures in some summers during the 1930s-1940s similar to warm temperatures in some recent summers. Air-water temperature relationships coupled with long-term regional air temperature data also indicated summer epilimnetic temperatures in the study lakes were likely as warm in the 1930s-1940s as in recent years. Lake data confirmed cooler epilimnetic temperatures occurred in many summers during the 1950s-1980s coincident with intervening cooler air temperatures during this period. Because epilimnetic temperatures have not increased monotonically since 1900, our study supports continued temperature monitoring in lakes with extensive historical data to better understand and project future effects of climate change on lake ecosystems.

The complexity of mudstone diagenesis - some insight from the Tøyen Formation, Lower to Middle Ordovician, southern Sweden

Released November 09, 2019 19:16 EST

2019, GFF (141) 54-67

Sven Egenhoff, Neil Fishman, Heather A. Lowers, Per Ahlberg

The Lower to Middle Ordovician Tøyen Shale in southern Sweden, a biostratigraphically well-dated siliciclastic mudstone unit, shows 18 distinct authigenic cements that include sulfides, carbonates, silicates, clays, and phosphates. Marcasite, sphalerite, galena, and six texturally distinct types of pyrite characterize the sulfides whereas only one type of dolomite and three different generations of calcite are observed in this unit. Quartz, phosphate, and organic matter occur as only one generation each. Authigenic clay minerals are represented by chlorite and kaolinite. The paragenetic sequence of cements is subdivided into the two pre-burial carbonates, succeeded by ten relatively early burial cements, and six late burial cements, the kaolinite being the latest of them all and potentially being of Cretaceous age. Based on textural relationships, the paragenetic sequence of alterations started with dolomite precipitation followed by calcite, and then five different generations of pyrite. All eleven other phases post-date these initial seven cements in the Tøyen Shale.

Temporal variation in genetic structure within the threatened spectacled eider

Released November 09, 2019 12:52 EST

2019, Conservation Genetics

Sarah A. Sonsthagen, Christy Haughey, Matthew G. Sexson, Diana V Solovyeva, Margaret R. Petersen, Abby Powell

We examined the genetic structure of the threatened spectacled eider 14–18 years after the initial assessment to evaluate the influence of population recovery on diversity. Concordant with the initial assessment, spectacled eiders were highly structured at mitochondrial (mt) DNA and lacked differentiation at microsatellite loci. The degree and spatial pattern of structure has changed at mtDNA; a 33.0–40.3% reduction in overall FST and ΦST, respectively, and a marked reduction in pairwise FST (-83.1 to -91.4%) among Alaska sites. Reduction in genetic structure is suggestive of increased female dispersal within Alaska. These findings highlight the importance of reevaluating genetic diversity as species recover from declines as microevolutionary and demographic processes are dynamic and continually shape associations among populations.

Simple metrics predict salt-marsh sediment fluxes

Released November 09, 2019 08:35 EST

2019, Geophysical Research Letters (46) 12250-12257

Daniel J. Nowacki, Neil Kamal Ganju

The growth (or decay) of salt marshes depends on suspended-sediment flux into and out of the marsh. Suspended-sediment concentration (SSC) is a key element of the flux, and SSC-based metrics reflect the long-term sediment-flux trajectories of a variety of salt marshes. One metric, the flood–ebb SSC differential, correlates with area-normalized sediment flux and can indicate salt-marsh resilience over months to years. We hypothesize that these metrics may be relevant over shorter time periods. With data from 13 salt-marsh channels, we show that sediment flux direction and magnitude can be inferred from SSC differential over a wide range of timescales. Furthermore, in settings characterized by a standing tidal wave, the water-level gradient can be used instead of velocity to compute the SSC differential, enabling less-intensive measurements that capture fundamental sediment-flux parameters. Distilling the sediment-flux trajectory into simple metrics improves sediment-budget assessment, drives geomorphic model development, and clarifies field observations.

Naturally occurring uranium in groundwater in northeastern Washington State

Released November 08, 2019 12:31 EST

2019, Fact Sheet 2019-3069

Sue C. Kahle

Uranium is a radioactive element (radionuclide) that occurs naturally in rock, soil, and water, usually in low concentrations. Radionuclides are unstable atoms with excess energy and as radionuclides decay, they emit radiation. The uranium decay sequence also includes other radionuclides of concern such as radium and radon. This fact sheet addresses naturally occurring uranium in groundwater in northeastern Washington.

Batrachochytrium salamandriovrans (Bsal) in Appalachia—Using scenario building to proactively prepare for a wildlife disease outbreak caused by an invasive amphibian chytrid fungus

Released November 08, 2019 10:35 EST

2018, Open-File Report 2018-1150

M.C. Hopkins, M.J. Adams, P.E. Super, D.H. Olson, C.R. Hickman, P. English, L. Sprague, I.B. Maska, A.B. Pennaz, K.A. Ludwig

Batrachochytrium salamandrivorans (Bsal), a pathogenic chytrid fungus, is nonnative to the United States and poses a disease threat to vulnerable amphibian hosts. The Bsal fungus may lead to increases in threatened, endangered, and sensitive status listings at State, Tribal, and Federal levels, resulting in financial costs associated with implementing the Endangered Species Act of 1973. The United States is a global biodiversity hotspot for salamanders, an order of amphibians that is particularly vulnerable to developing a disease called chytridiomycosis when exposed to Bsal. Published Bsal risk assessments for North America have suggested that salamanders within the Appalachian region of the United States are at a high risk. In May 2017, a workshop was facilitated by the Department of the Interior’s Strategic Sciences Group. During the workshop, a discussion-based incident-response exercise focused on a hypothetical Bsal disease outbreak in Appalachia was led by U.S. Geological Survey staff members. Participants included representatives of the Eastern Band of the Cherokee Indians, U.S. Fish and Wildlife Service, National Park Service, Appalachian Landscape Conservation Cooperative, Tennessee Wildlife Resources Agency, and U.S. Department of Agriculture’s U.S. Forest Service. Scenario building was used to brainstorm cascading consequences (social, economic, and ecological) of a Bsal disease outbreak in the Appalachian region. This report highlights the management and science actions that could be undertaken to ensure an effective, rapid response to a Bsal introduction into the United States.

Geology and assessment of undiscovered oil and gas resources of the Lomonosov-Makarov Province, 2008

Released November 08, 2019 09:16 EST

2019, Professional Paper 1824-CC

Thomas E. Moore, Kenneth J. Bird, Janet K. Pitman

Thomas E. Moore, Donald L. Gautier, editor(s)

The Lomonosov-Makarov Province lies in the central Arctic Ocean and encompasses the northern part of the oceanic Amerasia Basin (Makarov and Podvodnikov Basins) and the adjoining Lomonosov Ridge and Siberian continental margins. The Amerasia Basin is thought to have been created in the Jurassic and Early Cretaceous by rotational rifting of the Alaska-Siberia margin away from the Canada margin about a pivot point in the Mackenzie Delta and an associated continental-scale transform fault along the Lomonosov Ridge. The province is bounded on the south by the Cretaceous Alpha-Mendeleev Ridge, an undersea ridge composed of plume-type volcanic rocks that obliquely crosses the Amerasia Basin, dividing it into northern and southern parts. The thickest passive-margin succession in the province lies along the Siberian margin, where sediments thin from a maximum thickness along the continental margin to less than 2 km in the basin. The northern part of the province consists of the Lomonosov Ridge, which was rifted away from the Eurasia Plate in the Paleocene during formation of the oceanic Eurasia Basin, creating an isolated, narrow, submerged, but high-standing microcontinent. This part of the province contains sediments that were shed from the Eurasia Plate in the Mesozoic and covered by pelagic and hemipelagic sediments in the Cenozoic, creating depositional successions with thicknesses ranging from about 1 to more than 5 km.

This tectonic framework provides the basis for division of the province into four assessment units (AUs), including (1) Lomonosov Ridge AU, (2) Makarov Basin Margin AU, (3) Siberian Passive Margin AU, and (4) Makarov Basin AU. The Lomonosov Ridge and Makarov Basin Margin AUs compose a displaced part of the Cretaceous shelf and slope, respectively, of the Eurasia continental margin with a covering drape of pelagic Cenozoic sediments. The Siberian Passive Margin and Makarov Basin AUs represent the slope of the Siberian continental margin and adjoining basin plain deposits, respectively, deposited on oceanic crust of the northern Amerasia Basin. All of the AUs are entirely submarine and covered by the polar icecap, and consequently have not been explored for petroleum. Petroleum source rock units considered in the assessment of the province are mostly hypothetical, and include Triassic and Jurassic platformal marine shale units on the Lomonosov Ridge, and province-wide Lower Cretaceous synrift, Lower and Upper Cretaceous postrift, and Paleogene organic-rich shale intervals. The most prospective reservoirs and traps are envisioned to include base-of-slope turbidite-fan complexes, slope channels and basins, extensional and growth fault structures, and other stratigraphic, structural, and composite trap features typically present on clastic-dominated continental passive margins. Because of concerns about reservoir quality in the Makarov Basin AU and the detrimental effect of Paleocene rifting in the Lomonosov Ridge AU, these units were not quantitatively assessed, as they were judged to have less than 10 percent probability of containing at least one accumulation of hydrocarbons equal to or greater than 50 million barrels of oil equivalent (MMBOE). The mean volumes of undiscovered resources for the Makarov Basin Margin AU are estimated to be 0.12 billion barrels of oil and 0.74 trillion cubic feet of nonassociated gas, whereas the undiscovered resources for the Siberian Passive Margin AU are estimated to be ~1 billion barrels of oil and 4.7 trillion cubic feet of nonassociated gas.

Full Equations Model Graphical Data Inspector (FEQ–GDI) user guide

Released November 07, 2019 15:32 EST

2019, Open-File Report 2019-1113

Jessica L. Ern, Terry Ortel, Audrey L. Ishii, Maitreyee Bera

The Full Equations Model Graphical Data Inspector (FEQ–GDI) is a menu-driven utility program that enables users to visualize and check the geometric and hydraulic properties of channel cross sections, selected control structures, and stream profiles in the input files for the Full Equations (FEQ) Model and the Full Equations Utilities (FEQUTL) Model. The FEQ Model is a computer program for the simulation of one-dimensional, unsteady flow in open channels and through control structures using the full, dynamic equations of motion. The input to FEQ Model includes the output from the FEQUTL Model, which computes tables relating the hydraulic properties of channel cross sections and control structures to depth, flow, and (or) other specified parameters. FEQ–GDI can be used to help users quickly detect anomalies in the data that may indicate errors in the input files.

Detailed Lithologic Logs from Auger Holes in southern Charleston County, southwestern Dorchester County, and eastern Colleton County, South Carolina

Released November 07, 2019 13:30 EST

2019, Open-File Report 2019-1119

Robert E. Weems, William C. Lewis

The lithologic logs described in this open-file report are from holes augered in the South Carolina Low Country in parts of Charleston, Dorchester, and Colleton Counties from 1998 through 2010. Lithologic units described here include not only surficial Pleistocene units but also subsurface stratigraphic units ranging as far back in age as late Eocene. This region comprises the southernmost and westernmost portions of the area included in the 1:100,000 Charleston region geologic map, which lies east of 80°30′ west and south of 33°15′ north. Logs of the remainder of that map area were published prior to the release of that map. The present report completes the lithologic log record from which the 1:100,000 Charleston region geologic map largely was compiled.

Nutritional physiology of honey bee (Apis mellifera L.) workers across an agricultural land-use gradient

Released November 07, 2019 10:20 EST

2019, Scientific Reports (7)

Matthew Smart, Clint R. V. Otto, Jonathan G Lundgren

Land use and habitat quality have emerged as critical factors influencing the health, productivity, and survival of honey bee colonies. However, characterization of the mechanistic relationship between differential land-use conditions and ultimate outcomes for honey bee colonies has been elusive. We assessed the physiological health of individual worker honey bees in colonies stationed across a gradient of agricultural land use to ask whether indicators of nutritional physiology including glycogen, total sugar, lipids, and protein were associated with land-use conditions over the growing season and colony population size the subsequent spring during almond pollination. Across the observed land-use gradient, we found that September lipid levels related to growing-season land use, with honey bees from apiaries surrounded by more favorable land covers such as grassland, pasture, conservation land, and fallow fields having greater lipid reserves. Further, we observed a significant effect of total protein during September on population size of colonies during almond pollination the following February. We demonstrate and discuss the utility of quantifying nutritional biomarkers to infer land-use quality and predict colony population size.

Protracted multipulse emplacement of a post-resurgent pluton: The case of Platoro caldera complex (Southern Rocky Mountain volcanic field, Colorado)

Released November 07, 2019 06:44 EST

2019, Geochemistry, Geophysics, Geosystems

Filip Tomek, Amy Gilmer, M. S. Petronis, Peter W. Lipman, M. S. Foucher

Many eroded calderas expose associated postcollapse plutons, but detailed fieldwork‐supported studies have rarely focused on the internal structure that can contribute to understanding of emplacement dynamics. The Alamosa River monzonite pluton is a postcollapse intrusion at the Platoro caldera complex that erupted six large ignimbrites between 30.2 and 28.8 Ma in the Southern Rocky Mountains volcanic field. Magnetic fabrics in this intrusion indicate the pulsed emplacement of a vertically extensive pluton. The magmatic pulses are documented by three concentric domains of magnetic foliations elongated in ~NE‐SW direction, corresponding to structural trends at the Platoro caldera complex and preexisting regional structures. As no evidence for deformation of wall rocks and the adjacent resurgent block has been identified, we interpret the Alamosa River pluton as a postresurgent intrusion. The space‐opening process involved magmatic stoping and small‐scale magma wedging. New SHRIMP‐RG U/Pb zircon dates (28.98 ±0.18, 27.42 ± 0.35, and 27.32 ± 0.38 Ma) suggest a magmatic lifespan of ~1.7 My for the Alamosa River pluton. Our results indicate that postcaldera magmatism includes pulsed and protracted activity from large intracaldera resurgent plutons to smaller postresurgent stocks and sheeted complexes. As demonstrated by the Alamosa River pluton, some intrusions are emplaced shortly after collapse and resurgence, but postcaldera volcano‐plutonic systems may remain active for several million years or more. We also suggest that subvolcanic magma bodies may be assembled incrementally and that the record of early composite magma lenses preserved as magma wedges are later obliterated by convective flowage and crystallization.

Petroleum hydrocarbons in semipermeable membrane devices deployed in the Northern Gulf of Mexico and Florida keys following the Deepwater Horizon incident

Released November 06, 2019 16:03 EST

2019, Marine Pollution Bulletin

Timothy Bargar, David Alvarez, Scott A. Stout

The Deepwater Horizon (DWH) oil spill from April to July of 2010 contaminated Gulf of Mexico waters through release of an estimated 4.1 × 106 barrels of oil. Beginning in June of 2010, semipermeable membrane devices (SPMDs) were deployed near areas with sensitive marine habitats (Alabama Alps and Western Shelf) potentially exposed to that oil. Elevated TPAH50 concentrations, flux rates and similarity of histograms and diagnostic ratios for polycyclic aromatic hydrocarbons (PAH) from SPMDs to weathered floating oil collected during the DWH spill indicates the Alabama Alps habitats were affected. While not affected by oil from the DWH spill, the temporal pattern of PAH contamination of SPMDs deployed near the Western Shelf between July 2010 and March 2011 could indicate prevailing currents affected contaminant transport to the Western Shelf Area (East and West Flower Garden, Sonnier, and Stetson Banks) from non-DWH sources, including oil and gas exploration, shipping, and Mississippi River effluent.

Phytoplankton community and algal toxicity at a recurring bloom in Sullivan Bay, Kabetogama Lake, Minnesota, USA

Released November 06, 2019 12:41 EST

2019, Scientific Reports (9)

Victoria Christensen, Ryan P. Maki, Erin Stelzer, Jack E. Norland, Eakalak Khan

Kabetogama Lake in Voyageurs National Park, Minnesota, USA suffers from recurring late summer algal blooms that often contain toxin-producing cyanobacteria. Previous research identified the toxin microcystin in blooms, but we wanted to better understand how the algal and cyanobacterial community changed throughout an open water season and how changes in community structure were related to toxin production. Therefore, we sampled one recurring bloom location throughout the entire open water season. The uniqueness of this study is the absence of urban and agricultural nutrient sources, the remote location, and the collection of samples before any visible blooms were present. Through quantitative polymerase chain reaction (qPCR), we discovered that toxin-forming cyanobacteria were present before visible blooms and toxins not previously detected in this region (anatoxin-a and saxitoxin) were present, indicating that sampling for additional toxins and sampling earlier in the season may be necessary to assess ecosystems and human health risk.

Updates to the Madison Lake (Minnesota) CE–QUAL–W2 water-quality model for assessing algal community dynamics

Released November 06, 2019 10:02 EST

2019, Scientific Investigations Report 2019-5124

Erik A. Smith, Richard L. Kiesling

A previously developed CE–QUAL–W2 model for Madison Lake, Minnesota, simulated the algal community dynamics, water quality, and fish habitat suitability of Madison Lake under recent (2014) meteorological conditions. Additionally, this previously developed model simulated the complex interplay between external nutrient loading, internal nutrient loading from sediment release of phosphorus, and the organic matter decomposition of the algal biomass. However, the partitioning of Cyanophyta within the modeling framework was simplified to one group and did not account for how different Cyanophyta populations are affected by light conditions, use of nitrogen, temperature growth ranges, and differences in settling rates. Properly capturing Cyanophyta dynamics is important given the potential risks posed by potential large algal blooms. For example, when Cyanophyta form large blooms, recreational activities can become restricted in certain areas because of thick algal scums or algal mats, in addition to the possible production of a class of toxins, known as cyanotoxins, capable of threatening human health, domestic animals, and wildlife. Therefore, we updated the model to partition the Cyanophyta into a group that fixed nitrogen and a second, more buoyant Cyanophyta group that did not independently fix nitrogen.

The U.S. Geological Survey, in cooperation with the St. Croix Watershed Research Station (Science Museum of Minnesota) with support from the Environmental and Natural Resources Trust Fund of Minnesota (Legislative-Citizen Commission on Minnesota Resources), updated the Madison Lake CE–QUAL–W2 model to address the shortcomings of simulating Cyanophyta in the previously developed model and better characterize Cyanophyta into two groups. In addition to updating the Cyanophyta group differentiation, the part of the model that handles the simulation of algal community dynamics was updated while preserving model predictive capabilities for nutrients, water temperature, and dissolved oxygen. The calibration and validation of the model was done under recent meteorological conditions with large and persistent Cyanophyta blooms (2014 and 2016).

Overall, the model simulations predicted the persistently large total phosphorus concentrations in the hypolimnion of Madison Lake and key differences in nutrient concentrations between 2014 and 2016. The Cyanophyta bloom persistence throughout the summer was also simulated by the model in 2014 and 2016, a critical goal of the model update. Finally, monthly total phosphorus budgets were calculated for the updated Madison Lake model for 2014 and 2016.

The lava flow that came to Hilo—The 1880–81 eruption of Mauna Loa volcano, Island of Hawai‘i

Released November 06, 2019 09:58 EST

2019, Scientific Investigations Report 2019-5129

James P. Kauahikaua, Ben Gaddis, Ku`ulei Kanahele, Ken Hon, Valerie Wasser

The Mauna Loa eruption sequence of 1880–81 consists of two eruptions. The May 1880 eruption in Mokuʻāweoweo at the summit of Mauna Loa lasted just a few days and was followed 6 months later by three lava flows that issued from vents along the Northeast Rift Zone. The November 1880 eruption lasted almost a year and one of its flows nearly reached Hilo Bay.

Public reaction in Hilo to the advancing lava flow increased as the lava got closer, but a smallpox quarantine prevented travelers and government officials from leaving Honolulu, the government seat of the Hawaiian Kingdom, until July 1881. In the King’s absence, his sister Princess Regent Liliʻuokalani and key officials met in Hilo at the beginning of August to plan a government response. This included the first known plan to use barriers and explosives to divert the lava flow in Hawaiʻi. Fortunately, the lava flow stopped before the plan was enacted; however, both Christian prayer and traditional Hawaiian chants and gifts to the Hawaiian deity Pele were offered in the last few weeks of lava activity.

Mauna Loa was again restless in 2019 and the time seems optimum to review this and other Mauna Loa flows, in order to be ready for the next lava flow. Should the next flow threaten developed areas, review of past lava flow threats may provide valuable experience on how the public may best be provided with information.

Near-field receiving-water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California—2018

Released November 06, 2019 09:48 EST

2019, Open-File Report 2019-1084

Daniel J. Cain, Janet K. Thompson, Francis Parchaso, Sarah Pearson, Robin Stewart, Matthew A. Turner, Kelly H. Shrader, Emily L. Zierdt Smith, Samuel N. Luoma

Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in south San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2018 to December 2018. These append to long-term datasets extending back to 1974. A major focus of the report is an integrated description of the 2018 data within the context of the longer, multi-decadal dataset. This dataset supports the City of Palo Alto’s Near-Field Receiving-Water Monitoring Program, initiated in 1994.

Significant reductions in silver and copper concentrations in both sediment and M. petalum occurred at the site in the 1980s following the implementation by PARWQCP of advanced wastewater treatment and source control measures. Since the 1990s, concentrations of these elements appear to have stabilized at concentrations somewhat above (silver [Ag]) or near (copper [Cu]) regional background concentrations. Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2018, concentrations of silver and copper in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se, were generally similar in timing and magnitude as those for Ag and Cu. This record suggests that legacy contamination and regional-scale factors now largely control sedimentary and bioavailable concentrations of silver and copper, as well as other elements of regulatory interest, at the Palo Alto site.