| Abstract: | During the 20th century, there have been large-scale anthropogenic modifications to the South Florida ecosystem. The effects of these changes on Florida Bay and its biological communities are currently of political and scientific interest. This study is part of a larger effort to reconstruct the history of environmental changes in the bay, using paleoecological techniques. We are using diatom indicators preserved in Florida Bay sediments to infer long-term water quality, productivity, nutrient, and salinity changes. We are also obtaining information concerning the natural variability of the ecosystem.
Diatoms are microscopic algae, the remains of which are generally well preserved in sediments, and their distributions are closely linked to water quality. Diatoms were extracted from a 70-cm sediment core collected from the Pass Key mudbank of Florida Bay by the U.S. Geological Survey. Between 300-500 diatom valves from each of 15 core samples were identified and counted. Estimates of absolute abundance, species richness, Shannon-Wiener diversity, and centric:pennate ratios were calculated for each sample that was counted. Information on the ecology of the diatom species is presented, and changes in diatom community composition are evaluated.
Samples contained an average of four million diatom valves per gram of sediment. Major changes in the diatom community are evident down core. These include increases in the percent abundance of marine diatoms in the time period represented by the core, probably the result of increasing salinity at Pass Key. Benthic diatoms become less abundant in the top half of the core. This may be related to a number of factors including the die-off of sea grass beds or increased turbidity of the water column.
Once the chronology of the Pass Key core 37 is established, these down-core changes can be related to historical events and compared with other indicators in the sedimentary record that are currently being investigated by U.S Geological Survey researchers.
This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. |
| Genre: | USGS Numbered Series |
| ProdID: | 24265 |
| Citation Author: | Pyle, Laura; Cooper, S. R.; Huvane, J. K. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | - |
| Citation Editor: | |
| Citation End Page: | |
| Citation Issue: | |
| Citation Keywords: | |
| Citation Language: | ENGLISH |
| Citation Larger Work Title: | |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | 37 p. :ill., map ;28 cm. |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | U.S. Geological Survey, |
| Citation Series: | Open-File Report |
| Citation Series Code: | OFR |
| Citation Series Number: | 98-522 |
| Citation Search Results Text: | Diatom paleoecology Pass Key core 37, Everglades National Park, Florida Bay; 1998; OFR; 98-522; Pyle, Laura; Cooper, S. R.; Huvane, J. K. |
| Citation Start Page: | |
| Citation Volume: | |
| Citation Year: | 1998 |
| Type: | citation/reference |
| Text: | Diatom paleoecology Pass Key core 37, Everglades National Park, Florida Bay; 1998; OFR; 98-522; Pyle, Laura; Cooper, S. R.; Huvane, J. K. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/usgs_thumb.jpg |
| URL (INDEX PAGE): | http://pubs.usgs.gov/pdf/of/ofr98522.html |
| Date Other: | Tue, 1 Jun 1999 00:00 -0500 |
| Publisher: | U.S. Geological Survey, |
