Golden alga presence and abundance are inversely related to salinity in a high-salinity river ecosystem, Pecos River, USA

Harmful Algae
By: , and 



Prymnesium parvum (golden alga, GA) is a toxigenic harmful alga native to marine ecosystems that has also affected brackish inland waters. The first toxic bloom of GA in the western hemisphere occurred in the Pecos River, one of the saltiest rivers in North America. Environmental factors (water quality) associated with GA occurrence in this basin, however, have not been examined. Water quality and GA presence and abundance were determined at eight sites in the Pecos River basin with or without prior history of toxic blooms. Sampling was conducted monthly from January 2012 to July 2013. Specific conductance (salinity) varied spatiotemporally between 4408 and 73,786 mS/cm. Results of graphical, principal component (PCA), and zero-inflated Poisson (ZIP) regression analyses indicated that the incidence and abundance of GA are reduced as salinity increases spatiotemporally. LOWESS regression and correlation analyses of archived data for specific conductance and GA abundance at one of the study sites retrospectively confirmed the negative association between these variables. Results of PCA also suggested that at <15,000 mS/cm, GA was present at a relatively wide range of nutrient (nitrogen and phosphorus) concentrations whereas at higher salinity, GA was observed only at mid-to-high nutrient levels. Generally consistent with earlier studies, results of ZIP regression indicated that GA presence is positively associated with organic phosphorus and in samples where GA is present, GA abundance is positively associated with organic nitrogen and negatively associated with inorganic nitrogen. This is the first report of an inverse relation between salinity and GA presence and abundance in riverine waters and of interaction effects of salinity and nutrients in the field. These observations contribute to a more complete understanding of environmental conditions that influence GA distribution in inland waters.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Golden alga presence and abundance are inversely related to salinity in a high-salinity river ecosystem, Pecos River, USA
Series title Harmful Algae
DOI 10.1016/j.hal.2014.06.012
Volume 39
Issue 2014
Year Published 2014
Language English
Publisher Elsevier Science BV
Publisher location Amsterdam
Contributing office(s) Coop Res Unit Atlanta
Description 11 p.
First page 81
Last page 91
Time Range Start 2012-01-01
Time Range End 2013-07-31
Country United States
State New Mexico, Texas
Other Geospatial Pecos River
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
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