Abstract
Nitrogen (N) deposition has been implicated in changes in surface water chemistry and algal composition in several dilute mountain lakes of the western United States. Lakes of the Snowy Range (Medicine Bow National Forest, Wyoming) appear to have low nitrate concentrations currently, and 2 Snowy Range lakes showed strong eutrophication responses to N or N + phosphorus (P) additions in previous enclosure experiments. In this study, we explored the regional extent of phytoplankton N limitation by examining a nutrient ratio index (dissolved inorganic nitrogen:total phosphorus) and phytoplankton species-environment relationships across 15 Snowy Range lakes. Based on this index, we estimate that phytoplankton biomass in the study lakes is largely N limited or N + P colimited. In addition, redundancy analysis demonstrated strong relationships between phytoplankton species composition and N gradients, with chrysophyte taxa favored in low-N lakes and cyanophytes and chlorophytes favored in higher-N lakes. We conclude that both phytoplankton biomass and community structure are sensitive indicators of N gradients in lakes of the Snowy Range, and that eutrophication responses to future increases in N loading could be widespread in these and other low-N lakes.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
