Do Phosphorus and Nitrogen Act Synergistically to Exacerbate Algal Growth and Eutrophication
Location
Eccles Conference Center Auditorium
Event Website
http://water.usu.edu
Start Date
3-31-2015 12:40 PM
End Date
3-31-2015 12:50 PM
Description
Phosphorus and nitrogen cause algal blooms that decrease water quality of lakes, rivers and coastal ecosystems. Although phosphorus control has frequently been implemented to reduce eutrophication, several lines of evidence indicate that nitrogen also needs to be controlled in some situations. Whole-lake experiments, and a correlation analysis of N, P, and chlorophyll in 1268 US lakes all indicate that nitrogen and phosphorus together produce larger algal blooms than do addition of each nutrient alone. Nitrogen fixation by cyanobacteria may alleviate nitrogen deficiencies in some cases, but ecological constraints on this process, coupled with high levels of denitrification, can lead to co-limitation by both nutrients. Although a phosphorus-only explanation for algal blooms has persisted for decades, this misinterpretation has impeded efforts to understand how nitrogen and phosphorus can both influence algal communities. Nutrient controls at watershed scales are further complicated because controlling only one nutrient in upstream areas results in export of the other damaging nutrient downstream to coastal areas. Additional research is needed to understand when and where joint controls are necessary to control eutrophication.
Do Phosphorus and Nitrogen Act Synergistically to Exacerbate Algal Growth and Eutrophication
Eccles Conference Center Auditorium
Phosphorus and nitrogen cause algal blooms that decrease water quality of lakes, rivers and coastal ecosystems. Although phosphorus control has frequently been implemented to reduce eutrophication, several lines of evidence indicate that nitrogen also needs to be controlled in some situations. Whole-lake experiments, and a correlation analysis of N, P, and chlorophyll in 1268 US lakes all indicate that nitrogen and phosphorus together produce larger algal blooms than do addition of each nutrient alone. Nitrogen fixation by cyanobacteria may alleviate nitrogen deficiencies in some cases, but ecological constraints on this process, coupled with high levels of denitrification, can lead to co-limitation by both nutrients. Although a phosphorus-only explanation for algal blooms has persisted for decades, this misinterpretation has impeded efforts to understand how nitrogen and phosphorus can both influence algal communities. Nutrient controls at watershed scales are further complicated because controlling only one nutrient in upstream areas results in export of the other damaging nutrient downstream to coastal areas. Additional research is needed to understand when and where joint controls are necessary to control eutrophication.
https://digitalcommons.usu.edu/runoff/2015/2015Posters/11