ARS | Publication request: Dissolved P in streams in dry years and wet years

Submitted to: Georgia Water Resources Conference
Publication Type: Proceedings
Publication Acceptance Date: March 28, 2011
Publication Date: April 11, 2011
Citation: Franklin, D.H., Steiner, J.L., Starks, P.J., Moriasi, D.N., Duke, S.E. 2011. Dissolved P in streams in dry years and wet years. Proceedings of the 2011 Georgia Water Resources Conference, April 11-13, 2011, University of Georgia, Athens, Georgia. CDROM.

Interpretive Summary: Dissolved phosphorus (P) has often been identified as the nutrient of concern in lakes, reservoirs, and streams especially where there is evidence of eutrophication. We analyzed the influence of landscape variables and season on the variability of dissolved P [soluble reactive P (SRP)] stream concentrations during times with drought and during times with a series of severe storms (2005 through 2009) in the Fort Cobb Reservoir watershed located in southwestern OK. The streams were sampled every two weeks (212 sampling dates) for SRP. Landscape, stream, and climate were compiled for each watershed basin, within each tributary, and from climate and precipitation data, respectively, and were related to SRP concentrations for spatial dependence or no spatial dependence. After a series of extreme rainfall events (drought to heavy rainfall) the proportion of spatial dependence of stream SRP increased noticeably as did the corresponding mean stream concentration of SRP.

Technical Abstract: Dissolved phosphorus (P) has often been identified as the nutrient of concern in lakes, reservoirs, and streams especially where there is evidence of eutrophication. We analyzed contiguous-spatial and temporal variability of dissolved P [soluble reactive P (SRP)] stream concentrations during times with drought and during times with a series of severe storms (2005 through 2009) in the Fort Cobb Reservoir watershed located in southwestern OK. The streams were sampled every two weeks (212 sampling dates) for SRP. Horizontal, longitudinal, and vertical biogeophysical metrics were compiled for each contributing area, within each stream reach, and from climate and precipitation data, respectively, and were related to SRP concentrations for spatially autocorrelated data and not spatially autocorrelated data. After a series of extreme rainfall events (drought to heavy rainfall) the proportion of spatial autocorrelation of stream SRP increased significantly (p < 0.05) as did the corresponding mean stream concentration of SRP.