Author(s)

Soni M. Pradhanang, Rajith Mukundan, Mark S. Zion, Elliot M. Schneiderman, Donald Pierson, Tammo S. Steenhuis

Department of Biological and Environmental Engineering, Cornell University, Ithaca, USA.
Institute for Sustainable Cities, Hunter College, City University of New York, New York, USA.
New York City Department of Environmental Protection, Kingston, USA.

In-stream nutrient release and retention control the timing and quantity of export at the watershed outlet by mobilization and transport of phosphorus (P) sources from land to the channel, and remobilization of transient stores of P from stream beds. We investigated the significance of stream processes in regulating P loading to the Cannonsville watershed, NY, USA. A mass balance of estimated P inputs to the stream with observed P export at the watershed outlet was used to quantify P delivery and explore the behavior of P. Stream channel transport of both dissolved and particulate P is found to be non-conservative, with dissolved P being retained during low flows and particulate P released during high flows. The results suggest that differences in the magnitude and relative importance of in-stream biogeochemical processes under different flow regimes regulate P delivery in ways that may influence ecological impacts to downstream river reaches and reservoirs.

Point Sources; Non-Point Sources; P Release and Retention; Linear Mixing; E-EMMA

Pradhanang, S. , Mukundan, R. , Zion, M. , Schneiderman, E. , Pierson, D. and Steenhuis, T. (2014) Quantifying In-Stream Processes on Phosphorus Export Using an Empirical Approach. Journal of Water Resource and Protection, 6, 120-131. doi: 10.4236/jwarp.2014.62017.