HR: 0800h
AN: B51A-0188    [Abstracts]
TI: Prediction of Nitrogen Leaching from Freshly Fallen Leaves: Application of Riparian Ecosystem Management Model (REMM)
AU: * Bhat, S
EM: shirish.bhat@gmail.com
AF: University of Florida, Department of Civil and Coastal Engineering, Gainesville, FL 32611 United States
AU: Kirk, H
EM: khatf@ce.ufl.edu
AF: University of Florida, Department of Civil and Coastal Engineering, Gainesville, FL 32611 United States
AU: Jacobs, J
EM: jennifer.jacobs@unh.edu
AF: University of New Hampshire, Department of Civil Engineering, Durham, NH 03824 United States
AU: Lowrance, R
EM: lorenz@tifton.usda.gov
AF: USDA-ARS, Southeast Watershed Research Laboratory, Tifton, GA 31793 United States
AU: Williams, R
EM: randy@tifton.cpes.peachnet.edu
AF: USDA-ARS, Southeast Watershed Research Laboratory, Tifton, GA 31793 United States
AB: Litterfall is usually the most important flux for the return of most nutrients to soils in forested ecosystems. Leaf litter comprises approximately 80% of the total litterfall. After leaves have fallen, the first precipitation events result in nitrogen leaching and a corresponding increase in nitrogen levels in the soil and stream water. This immediate release is of particular interest in low nutrient systems. In these systems, nutrient release prior to litter decomposition may be a significant source of stream water chemistry variation. To explore the nitrogen dynamics in the riparian area during litterfall, the Riparian Ecosystem Management Model developed by USDA-ARS was used to model a second-order watershed in Fort Benning, Georgia. For calibrated simulation results for a four-year period, the modeled streamflow's Nash-Sutcliffe efficiency was 80%. The model effectively captured the trends of litter mass production in the riparian area and subsequent high concentrations during those periods. Six storm events between October 2002 and May 2003 were analyzed to evaluate the effects of precipitation in leaching the nitrogen from freshly fallen leaves. The simulated TKN mass during the events closely matched the observed values.
DE: 0483 Riparian systems (0744, 1856)
DE: 0496 Water quality
SC: Biogeosciences [B]
MN: Fall Meeting 2005