HR: 0800h
AN: H51B-0462    [Abstracts]
TI: Ground Water, Surface Water and Land Interactions for Soluble Reactive Phosphorus and Nitrate at a Dairy Farm in a Catskill Mountains' Valley
AU: * Flores-López, F
EM: ff35@cornell.edu
AF: Biolological & Environmental Engineering Cornell University, 206 Riley-Robb Hall, Ithaca, NY 14853, United States
AU: Easton, Z
EM: zme2@cornell.edu
AU: Steenhuis, T
EM: tss1@cornell.edu
AB: Surface waters in many areas of the Northeastern United States are characterized by high phosphorus and low nitrate concentrations. Two best management practices (BMPs), fencing cattle path and stream cattle crossing, were implemented to remove or to limit production of pollutants from non-field areas. This research examines the potential of soluble phosphorus and nitrate contributions to stream waters on a valley dairy farm in the Cannonsville basin of the New York City reservoir system. Soluble reactive phosphorus (SRP), nitrate (NO3--N), dissolved organic carbon (DOC), and dissolved oxygen (DO) concentrations were measured at regular intervals over a 3 yr period, and analyzed via a mixed model statistical procedure to determine the cause of the observed trends in N and P levels. In addition, the effectiveness of the BMPs to improve the water quality in the streams was investigated. SRP concentrations in stream water were surprisingly low with concentrations between 0.001 and 0.100 mg L-1 but with peaks related to the time prior to the implementation of the stream cattle crossing. The effectiveness of the stream cattle crossing was determined in a 30 percent decrease for SRP concentrations in stream water. The highest nitrate and SRP concentrations were observed during the summer, and were influenced by the stream bottom remove for P and denitrification for N but not by inputs from groundwater. Results of the mixed model analysis highlighted the importance of rainfall, stream cattle crossing implementation and DOC in NO3--N and SRP availability in stream flow. These results demonstrate the importance of identifying processes that describe how pollutants move in the environment, which provides useful information for targeted water quality management.
DE: 1806 Chemistry of fresh water
SC: Hydrology [H]
MN: 2007 Fall Meeting