Submitted to: American Water Resources Association Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 8/31/2000
Publication Date: 10/1/2000
Citation: Williams, R.G., Lowrance, R.R., Inamdar, S.P. 2000. Simulation of nonpoint source pollution control using the riparian ecosystem management model (remm). American Water Resources Association Conference Proceedings 1000. P. 433-438.
Interpretive Summary: REMM (Riparian Ecosystem Management Model) is a computer simulation model. REMM models the wooded and grassy areas between agricultural fields and streams. The purpose of the modeling is to investigate water, sediment, nitrogen, phosphorus, and organic matter movements from the field to the stream, where it is considered nonpoint source pollution. Many state and federal water quality improvement programs are starting to use buffers to slow water movement, trap sediment and organic matter, and retain plant nutrients in their trees and grasses. The USDA-Natural Resource Conservation Service (NRCS) has developed suggested practices for determining the size and vegetation types used in designing riparian buffers. This study uses data collected at the USDA-ARS's Southeast Watershed Research Laboratory to set starting conditions for REMM and for field runoff values that would be seen in the southeastern United States under normal agricultural production. Using this data various computer simulations are made with buffer sizes and vegetation types covered in the NRCS's suggested practices. Using REMM, 14 different buffer size and vegetation types were studied to see how much nitrogen and phosphorus were retained in the buffers and how water movement changed. Also studied was how well these same buffers would work if the field was used for land application of dairy manure instead of normal agricultural production.
Technical Abstract: Many state and federal water quality programs are implementing conservation buffers for water quality improvement. The Riparian Ecosystem Management Model (REMM) has been developed as a tool to determine the effectiveness of riparian buffers in controlling nonpoint source pollutants from agricultural fields. REMM has been tested for a mature buffer system receiving typical field inputs for the Coastal Plain of the southeastern United States. This study used the data developed for testing REMM to evaluate the effect of buffer size and vegetation type on water, nitrogen, and phosphorus leaving the buffer systems. The buffer size and vegetation type selected for simulation are covered within USDA-NRCS practices. In addition, the field loadings to the buffers were adjusted upward to reflect values that had been observed at a dairy effluent irrigation site. This study provides insights into the water movement and nutrient cycling interactions that affect retention and removal of nitrogen and phosphorus by riparian buffer systems.