Abstracts

Results of Regional SPARROW Models for Selected Watershed in Mississippi

Author(s): Rebich, R.

SPARROW (SPAtially Referenced Regressions On Watershed attributes) models were developed by the U.S. Geological Survey to estimate nutrient inputs (total nitrogen and total phosphorus) to the northwestern part of the Gulf of Mexico from streams in the South-Central United States. These models included drainages in Mississippi: the Yazoo River Basin, the Big Black River Basin, and the South Independent Streams. The models were standardized to reflect nutrient sources and stream conditions during 2002.

Model results indicated that total nitrogen yields in the Yazoo River Basin generally were higher in the lower part of the Basin (an area locally referred to as the Delta) than in the upper part. Although total phosphorus yields generally were higher in the Delta than in the upper part of the Yazoo River Basin as well, yields also were high along the bluff hill area of the Basin prior to entry into the Delta area. The primary source of nitrogen and phosphorus in the Yazoo River Basin was fertilizer. Model results indicated that total nitrogen and total phosphorus yields in the Big Black River Basin were highest in the lower part of the Basin. Wet deposition of total inorganic nitrogen was the largest nitrogen source in the Big Black River Basin; for phosphorus, however, there were no dominant sources. Nitrogen yields generally were highest for areas adjacent to the Mississippi River levee and southern State boundary for the South Independent Streams Basin, whereas phosphorus yields generally were highest for areas adjacent to the Mississippi River levee. The primary source of nitrogen in the South Independent Streams Basin was wet deposition of total inorganic nitrogen; there were no dominant sources of phosphorus.

The SPARROW Decision Support System (DSS) is an online interactive tool created for these and other SPARROW models so that water managers, researchers, and the general public can have access to results for a variety of uses. Users can map loads, yields, concentrations, and sources by stream reach and catchment; track transport to downstream receiving waters, such as estuaries and reservoirs; evaluate management scenarios such as source reductions; and overlay other sources of information such as land use, states, counties, and hydrologic units. The SPARROW DSS is located at: http://cida.usgs.gov/sparrow/index.jsp .
Download the presentation

Go back

Contact

Technical Sessions

1 Best Management Practices #1
2 Delta Water Assessment
3 Flood Assessment & Mgmt.
4 Wetlands
5 Watershed Mgmt. #1
6 Non-Point Source Assessment
7 Modeling
8 Water Quality
9 Best Mgt. Practices #2
10 Delta Water Conservation
11 Sedimentation
12 Storm Water
13 Watershed Mgt. #2
14 Public Water Systems
15 Surface Water Assessment & Evaluation

Click here to view the entire agenda