ARS | Publication request: SCALING RELATIONSHIPS FOR WATERSHEDS IN THE ATLANTIC COASTAL PLAIN OF THE SOUTHEASTERN U.S.

Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: November 28, 2000
Publication Date: November 28, 2000
Citation: BOSCH, D.D., SHERIDAN, J.M., HUBBARD, R.K., LOWRANCE, R.R., POTTER, T.L., STRICKLAND, T.C., TRUMAN, C.C., WAUCHOPE, R.D. SCALING RELATIONSHIPS FOR WATERSHEDS IN THE ATLANTIC COASTAL PLAIN OF THE SOUTHEASTERN U.S.. AMERICAN GEOPHYSICAL UNION. 81(48):F382. 2000.

Technical Abstract: Large spatial and temporal variability observed at the watershed scale make it difficult to relate watershed scale hydrologic and water quality observations to changes in landscape management. Because of this, most studies which examine cause and effect relationships between land management and hydrologic responses are done at plot and field scales. The difficulty then is relating the small scale observations to watershed scal responses. The USDA-ARS, Southeast Watershed Research Laboratory (SEWRL) in Tifton, Georgia has collected more than 30 years of hydrologic and climatic data from the 334 km2 Little River Watershed (LRW). The LRW is typical of the heavily vegetated, slow-moving stream systems in the Atlantic Coastal Plain Region of the Southeastern United States. On the LRW, approximately 30% of the precipitation received on the watershed leaves as streamflow, including surface runoff and shallow groundwater flow. Field studies indicate the surface runoff component varies from 7 to 20% of precipitatio whileshallow return flow varies from 3% to 22%. The scale of concern, field or watershed, has a large effect on the dominant flow process. At the watershed scale the processes can be separated. Similarly, the transport of eroded sediment and agrichemicals varies considerably from upland field to stream. The methods used to relate observations made at the plot and field scale to those made at the watershed scale must incorporate the geophysical processes occurring between them.