Track: Agriculture
GIS-Based Model of Salt Loading to the Groundwater for Irrigated, Agricultural Soil
Dennis L. CorwinMarcia L. K. Carrillo Ph.D. , P. J. Vaughan Ph.D., J.D.Rhodes Ph.D., D. G. Cone
Nonpoint source (NPS) pollution of soil and groundwater resources is a global concern usually associated with agricultural activities. The modeling of NPS pollutants in the vadose zone is well suited to the integration of a 1-D, deterministic model of solute transport with a GIS because of the spatial complexity and heterogeneity of soils. The transport model TETrans has been "loosely" coupled to ArcInfo for a 2,396 hectare site within the Broadview Water District in the San Joaquin Valley of central California. Visualizations displaying the simulated temporal and spatial changes in the distribution of soil salinity in the root zone and in the loading of salts to the drainage waters are presented for the period of 1991-1996 and compared to measured data. Display maps show distributions of the soil salinity to a depth of 1.2m, irrigation efficiencies, salt loading, and drainage amounts. These maps provide a visual tool for assessing the potential impact of salinity upon soil and groundwater, thus providing information to make management decisions for the minimization of environmental impacts without compromising future agricultural productivity.
Dennis L. Corwin
USSL-ARS-USDA
450 W. Big Springs Rd
Riverside, CA 92507
USA
Telephone: 909-369-4819
Fax:
E-mail: dcorwin@ussl.ars.usda.gov