AGRICULTURAL WATER DEMANDS.

Abstract

Water quality is becoming an increasingly important factor in determining the levels of agricultural water use. Salinity is well recognized as an issue, and many irrigation areas have been abandoned through excessive soil salinization. Sediment, fertilizers, and pesticides in irrigation runoff are also of concern. Although livestock water demands are small compared with those for crops, the resulting wastewater can be highly polluted, especially from feedlots and piggeries. The focus of this discussion is first a brief review of unit processes; then, water demands of individual and regional agricultural activities are considered, using as an example a linear programming (LP) model dealing with a simplified agricultural system consisting of one type of crop and one type of animal. Finally, a case study of the Silistra region in Bulgaria is described, which deals with the modeling and forecasting of agricultural water demands in a large agroindustrial complex. Refs.