A modeling approach to evaluate the impact of BMPs for minimizing the phosphorus transport under sprinkler irrigation system

Abstract

The SWAT (Soil and Water Assessment Tool) has been used to evaluate the impact of several best management practices (BMPs) on water yield (WYLD) and total phosphorus (TP) at the outlet of the Del Reguero stream watershed (Spain). In total, 6 individual scenarios and 14 combinations of various management practices including tillage (conservation and no-tillage), fertilizer (incorporated, recommended, and zero), and irrigation (adjusted to crop needs) were been tested. Results indicate that the best individual BMPs (adjusted irrigation water use BMP) reduced WYLD to 31.4% and TP loads to 12.8%, in comparison of the initial conditions. When individual BMPs were combined, the reductions of losses were increased. The BMPs combination between optimum irrigation application, conservation tillage and reduced P fertilizer dose was the best analyzed one with a TP loads reduction about 22.6%.