PREDICTING RUNOFF-INDUCED PESTICIDE INPUT IN AGRICULTURAL SUB-CATCHMENT SURFACE WATERS : LINKING CATCHMENT VARIABLES AND CONTAMINATION

Predictive models of the relative runoff-induced insecticide loss from sub-catchements of the Laurens River (South Africa) - Use of a GIS - Lack of buffer strips, presence of erosion rills and high slopes are the main variables responsible for the high contamination of tributaries water.