Assessment of water contamination by agricultural practices

This study assesses the impact of agricultural practices on water contamination in the Triffa plain (eastern Morocco). Agricultural intensification, massive irrigation and excessive use of fertilizers and pesticides have led to a significant deterioration in groundwater and surface water quality. Physico-chemical analyses show nitrate concentrations ranging from 2.32 to 153 mg/L, exceeding the WHO standard of 50 mg/L in 73% of wells. The water also shows increased salinity, ranging from classes C3S1 to C5S3, reflecting a growing sodicity harmful to sensitive crops. Bacteriological analyses reveal almost widespread contamination by coliforms and fecal streptococci. Despite a marked chemical evolution, the water facies remains predominantly sodium chloride and calcium-magnesium chloride-sulfate. This work underlines the need for rational management of agricultural inputs to preserve the quality of the region’s water resources.