AGRICULTURAL CHEMICALS IN THE ALLUVIAL AQUIFER OF A TYPICAL COUNTY OF THE ARKANSAS DELTA

摘要

Statistical method and a Geographic Information System (GIS) were used to investigate potential indicators of ground water vulnerability to agricultural chemical contamination in a representative area of the Mississippi River alluvial aquifer. A total of 47 wells were sampled for analysis of nitrate, phosphorous, potassium, and 13 pesticides commonly-used in the area.Ten soil and hydrogeologic variables and five ground water vulnerability indices were examined to explain the variations of chemical concentrations. The results showed that no individual soil or hydrogeologic variables or their linear combinations could explain more than 25/100 of the variation of the chemical concentrations.