A COMPARISON OF POTENTIAL CONTAMINATION FROM CONVENTIONAL AND ALTERNATIVE CROPPING SYSTEMS IN NORTHEAST KANSAS

Surface-water contamination from agricultural chemicals is a problem i n northeast Kansas. The objective of this study was to compare potenti al atrazine, nitrogen, and sediment loadings from conventional and alt ernative cropping systems in the region. Annual contamination loadings and the associated environmental risk under each system were simulate d. Results indicated that several alternative systems have lower mean annual lending levels for atrazine and sediment than the conventional system, but higher nitrogen levels. The 20-year mean contaminant loadi ngs varied widely across practices, across contaminants, and within pr actices. Low variation was associated equally with both high and low c ontaminant levels. Recently concerns regarding agrichemicals, especial ly atrazine, in northeast Kansas surface water have increased signific antly because the area is a major source of drinking water for Kansas City and nearby towns. Atrazine, a herbicide that selectively controls broadleaf weeds and certain grass weeds in corn and sorghum, is one o f the most commonly appearing chemicals. Atrazine is widely used in ag ricultural production in northeast Kansas (Diebel et al. 1993a) becaus e it economically and effectively controls competition from weeds (Reg ehr et al. 1992).