ABSTRACT
The connec t ion between s o i l and wate r resources i s so i n t i m a t e t h a t any change i n one u s u a l l y a f f e c t s t h e o ther . It was assumed f o r many years t h a t s o i l c o n s e r v a t i o n p r a c t i c e s n o t o n l y p r o t e c t e d t h e s o i l b u t enhanced water q u a l i t y as w e l l . T h i s assumption was f i r s t s e r i o u s l y ques t ioned i n t h e e a r l y 1970s as e n v i r o n m e n t a l i s t s began t o l o o k f o r "best management p r a c t i c e s " (BMPs) f o r c o n t r o l o f a g r i c u l t u r a l nonpo in t source p o l l u t i o n (NPS). The genera l n o t i o n t h a t s o i l and wate r conserva t ion p r a c t i c e s (SWCPs) were good f o r wa te r q u a l i t y was n e i t h e r s p e c i f i c no r s u b s t a n t i a t e d enough f o r b l a n k e t acceptance o f SWCPs as BMPs, thus a number o f ques t ions have been ra ised . Which s o i l c o n s e r v a t i o n p r a c t i c e s a r e cand ida te BMPs f o r which water p o l l u t a n t s ? How s p e c i f i c a l l y do t h e v a r i o u s SWCPs a f f e c t t h e f a t e , and p a r t i c u l a r l y t h e t r a n s p o r t o f d i f f e r e n t p o t e n t i a l wa te r contaminants? M i g h t n o t some SWCPs r e s u l t i n even g r e a t e r use o f chemicals t h a t a r e p o t e n t i a l wa te r q u a l i t y contaminants? I n general, we found t h a t when a p r a c t i c e i s a p p l i e d w i t h a s p e c i f i c o b j e c t i v e i n mind, (e.g., conserva t ion t i l l a g e f o r s o i l e r o s i o n c o n t r o l o r reduced f e r t i l i z e r use t o p r e v e n t groundwater p o l l u t i o n ) changes occur which a f f e c t t h e t o t a l system - i n c l u d i n g phys ica l , economic and even s o c i a l components - i n complex ways. As an o l d axiom s ta tes , "There a r e many s imp le answers t o complex quest ions, b u t most o f them a r e wrong."
