Abstract
Based on vertical distribution of the pesticides in a reservoir, a correct monitoring method of pesticide residues originated from paddy field application were investigated in this study. The spatial distribution of pesticides in thermally stratified water clearly shows that concentrations of the pesticide residues were same levels as in the inlet part of the reservoir. Therefore, the dominant residues of pesticides were present in the middle water layer. The results of the study indicate that spatial monitoring as well as periodical moni toring is essential for the accurate evaluation of the pesticide residues in the lake and reservoir water.
