Abstract: Through field trials and laboratory experiments, the laws of atrazine degradation and metabolism in soils andtheir relationship to soil characteristics are reported.The results shown, atrazine would be degraded up to 90 % in thevegetation period after its application. The metabolic pathways would be affected by the soil acidities In alkaline soil,atrazine broken down through microbial metabolization. In acidic soils, atrazine degraded mainly through chemicalhydrolysis. The degradat ion product was mainly 2-hyd roxyatrazine. The half life of atrazine in acidic soil was 63 days,much shorter than in weak acidic soil(DT₅₀ = 84 days). Whereas in the alkaline soil,the half life of atrazine was theshortest(DT₅₀=51 days).

Key words: atrazine, metabolite, soil, persitance