Study on Effects of Glyphosate on Soil Enzyme Activity and Respiratory Intensity of Soil

[Objective] The aim was to study the effects of glyphosate on soil environmental quality.[Method] Soil in 2-20 cm layer of vegetable field without glyphosate pollution was collected.After dried,the samples were leached with 30 mesh sieve.The samples were cultured for 7 d,and then the glyphosate was added into soil,the concn.of glyphosate in soil samples were 0.04,0.40,0.80,4.00 mg/kg resp.Soil samples were selected in different culture time to determine the activities of urease and catalase and the CO2 content from soil respiratory.[Result] After 1 d of glyphosate application,the inhibition rates of 0.04,0.40,0.80,4.00 mg/kg glyphosate on soil urease activity were 26.1%,22.4%,20.5% resp.The inhibition rate of 4.00 mg/kg glyphosate on soil catalase activity was 42.7%,other treatments all had activation effect on soil catalase activity.Glyphosate had inhibition on respiratory intensity of soil,and the higher the glyphosate concn.was the stronger its inhibition on respiratory intensity of soil was.[Conclusion] At the end of the test,the effects of glyphosate on activities of urease and catalase and respiratory intensity of soil disappeared.