灭线磷在稻田土壤和田水中的降解动态和残留分析

采用气相色谱法研究了10%灭线磷GR(颗粒剂,下同)中灭线磷在广东省、湖北省两地水稻田土壤和田水中的残留降解动态和最终残留量.研究结果表明灭线磷在土壤和田水中的添加回收率分别为82.85%～93.70%和85.03%～98.17%.灭线磷在稻田土壤和田水中降解动态符合一级动力学指数模型,在广东省和湖北省稻田土壤中的半衰期分别为9.73 d、10.70 d,田水中的半衰期分别为0.83 d、0.85 d.10%灭线磷GR以(1800 g(a.i.)·m~(-2)和2700 g(a.i .)·hm~(-2)两个剂量施药后,灭线磷在广东省土壤中的最终残留质量分数为0.002 3～0.0034mg·kg~(-1);2700 g(a.i.)·hm~(-2)施药后,灭线磷在湖北省土壤中的最终残留质量分数为0.001 7 mg·kg~(-1),1800 g(a.i.)·hm~(-2)施药后,在土壤中未检测出灭线磷.

Degradation dynamics and residues analysis of ethoprophos in paddy soil and paddy water

Degradation dynamics and terminal residue of ethoprophos of 10% ethoprophos GR in paddy soil and paddy water of Guangdong province and Hubei province in 2006 were investigated by gas chromatography. The results showed that the recoveries of ethoprophos from paddy soil and paddy water was 82.85%～93.70% and 85.03%～98.17%, respectively. Degradation dynamic equations of ethoprophos in paddy soil and paddy water was based on first-order reaction dynamic equations. The half-life of degradation of ethoprophos was 9.73 d and 10.70 d in paddy soil of Guangdong province and Hubei province, respectively. The half-life of degradation of ethoprophos was 0.83 d and 0.85 d in paddy water of Guangdong province and Hubei province, respectively. The final residual of ethoprophos in paddy soil of Guangdong province was 0.002 3～0.003 4mg·kg~(-1) when using dosages of 10% ethoprophos GR were 1 800 g·(a.i .)·hm~(-2) and 2 700 g·(a.i .)·hm~(-2) in Guangdong province. The final residual of ethoprophos in paddy soil of Hubei province was 0.001 7 g·kg~(-1) when using dosage of 10% ethoprophos GR was 2 700g·(a.i .)·hm~(-2), while ethoprophos in paddy soil of Hubei province was not detected when using dosage of 10% ethoprophos GR was 1 800 g·(a.i .)·hm~(-2).