吡唑草胺在土壤中的环境行为研究

Study on environmental fate of metazachlor in soil

为科学评价吡唑草胺的环境风险,参照"化学农药环境安全评价试验准则",研究了吡唑草胺在土壤中的主要环境行为——光解、挥发、吸附、移动及降解的特性。结果表明:光解、挥发不是吡唑草胺在土表降解的主要因素;吡唑草胺在土壤中具中等移动或可移动特性,难被土壤吸附;吡唑草胺在土壤中的降解受土壤类型以及环境条件(好氧、积水厌氧)的影响,其降解半衰期为4～96 d。由于吡唑草胺在粘土中移动性较强、降解半衰期较长,因此当在该种土壤上使用吡唑草胺时,可能会对地下水、地表水造成污染。

To provide a scientific basis for environmental risk assessment of metazachlor, the environmental fates of metazachlor, including photodegradation, volatilization, absorption, mobility, degradation in soil, were studied according to ＂Experimental Guideline for Environmental S＇dfety Evaluation of Chemical Pesticides＂. Results showed that photolysis and volatilization were not important fate of metazachlor on soil surface ; metazachlor was moderate to highly mo- bile in soil and did not adsorb strongly to solid matrices ; the half-life of metazachlor in soil varied depending on soil types and environmental conditions （aerobic and anaerobic in water）, and was estimated to be 4 -96 days. However, metazachlor has the potential to pollute ground and surface water due to its relatively high mobility and long half-life in clay.