原位土壤中乙草胺降解迁移规律研究

通过原位试验,研究了乙草胺在海伦农田黑土中残留和迁移的时间特征和微生物对乙草胺的降解作用。结果显示:乙草胺按推荐量施入土壤后,在0-10cm层次微生物降解作用非常明显,使乙草胺残留显著降低,同时由于海伦黑土有机质含量高,保水能力强,因而乙草胺不易向深层移动。但连续降水显著促进乙草胺向下层土壤迁移并有所积累,因此施药初期要尽量避开此种天气,以提高乙草胺持效性并降低其生态环境风险。

Studies on the In-situ Character of the Degradation and Transferring of Acetochlor in Soil

The character of the microbial degradation and transfer of acetochlor in soil was studied by in-situ field experiment in Hailun,Heilongjiang. The results indicated that the degradation of acetochlor in soil was rapid and significant at 0-10cm layer after acetochlor was applied at the recommended amount which was contributed to the rapid decrease of acetochlor. Meanwhile, the transfer of acetochlor was also reduced due to both the high content of soil organic matter and the water hold capacity. While continuous rainfall accelerated acetochlor transfer to deeper layers and accumulated later. For this reason, the rainfall day should be avoided shortly after acetochlor was sprayed in order to improve the availability and reduce the environmental risk of pollution.