二氯喹啉酸在不同土壤中的降解规律及其影响因子

Degradation Dynamics of Quinclorac and its Influencing Factors in Four Soils

采用室内模拟方法研究了二氯喹啉酸在山东、湖南、四川、云南4个烟叶主产区不同土壤中的降解动态，并探讨了土壤pH、土壤含水量、温度对其降解的影响。结果表明，二氯喹啉酸在4种土壤中的降解半衰期分别为26．8、23．9、35．6、32．4d，在云南红壤中降解最慢。在酸性土壤中，二氯喹啉酸降解慢，半衰期长；土壤相对含水量由20％增至80％，二氯喹啉酸降解半衰期由32．1d缩短至16．8d。随着环境温度升高（15～35℃），二氯喹啉酸降解的速度加快（半衰期由43．3d缩短至21．1d）。半衰期与土壤pH的回归方程为y=-3．575x＋48．425，R2=0．9929；半衰期与土壤湿度的回归方程为y=．0．2329x＋34．1，R2=0．8038；半衰期与温度的回归方程为y=．1．11x＋57．983，R2=0．9139。

The degradation dynamics of quinclorac in four kinds of soils （Shandong, Hunan, Sichuan and Yunnan） were studied in laboratory, and the effect of soil pH, moisture, and temperature on degradation was investigated. The results showed that the half-time of quinclorac in the soils was 26.8, 23.9, 35.6, and 32.4 days, and the slowest degradation was in Ytmnan soil. The degradation rate of quinclorac in acid soil was slow and the half-time was long. The half-time of quinclorac decreased with increase of soil moisture and environment temperature. The regression equation of half-life with soil pH, moisture, temperature are y=-3.575x＋48.425, R2=0.9929; y=-0.2329x＋34.1, R2=0.8038; y=- 1.1 1x＋57.983, R2=0.9139 respectively.