论文部分内容阅读
研究了氟乐灵、甲基对硫磷和三唑酮在４种土壤中的光解速率以及土壤湿度、构成、有机质和ｐＨ对光解的影响。结果指出土壤粘粒含量和土壤湿度是影响农药在土壤中光解的重要因素。农药先解速率随粘粒含量减少而加快，相关非常显著。而土壤有机质含量和ｐＨ对光解影响均不明显。土壤湿度对不同农药光解影响的差异很大，氟乐灵在湿润和干燥土壤中的光解速率相差达１１．２～２１．２倍，而甲基对硫磷的差异仅１．４～２．０倍；不同种类土壤的湿度对农药光解的影响也有明显差异。说明土壤中水份的作用和农药先解反应类型、自由基形成和水分改变土壤吸收光谱有关。
The photodegradation rates of trifluralin, methyl parathion and triadimefon in four soils and the effects of soil moisture, composition, organic matter and pH on photolysis were studied. The results indicated that soil clay content and soil moisture are the important factors affecting the photodegradation of pesticides in soil. Pesticide first solution rate with the reduction of clay content to speed up, the correlation is very significant. Soil organic matter content and pH had no obvious effect on photolysis. The effect of soil moisture on the photochemical degradation of different pesticides was quite different. The difference of photodegradation rates of trifluralin between moist and dry soils was 11.2-21.2 times, but the difference of methyl parathion was only 1.4 ~ 2.0 times; different types of soil moisture on the photochemical degradation of pesticides also have significant differences. Explain the role of soil moisture and pesticide first reaction type, the formation of free radicals and water changes in soil absorption spectra.