Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Hangzhou 310058, China; School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, China.
Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Hangzhou 310058, China.
Environ Pollut. 2018 Feb;233:745-754. doi: 10.1016/j.envpol.2017.10.114. Epub 2017 Nov 8.
The incorporation of various types of crop straw to agricultural soils has long been practiced to improve soil fertility. However, the effects of crop straw on the fate of organo-chlorine pesticides in flooded paddy soils are not well understood. The dechlorination of pentachlorophenol (PCP) in four vertical profiles (0-10, 10-20, 20-30, 30-50 mm depth) of two flooded paddy soils, a Plinthudult (Soil 1) and a Tropudult (Soil 2) was investigated following the application of four crop straws (rice, wheat, rape and Chinese milk vetch) to them. In all treatments, PCP dechlorination decreased with increasing soil depth. In the crop straw treatments, PCP was almost completely dechlorinated within 60 days, and rapidly transformed to 2,3,4,5-tetrachlorophenol, and further to 3,4,5-trichlorophenol. Further dechlorination of 3,4,5-trichlorophenol also occurred in all treatments except for the rape straw. It is possible that the NH and NO derived from the straw are responsible for the inhibition of the 3,4,5-trichlorophenol dechlorination. The reduction of Fe (III) and SO increased following application of the crop straws. The RDA analysis indicated that the Fe (III) reducing bacteria might be involved in the ortho-dechlorination, while SO reducing bacteria were involved in para- and meta-dechlorination of PCP. The complete detoxification of PCP depended upon both the crop straw type and soil properties.
将各种类型的作物秸秆掺入农业土壤中以提高土壤肥力的做法由来已久。然而,作物秸秆对淹水稻田土壤中有机氯农药命运的影响尚不清楚。在向两种淹水稻田土壤(Plinthudult(土壤 1)和 Tropudult(土壤 2))中施加四种作物秸秆(水稻、小麦、油菜和紫云英)后,研究了五氯苯酚(PCP)在四个垂直剖面(0-10、10-20、20-30 和 30-50mm 深度)中的脱氯情况。在所有处理中,PCP 的脱氯作用随土壤深度的增加而降低。在秸秆处理中,PCP 在 60 天内几乎完全脱氯,并迅速转化为 2,3,4,5-四氯苯酚,进一步转化为 3,4,5-三氯苯酚。除油菜秸秆外,所有处理中 3,4,5-三氯苯酚也进一步脱氯。可能是秸秆中的 NH 和 NO 导致 3,4,5-三氯苯酚脱氯受到抑制。施加作物秸秆后,Fe(III)和 SO 的还原增加。RDA 分析表明,Fe(III)还原菌可能参与邻位脱氯,而 SO 还原菌参与 PCP 的对位和间位脱氯。PCP 的完全解毒既取决于秸秆类型又取决于土壤性质。