4种农药对土壤微生物的影响Ⅱ:氮素矿质化的变化

研究农药，氯氰菊酯、高效氯氰菊酯、多菌灵和丁硫克百威对山西省两种土壤氮素矿质化（ 氨化作用和硝化作用） 的影响．结果表明，添加低浓度（ ｗ ＝ １００ ｍｇ／ｋｇ） 的４ 种农药，对土壤氮素矿质化无显著影响． 高浓度（ ｗ ＝ １０００ ｍｇ／ｋｇ） 的菊酯类农药会抑制土壤中硝化细菌的活动，使土壤中氨的含量明显积累；添加高浓度多菌灵的土壤样品出现硝态氮积累的现象，这可能与其对微生物生长影响有关；添加高浓度丁硫克百威在一种土壤样品中使氨的含量有明显积累，但在另一种土壤样品中与对照基本相同．可见，农药对土壤氮素矿质化及微生物活性的影响，因农药品种的不同和浓度的不同而异，不同的土壤因微生物活性的差异而对农药污染的反应也不同

EFFECT OF 4 PESTICIDES ON SOIL MICROORGANISMS(II): CHANGING IN N MINERALIZATION

The effects of 4 pesticides, cypermethrin, alphacypermethrin, carbendazim, and carbosulfan, on soil N mineralization in 2 kinds of loamy clay soils in Shanxi Province were studied under laboratory conditions. The results indicated that the N mineralization of the soils fortified with 4 pesticides at lower concentration (100 mg/kg) was not affected significantly. At highly fortified concentration(1000 mg/kg), the N mineralization of the tested soils was disturbed in different ways. Cypermenthrin and alphacypermethrin could inhibit the nitrification process, which lead to ammonium accumulation in both soils. In the both soils fortified with carbendazim, accumulation of nitrate occurred. By carbosulfan, the accumulation of ammonium only occurred in 1 kind of soils. Thus, based on the varieties and concentration of fortified pesticides, the effects of pesticide on soil N mineralization and microbial activities were different. Soils with variable microbial diversity also shown functional differences to pesticide contamination.