甲磺隆结合态残留物对土壤微生物的影响

Influence of Metsulfuron-methyl Bound Residues on Soil Microorganisms

研究了不同处理土壤中结合态甲磺隆残留物对土壤微生物群落的影响。结果表明 ,在供试浓度下 ,土壤中甲磺隆结合态残留物的生态效应仍不容忽视 ,其对土壤细菌、真菌具有显著的刺激作用 ,而对土壤放线菌却有强烈的抑制作用 ,抑制率高达 10 0 % ,至培养结束时 (84 d)放线菌数量还未恢复到对照水平。但微生物反应程度在不同土壤、氮素水平及培养时间上皆存在一定的差异性。土壤微生物群落 ,尤其是放线菌可作为评价甲磺隆除草剂残留污染土壤生态环境效应的敏感指标。外源氮素 (尿素 )的添加 ,既能增加土壤微生物的数量 。

Under the experimental concentration of metsulfuron-methyl bound residues, the change of microbial community structure could be caused in soil. The number of soil bacteria and fungi were increased, while soil actinomyces were inhibited by metsulfuron-methyl bound residues. The maximum inhibitory ratio of soil actinomyces reached 100 percent, and the growth of soil actinomyces did not recovery after incubatior was finished (84 d). The influence of metsulfuron-methyl bound residues on soil microorganisms was differently depended on soil types and incubation time. Soil microbial population, especially soil actinomyces, may be taken as the sensitive indicators for assessing the ecological effect of metsulfuron-methyl bound residues in soils. After nitrogen (urea) was added, the number of soil microorganisms increased, and the toxicity of metsulfuron-methyl bound residues to soil actinomyces decreased.