植物根际微生物和酶活性对铅污染的响应

Effect of the Rhizosphere on the Microorganism and the Enzyme Activity in Polluted Soil with Lead

通过根际袋法土培试验研究了铅污染下不同植物根际微生物数量和酶活性变化。结果表明,随着土壤中添加Pb浓度升高,根际土壤微生物数量总的趋势增加,其所构成的三大类菌数的趋势也因植物根系环境的不同而有所区别:细菌数量增加,黑麦草和早熟禾根际土壤放线菌数量降低,翦股颖根际土壤放线菌数量呈现波动起伏;真菌数量均增加。4种植物根际土壤中过氧化氢酶活性、淀粉酶活性和中性磷酸酶活性与土壤铅含量都表现出负相关性,与淀粉酶活性负相关达到极显著,铅对黑麦草和狗牙根根际土壤脲酶活性表现出低浓度下激活高浓度下抑制,早熟禾和翦股颖根际土壤脲酶活性与土壤铅含量表现出正相关。

In order to investigate the influence of plant roots and rhizosphere microorganisms on bioremediation of soils contaminated with lead,the effect of rhizosphere on microbial numbers and activities of enzyme in rhizosphere soil were studied with rhizobag technique.The results showed that add Pb to the soil,the trend of the amount of microorganism increased.With the quantity of bacterium and fungi increased,the quantity of actinomyces reduced.In the rhizosphere of four plants,the activities of catalase,neutral phosphatase,amylase and the content of lead in soil expressed negative correlation,and the negative correlation between the activity of amylase and the content of lead in soil was remarkable.In the rhizosphere of Lolium perenne and Cynodon dactylon,the activity of urease was activated at low density of lead and descended at high density,but in the rhizosphere of Agrostis stolonifera and Poa annua,there was a positive correlation between the activity of urease and the content of lead in soil.