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

Rhizosphere was a special area around plant roots.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 100~3 000 mgPb/kg to the soil,the trend of the amount of microorgnism increased.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.