Effects of surface cracks caused by coal mining on microorganisms and enzyme activities in rhizosphere of Salix psammophila

For contrast with those Salix psammophilas not passed through by cracksthrough measuring soil samples in 0-1010-20 and 20-40 cm soil layersand using statistical analytical methodthe distribution characteristics of soil microorganisms and soil enzyme activities in rhizosphere of Salix psammophila passed through by cracks caused by underground coal mining in Shendong mining areaBulianta coal mine were analyzed.The results show that surface cracks can reduce the number of soil bacteriaactinomyces and fungiimprove the activity of soil sucrosephosphatase and ureaseand chang the inner relations between different microorganismsdifferent soil enzymeand microorganisms and soil enzymes in rhizosphere of Salix psammophila.After more than a yearthe effects of surface cracks on fungi quantityphosphatase activity and sucrase activity in deep soil are weakenedwhile the effects of surface cracks on the number of bacteria and actinomycesurease activity and sucrase activity in surface soil are unabated.The vertical distribution characteristics of the degree declined of the number of bacteria and fungi and the degree increased of the activity of sucrase and phosphatase are changed.It can be concluded that surface crack has certain influence on the biological activityand the biological activity has certain self-repair abilitybut the complete recovery of biological activity may take a longer time in rhizosphere of Salix psammophila.