Soil microorganism and rhizospheric effect in early stage of reclamation in core-mining subsidence area

Research on soil microorganisms and rhizospheric effect could provide theoretical bases for soil quality assessment and ecological remediation in early stage of reclaimed soil in core-mining subsidence area. In this study, rhizospheric microorganisms and non-rhizospheric microorganisms after 1 year and 3 years of reclamation of core-mining subsidence in plain agriculture area were studied. The results showed that quantity of rhizospheric microorganisms and non -rhizospheric microorganisms after 1 year and 3 years of reclaimed soil was less than the control. Therefore, the percentage of bacteria, fungi and actinomyces to the control were 20.3%~66.5%,2.8%~56.3% and 1.1%~45.1%%, respectively. In addition to actinomyces, the increase of non-rhizospheric bacteria and fungi was not significant, while the number of rhizospheric bacteria, fungi and actinomyces increased significantly with the extension of reclamation time.Therefore, change trend with reclamation years was different between rhizospheric microorganisms and non-rhizospheric microorganisms.The above induced positive rhizospheric effect, with R/S values of total microorganisms being 1.7 and 3.3 after 1 year and 3 years of reclamation, respectively. The study indicated that scientific planting was beneficial for improvement of soil quality in early stage of reclamation in core-mining subsidence area.