Abstract: Nutrient status and enzyme activities of acidified tailings in the Tongling copper mine area under Phragmites australis,Cynodon dactylon,and Paspalum distichum communities were studied in this paper.The pH value,electric conductivity,and contents of organic matter,total nitrogen,available phosphorus and available potassium in the tailings were determined by routine methods,and the activities of catalase,arylsulfatase,urase,acid phosphomonoesterase and dehydrogenase were determined by substratereaction method.Comparing with acidified bare tailings,the tailings under P.australis,C.dactylon,and P.distichum communities had higher pH value and lower electric conductivity,and their acidification process was slowed down.P.australis and C.dactylon communities could increase the total nitrogen,available potassium and organic matter contents of the tailings significantly (P<0.05),but the available phosphorus content of the tailings under the three natural plant communities did not have any change.The establishment of plant communities also increased the catalase,arylsulfatase and urase activities of the tailings significantly (P<0.05),but the activities of acid phosphomonoesterase and dehydrogenase did not increased significantly.Under plant communities,the tailings were meliorated,and P.australis and C.dactylon communities had better effects than P.distichum community.The activities of test enzymes except acid phosphomonoesterase had a significantly positive correlation (P<0.01) with the contents of organic matter and total nitrogen,which provided scientific evidence to use enzyme activities as the indicators of the tailings’ properties.

Key words: Species diversity, Managed ecosystem, Stabilit