Study On Plant And Microbial Diversity In Xiangtan Manganese Mine Restoration Area

Mining has caused serious pollution to the atmosphere,water resources and soil in the mining area,and the ecological system has also been seriously damaged.If it is not repaired,it will cause serious problems such as resource depletion,soil erosion and so on,and finally affect the production and life of people around the mining area.It is difficult to achieve the restoration effect in a short period of time by natural succession of mine wasteland.Therefore,it is necessary to use biology and engineering technology to carry out restoration and vegetation reconstruction,so as to help the mine plant community accelerate the realization of natural succession and finally meet the requirements of original ecosystem biodiversity.In the process of ecosystem restoration,plants and soil microorganisms play a very important role,the changes of plant and soil microbial diversity,community structure characteristics and the relationship with environmental factors need to be studied in the process of mine wasteland restoration.In this study,we selected the original remnant forest of Pinus massoniana,and five types of vegetation in the artificial restoration area:the shrub of Broussonetia papyrifera,the forest of Koelreuteria paniculata,the forest of Osmanthus fragrans,Setaria viridis and Cynodon dactylon,as our study area,to study the diversity of aboveground plants and underground microorganisms and their relationship with environmental factors.The main results are as follows:(1)Through field investigation of plants in the manganese mining area,it was found that there were a total of 79 species of plants,belonging to 40 families and 72 genera.The vegetation types are mainly herbaceous plants,among which the plants of Gramineae,Compositae and Rosaceae are the dominant species in the mining area and grow well.The results of plant diversity analysis showed that the diversity index of Pinus massoniana forest was higher than that of others communities,and the diversity of Koelreticulata paniculata forest in the artificial restoration area was higher than that of others communities.The diversity index of tree,shrub and herb layer in each community showed the regularity of herb layer>shrub layer>tree layer.(2)By analyzing the correlation between plant community diversity and soil factors,it was found that the plant diversity index was positively correlated with soil C,N,P.pH and the heavy metal Mn content was negatively correlated with Simpson index.(3)The bacteria in soil microorganisms were sequenced,and the results were analyzed at the taxonomic level,which were divided into 280 phyla,756 classes,891 orders,1703 families and 2293 genera.The analysis of the dominant bacterial community showed that Proteobacteria was the most dominant bacterial phylum in the soil,and the most abundant bacteria in Class was Others in the soil samples.The results of microbial diversity analysis showed that the diversity indexes of rhizosphere soil of Broussonetia papyrifera and Koelreuteria paniculata were higher than the control samples.(4)The correlation between environmental factors and soil microorganisms was analyzed.It was found that soil C,N,P,pH and heavy metal Mn contents were the dominant factors affecting soil bacterial community diversity.The study on the changes of vegetation and soil microbial diversity in mining areas by artificial reclamation measures is conducive to monitoring the effect of ecological restoration in mining areas.The study on plant and soil microbial diversity is also of great significance for the realization of ecological system reconstruction and land reuse in mining areas.