Effects Of Different Ecological Restoration Measures On The Degraded Ecosystem In Changting County

This paper studies the ecological restoration process of degraded land from the perspective of "soil-plant-microorganism".By the methods of investigation for plant communication and soil with the combination of experimental determination and mathematical statistics,This study plans to tookake different control measures in Changting soil erosion area(measure 1: artificially planted trees,shrubs,herbs;2:artificial fertilization;3: Fertilize after planting trees,shrubs and herbs artificially;4:fertilize before planting trees,shrubs,and herbs artificially)plant-soil system as the research object,and taking took the well-preserved Feng-Shui forests and severely degraded bare ground as contrastthe reference,through plant surveys in the wild and sample collection,determination,and mathematical statistics to analyze the species composition,structure and diversity characteristics of plant communities,soil physical and chemical properties and soil microbial community characteristics,and analyze the correlation between them and explore the key factors affecting the process of ecological restoration.From the perspective of "soil-plant-microbe",we promote the benign restoration that follows the laws of nature under human intervention.The research results provide theoretical and practical basis for vegetation restoration of subtropical evergreen broad-leaved forests and ecological restoration.This study will provide a basis for ecological restoration practice and evaluation of red soil erosion areas in southern China.The main findings are as follows.results show:The characteristics of vegetation community restoration under different management measures are as follows: the plant species has increased significantly,but there is still a gap compared with Feng-Shui forests,among which the artificially planted trees,shrubs,herbs management has the most abundant plant species.The dominant families of plants in the study area mainly include Gramineae,Rubiaceae,and Aquifoliaceae.The distribution of dominant families in the four control measures is similar.Pinus massoniana Lamb and Dicranopteris pedata occupies an absolute dominant position in the arbor layer and the herb layer,and the dominant species in the shrub layer include Rhaphiolepis indica and Syzygium grijsii.In terms of community diversity and stability characteristics,Measure 2 significantly improved species diversity and richness in the arbor layer and herb layer,while the species diversity in the shrub layer was better in Measure 1.After vegetation restoration,the stability of the community has been significantly improved.Measure 3 has the best effect on improving the stability of the community.There was no significant correlation between community stability and diversity.In addition,with the increase of recovery years,the growth condition of the tree layer tends to be good,and the growth status of the shrub layer and the herb layer is different from that of the tree layer.It shows that trees,shrubs and grass occupy different ecological niches in the community.In order to avoid the degradation of plant communities,it is recommended to strengthen management after treatment.(2)The soil nutrient content of Feng-shui forest is much higher than that of bare ground.After different ecological restoration measures,the soil nutrient content has been improved to different degrees.The soil total nitrogen content plot managed by measure 2is higher,measures for artificially planted trees,shrubs,herbs have a better effect on improving soil organic matter.The content of potassium and phosphorus plot managed by measure 4 is higher.The combination of artificially planted trees,shrubs,herbs and artificial fertilization improvement measures combined with governance plots had higher soil enzyme activities.The soil microbial biomass carbon content of Feng-shui forest is much higher than that of other sample plots.The microbial biomass nitrogen is the highest plot managed by measure 2,and the microbial biomass nitrogen has a trend of increasing with the increase of governance time,but the performance is not significant.Ascomycota,Basidiomycota,Rozellomycota and Mucoromycota are the dominant phyla in soil fungal communities;Proteobacteria,Chloroflexi,Acidobacteriota and Actinobacteriota are the dominant bacteria in soil bacterial community.Vegetation restoration greatly improved soil fungal and bacterial community richness and diversity.There were significant differences in soil microbial community characteristics and αdiversity under different governance measures.The bacterial community composition of plot managed by measure 2 is close to that of Feng-shui forest.The fungal diversity and richness in soil were greatly improved by the governance of Measure 2,but there was no significant difference in soil bacterial α diversity between different governance measures.(3)Compared with bacterial communities,the diversity index of fungal communities is more closely related to plant communities.Plant and microbial diversity are co-evolutionary processes,and fungi have a greater impact on plants.The soil environmental factors that significantly affect the composition of soil fungi and bacterial communities in the treatment plots of measures 1,2,3 and 4 are soil water content and total nitrogen of soil,total potassium and total nitrogen of soil,soil bulk density and total potassium of soil,soil surcrase and soil bulk density.In general,soil organic matter,nitrogen,phosphorus and other nutrients,soil urease and acid phosphatase in measures 1,2 and 3 were positively correlated with plant community growth indicators and Margalef index.The nitrogen content and soil microbial biomass nitrogen of the control plots in Measure 4 showed the opposite trend.After treatment with different measures,the recovery effect of measure 4 was the best,followed by measure 2.