Characteristics And Collaborative Evolution Of Plant-Soil-Microorganism During Vegetation Restoration In Typical Watershed Of Northern Shanxi Province

With the increasingly prominent ecological environment problems,the restoration and reconstruction of fragile habitat vegetation has become one of the current research hotspots.The vegetation in typical watershed of Northern Shanxi Provincewas selected as the research object.In order to explore the dynamic changes of plant traits,soil nutrients,microbial community and their collaborative evolution during the restoration of abandoned farmland to grassland and locust in the Loess Plateau.(1)The plant traits diversity of grassland and Robinia pseudoacacia showed different growth trends with the increases of the recovery periods.In detail,grassland plant traits in coverage,richness,diversity and evenness were increased significantly from 20 to 40 years by 47.13%,41.20%,13.40% and 10.34%,respectively.Robinia pseudoacacia plant traits in coverage,richness,diversity and evenness were increased from 17 to 42 years by 81.90%,85.68%,28.16% and 22.73%,respectively,of which the coverage showed a significant increase.(2)The soil organic carbon,nitrogen and soil moisture of grassland and Robinia pseudoacacia increased significantly with the increases of the recovery periods.Soil phosphorus showed a significant increase in grassland,and increased in the Robinia pseudoacacia,but no significantly.Soil p H and bulk density fluctuated during the vegetation restoration process,and there was no obvious succession trend.(3)Vegetation restoration inevitably leads to changes in microbial communities,with the increases of the recovery periods,the bacterial alpha diversity increased significantly,while fungal alpha diversity did not show a significant increase trend,but its growth rate in each restoration stage was higher than bacterial alpha diversity.There were obvious separation and aggregation effects in each restoration stage of microbial beta diversity with the vegetation restoration.For the microbial community compositions,bacterial community transitioned from Actinobacteria-dominant with poor nutrition to Proteobacteria-dominant communities with rich nutrition and Ascomycota has an advantage in the composition of fungal community.Microbial biomass carbon,nitrogen and soil extracellular enzymes of grassland and Robinia pseudoacacia increased significantly with the increases of the recovery periods.(4)The response of grassland and Robinia pseudoacacia to plant-soil-microbial was different during the vegetation restoration process.The grassland showed that the environmental factors except soil p H and bulk density were significantly correlated with microbial communities to varying degrees.Robinia pseudoacacia showed that the environmental factors except soil phosphorus and p H were significantly correlated with the microbial communities.Indicated that although plant traits and soil nutrients response to microbial communities,the response degree of plant traits to microbial communities is stronger than that of soil nutrients.