Distribution Characteristics Of Soil Physical And Chemical Properties And Microbial Community Diversity Under Erosion Environment

Soil erosion is one of the major environmental problems in the world today,and its land degradation and productivity reduction are currently the focus of soil science,environmental science and ecology.In order to solve the problem of soil erosion in the environment,this study selected three locations in the southern part of the Loess Plateau(Fuxian),the Loess Plateau water erosion wind erosion area(Shenmu)and the northeast typical black soil flood hill area(Heshan).Taking surface soil as the research object,the relationship between soil physical and chemical properties and biological properties,soil organic carbon and nitrogen mineralization and soil physical and chemical properties under different erosion intensity and vegetation restoration measures were analyzed to determine soil erosion and vegetation restoration.The soil effect of the measures;the diversity of soil microbial community structure under different erosion intensities was also analyzed to determine the factors affecting the distribution of microbial communities and their relationship with soil carbon and nitrogen content and mineralization.The main findings are as follows:(1)Vegetation restoration significantly increased soil nutrients such as carbon,nitrogen,phosphorus and potassium as well as soil moisture content.The soil nutrient content in the floodplain area of the northeast and the water erosion area in the southern part of the Loess Plateau decreased with the increase of erosion intensity.(2)Vegetation recovery significantly increased soil macroaggregates and microaggregates and their combined carbon and nitrogen contents.The microaggregates in vegetation restoration contributed the most to the increase of soil carbon and nitrogen.The carbon and nitrogen contents of soil aggregates in the erosion hills of the floodplain in the northeast and the water erosion area in the south of the Loess Plateau decreased with the increase of erosion intensity.(3)The first-order rate constant of organic carbon mineralization in the water erosion zone in the south of the Loess Plateau,the water erosion wind erosion zone in the Loess Plateau and the hilly area in the northeast is not affected by soil carbon and nitrogen content,and the accumulation of mineral carbon and potential mineralization of soil organic carbon and soil There was a positive correlation between total organic carbon and total nitrogen content,and there was a significant negative correlation between soil organic carbon mineralization rate and potential carbon mineralization ratio.There was a significant positive correlation between soil organic nitrogennitrification and organic nitrogen mineralization and soil organic carbon and total nitrogen.(4)The distribution of soil microbial communities on the erosion slopes in the southern part of the Loess Plateau and the erosion hills in the northeast of the Loess Plateau is similar.The microbial diversity index is in the water erosion area of ??the southern Loess Plateau and the slope of the floodplain in the northeast.The differences in the different erosion intensity regions are not significant and are not affected by the erosion intensity.In the erosive environment,compared with the bare slope,the soil nutrients such as carbon,nitrogen,phosphorus,potassium and mineral nitrogen in the slope on the vegetation restoration process increased significantly,and the proportion of large aggregate components in the soil increased.It indicated that vegetation restoration could improve soil fertility and improve soil structure;vegetation restoration also significantly improved soil organic nitrogen mineralization.The soil nutrient content of soil with high clay and high content is significantly higher than that of soil with high sand content.The microbial community in the water erosion area in the south of the Loess Plateau and the hilly area in the northeast of China is the same as the main bacterial group at the door level,and the microbial diversity The difference of sex index in different erosion intensity areas was not significant,indicating that soil erosion intensity had no significant effect on soil microbial community structure.