Study On Soil Erosion Resistance Of Representative Economic Forest In Hilly Area Of South Jiangxi Province

Southern hilly region of Jiangxi is located in the south of Jiangxi Province,which is an important part of the southern hilly mountain barrier zone in China.It plays an important role in the ecosystem services of the southern hilly mountain barrier zone and the ecological security of Poyang Lake Basin.Moreover,due to the abundant heat and rainfall,the hilly area of Southern Jiangxi provides excellent natural conditions for the planting of navel orange,tea and other economic forests.However,due to the rapid development of fruit forest in South Jiangxi in recent years,large-scale natural forest has been developed into economic fruit forest,and at the same time,it is easy to cause flood disaster due to the same period of rain and heat in South Jiangxi.These reasons have caused the problem and risk of soil and water loss in the hilly area of South Jiangxi.Therefore,it is of great significance to study the soil anti erodibility of representative economic forests in the hilly area of Southern Jiangxi.In this paper,the soil anti erodibility characteristics of navel orange,bamboo and tea plantations were analyzed by means of field investigation and laboratory experiment.The index evaluation system of soil anti erodibility of different economic forests in hilly area of South Jiangxi was established by principal component analysis and correlation analysis,and the strength of soil anti erodibility of different economic forests was explored,and the most suitable index was selected The main results are as follows:(1)After the coniferous and broad-leaved mixed forest is developed into other economic forest,or the economic forest is cut down and laid aside as wasteland,the soil bulk density and pad value will increase significantly,and the total porosity,MWD,GMD,wsa0.25 and organic matter content of soil will decrease significantly,which is not conducive to the accumulation of soil organic matter,and will lead to the fragmentation of large aggregates in the soil,The content of micro aggregate and powder + clay aggregate increased significantly.(2)After the coniferous and broad-leaved mixed forest was developed into bamboo forest and navel orange forest,or economic forest was felled and abandoned into wasteland,the soil shear strength and anti erosion index decreased.The soil anti erosion index showed as follows: tea forest(88.00%)> coniferous and broad-leaved mixed forest(85.33%)> navel orange forest(76.44%)> bamboo forest(53.78%)>wasteland(21.78%),resulting in the reduction of soil shear resistance and anti disintegration ability,The soil erosion resistance is reduced.(3)Through principal component analysis and correlation analysis,the comprehensive soil anti erodibility of each economic forest was coniferous and broadleaved mixed forest(4.71)> tea forest(4.66)> navel orange forest(4.51)> bamboo forest(4.08)> wasteland(3.85).Soil moisture content,soil organic matter,soil internal friction angle and soil anti erodibility index were significantly positively correlated with soil anti erodibility,which were the key indicators to evaluate soil anti erodibility.