Evaluation Of Soil Quality And Comprehensive Benefits On The Management Area Of Typical Benggang

The Jingouxing watershed in Gan County,Jiangxi Province was selected as the research object,this paper studies the soil quality and different types after Benggang management by employing mathematical statistics and evaluation methods like network analysis,principal component analysis,fuzzy comprehensive evaluation based on data collection,in-situ sampling and field investigation.By analyzing the soil physical and chemical property parameters and the spatial distribution of soil quality of the Benggang in the ecological protection management type,the benefit evaluation index system of the three-management type was further selected and constructed from three aspects: ecological benefit,economic benefit and social benefit.Furthermore,by combining the expert scoring combined with multi-level fuzzy methods,a comprehensive benefit assessment of the Benggang of three different management types was made.From the three aspects of ecological benefit,economic benefit and social benefit,9 index systems were selected for comprehensive benefit evaluation,in order to provide a certain reference for the control of Benggang erosion in southern Jiangxi.The control of Benggang has broad prospects for improving the degree of land use and restoration of the ecological environment,and is of great significance to the local social and economic development.(1)In the restoration process,the texture of the soil was loose,with mostly silt content and low clay content.After treatment with measures,the soil nutrient content gradually increased.Meanwhile,with the increase of the treatment period,the overall soil nutrient content showed an obvious upward trend,under the same vegetation type.However,the physical and chemical properties of the soil did not improve much in the initial stage,and the nutrient content index of the shrubland began to increase significantly in the third year,which made the soil structure continuously improved.The order of soil shear strength was as follows: forest > citrus land> shrubland> grassland> eroded area.The shear strength of citrus land was 29.74% higher than that of shrubland.Total pores,capillary pores,clay content and soil saturated hydraulic conductivity were used to establish the prediction equation to characterize the shear strength in the state of soil saturation.The results show that the reliability and prediction accuracy of the equation were higher.(2)Based on the path analysis and the principal component analysis method,the ecological protection-type Benggang soil properties were analyzed.The minimum data set composed of pH,saturated hydraulic conductivity,organic matter and sand content which can explain 81.42% of the soil properties represented.Therefore,it can be used as a reasonable index to evaluate the impact of vegetation restoration on soil quality.By analyzing the comprehensive index values of soil quality of Benggang under different vegetation types,it was found that the comprehensive index of soil quality was the lowest in the middle-slope,which can indicate that the soil quality is poorly restored.Compared with the slope in the erosion area,the comprehensive soil quality index of forest land,citrus land,and shrubland increased by 2.56,2.17,and 1.76 times,respectively.(3)The constructed index system can more reflect the comprehensive benefits of the three management type Benggang(type of ecological protection,type of industrial economical,type of perfect restoration).After water and soil conservation measures,the soil erosion situation has been greatly improved,and the ecological benefits have been significantly improved.Ecological benefits have been significantly improved,in which vegetation coverage and soil fertility index have been improved to varying degrees,which has effectively improved the surrounding ecological environment.The index value of the period for recovery was 4 to 6 years,which can increase residents’ income in a short period of time and thus promotes the local economic development.The comprehensive benefits after control were 0.53,0.66,and 0.52,which were respectively 3.47,3.60,and 3.71 times higher than before.The evaluation values of ecological benefits,economic benefits and social benefits after ecological protection type Benggang management were 0.0548,0.0453,and 0.0518 respectively,and the three contribution rates reach 55.48%,20.92% and 23.60%,respectively.The evaluation values of the benefits of the three control types were all at a medium-high level.