Quantitative Assessment Of Soil And Water Conservation Functions In The Huaihe River Basin Based On Value Equivalent

At present,the work of soil and water conservation in China in the new period has put forward research needs on how to evaluate soil and water conservation function at regional scale?especially at county level?."Maintaining and improving the function of soil and water conservation"has become one of the important tasks and objectives of soil and water conservation work in our country,and"keeping the soil and water conservation function is not reduce"has also become one of the baseline goals and standards for assessing regional soil and water conservation work.It is of realistic demand and academic value to carry out the research of soil and water conservation function evaluation.To explore the evaluation system and method of county soil and water conservation function,in our research,the typical counties?Shangcheng county and Mengyin county?in Huaihe river basin are selected as the research objects,and the methods of data collection,field investigation and remote sensing investigation are used to explore the value evaluation method of soil and water conservation function at county level by using the"equivalent factor method"of ecosystem service function evaluation.The results of this study are expected to provide a reference for further research on the evaluation of soil and water conservation function value,and provide a basis for understanding the value of soil and water conservation function in the study area.The main results are as follows:?1?Evaluation system of soil and water conservation function value in key prevention and control districtsBased on the principles of highlighting the dominant function of soil and water conservation,focusing on the main land use types,refining land use patterns,and considering the accessibility of functional evaluation indexes,our study partitioned and constructed the evaluation system of soil and water conservation function in the key prevention and control areas of Huaihe river basin:three dominant basic functions were considered in the key prevention areas,and one social and economic function,namely water conservation and soil conservation,ecological maintenance and integrated agricultural production;The key control areas consider three dominant basic functions and one social and economic function,namely soil conservation,water storage and conservation,ecological maintenance and integrated agricultural production.The evaluation units both are farmland,garden land,forest land,water and water facilities land.?2?Modification and calculation method of equivalent factor of soil and water conservation function value at county scaleThe quantitative evaluation of soil and water conservation function value explored in this study is based on the value equivalent method.After establishing the quantitative evaluation system of soil and water conservation function value,based on the basic equivalent scale of ecosystem service value,and after adjusting the parameters of soil conservation,vegetation index,NPP,precipitation and water conservation at the county level,the equivalent scale of soil and water conservation function value is established,which combines the value of soil and water conservation function of one standard unit at the county level?V?and the value of regional land use structure?A?,the function value of soil and water conservation is calculated.?3?Preliminary assessment of the functional value of soil and water conservation in typical counties in key soil and water loss control areasIn 2016,the value of soil and water conservation function of a standard unit in Shangcheng county was 6655.64 yuan/hm².The land use structure value of farmland,garden land,forest land,water and water facilities land were 62889 hm²,5217 hm²,115231 hm² and13725 hm²,respectively.After the correction calculation of soil conservation,vegetation index,NPP,precipitation and water conservation in the county,the total value of soil and water conservation function in Shangcheng county was 2.83×10¹⁰ yuan.Among the basic functions,the value of water conservation function is the highest,accounting for 71.82%of the total value.Water and water facilities land has the highest value of soil and water conservation function per unit area,mainly water conservation function,followed by forest land,garden land and farmland.The value of terrace under the control project is 2782.83yuan/hm² higher than that of sloping land.In 2016,the value of soil and water conservation function of a standard unit in Mengyin county was 5998.89 yuan/hm².The land use structure of farmland,garden land,forest land,water and water facilities land were 58134 hm²,41145hm²,296361 hm² and 7303 hm²,respectively.The total value of soil and water conservation function was 4.89×10⁹yuan after the revised calculation of county soil conservation,vegetation index,NPP and precipitation.Among the basic functions,the value of soil conservation function was the highest,accounting for 16.65%of the total value.Water and water facilities land has the highest value of soil and water conservation function per unit area is 80961.02 yuan/hm²,followed by garden land,forest land and farmland.The value per unit area of the terrace project is 2319.72 yuan/hm² higher than that of the sloping land.The evaluation results of basic functions of soil and water conservation and socio-economic functions in Shangcheng and Mengyin counties generally meet the functional requirements of the state for key soil and water loss prevention and control areas.