Study On Evaluation Of The Construction Of Ecologically Clean Small Watershed In Danjiangkou Reservoir Area In Hubei Province

In recent years,due to the rapid development of urbanization,problems such as the deterioration of the ecological environment,the increase of soil erosion,and the serious pollution of water bodies have become increasingly prominent.In 2006,the Ministry of Water Resources proposed the concept of ecologically clean small watersheds.The Danjiangkou reservoir area in Hubei Province is the head of the middle route of the Southto-North Water Transfer Project.Its water environment safety is extremely important.In order to solve the ecological and environmental problems in the reservoir area,Hubei Province has been vigorously promoted by the Ministry of Water Resources,the provincial government and water conservancy departments at all levels.,Continue to promote the construction of ecologically clean small watersheds in the Danjiangkou Reservoir Area.Currently,7 ecologically clean small watersheds have been successfully constructed,and an ecologically clean small watershed governance model that conforms to local conditions has been initially formed.However,as the "Plan for Soil and Water Conservation of Hubei Province(2015-2030)" incorporates the construction of ecologically clean small watersheds into the important content of the plan,the future construction of ecologically clean small watersheds will become larger and larger.However,the Danjiangkou reservoir area in Hubei Province is currently There is no evaluation index system to guide the construction of ecologically clean small watersheds.In order to better guide its construction work and improve construction efficiency,it is necessary to establish a scientific,easy and local construction evaluation index system.Therefore,this article takes the Danjiangkou reservoir area in Hubei Province as the research object,and puts forward an evaluation index system for the construction of ecologically clean small watersheds that can be promoted and applied in the Danjiangkou reservoir area in Hubei Province..The main research conclusions are as follows:(1)Constructed an evaluation index system for the construction of ecologically clean small watersheds.The index system includes three parts: the target layer,the criterion layer,and the index layer.The target layer is the evaluation of the construction of ecologically clean small watersheds in Hubei Province,and the criterion layer includes B1 soil erosion prevention and control.Targets,B2 non-point source pollution prevention and control targets,B3 human settlements remediation targets,and B4 social and economic sustainable development targets;the indicator layer includes C1 forest and grass coverage rate,C2 soil erosion modulus,C3 livestock and poultry farming sewage treatment rate,C4 chemical fertilizer application intensity,C5 pesticide application intensity,C6 water quality,C7 channel hydrological form,C8 riparian vegetation coverage rate,C9 domestic waste treatment rate,C10 domestic sewage treatment rate,C11 rural living toilet penetration rate,C12 village beautification and greening rate,C13 channel flood discharge capacity,C14 farmers per capita net income,C15 population density,a total of 15 indicators.(2)Using the group decision-making function judgment consensus matrix of the yaahp software to determine the weights of the criterion layer and the index layer,the result of the criterion layer weight is: B1 soil erosion control target(0.5063)>B2 non-point source pollution control target(0.2944)>B4 society Sustainable economic development target(0.1270)>B3 Human settlement environment improvement target(0.0723).The result of the index layer weighting is: C2 soil erosion modulus(0.3980)>C7 water quality(0.1340)>C1 forest and grass coverage rate(0.1083)>C14 farmers’ per capita net income(0.1082)>C5 livestock breeding wastewater treatment utilization rate(0.0721)>C11channel flood discharge capacity(0.0396)>C4 chemical fertilizer application intensity(0.0329)>C3 pesticide application intensity(0.0294)>C15 population density(0.0188)>C9 village sewage treatment rate(0.0143)>C8 riparian vegetation coverage rate(0.0134)>C6 channel hydrological pattern(0.0125)>C12 rural living toilet penetration rate(0.0103)>C10 village household garbage innocuous treatment rate(0.0053)>C13 village beautification and greening status(0.0028),based on this The indicators are quantified,and the scoring standards for the indicators are finally determined.(3)The situation before and after the construction of the Qingshui River’s ecologically clean small watershed was evaluated.The evaluation result is: the overall score before the construction is 45 points,the evaluation result is poor,the development of the small watershed before the construction is still in a disordered state,and the ecological clean The basins are quite different;the overall score is 72 points after construction,reaching a good level,and the ecologically clean small basins are generally well constructed.