The Research On Comprehensive Management Model And Benefits Evaluation Of Small Watershed In Yanqing

Based on the theory of sustainable development, the theory of runoff regulation, the theory of system, principles of landscape ecology, principles of soil and water conservation and principles of ecological economics, a survey was conducted in 21 small watershed of Yanqing County on their management. Statistical methods including cluster analysis, multi-level fuzzy evaluation and Topsis were conducted to the research of management modes and evaluating the effectiveness of small watershed in Yanqing County. Results of this research can be further referenced hence providing scientific basis for soil and water conservation of Beijing(1) Existing problems were revealed in the survey on the masses for their attitudes toward relevant policies in management of small watershed and the effectiveness of the policies. Upon discussion, the idea of people-orientation is proposed. Local people should be encouraged to take part in governance, their living and producing conditions should be improved, and publicity and education should be strengthened.(2) We select the gully density (both total and per capita), per capita arable land, cultivated land, forest area, orchard area, terrace and dam area, the ecological forest area, economic forest area, and controlled area as the indicators of classification, and use cluster analysis method to categorize 21 models of small watershed governance into three types:ecological, agricultural and economic. Among them, the eco-governed 9 small watershed take up 42.9%; agri-governed 2 small watershed accounts for 9.5%; econ-governed 10 small watershed take up 47.6%. Based on the canonical example of three types of small watershed, the management models were introduced.(3) Six typical elements related to net income Per capita in management of small watershed are aligned into order:investment (0.724)> controlled area (0.711)> soil and water conservation engineering (0.648)> economic forest (0.590)> water conservation forest(0.536)>land preparation (0.508).(4) Weight values of AHP-benefit are:ecological benefits:0.5299, economic benefits:0.3497, social benefits:0.1204. The total level of sorting CI= 0.0751 meet compliance requirement (CI<0.1), and weights of each factor meet evaluation requirements, and thus indicators of the total order is correct. Weight of governance level:0.2920, grass coverage:0.0966, soil erosion modulus: 0.1413; economic benefits of labor productivity:0.0878, land productivity:0.0545, per capita net income:0.2074; social benefits in the weight of grain per capita:0.0160, basic farmland per capita:0.0558, the labor utilization rate:0.0485. According to the feedback of weight order, in the management of small watershed of Yanqing County, the level of small watershed management, per capita net income, soil erosion modulus are the main factors.(5) With multi-level fuzzy evaluation method, it can be concluded that the eco-governed and econ-governed watersheds have better ecological and economic benefits, ecological benefits achieved average or good; to agri-governed small watersheds are less desirable, both ecologically and economically. As more attentions are paid on soil and water conservation and ecological construction, three types of models of small watershed management have certain social benefits, among which the most outstanding is Foyukou watershed of total evaluation of 92 points.(6) The linear regression of multi-level evaluation method and evaluation of Topsis scores relatively high (R2= 0.8853). Two methods in evaluation of small watershed management efficiency have certain extent of reliability, and can provide scientific basis for effective evaluation of small watersheds in Yanqing County.