Secondary fuzzy comprehensive evaluation model for ecosystem health of irrigation district and its application

The unreasonable development of traditional irrigation district has an adverse effect on the ecosystem environment. Therefore, a new ecological model of irrigation district is needed urgently to meet the requirement of the sustainable development of irrigation district. In this paper, the connotation of the ecosystem health of irrigation district was studied. According to the connotation of the ecosystem health of irrigation district and the principle of index selection, four independently typical sensitivity indices were adopted in order to develop an evaluation index system of ecosystem health of irrigation district. The four indices included the structure attribute, the environmental element, the integrated function element and the social and economical element of ecosystem of irrigation district. A secondary fuzzy comprehensive evaluation method based on the integration of analytic hierarchy process and fuzzy mathematics was used to develop an evaluation model of ecosystem health of irrigation district. The model was applied in the Beiyechang reclaimed water irrigation district in Beijing. Results showed that the model reasonably well represented the status of ecosystem health of Beiyechang reclaimed water irrigation district. Thus the model can evaluate ecosystem health of irrigation district.