| Research on river basin ecological security is the basis for protecting the aquatic ecological environment and maintaining harmony between man and nature,and is also a key link in realizing the strategy of sustainable development.The Aksu River Basin is an important part of the Tarim River Basin,one of the areas with the most sensitive ecological environment and the most fragile ecosystem,and its ecological security has a significant impact on Xinjiang’s sustainable economic and social development.Based on the current situation,the improved three-dimensional ecological footprint model was further used to systematically analyze the dynamic change characteristics of the ecological footprint and predict it,and the results showed that with the change of time,the ecological footprint value of the basin increased,the ecological carrying capacity decreased,the ecological deficit continued to expand,the footprint depth deepened,the footprint breadth fluctuated,the consumption of natural resources continued to rise,but the occupation degree gradually decreased.According to the analysis results,the ecological security of the river basin has been seriously unsustainable,the security situation has further deteriorated.The main research results are as follows:(1)The fuzzy comprehensive evaluation method was used to analyze and evaluate the current situation of the bearing capacity of the river basin,which is currently in an overload state.Construct an evaluation index system including l target layer,4 criterion layers and 16 indicators,Using analytic hierarchy combined wih entropy weight to determine indicator weights,and determine that the overall river bain is in an overloaded state according to the principle of maximum membership and the comprehensive assessment value of the calculation results,the carrying capacity of water resources in each subsystem is suitable,and the demand can be met under the current state,the carrying capacity of the water environment is seriously overloaded,the ecological carrying capacity is overloaded,the socio-economic carrying capacity is overloaded,and the pressure of water environment,ecology and socio-economic aspects is greater.Among the selected indicators,the maximum allowable pollution holding capacity of the water functional area,the proportion of irrigation area,the proportion of river wetland area,the unilateral water GDP,and the water consumption of 10,000 yuan of industrial added value have serious impacts on the bearing capacity.(2)Using the improved three-dimensional ecological footprint model to analyze and predict the footprint of the Aksu River Basin,the local population’s demand for natural resources has been further enhanced,and its consumption has gradually expanded.Based on the "national hectare",the improved equilibrium factor and yield factor were used to calculate the ecological footprint index of the river basin,and the gray GM(1,1)model was used for prediction.The river basin showed an upward trend,and the overall trend of per capita ecological carrying capacity decreased.The basin was in an ecological surplus in the nineties,after which it gradually turned into an ecological deficit.The per capita footprint depth is between 1～4,and the flow of natural resources in the basin can no longer support the consumption demand for natural resources in the basin,sustainable development is threatened,and the temporal and spatial changes within the basin are unbalanced.The per capita footprint breadth of the river basin showed a fluctuating downward trend as a whole,and the spatial distribution was obviously different.Among the prediction results,the overall per capita ecological footprint of the river basin basically showed an upward trend,with the fastest increase rate in Wensu County and the slowest in Ahaiqi County.The predicted trend of per capita ecological carrying capacity in the basin is a slow decline,and only Wushi County in the northwest of the basin shows a slow increase,and the rest are declining.In the future,the overall per capita deficit of the river basin showed an upward trend,only Ahaiqi County was in an ecological surplus state,and the rest were ecological deficit status.(3)The ecological security characterization index was selected to analyze and predict the ecological security status of the river basin,and the ecological pressure of the river basin gradually increased,and the safety situation further deteriorated.During the study period,the ecological security status of the Aksu River Basin was evaluated and analyzed from the four perspectives of sustainable development,resource utilization efficiency,ecological security and ecological sustainability,and the sustainability and safety level of the basin were predicted.The results show that the sustainability degree of the river basin gradually changes from weak sustainability to serious unsustainability,and the ecological burden of most areas in the river basin is relatively serious,and a few cases are better.The ecological footprint of 10,000 yuan of GDP in the river basin has a significant downward trend,and the consumption of resources per unit of GDP has been greatly reduced.The watershed changed from a safe state to a mildly unsafe state,and most areas in the watershed were in a safe and relatively safe state.The basin stock flow index has gradually increased,and the current stock capital has completely replaced the flow capital.In the prediction results,only Ahaiqi County in the western part of the basin has been weakly sustainable,and most other areas are seriously unsustainable,and the ecological security level of the overall basin has changed from mild insecurity to severe insecurity,and the ecological security warning level has been further improved,from light police to heavy police.Corresponding regulatory measures must be taken to curb the further deterioration of the ecological security of the river basin in response to the early warning results. |
