Spatial-temporal Variations Of Water Resources Security And Obstacle Factors In The Changbai Mountain Area From The Perspective Of Water Footprint

Water resources security is a matter of national economic development,social stability and ecological security.With the rapid development of China’s economy,coupled with continuous increase in water consumption,has caused the contradiction between the supply and demand of water resources to intensify.Simultaneously,the problems of water pollution and water quality deterioration are becoming increasingly prominent,which have a significant impact on China’s food security,ecological and environmental security and economic security,and water resources management is facing a major challenge.Water resources security is both the core content and the ultimate goal of water resources management.Conducting a water resources security assessment can identify regional water resources security issues,while providing a scientific basis for regions to make water resources-related decisions.The Changbai Mountain area is the origin of the Songhua River,Yalu River,and Tumen River,and is also an important water resources protection area in Jilin Province and even in Northeast China.Although the abundant water quantity provides a guarantee for the development of the Changbai Mountain area,the level of its water resources development and utilization and the changes in the water ecological environment are closely tied to the water resources security of the source area and the middle and lower reaches.Therefore,identifying its water resources security issues is not only beneficial to the high-quality development of the region but also to the protection and rational allocation of water resources in Jilin Province and Northeast China.In this paper,we use water footprint as an indicator to carry out water resources security evaluation in the Changbai Mountain area,analyze the problems of water resources security in the area,and propose countermeasures to solve them,so as to provide reference and reference for water resources security evaluation and sustainable utilization in water-abundant areas.In this paper,based on accounting for the blue,green,and grey water footprint of agriculture,industry,life,and ecology in the Changbai Mountain area from 2000 to 2019,the spatial and temporal changes of water footprint in the Changbai Mountain area are analyzed;combined with the core meaning of water resources security and related requirements,a total of 13 indicators are selected from three criteria layers,namely water quantity security,socio-economic security,and water ecological environment security,to establish a comprehensive evaluation of water resources security in the Changbai Mountain area.The weight of each indicator is determined by combining the analytic hierarchy process and the entropy weight method;the level of each indicator is defined according to the threshold value of relevant evaluation standards;the evaluation model of water resources security in the Changbai Mountain area is established according to the multi-level fuzzy comprehensive evaluation method to evaluate the level of regional water resources security and analyze its dynamic change characteristics;the obstacle degree model is used to identify the obstacle factors of water resources security in the Changbai Mountain area and put forward.The model will be used to identify the obstacles to water resources security in the Changbai Mountain area and propose countermeasures and suggestions.The main findings are as follows:(1)From 2000 to 2019,the annual average total water footprint of the Changbai Mountain area is 382.54×10~8m~3,showing a trend of"fluctuating up and then slowly decreasing".The proportion of blue,green,and grey water footprint in the total water footprint is ranked as follows:grey water footprint>green water footprint>blue water footprint,in which both green and grey water footprint is gradually decreasing,and the rate of decrease of grey water footprint is the fastest compared with the two,while the blue water footprint is slowly increasing.Among the sectoral water footprint,agricultural water footprint,industrial water footprint,and domestic water footprint all show a decreasing trend,while the ecological water footprint shows an increasing trend;the proportion of the total water footprint is ranked as follows:agricultural water footprint>domestic water footprint>industrial water footprint>ecological water footprint.The spatial distribution pattern of water footprint is"high in the west and low in the east",and the spatial differences are obvious.(2)From 2000-2019,at the regional scale,the water quantity security level in the Changbai Mountain area wasⅠ;the socio-economic security was improved fromⅢtoⅡ;and the water ecology and environment security level wasⅢin most years.The level of water resources security in the Changbai Mountain area from 2000-2019 gradually changed from the general security level(Ⅲ)to the safer level(Ⅱ).On the county scale,the water quantity security level is maintained above level II,and the socio-economic security level is increased from 9 counties in 2000 to 12 counties in 2019;the water ecological environment security level is"better in the east than in the west"in the distribution pattern.In general,the eastern water resources security level isⅡor higher,while the western water resources security level is lower than the eastern,ⅢorⅢor below.(3)The obstacle factors affecting the improvement of water resources security level in the Changbai Mountain area exhibit variability.At the guideline level,socio-economic security has been the main factor limiting the improvement of water resources security level in the Changbai Mountain area,and the level of socio-economic security obstacle degree in most counties is medium-high obstacle degree or high obstacle degree.In terms of obstacle factors,water production modulus,crop water production efficiency and ecological water footprint ratio are the main obstacle factors,among which crop water production efficiency has the highest obstacle level.The obstacle factors also exhibit spatial variability.The main obstacle factors in the eastern parts of the Changbai Mountain area are the proportion of ecological water footprint,while the main obstacle factors in the western parts are crop water production efficiency and water production modulus.(4)In order to enhance the level of water resources security in the Changbai Mountain area,we should adjust the crop planting structure and improve the yield per unit area of crops;give full play to the advantages of local resources and develop special agricultural products and livestock breeding,at the same time,we should pay attention to strengthening the supervision of pesticide and chemical fertilizer application to avoid environmental pollution and achieve green and low-carbon development in agriculture;increase the investment in water for urban ecological environment and promote the innovation and application of recyclable water recycling technology.