Research On Ecological Security Evaluation And Obstacle Factors Of The Yellow River Basin

The Yellow River Basin is an important ecological barrier and economic zone in China,it plays a vital role in national economic and social development and ecological security.However,due to the long-term impact of natural environmental conditions and high-intensity development,the ecological environment of the basin is more fragile,the ecological security level is lower,and the conflict between economic development and resources and environment is still prominent.The proposed ecological protection and high-quality development of the Yellow River Basin in 2019 as a major national strategy provides great opportunities for the development of the provinces along the basin.Therefore,this study takes the high-quality development of the Yellow River Basin as the background,and takes into account the actual situation of socio-economic,natural resources and ecological environment in each region of the basin,firstly,based on the "Driver-Pressure-State-Impact-Response "(DPSIR)theoretical framework model to construct the ecological security evaluation index system of the Yellow River Basin,followed by the TOPSIS fuzzy element method to measure the ecological security status and its evolution trend of each province along the Yellow River Basin from 2010 to 2019;Furtherly,introducing the theory of coupling degree and coupling coordination model to conduct a comprehensive and systematic evaluation of the temporal and spatial differences in coupling and coordination between the overall internal system of the Yellow River Basin and the ecological security level of the two subsystems;Finally,using the obstacle degree function to quantitatively study the main obstacle factors that affect the improvement of the ecological security level of the Yellow River Basin,systematically and comprehensively reveal the current status and causes of the ecological security of the Yellow River Basin.The results of the study show that(1)the ecological environment of the Yellow River Basin provinces and regions has been improving from2010 to 2019.In terms of time series,the overall ecological safety level of the Yellow River basin has experienced three processes: "small increase-rapid increase-stable increase";in terms of spatial pattern,due to natural,regional and historical factors,the ecological safety level of the provinces along the Yellow River basin has evolved from "leading in the middle reaches" to "surpassing in the lower reaches".In terms of spatial pattern,due to natural,regional and historical factors,the ecological safety level of provinces along the Yellow River Basin has evolved from "leading in the middle reaches" to "surpassing in the lower reaches".(2)The overall coupling and coordination level of ecological security in the Yellow River basin from 2010 to 2019 is on the rise,and the coupling and coordination has undergone the transition of "barely coordinated-primary coordination-intermediate coordination",with obvious spatial differences in the coupling and coordination ability of different regions in the upper,middle and lower reaches of the basin;the coupling and coordination between the two subsystems from 2010 to2019 are coordinated in a healthy and orderly direction,but show obvious regional heterogeneity,and the internal synergistic mechanism of the ecological security system needs to be improved.(3)By exploring the causes of differences in ecological security levels among different provinces in the Yellow River basin through a barrier function model,we found that there are not only common factors that impede the improvement of ecological security levels in each province in the basin,but also regional heterogeneity in the barriers to ecological security in different provinces.Water resources per capita is a common obstacle to the improvement of ecological security in all provinces and regions along the basin.