Ecological Environment Quality Evaluation And Safety Pattern Optimization Based On ARSEI And Circuit Theory

The evaluation of ecological environment quality and the optimization of ecological security pattern are of great significance to regional ecological environment protection.The Wuding River Basin has multiple transitional properties and faces multiple ecological pressures.Ecological protection and restoration are related to the ecological protection and high-quality development of the Yellow River Basin.Taking the Wuding River Basin as the study area,with the support of remote sensing and GIS technology,the quality of the ecological environment is evaluated through a comprehensive index system model,and the ecological source areas in high-quality areas are screened by the granular inversion method,and the ecological corridors are extracted by using the circuit theory.Finally,according to the ecological safety network,the key areas for ecological protection and restoration were obtained,and the ecological security pattern was optimized,and a plan for ecological protection and restoration of the basin was proposed to provide support for the healthy development of the basin ecology.The main conclusions are as follows:(1)Based on the Arid Remote Sensing Ecological Index(ARSEI)index,the greenness index,humidity index,heat index,and salinity index were extracted to reflect the ecological environment function of the basin;The ecological structure index(Ecological Structure Index,ESI)was constructed by the vulnerability index and landscape diversity index;the land use stress index,desertification index and soil erosion index were used to evaluate the threats to the ecological environment of the basin.There are significant spatial differences in the quality of the ecological environment in the river basin.From1987 to 2021,there is an overall improvement trend,and there is a local deterioration phenomenon.The environmental quality of the northwest is poor,but the improvement is the largest.The quality of the ecological environment in the southeast is high,but it is unstable.(2)A total of 7 ecological sources were extracted from the high-quality patches of the ecological environment in 2021 by the granular inversion method;the ecological environment quality was added to the resistance factor,and the comprehensive resistance surface was obtained by the AHP,and then the Linkage Mapper module of the circuit theory was used to obtain the comprehensive resistance surface.A total of 12 ecological corridors were extracted,35 ecological "pinch points",7 first-level obstacle points and 14 second-level obstacle points.The northwestern part of the basin is the area with the greatest resistance and the worst ecological environment quality.The ecological foundation of the ecological pinch area is weak,and human interference should be avoided as much as possible,and the decision-making implementation should focus on ecological protection.(3)Based on the quality of the ecological environment and the distribution of the ecological security network,formulate the principle of dividing the ecological security pattern,and construct the ecological protection and restoration zone of the "one area,one belt,one screen".The density of ecological nodes in the ecological function area of the Mu Us Sandy Land is high,and sand control is the main method;the windbreak and sand-fixation belt along the Great Wall has the highest ecological network density and is the main area for ecological environmental protection restoration;The main goal of forest and grass vegetation protection and soil erosion prevention.Extract the pattern optimization zone of ecological optimization area,key improvement area and optimization obstacle area.The ecological optimization area is the radiation channel of ecological corridor protection;the key improvement area is easy to improve and is the starting point of environmental governance;the optimization obstacle area is the key restoration area.