Evaluation Of Land Ecosystem Health In Shaanxi Province Based On DPSIR-TOPSIS Model

Land resources are the material basis of human production and development.With the rapid economic development and society,due to the unreasonable use of land resources,the land ecological environment has gradually deteriorated,the land quality has declined,the land ecological environment has suffered tremendous pressure and threat,and the contradiction between man and land has become increasingly prominent.Therefore,carrying out regional land ecosystem health assessment research is of great significance for scientific management of land resources,optimization of land ecological construction and protection,and it is also a hot topic of land science research.In this study,Shaanxi Province was taken as the research object.Based on the review at home and abroad,the evaluation model of “ driving force – pressure – state– influence – response ” was constructed.According to the status quo of the area,20 evaluation indexes were selected from three aspects of natural factors,social factors and economic factors to construct the index evaluation system.At the same time,the entropy weight method and TOPSIS model were used to calculate the health index of land ecosystem.The obstacle degree factor was determined by the obstacle degree diagnosis model,and the improvement measures were put forward according to the evaluation results.The main results show that:(1)From 2010 to 2019,the health status of the land ecosystem in Shaanxi Province fluctuated greatly,and it was generally in a critical health state.In the past ten years,the land ecosystem had experienced unhealthy,critical and sub-health states.Among them,2014 was the best year for land ecological health in Shaanxi Province,which was in sub-health state.(2)From the subsystems of DPSIR model,the health index of driving force subsystem,state subsystem and influence subsystem showed an upward trend,which was in a critical state and sub-health state as a whole.The health index of pressure subsystem and response subsystem showed a downward trend.In 2014 and 2016,the response subsystem and pressure subsystem reached a healthy state respectively,and the rest were in an unhealthy state and a critical state.(3)From 2010 to 2019,the changes of land ecosystem health in Tongchuan,Baoji and Weinan were large,while those in Xi ’an,Xianyang and Yangling were small.Among them,Xi ’an,Xianyang,Hanzhong and Ankang had a higher level of land ecosystem health,while Tongchuan,Weinan and Yan ’an had a relatively low level of land ecosystem health.The problem of ’ regional differentiation ’ of land ecosystem health in Shaanxi Province was prominent.The health status changed in Guanzhong area were complex,and the health status changed in northern and southern Shaanxi were simple.(4)According to the evaluation results and obstacle factor diagnosis model,the main obstacle factors restricting land ecological health in Shaanxi Province were the proportion of tertiary industry to GDP,forest coverage,per capita arable land,the use of agricultural plastic film per unit of arable land,effective irrigation area index and chemical fertilizer load per unit of arable land.According to the actual problems faced by the land ecosystem in Shaanxi Province,put forward suggestions and measures for improvement.