Study on Urban Land Ecological Security Pattern and Obstacle Factors in the Beijing-Tianjin-Hebei Region

Land ecological security is the material basis of the sustainable development of human society. The coordinated development of the Beijing-Tianjin-Hebei region is a major national strategy of China. Land ecological security is of great significance to the coordinated development of the Beijing-Tianjin-Hebei region and the maintenance of China's ecological security. In this paper, the pressure-state-response (PSR) model is used to construct an evaluation index system of land ecological security, an entropy-weight technique for order preference by similarity to ideal solution (TOPSIS) method is used to calculate the land ecological security index in the Beijing-Tianjin-Hebei region, and an obstacle degree model is used to reveal the obstacle factors. The results show that the overall level of land ecological security in the Beijing-Tianjin-Hebei region was low, and that the security level presented a pattern of "high in the north and low in the south". The land ecological security level was mainly affected by the state subsystem and response subsystem, and the average index of the pressure subsystem was 0.543, which reached the safe state. The main obstacle factors are per capita grassland area, per capita forest area, green land rate of built-up area, urbanization rate, per capita cultivated land, etc. This study provides a theoretical basis for the construction of the land ecological security system, sustainable utilization of land resources and regional sustainable development in the Beijing-Tianjin-Hebei region and promotes the formation of a benign circulation pattern of land ecosystem and effective prevention and control of land ecological and environmental risks in the region.