*Article* **The Spatiotemporal Evolution of Ecological Security in Border Areas: A Case Study of Southwest China**

**Zheneng Hu <sup>1</sup> , Meijun Qian <sup>1</sup> , Xianghe Teng <sup>1</sup> , Zhuoya Zhang <sup>2</sup> , Fanglei Zhong <sup>3</sup> , Qingping Cheng <sup>2</sup> and Chuanhao Wen 1,\***

	- zhuoya@swfu.edu.cn (Z.Z.); cqp@swfu.edu.cn (Q.C.)

**Abstract:** Fewer studies on ecological security (ES) in border areas limit the synergistic development of border areas in the context of rapid globalization. The study of ES in border areas of southwest China can enrich the evaluation methods, summarize the knowledge related to ES in border areas, and provide references for similar areas in the world. Therefore, twenty-five international border counties in Yunnan Province were selected to establish a system to evaluate ES; an entropy weight TOPSIS model was used to evaluate the changes in ES from 2004 to 2019. Then, an obstacle degree model was used to diagnose the factors affecting ES. The state of ES was predicted by a gray prediction model (GM) (1,1) in 2025 and 2030. The results show that an improving ES situation presented a spatial distribution pattern of high to low from the southwest to the west and east. Various factors, including fixed assets investment, per-capita fiscal revenue, per-capita GDP, food production, and water regulation, created obstacles to a desirable ES in the study area. Although the ES of border areas will maintain an upward trend under the existing development model, the number of counties that will reach a secure state of ES in 2025 and 2030 is predicted to only be 1 and 2, respectively.

**Keywords:** border area; ecological security; spatiotemporal evolution; sustainable development; Yunnan Province
