统计与数据科学学院知识库

兰州—西宁地区虽地处我国战略地位突出的西部腹地，但仍存在发展任务重、 发展底子薄，经济、民生和生态之间的矛盾突出的问题。国家安全和国家发展战 略全局离不开该地区的发展，西部地区全面建成小康社会和实现社会主义现代化 也离不开该地区的发展。本文选取《兰州—西宁城市群发展规划》所覆盖的主要 地级市为研究对象，通过构建指标体系并结合 DPSIR 模型框架，对兰州—西宁 城市群的生态安全现状进行评价，并结合空间演变规律对其动态演变进行分析， 最后采用双重差分法分析城市群建设对生态安全带来的影响，为兰州—西宁城市 群的生态安全提供发展的路径和科学的决策。

文章首先梳理了生态安全有关的国内外研究成果和对政策效果检验的各种 理论，并提出文章所需的具体方法与理论。其次对兰州—西宁城市群的区域生态 安全现状进行评价分析，从驱动力层、压力层、状态层、影响层和响应层五个层 次选取指标，建立指标体系，选取熵权-Topsis 法测算出各指标权重，结合综合 评价法测算出兰州—西宁城市群的生态安全水平，定量剖析当前兰州—西宁城市 群的生态安全水平特征以及区域发展的差异性，然后进一步的应用核密度分析法， 分析各城市间生态安全的差异性特征，之后通过标准差椭圆法及观察其重心迁移 规律，分析兰州—西宁城市群在空间上的迁移规律。最后，文章为检验《兰州— 西宁城市群发展规划》对生态安全水平带来的政策效果，采用双重差分模型对其 实施效果进行检验。

研究结果表明：在总体上，兰州—西宁城市群生态安全水平呈现出一种不断 上升的态势，在城市间存在一定的两极分化现象，表现为省会城市生态安全水平 高，其他城市相对较低的特点，并且《兰州—西宁城市群发展规划》的实施也对 兰州—西宁城市群生态安全水平起了促进的政策作用。

Although Lanzhou-Xining region is located in the western hinterland of our country with prominent strategic position, there are still problems of heavy development tasks, weak development foundation, and prominent contradictions between economy, people's livelihood and ecology. The overall national security and development strategy of the country cannot be achieved without the development of the region, and the building of a moderately prosperous society in all respects and socialist modernization in the western region cannot be achieved without the development of the region.This paper selects the main prefecture-level cities covered by the "Lanzhou-Xining Urban Agglomeration Planning" as the research object, evaluates the ecological security status of Lanzhou-Xining urban agglomeration by constructing an index system and combining with the DPSIR model framework, analyzes its dynamic evolution in combination with the spatial evolution law, and finally adopts the difference-difference method to analyze the impact of the construction of urban agglomeration on ecological security. It provides the development path and scientific decision-making for the ecological security of Lanzhou - Xining city cluster.

At first, this paper reviews the domestic and foreign research results on ecological security and various theories on policy effect test, and puts forward the specific methods and theories needed for this article. Secondly, the current situation of regional ecological security of Lanzhou-Xining urban agglomeration was evaluated and analyzed. Indicators were selected from five levels, namely, driving force level, pressure level, state level, influence level and response level, and an indicator system was established. The weight of each indicator was calculated by entropy weight-TOPSIS method, and the ecological security level of Lanzhou-Xining urban agglomeration was calculated by comprehensive evaluation method. Quantitatively analyze the current ecological security level characteristics of Lanzhou-Xining urban agglomeration and the differences in regional development, and then further apply the nuclear density analysis method to analyze the differences in ecological security characteristics among cities, and then analyze the spatial migration law of Lanzhou-Xining urban agglomeration by standard deviation ellipse method and observing the migration law of its center of gravity. Finally, in order to test the policy effect of "Lanzhou-Xining urban agglomeration planning" on the level of ecological security, the paper uses the difference-difference model to test its implementation effect. The research results show that, on the whole, the ecological security level of Lanzhou-Xining urban agglomeration presents a rising trend, and there is a certain polarization phenomenon among cities, which is characterized by the high ecological security level of provincial capital cities and relatively low ecological security level of other cities. Moreover, the implementation of Lanzhou-Xining urban agglomeration planning also plays a policy role in promoting the ecological security level of Lanxi urban agglomeration.