基于自然生态约束评价的县域生态安全格局构建

自然生态条件的空间差异是导致不同地区生态功能差异的重要原因，直接影响区域生态安全。本文以GIS技术为支撑，通过选择地形地貌、特殊生态保护区、区域环境容量等方面的评价指标, 进行自然生态约束的空间分异综合评价，依据评价结果划定生态功能属性不同的地域单元，为建构区域生态安全格局提供方法和理论支撑。文章以安徽无为县为案例进行实证分析，以县域内的23个乡镇为基本评价单元，选择山地、水网密度、湿地、自然保护区、水环境容量、地质灾害等因子，评价自然生态约束的空间差异，结合安徽无为县区域开发的方向,在县域内构建由3个生态源区、5个生态廊道和众多的生态楔构成的县域生态安全格局，最后对县域生态安全格局的建设提出讨论和建议。

Constructing Ecological Security Pattern in County Scope Based on the Spatial Difference of Eco-environmental Restriction

Objective]Research purpose is how to construct and protect the regional ecological security pattern in the county, and carry the eco-regional security structure theory and method a step forward. Method] Application of qualitative and quantitative methods, Supported with GIS, indexes（such as mountain area, water density, etc.） are selected, resorted to the evaluation of subarea by the nature-ecology, adopting the regionalization method of eco-environmental restriction and the ecological functions of the different attributes delineation of geographical units are classfied.Results]The article takes Wuwei County in Anhui Province as the empirical analysis of the case, there are 23 towns and townships as the basic unit in the county scope to be evaluated.The spatial difference of nature-ecology leads to the difference of ecological function and influences the regional ecological security. After evaluating, the regional ecological security pattern is constructed with 3 ecological functional zones, 5 ecological functional corridors and some ecological functional patches in the Wuwei in Anhui Province.Conclusion]Finally, Practice has proved that the technical approach supported with GIS and the evaluation of the county＇s ecological security pattern based on nature-ecology restriction are feasible.At last some policies and suggestions about how to construct the regional ecological security pattern are put forward.