北京市生态安全格局保护紧迫性分级

以北京市为例, 通过粒度反推法和景观连通性识别重要生态用地, 通过邻域分析法构建生态阻力面, 采用MCR模型构建北京生态安全格局, 利用人工神经网络计算建设用地扩张概率, 对构建的生态安全格局进行保护紧迫性分级。结果表明, 北京市重要生态用地面积为 6488.53 km², 主要分布在西部和东北部山区, 小部分位于东南平原。一级生态用地面积为4482.48 km², 主要分布在西北和西南地区; 二级生态用地面积为1338.27 km², 主要分布在西部远郊山区、西南部近郊平原和东南部平原; 三级生态用地面积为669.77 km², 主要分布在中北部和东南部平原。重要生态廊道长度为2410.47 km, 分布在远郊城镇以及城乡交界处。一级生态廊道长度为1477.63 km, 主要分布在西北和西南远郊山区; 二级生态廊道长度为390.91 km, 主要分布在远郊平原的生态用地附近; 三级生态廊道长度为 541.93 km, 主要分布在城市中心的周边地区, 呈环状包围中心城区。

Urgency Classification of Beijing Ecological Security Pattern Protection

Taking Beijing as an example, the granularity back-calculation method and the landscape connectivity index were combined to identify important ecological land. The neighborhood analysis was adopted to construct the ecological resistance surface, whereas the minimum cumulative resistance model was used to construct the ecological security pattern. The probability of land expansion calculated through an artificial neural network was used to classify the ecological security pattern of construction. The results show that the important ecological land area of Beijing is 6488.53 km², mainly distributed in the mountainous areas of western and northeastern Beijing, and a small part is located in the southeast plain area. The primary protection ecological land area is 4482.48 km², mainly distributed in the northwest and southwest. The secondary protection ecological land area is 1338.27 km², which is mainly distributed in the western suburbs, the suburban plains in the southwest and the plains in the southeast. The third-level protection ecological land area is 669.77 km², mainly distributed in the north-central and southeast plains. The important ecological corridor is 2410.47 km long and is distributed in the outer suburbs and urban-rural junction. Among them, the length of the first-class ecological corridor is 1477.63 km, mainly distributed in the mountainous areas of the northwest and southwestern suburbs; the secondary ecological corridor is 390.91 km, which is mainly distributed near the ecological land of the outer suburb plain; the third-level ecological corridor is 541.93 km, mainly distributed in the surrounding area of the city center, surrounded by the central city.