基于地质灾害敏感性的生态安全格局关键区识别与修复——以济南市为例

Abstract

区域生态安全格局构建对提升生态系统服务功能提供了重要路径，同时统筹各种生态要素进行生态保护与修复分区也是新时期做好生态修复的重要举措。以济南市为例，基于现状生态系统类型分布，聚焦生态本底和地质灾害敏感性的特征，基于形态学空间格局分析方法和自然保护区结合进行生态源地提取。采用夏季降水、植被覆盖度、坡度3个地质灾害敏感性因子修正基本生态阻力面。并采用最小成本路径方法（Least-Cost Path method，LCP）提取生态廊道，构建了市域的生态安全格局。采用电路理论进行生态关键区域（生态"夹点"和生态障碍点）的识别，进一步划分生态修复改善区，并对此提出针对性的生态保护修复策略和工程措施。研究表明：1）市域生态源地的个数为35个，面积为567.15 km²，主要类型为林地和草地。空间上主要分布南部山区。生态廊道818.42 km，平均廊道长度为12.99 km，廊道分布存在较为明显的空间分布差异性，整体呈现出"一屏、一带、三轴"的生态安全格局。2）识别的生态修复关键区包含生态"夹点"25处，历城区生态"夹点"分布最为密集。全市亟需修复的生态障碍点共34处，面积为6.90 km²，主要分布章丘区。生态改善区共识别2994.84 km²，近期亟需修复的面积为96.1 km²，主要分布在长清区、历城区、莱芜区。3）通过对比生态修复关键区和现状土地利用类型，因地适宜的制定了生态修复策略与工程措施布置指引方向。研究结果可为济南市国土空间生态修复规划提供一定的技术支撑，同时也可为其他地质灾害敏感性区域的生态修复规划提供指引。;Construction of a regional ecological security pattern provides an important path to enhance ecosystem service, while the coordination of various ecological elements for ecological protection and restoration zoning is also an important initiative for better ecological restoration in the new epoch. Taking Jinan city as a case study area, we focus on the basal characteristics of regional ecological environment and geohazard sensitivity based on the current spatial ecosystem distribution, the ecological source area was extracted based on Morphological Spatial Pattern Analysis and nature reserves. In addition, summer precipitation, vegetation coverage and slope three geohazard sensitivity factors were used to modify the basic ecological resistance surface, and the ecological corridors were identified using Least-Cost Path method (LCP), and as a result, the ecological security pattern of Jinan City was constructed. by the application of circuit theory, critical areas of ecological restoration (ecological pinch point and ecological barrier point) were identified and further demarcated into three different ecological restoration zones, for which targeted ecological protection and restoration strategies and engineering measures were proposed towards those restoration zones. Results indicate that there were 35 ecological sources and covered an area of 567.15 km², and the main ecosystem types were forestland and grassland. Those sources were mainly distributed in the southern mountainous. The ecological corridors with a total of 1548.36 km between them, and the average length of the corridor was 12.99 km. All of them constructed a one screen, one belt and three axes ecological security pattern. Key areas of ecosystem preservation and restoration were identified based on the circuit theory, including a total of 25 ecological pinch points, 34 ecological barrier points, and 6.90 km² of it, and the pinch and barrier points mainly distributed in the Licheng and Zhangqiu District, respectively. A total of 2994.84 km² of ecological improvement areas have been identified, with 96.1 km² in urgent need of restoration soon, mainly distributed in Changqing, Licheng and Laiwu District. Suggestions of restoration and direction of engineering measures were proposed, with a combination of the spatial ecological characteristics and land use types. The results of the study provide some technical supports for the territorial spatial planning and ecological protection and restoration in Jinan and also provide scientific guidance for other geohazard-sensitive areas.