基于生态安全格局的山水林田湖草生态保护修复优先区识别——以四川省华蓥山区为例

Identifying priority areas for ecological protection and restoration of mountains-rivers-forests-farmlands-lakes-grasslands based on ecological security patterns: a case study in Huaying Mountain, Sichuan Province

优先区识别,是科学有序推进山水林田湖草生态保护修复工作的重要基础。以山水林田湖草生态保护修复工程之一的四川华蓥山区为例,基于生态系统服务重要性提取生态源地共1392.63 km^2,占华蓥山区总面积的35.60%;结合土地覆被类型与地质灾害敏感性构建生态阻力面,并利用最小累积阻力模型与电路模型提取生态廊道共84条,夹点区域0.1 km^2,含夹点廊道10条;生态保护优先区主要分布在景观破碎化较为严重的广安区境内,以及华蓥山西南端的夹点廊道。以生态修复模拟方法识别障碍点,确定生态修复优先区93.86 km^2,大致分两片。其中,广安区境内受到人类活动干扰的破碎化生态空间,主要生态修复策略为植被恢复与退耕还林;华蓥山、铜锣山、明月山等滑坡、泥石流地质灾害频发区,主要生态修复策略是矿山地质修复与植被恢复。本研究提出生态安全格局构建与生态修复模拟的思路,为山水林田湖草生态保护修复工作提供了可行的定量方法。

Identifying priority areas is an important basis for the scientifically ordered ecological protection and conservation of mountains-rivers-forests-farmlands-lakes-grasslands. Taking Huaying Mountain as the case study area, we extracted 1392.63 km^2 ecological source areas accounting for 35.60% of the total area based on the importance of ecosystem services. Based on the sensitivity of geological hazards and land-use types, the ecological resistance surface was constructed, and 84 ecological corridors were extracted by the minimum cumulative resistance and circuit models. Based on the circuit model, a 0.1 km^2 pinch point area and 10 corridors with pinch points were identified, which were mainly distributed in Guang′an District with severe landscape fragmentation, and the southern end of Huaying Mountain. The effect of ecological restoration was simulated using the method of barriers analysis, and thus, 93.86 km^2 priority areas of ecological restoration were identified. They were mainly located in fragmented ecological areas frequently disturbed by human activities in Guang′an District, where corresponding ecological restoration strategies included vegetation restoration and the transformation of farmland to forest. It also covered areas with frequent geological disasters in Huaying Mountain, Tongluo Mountain, and Mingyue Mountain, with mine ecological restoration and vegetation restoration as the main ecological restoration strategies. This study proposed an approach to construct ecological security patterns, and to simulate the impact of ecological restoration, in order to quantitatively conduct the ecological protection and restoration of mountains-rivers-forests-farmlands-lakes-grasslands.