Zoning the ecological redline in arid and semiarid regions:Taking Yulin city as an example in the context of an integrated multi-planning
【摘要】 划定生态保护红线是构筑区域生态安全屏障的基础,是经济社会可持续发展的基本保障;干旱半干旱区水资源短缺是威胁区域生态安全的首要因素,生态保护红线划分应切实以保护水资源安全供给为根本。以干旱半干旱区"多规合一"试点地区榆林市为例,通过对关键生态系统服务功能评估和生态敏感性评价,以水资源约束为核心,提出了生态保护红线体系与划分方法。结果表明:(1)榆林市生态保护红线总面积16998.59 km2,占到全市国土面积的39.60%;其中水源涵养功能红线面积5147.15 km2,秃尾河、榆溪河、芦河、无定河上游是水源涵养核心区域,产水总量高达34.57×107m3;丘陵沟壑区和风沙滩区植被覆盖较高的区域生态功能极为重要,其中12.38%和23.25%的国土面积分别提供了50%以上的水土保持功能和防风固沙功能。(2)水源涵养、防风固沙、生物多样性维护功能红线和禁止开发区红线主要分布于西北风沙滩区;南部沟壑区以水土保持功能为主,红线类型较单一。因此,西北风沙滩区的生态保护对榆林市生态安全维护更重要。研究结果可为"多规合一"各类规划间相互矛盾的有效化解提供决策依据,同时为其他干旱半干旱区生态保护红线的划定提供参考。
【Abstract】 Zoning the ecological redline is a key for the regional eological security shelters’ construcation and social-economic sustainable development. Since water resources shortage is an overriding factor threatening ecological security in arid and semiarid regions, zoning the ecological redline should be based on the security of regional water supply in these regions. In this paper, taking Yulin city(a pilot of the integrated multi-planning) as an example, we proposed a method for zoning the ecological redline by assessing the key ecosystem services and ecological sensitivity with the consideration of water resouces constraints. The results indicated that:(1) the area of ecological redline was 16998.59 km2, covering 39.60% of the territory of Yulin city. The area of redline in water conservation was 5147.15 km2, in which the upstream of watersheds in Tuwei River, Yuxi River, Luhe River and Wuding River were the core regions of water supply with an total amount of 34.57×107 m3 water producation per year.About 12.38% of loess area and 23.25% of sandy area contributed more than half of the ecological services of soil and water conservation and sand fixation, repectively, which indicates the importances of these two areas in Yulin city.(2) Sand area in the northwest of Yulin city covered multiple redlines, including water conservation, sand fixation, biodiversity conservation and forbidden development zones, while the loess hilly area in the south covered only the redline of soil conservation. This means that the sandy area may play a more important role in the protection of the regional ecological security of Yulin city compared with the loess hilly area. This study provided a scientific basis for solving the conflicts effectively among various types of planning as well as a theoretical framewok in zoning the ecological redline in other arid and semiarid regions.
【Key words】 ecological redline； water resources； ecosystem services； integrated multi-planning； Yulin city；