摘要
我国土地退化严重,且大部分发生在干旱半干旱地区。恢复为何种生态系统类型是生态学研究的重要课题。采用生态功能区划,根据各个生态功能区主体生态系统功能,推导发挥此功能的生态系统类型的方法,识别关键生态系统类型。以内蒙古自治区和林县为例,采用文献调研、实地调查、3S技术等方法,在评价该县生态敏感性、生态服务功能重要性的基础上,将该县划分为3个一级生态区,11个二级生态功能区。根据各个生态功能区的主体生态系统服务功能,分析发挥该功能的可能生态系统类型。再根据全国自然植被区划、气候变化趋势模型以及现状植被类型,识别各个生态功能区的关键生态系统类型。
Land degradation is widely distributed in China, mostly in arid and semi-arid areas. Identifying which ecosystem types can be achieved through ecological restoration processes is key to ecological restoration success. This is the research focus of ecology subject. Taking the Helin County of Inner Mongolia, located in the semi-arid area of northern China, as an example, this article explores the method to identify key ecosystems through ecological functional zone planning, accompanied with an analysis of existing vegetation surveys, climate change and national vegetation regionalization. By integrating methods of document collecting, field surveys and 3S technology, based on analysis of eco-sensitivity and eco-services, Helin County is classified into three eco-regions, and 11 sub eco-regions. The eco-regions are decided by topographic features, and the role which Helin County plays in the national ecological function regionalization of China. In the national ecological function regionalization, the ecosystem services in Helin County are soil conservation （in most areas）, agricultural products supply, and mountain water-source conservation （in small areas）. The ecological score of how precipitation, slope degree, slope aspect, soil texture and vegetation index contribute to soil erosion sensitivity in the region is calculated and the sum of these values with different weights is regarded as the value of soil erosion ecological sensitivity. The contribution of drought index, soil type, drought index after 50 and 100 years, and vegetation cover to land desertification also are quantified and summed into values of land desertification ecological sensitivity. Then a value for protection importance of the ecosystem is calculated, and a value for water supply is calculated through hydrologic analysis. The sub eco-region is formed by the ecological sensitivity of soil erosion and land desertification, the protected value of ecosystem, and the function of water supply. Areas with the same ecological value and ecological problems are put into the same sub eco-region. On the basis of the main ecosystem service function of every sub eco-region, the possible ecosystem type which produces such functions can be deduced. The vegetation types of Helin County were classified according to the Vegetation Zoning of China, a vegetation zoning map considering climate, soil and water factors, and were used for the deduction of key vegetation ecosystems. Vegetation ecosystems existing in the national vegetation zoning classification should be restored. The locations of ecological restoration should be limited to areas in which the vegetation ecosystem is different to the key ecosystem. The vegetation change under climate change is also simulated. An ecosystem that is different from the key ecosystem should not be included in ecological restoration if it will be the same as a key ecosystem after 50 or 100 years. Compared with existing vegetation identified by field surveys, where ecosystems are obviously different from the key ecosystem, they should be restored. With these steps, the potential key vegetation ecosystems can be identified.
出处
《生态学报》
CAS
CSCD
北大核心
2013年第6期1822-1831,共10页
Acta Ecologica Sinica
基金
中央民族大学985项目(MUC98504-14,MUC98507-08)
国家民委科研项目
高等学校学科创新引智计划(2008-B08044)
关键词
半干旱区
生态功能区
生态恢复
关键生态系统
和林县
semi-arid area
ecological function region
ecological restoration
key ecosystem
Helin County
