我国典型陆地生态系统固碳重要区范围界定

全球变暖已成为当今最主要的全球性环境问题之一,建立固碳重要区也是应对全球气候变化的重要途径之一.根据我国陆地生态系统现状以及固碳相关的最新研究结果和政府文件,以森林、草地生态系统为主要研究对象,采用GIS空间叠置分析方法,界定我国典型陆地生态系统固碳重要区(注:涉及“全国”的各要素范围均未包含港澳台地区)的空间范围.研究结果:固碳重要区评价指标体系包括生态系统碳储量、碳汇和固碳潜力3个核心因子,界定过程包括界定范围选择、固碳高值区识别、固碳重要区范围确定和分区命名等步骤.在全国尺度界定了森林、草地两大类共计20个固碳重要区,总面积285.6×104 km2.其中,森林生态系统固碳重要区主要分布在我国东北部、西南部的深山区和东南部的山地丘陵,草地生态系统固碳重要区主要分布在内蒙古高原中东部、新疆西北部山地和青藏高原东南部.固碳重要区面积占全国国土总面积的29.8%,所提供的NPP(净初级生产力)量占全国NPP总量的40.7%,固碳能力是全国平均水平的1.37倍.固碳重要区范围界定结果符合“以较小面积获取较大服务”原则,适于作为我国实现碳减排目标的优先保护区域. 

Delimiting Important Carbon Sequestration Areas for Typical Terrestrial Ecosystems in China

Global warming is currently one of the most significant global environmental issues. The construction of important carbon sequestration areas (ICSA) is an important way to address global climate change. Using GIS spatial overlay analysis and taking the forest and grassland ecosystems as the study objects, this paper selected three factors, which included the spatial distribution of typical terrestrial ecosystems in the year 2000, the latest research results of carbon sequestration and government documents, to define the location of ICSA of typical terrestrial ecosystems all over China (the study area does not include Hong Kong, Macao and Taiwan). The results indicated that terrestrial carbon pool, carbon sink and carbon sequestration potential are the key indices to constructing an assessment index system of ICSA. The determining process mainly included the following steps:(1) a reasonable selection range was given; (2) the highest value areas of terrestrial carbon pool, carbon sink and carbon sequestration potential were determined; (3) the location of ICSA was defined; and, (4) the nominative method of each ICSA was provided. Twenty ICSAs including forest ecosystem and grassland ecosystem were defined, with a total area of 285.6×104 km2. Twelve forest ecosystem ICSAs were distributed in mountainous and hilly areas of the northeast, southeast and southwest regions of China, and the other 8 grassland ecosystem ICSAs were distributed in mid-eastern Inner Mongolia Plateau, mountainous areas of northwest Xinjiang and southeast Tibetan Plateau. The 20 ICSAs accounted for 29.8% of Chinese territory. However, they can protect 40.7% of the total NPP values of China, and their carbon sequestration capacity is 1.37 times the average carbon sequestration level of terrestrial vegetation in China. Therefore, the results are in conformity with the principle of ′smaller areas get larger ecosystem services′. The ICSAs can be regarded as priority conservation areas to achieve the carbon emission reduction target in China.