藏北高寒草地生态系统服务价值评估

藏北高寒草地是我国重要的畜牧业生产基地和生态安全屏障.然而,高寒草地退化使生态系统服务功能减弱,生态服务价值降低,不仅严重影响了藏北高原畜牧业生产和牧民生活,而且直接威胁到区域生态安全及东亚水资源安全.因此,本研究在综合考虑草地生态系统的地域差异性、空间异质性和区域经济发展水平差异性的基础上,选择了贡献率较高的12项指标,对藏北那曲不同类型和不同退化程度高寒草地的生态服务价值进行评估.结果表明,藏北那曲地区高寒草地生态系统的年总生态服务价值为1199.07亿元,其中,高寒草原、高寒荒漠、高寒荒漠草原和高寒草甸提供的生态服务价值分别占总生态服务价值的62.9%、1.5%、8.0%和28.1%.从退化程度上看,未退化、轻度退化、中度退化和严重退化草地提供的生态服务价值分别占总生态服务价值的54.9%、29.3%、11.0%和4.8%.

Evaluation of ecological services value of alpine rangeland ecosystem in the northern Tibet region

Alpine rangeland in the Northern Tibetan region of China is not only a valuable base for livestock production, but also plays an important role in the ecological safety shelter zone for China. However, the alpine rangeland degradation makes weakened ecological service function and descended service value, threatening not only the local ecological safety and life of the local residents, but also further ecological security of the down-streams of the rivers. By combining regional difference, spatial heterogeneity, and difference of economic development level at different areas, 12 indicators with high contributions to ecological services function were selected in this study to evaluate the ecological services value of alpine rangeland in the Naqu region of northern Tibet. The evaluation results indicated that the total annual ecological services value of alpine rangeland was 119.907 billion RMB in the Naqu region, in which ecological services value of alpine steppe, alpine desert, alpine desert steppe, alpine meadow accounted for 62.9%, 1.5%, 8%, and 28.1% of the total ecological services value, respectively. This study also showed that ecological services value of original vegetation, slight degradation, moderate degradation, and severe degradation made up of 54.9%, 29.3%, 11%, and 4.8% of the total ecological services value, respectively.