中文摘要：

青藏高原高寒草地是我国重要的畜牧业生产基地和生态安全屏障。高寒草地退化不仅影响了当地畜牧业生产和牧民生活，而且严重地威胁着我国和东亚地区的生态安全。从高寒草地生态系统的生态、生产和生活功能角度出发，分析了青藏高原高寒草地生态系统在人口、放牧压力与资源环境承载力的相互作用关系，及其生态、生产和生活功能比例结构变化对高寒草地生态系统服务功能的影响，阐明了高寒草地生态系统服务功能的多元耦合、多维连锁和多重反馈的相互作用机制。并以藏北那曲地区为例，把2008年农牧民脱贫线和小康线作为生活功能标准，通过生态服务功能当量，确定了维持高寒草地生态系统可持续发展的生态、生产和生活功能比例结构。据此，估测了牧民的生活功能达到脱贫线和小康线标准时允许的人口承载量。结果表明，高寒草地退化使草地生态系统的人口承载量下降了60％。以那曲地区2008年的实际的牧业人口量与允许的人口承载量相比，高寒草地退化后，实际牧业人口占脱贫标准的36％，但小康标准超载了118．9％。因此，调控人口承载量是实现青藏高原高寒草地生态系统的生态、生产和生活功能协调发展的关键。

英文摘要：

Rangelands of the Qinghai-Tibetan Plateau is an important base for livestock production and shelter for the ecological safety in China. The degradation of alpine rangeland in the Qinghai-Tibetan Plateau has not only impacted local livestock production and people＇s quality of life, but also seriously damaged the ecosystem security of China and Southeast Asia. By analyzing the function of ecology, production and livelihood （FEPL） of alpine rangeland ecosystem, this study examines inter-relationship between population and grazing pressure and environmental carrying capacity of alpine rangeland ecosystem, as well as the structural change of FEPL and its effect on service function of alpine rangeland ecosystem, and illustrates the alpine rangeland ecosystem＇s FEPL and its internal relation of polybasic coupling, multidimensional and multiple feedbacks. Using the Naqu region of northern in the linkage Qinghai-Tibetan Plateau as an example, this study utilizes the annual per-capita income of well-to-do society and overcome-poverty line for the herdsman proclaimed by Chinese government in 2008 as standard livelihood function and establishes an appropriate structure for the FEPL of alpine rangeland ecosystem based on the equivalent of the ecological services function under the different economic conditions that can maintain sustainable development of alpine rangeland ecosystem. The results show that the degradation of alpine rangeland has caused a 60% decrease of the population carrying capacity in the region. For example, the current population carrying capacity in the Naqu region in 2008 accounted for 36% and 118.9% of estimated population carrying capacity in the overcome-poverty life line and well-to-do society, respectively. Therefore, controlling population carrying capacity is the key for mutual development of the FEPL of alpine rangeland ecosystem in the Qinghai-Tibetan Plateau.