中文摘要：

近年来，青藏高原高寒草甸生态系统呈现退化的趋势。本文利用中国科学院海北高寒草甸生态系统定位站多年观测的长时间序列数据，采用定量方法度量高寒草甸自然生态系统的恢复能力，评估该系统的持久性，并结合系统现状提出避免系统崩溃的对策。结果表明，高寒草甸净初级生产力的动态行为以对降水和气温的即时直接响应为主。无论是净初级生产力对自身的“记忆”程度，还是主要气候因子对初级生产力的“滞后”作用，均比较微弱，说明高寒草甸生态系统有较强的恢复能力，即有较强的持久能力。与世界其他地区草地生态系统恢复能力度量结果相比较，高寒草甸生态系统显示较强的恢复能力。科学地利用高寒草地资源，积极恢复治理退化草地，是维持脆弱的高寒草甸生态系统持久的关键。

英文摘要：

The alpine meadow ecosystem on Qinghai-Tibetan Plateau has been degrading in recent years. Based on the long-term observation data about aboveground net primary productivity, yearly precipitation, yearly mean air temperature, and the mean precipitation and air temperature in growth season collected from Haibei Alpine Meadow Ecosystem Research Station, this paper assessed the restoration capability of alpine meadow ecosystem in Haibei Area of Qinghai-Tibetan Plateau, aimed tO provide scientific information and suggestions to sustain the development of alpine meadow ecosystem in this area. The results indicated that the aboveground net primary productivity of the ecosystem was more related to the dynamic changes of precipitation and temperature. The effect of precipitation and temperature on the net primary productivity was obvious only in present year, but not in the following years. Therefore, the alpine meadow ecosystem appears to have a higher restoration capability. By comparing the restoration capability between the alpine meadow ecosystem in study area and the four natural ecosystems in Israel and South Africa, it was found that the alpine meadow ecosystem was superior to the four natural ecosystems. To sustain the alpine meadow ecosystem, it is important to utilize the alpine grassland resources efficiently and to restore the degraded grassland timely.