In Europe, it is undoubtedly the mountainecosystem which has changed most rapidly and is most at risk.
在欧洲，变化最快、风险最大的无疑是山地生态系统。
2
In this paper, the general situation of mountainecosystem was briefly introduced and the effects of keystone populations on the degraded ecosystem were discussed.
简要介绍了岷江上游山地生态系统的概况，讨论了关键种群在退化生态系统研究中的作用和意义。
3
But as global warming snakes its way into higher altitudes, a less-welcome resident in taking up space in this fragile ecosystem: the mountain pine beetle.