高山灌草交错带植被对不同时段模拟增温的响应机理

Due to its particular geographical position and special vegetation succession, the alpine scrub-meadow ecotone is one of the most sensitive areas to global change, and is also an ideal place for studying the responses of terrestiral ecosystems to global climate change. However，there is a lack of knowledge on the responses of alpine ecotones to non-growing season climate change. Hence, we select the alpine scrub-meadow ecotone vegetation on the east slop of Gongga Mountain as the study object, by adopting the method of simulated warming, to study the responses in nutrient use efficiency, water use efficiency, reproductive investment, phonological phenomenon, population density and coverage to different simulated warming durations(growing season, non-growing season and all year round), to compare the similarities and differences between the effects of growing season warming and non-growing season warming, and to analyze the contribution of growing season warming and non-growing season warming to the effects of all year round warming. The result of this study would not only deepen the knowledge on non-growing season warming effects, further revealing the biological response mechanism of terrestrial ecosystems to global climate change, but it is also important for predicting the influence of future climate change on alpine ecosystems, and, for drafting and adopting proper measures to cope with climate change.

高山植物群落交错带是陆地生态系统对全球变化响应的敏感指示器。针对目前缺乏非生长季气候变暖对植物影响的系统研究，本项目拟以贡嘎山东坡高山灌草交错带植被为研究对象，采用开顶式生长室模拟增温的方法，进行不同时间段的模拟增温试验（非生长季增温、生长季增温、全年增温），从植物个体的养分与水分利用效率、抗逆性、生殖投入、物候及种群密度与盖度等方面比较非生长季增温与生长季增温效应的异同，分析非生长季增温与生长季增温对全年增温效应的影响大小，全面揭示高山灌草交错带植被对不同时段模拟增温的响应机理。本研究结果不但有助于加深人们对非生长季气候变暖效应的认识，进一步揭示植物对全球变暖的生物学响应机制，而且对预测未来气候变化对高山生态系统可能造成的影响、制定并采取恰当的应对措施具有重要意义。