《生命科学》 2012, 24(5): 492-500
摘 要:摘 要:由于自然因素及人类活动的长期影响,全球气候变化已经成为不容置疑的事实,并对陆地生态系统的植被及土壤产生了深远影响。陆地植被- 土壤生态系统在全球气候变化中的反应与适应等过程已成为众多科学家所关注的问题。为更好地了解陆地植被- 土壤生态系统对全球气候变化的响应机制,综述了气候变暖对植物的物候与生长、光合特征、生物量生产与分配,以及土壤呼吸等方面的影响,并对分析得到的结论进行了总结。分析指出,随着全球气候变暖,植物个体和群落特征以及土壤特性都会发生相应改变,高海拔地区的植被高度有增加趋势,而低海拔地区的植被可能出现矮化。然而,在以下方面还存有不确定性:(1) 气候变暖导致的植被特征变化是否会减弱全球气候变化;(2) 在较长时间尺度上气候变暖如何影响植物的物候和生长,特别是植物的体型;(3) 高寒生态系统冬季土壤呼吸对气候变暖如何响应。
关键词:气候变暖;物候;光合;生物量;土壤呼吸
Abstract: Abstract: Global climate change, particularly the climate warming has become a credible fact owing to the longterm effects of natural factors and human activities, such as the increasing contents of atmospheric carbon dioxide and other greenhouse gases. Plants and soil are significant components of terrestrial ecosystem and play an important role, which are affected deeply by the global climate change. It is generally believed that the responses of ecosystem to elevated temperature are sensitive and swift in high-latitude and high-elevation regions, especially in the Qinghai-Tibetan Plateau, which has been considered as an ideal place to study the response mechanism of terrestrial ecosystem to the global climate change. Some relevant studies have revealed that the activities of grassland vegetation are enhanced in Qinghai-Tibet Plateau and the activities of grassland vegetation is closely related to the global climate change, especially the elevated temperature. Therefore, it has become a hot point to study the response and adaptation of terrestrial plant-soil ecosystem under the condition of global climate change. In order to better understand the response mechanism of terrestrial plant-soil ecosystem to the global climate change, the effects of climate warming on plant features were reviewed, such as plant phenology and growth, plant photosynthetic characteristics, plant biomass production and allocation, together with soil characteristics, for example the soil respiration. At the same time, the results were analyzed and the conclusions were summarized, which indicated that the features of plant individual and community varied with global climate warming as well as the characteristics of soil. In high-elevation region, vegetation presented a trend of increase in height. However, it might appear dwarf in low-elevation region. Though extensive studies had been conducted in various ecosystems, several uncertainties still remained. First of all, could varieties of plant features induced by climate warming offset the global warming? Secondly, how did climate warming affect plant phenology and growth, especially the size of plants in future decades or in even longer time scale? Thirdly, how did soil respiration of alpine ecosystem response to climate warming? These uncertainties needed to be studied further in the future.
Key words: climate warming; phenology; photosynthesis; biomass; soil respiration