Rebirth after death: forest succession dynamics in response to climate change on Gongga Mountain, Southwest China
Rebirth after death: forest succession dynamics in response to climate change on Gongga Mountain, Southwest China
复制标题
死后重生：中国西南贡嘎山应对气候变化的森林演替动态
DOI：
10.1007/s11629-017-4435-7
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发表时间：
2018-08-01
影响因子：
2.5
通讯作者：
Sun Jian
中科院分区：
文献类型：
--
作者：
Cheng Gen-wei;Lu Xu-yang;Sun Jian
全球气候变化正在对森林物种的地理分布产生长期影响。然而，山地森林垂直带对气候变化的响应仍然知之甚少。对贡嘎山森林植被垂直分布（垂直植被带）进行了30年的监测。应用GFSM数学模型对不同气候条件下垂直植被带的森林演替进行了模拟。选择了政府间气候变化专门委员会（IPCC）提出的三种可能的气候情景（B1、A1 B和A2情景分别为气温和降水增加1.8°C/5%、2.8°C/10%和3.4°C/15%）来反映全球气候的低、中、高三种变化。根据模拟结果，在B1、A1 B和A2情景下，山地植被垂直带将分别上移约300 m、500 m和600 m。因此，高山树木线将移动到更高的海拔。模拟还表明，在气候变化中，植被群落的转变将是一个缓慢而漫长的过程，其特点是两个主要阶段。在初期阶段，由于无法适应较温暖的气候，森林社区的树木退化或死亡。这导致了适宜于机会树种引入的环境条件不佳，随着演替的成功和气候变化的推进，新优势树种的植被在死亡树木腾出的空间中占据优势地位，而以前占优势的原始树木则被牺牲。因此，全球气候变化将极大地改变山区的森林群落和树种，因为新的森林群落只能通过原始树木的死亡才能生长。结果表明，气候变化将引起贡嘎山森林群落分布和组成的变化，这种变化随着气候变化强度的增加而增强。死亡与重生的交替最终会导致强烈的景观变化，并可能对山区生态环境产生强烈的影响。
Global climate change is having long-term impacts on the geographic distribution of forest species. However, the response of vertical belts of mountain forests to climate change is still little known. The vertical distribution of forest vegetation (vertical vegetation belt) on Gongga Mountain in Southwest China has been monitored for 30 years. The forest alternation of the vertical vegetation belt under different climate conditions was simulated by using a mathematical model GFSM (the Gongga Forest Succession Model). Three possible Intergovernmental Panel on Climate Change (IPCC) climate scenarios (increase of air temperature and precipitation by 1.8°C/5%, 2.8°C/10% and 3.4°C/15% for B1, A1B and A2 scenarios, respectively) were chosen to reflect lower, medium and higher changes of global climate. The vertical belts of mountainous vegetation will shift upward by approximately 300 m, 500 m and 600 m in the B1, A1B and A2 scenarios, respectively, according to the simulated results. Thus, the alpine tree-line will move to a higher altitude. The simulation also demonstrated that, in a changing climate, the shift in the vegetation community will be a slow and extended process characterized by two main phases. During the initial phase, trees of the forest community degrade or die, owing to an inability to adapt to a warmer climate. This results in modest environment for the introduction of opportunistic species, consequently, the vegetation with new dominant tree species becomes predominant in the space vacated by the dead trees at the expense of previously dominated original trees as the succession succeed and climate change advance. Hence, the global climate change would dramatically change forest communities and tree species in mountainous regions because that the new forest community can grow only through the death of the original tree. Results indicated that climate change will cause the change of distribution and composition of forest communities on Gongga Mountain, and this change may enhance as the intensity of climate change increases. As a result, the alternation of death and rebirth would finally result in intensive landscape changes, and may strongly affect the eco-environment of mountainous regions.