The responses of dominant tree species to climate warming at the treeline on the eastern edge of the Tibetan Plateau
The responses of dominant tree species to climate warming at the treeline on the eastern edge of the Tibetan Plateau
复制标题
青藏高原东缘林线优势树种对气候变暖的响应
DOI：
10.1016/j.foreco.2018.05.021
复制
发表时间：
2018-10-01
影响因子：
3.7
通讯作者：
Liu, Shirong
中科院分区：
文献类型：
--
作者：
Guo, Mingming;Zhang, Yuandong;Liu, Shirong
树木生长在北方/高山树木线一般预计将刺激气候变暖。然而，在许多研究中，树木的生长变化不大或减少。树木对气候变暖的反应在同一生态区的不同物种之间也有所不同。青藏高原在过去几十年中经历了快速变暖。目前还不清楚该地区的主要物种如何应对这种变暖，预计这将显着影响树线动态。在青藏高原东缘6个林线样点采集288个冷杉（冷杉和鳞叶冷杉）和云杉（紫云杉和白云杉）树芯，研究其生长动态和气候响应。结果表明，杉木的生长在任何地点都没有明显变化，而云杉的生长增加，特别是在松潘和炉霍网站。4月对冷杉生长的强烈负温度或正水分控制表明春季干旱胁迫。云杉径向生长与6、7月气温呈显著正相关;松潘和炉霍样地云杉径向生长与2 ~ 4月气温也呈显著正相关。结果表明，生长季前温度和生长季温度均促进云杉的生长，而生长季前温度对冷杉造成干旱胁迫。随着气候变暖的持续，青藏高原东部边缘高山树线的树种组成将发生变化。
Tree growth at boreal/alpine treelines is generally expected to be stimulated by climate warming. However, tree growth has been shown to have changed insignificantly or reduced in numerous studies. Tree response to climate warming also varies among species in the same eco-region. The Tibetan Plateau has experienced rapid warming in the past several decades. It remains unknown how the dominant species in this region have responded to this warming, which is expected to significantly influence treeline dynamics. We obtained 288 tree cores from fir (Abies faxoniana and Abies squamata) and spruce (Picea purpurea and Picea baifouriarta) at six treeline sites on the eastern edge of the Tibetan Plateau to detect their growth trends and climate responses. The results showed that the growth of fir did not change significantly at any site, whereas spruce growth increased, especially at the Songpan and Luhuo sites. The strong negative temperature or positive moisture controls of April on fir growth indicated spring drought stress. The radial growth of spruce was positively related to June and July temperature; at the Songpan and Luhuo sites, it was also positively related to the temperature from February to April. The results indicate that both pre-growing season temperature and growing season temperature accelerate spruce growth, whereas pre-growing season temperature causes drought stress to fir. The tree species composition at the alpine treeline on the eastern edge of the Tibetan Plateau will change as warming continues.