Key Laboratory of Western China's Environmental Systems of the Ministry of Education, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China; Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory of Western China's Environmental Systems of the Ministry of Education, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China; Gansu Liancheng Forest Ecosystem Field Observation and Research Station, Lanzhou University, Lanzhou 730000, China.
Sci Total Environ. 2024 Nov 15;951:175739. doi: 10.1016/j.scitotenv.2024.175739. Epub 2024 Aug 23.
Regional climatic differences increase the complexity of tree radial growth responses to climate change in the monsoon marginal zones and may alter the carbon sequestration capacity of forests. In this study, we collected cores of Pinus tabulaeformis trees at nine sampling sites across different regions. We analysed the relationship between tree-ring width chronology and climatic factors at different sites using dendroecological methods. We used the tree-ring index to calculate resistance, recovery, and resilience as well as to explore the capacity of radial growth to cope with drought events. The results indicate that (1) Drought was the primary factor limiting tree growth, and tree-ring climate response patterns varied across three regions. Tree growth was sensitive to both temperature and precipitation in the eastern Qilian Mountains, while it was more sensitive to temperature in the Hassan Mountains and more sensitive to precipitation in the Helan Mountains. (2) The tree-ring climate response pattern remained unstable over time, and the relative influence of current climate on tree growth increased. (3) The ecological resilience of trees to extreme events varies across three regions, which could be attributed to regional moisture conditions and the duration of drought. In the context of the management and protection of trees in the study area in the future, more attention should be paid to the elasticity of tree growth after drought events.
区域气候差异增加了季风边缘区树木径向生长对气候变化响应的复杂性,并可能改变森林的碳固存能力。本研究在季风边缘区的 9 个不同地点收集了油松(Pinus tabulaeformis)树木的芯材。我们使用树木年代学方法分析了不同地点树木年轮宽度年表与气候因子之间的关系。我们使用树木年轮指数来计算阻力、恢复力和弹性,以及探索径向生长应对干旱事件的能力。结果表明:(1)干旱是限制树木生长的主要因素,三个地区的树木年轮气候响应模式存在差异。在祁连山东部,树木生长对温度和降水都很敏感,而在哈山则对温度更敏感,在贺兰山则对降水更敏感。(2)树木年轮气候响应模式随时间不稳定,当前气候对树木生长的相对影响增加。(3)三个地区树木对极端事件的生态弹性存在差异,这可能归因于区域水分条件和干旱持续时间的不同。在未来对研究区树木的管理和保护方面,应该更加关注干旱后树木生长的弹性。