Abstract：
The influence of tree age on the growth response of Picea likiangensis, a predominant timber species in southwestern China, to climatic factors has been under-researched. In this study, we examined the relationships between tree age and the response of P. likiangensis to climatic factors and extreme drought events using tree-ring samples procured from the southeastern edge of the Tibetan Plateau. The results revealed differential responses of the radial growth of P. likiangensis trees of varying ages to climatic factors and extreme drought events. Specifically, deficient water availability during the early growing season emerged as the principal factor constraining radial growth across all age classes. Young and middle-aged trees (<100 years) demonstrated greater responsiveness to water availability than did mature trees (>100 years). Mature trees, in contrast, demonstrated markedly greater resistance to extreme drought events than young and middle-aged trees. Comparative studies of individual trees across different ages revealed negligible differences in the response of young and middle-aged trees to climatic factors and extreme drought events. Given these responses, future forest management practices should prioritize young and middle-aged trees that are more affected by drought to maximize the ecological value of the species. According to the specific research objectives, sample collection processes should classify mature trees and young and middle-aged trees, to minimize the influence of tree age on the final findings of the study.
摘要：
树龄对云杉生长响应的影响,中国西南部的主要木材树种，对气候因素的研究不足。在这项研究中,我们使用从青藏高原东南边缘采购的树木年轮样品，研究了树龄与假单胞菌对气候因素和极端干旱事件的响应之间的关系。结果揭示了不同年龄的假树的径向生长对气候因素和极端干旱事件的不同响应。具体来说,在早期的生长季节中，水分不足是限制所有年龄段径向生长的主要因素。年轻和中年树木（<100年）比成熟树木（>100年）表现出对水资源的更高反应。成熟的树木，相比之下,表现出对极端干旱事件的抵抗力明显高于年轻和中年树木。对不同年龄的单个树木的比较研究表明，中青年树木对气候因素和极端干旱事件的反应差异可忽略不计。鉴于这些反应,未来的森林管理实践应优先考虑受干旱影响较大的中青年树木，以最大限度地提高该物种的生态价值。根据具体的研究目标,样本收集过程应该对成熟树木和幼树和中年树木进行分类，尽量减少树龄对研究最终结果的影响。
