Physiological and Growth Responses to Increasing Drought of an Endangered Tree Species in Southwest China

作者：Wuji Zheng, Xiaohua Gou, Jiajia Su, Haowen Fan, Ailing Yu, Wenhuo Liu, Yang Deng, Rubén D. Manzanedo, Patrick Fonti · 发表于：Forests · 年份：2019 · DOI：10.3390/f10060514 · 被引用次数：18 · 研究领域：Plant Water Relations and Carbon Dynamics、Tree-ring climate responses、Plant responses to elevated CO2

Research Highlights: We compared annually resolved records of tree-ring width and stable isotope of dead and surviving Fokienia hodginsii (Dunn) Henry et Thomas trees. We provide new insights into the relationships and sensitivity of tree growth to past and current climate, and explored the underlying mechanism of drought-induced mortality in F. hodginsii. Background and Objectives: Drought-induced tree decline and mortality are increasing in many regions around the world. Despite the high number of studies that have explored drought-induced decline, species-specific responses to drought still makes it difficult to apply general responses to specific species. The endangered conifer species, Fokienia hodginsii, has experienced multiple drought-induced mortality events in recent years. Our objective was to investigate the historical and current responses to drought of this species. Materials and Methods: We used annually resolved ring-width and δ13C chronologies to investigate tree growth and stand physiological responses to climate change and elevated CO2 concentration (Ca) in both dead and living trees between 1960 and 2015. Leaf intercellular CO2 concentration (Ci), Ci/Ca and intrinsic water-use efficiency (iWUE) were derived from δ13C. Results: δ13C were positively correlated with mean vapor pressure deficit and PDSI from previous October to current May, while ring widths were more sensitive to climatic conditions from previous June to September. Moreover, the relationships...