文献类型：期刊文献

英文题名：The Afternoon/Morning Ratio of Tower-Based Solar-Induced Chlorophyll Fluorescence Can Be Used to Monitor Drought in a Chinese Cork Oak Plantation

作者：Pan, Qingmei[1,2,3] Cheng, Xiangfen[1,2,3] Hu, Meijun[1,2,3] Liu, Linqi[3,4] Wang, Xin[1,2,3] Zhang, Jinsong[1,2,3] Li, Zhipeng[1,2,3] Yuan, Wenwen[3,5] Gao, Xiang[1,2,3]

第一作者：Pan, Qingmei

通信作者：Zhang, JS[1];Zhang, JS[2];Zhang, JS[3]

机构：[1]Chinese Acad Forestry, Res Inst Forestry, Key Lab Tree Breeding & Cultivat State Forestry Ad, Beijing 100091, Peoples R China;[2]Nanjing Forestry Univ, Collaborat Innovat Ctr Sustainable Forestry Southe, Nanjing 210037, Peoples R China;[3]Henan Xiaolangdi Forest Ecosyst Natl Observat & Re, Jiyuan 454650, Peoples R China;[4]Jiangxi Acad Forestry, Nanchang 330013, Peoples R China;[5]Chinese Acad Forestry, Res Inst Subtrop Forestry, Hangzhou 311400, Peoples R China

年份：2024

卷号：16

期号：11

外文期刊名：REMOTE SENSING

收录：;EI(收录号：20242516263000);Scopus(收录号：2-s2.0-85195879920);WOS:【SCI-EXPANDED(收录号:WOS:001245690800001)】；

基金：We thank Chunxia He and Yu Zhou from the Chinese Academy of Forestry for contributing to field measurements and data analysis. We thank Chaoyue Wu, Yongbin Huang, and Ning Zheng for helping to run the spectrometer systems and eddy covariance systems.

语种：英文

外文关键词：sun-induced chlorophyll fluorescence (SIF); drought; afternoon depression; afternoon/morning ratio (AMR); plantation

摘要：Monitoring drought stress is crucial for estimating productivity and assessing the health status of forest ecosystems under global climate change. Solar-induced chlorophyll fluorescence (SIF) is mechanistically coupled to photosynthesis and has advantages over greenness-based vegetation indices in detecting drought. In recent years, SIF has commonly been used in monitoring drought stress in crop ecosystems. However, the response of tower-based SIF to drought stress in forest ecosystems remains unclear. In this study, we investigated the potential of tower-based SIF to monitor drought, which was quantified using the plant water stress index (PWSI) in a Chinese cork oak plantation. The results show the negative effect of drought on SIF, and afternoon depression of SIF emission under drought stress was observed. Canopy SIF (F) exhibited a nonlinear relationship with PWSI, while the quantum yield of SIF (Phi F) exhibited a significant linear relationship with PWSI at 687 nm and 760 nm (Phi F687: R2 = 0.90; Phi F760: R2 = 0.85). Incident radiation (PAR) and canopy structure affected the response of SIF to drought stress, with PAR as the main factor causing the nonlinear relationship between F and PWSI. Afternoon depression was described as the afternoon/morning ratio (AMR). AMRF and AMR Phi F exhibited a negative linear response to PWSI. AMRF was less affected than F by PAR and canopy structures, and AMR Phi F was more physiologically representative than Phi F. Moreover, AMR Phi F was sensitive to VPD and REW, and it might be a good indicator of drought. Red SIF was more sensitive to drought than far-red SIF, as the R2 of PWSI with AMR Phi F687 (R2 = 0.89) was higher than that with AMR Phi F687 (R2 = 0.84). These results highlight the potential of tower-based SIF, especially red SIF, for drought monitoring in a plantation, and consideration of the physiological diurnal variation in SIF under drought stress is crucial for improving the accuracy of drought stress monitoring.