文献类型：期刊文献

英文题名：Plant hydraulics provide guidance for irrigation management in mature polar plantation

作者：Guo, Youzheng[1] Ma, Yingjun[2] Ding, Changjun[3] Di, Nan[4] Liu, Yang[1] Tan, Jianbiao[1] Zhang, Shusen[1] Yu, Weichen[1] Gao, Guixi[5] Duan, Jie[1] Xi, Benye[1] Li, Ximeng[2]

第一作者：Guo, Youzheng

通信作者：Xi, BY[1];Li, XM[2]

机构：[1]Beijing Forestry Univ, Minist Educ, Key Lab Silviculture & Conservat, Beijing 100107, Peoples R China;[2]Minzu Univ China, Coll Life & Environm Sci, 27 Zhongguancun South Ave, Beijing 100081, Peoples R China;[3]Chinese Acad Forestry, Res Inst Forestry, Key Lab Tree Breeding & Cultivat State Forestry Ad, Beijing, Peoples R China;[4]Inner Mongolia Univ, Sch Ecol & Environm, Hohhot 010021, Peoples R China;[5]Bur Nat Resources & Planning, Liaocheng Forestry Dev Ctr, Liaocheng 252000, Peoples R China

年份：2023

卷号：275

外文期刊名：AGRICULTURAL WATER MANAGEMENT

收录：;EI(收录号：20224613116179);Scopus(收录号：2-s2.0-85141795181);WOS:【SCI-EXPANDED(收录号:WOS:000886234300001)】；

基金：Acknowledgements This research was supported by the National Key Research and Development Program of China (Grant No. 2021YFD2201203) and the National Natural Science Foundation (32171763, 31872702) . Ximeng Li receives funds from Young Teachers Scientific Research Ability Improvement Program of Minzu University of China (2022QNPY63) . We acknowledge Beijing Sinton Technology for providing devices and technique support.

语种：英文

外文关键词：Plantation forest; Water regulation strategy; Hydraulics; Populus; Irrigation management

摘要：Irrigation is essential for sustaining the productivity of plantation forests in arid, semi-arid, and seasonal drought regions. Current irrigation management is commonly scheduled based on time or soil water status, which often fails to capture plant physiological demand. Here we report on the variation of traits related to plant water use for 7-year-old Populus tomentosa plantations under different irrigation treatments in North China during two growth seasons with contrasting environmental dryness. Plant hydraulics were assessed by stomatal regulation strategy as well as hydraulic traits conferring water transport efficiency and safety, including branch hydraulic conductivity (Ks), thresholds for xylem embolism (Px) and percentage loss of leaf rehydration capacity (PLRC), leaf water potential at turgor loss point (psi tlp) as well as hydraulic capacitance before and after turgor loss (Cbulk-pre and Cbulk-post respectively). Our results showed that both seasonal increases in rainfall and irrigation could modify stomatal regulation strategy, resulting in a more anisohydric stomatal behavior, but through different underlying mechanisms. Specifically, seasonal variation in stomatal regulation was primarily manipulated by the daily fluctuation of leaf water potential, psi tlp, and possibly the water supply-demand relationship. At the same time, we speculated that irrigation-dependent alternation was presumably associated with shifted belowground traits. Seasonal variation in hydraulic traits was found for Ks and psi tlp, with trees in the dry season displaying higher Ks and less negative psi tlp regardless of irrigation, while other traits governing hydraulic functioning were essentially invariable across seasons or irrigation treatments. Tree growth rate was lower in the wet season and was independent of irrigation, which was likely explained by the occurrence of hydraulic impairment due to less stringent stomatal control. Overall, our results suggest that limited precipitation and high atmospheric vapor pressure deficit in the dry season would not compromise tree growth because of the tighter stomatal control, while hydraulic dysfunction could occur in the wet season due to excessive water use strategy, subsequently perhaps contributing to the reduction in growth rate. The findings of this study underscore the usefulness of physiological traits in guiding irrigation management and advocate reconsidering plantation water management strategy based on reliable indicators.