文献类型：期刊文献

英文题名：Plant water stress index as an indicator of water status and carbon-sink capacity in Chinese cork oak plantations in northern China

作者：Liu, Linqi[1,5] Luo, Kunshui[1] Xiao, Yuexin[2] Peng, Qing[1,3] Liang, Xuan[1,3] Liu, Wei[3] Zhang, Jinsong[4] Lu, Sen[4]

第一作者：Liu, Linqi

机构：[1] Jiangxi Academy of Forestry, Jiangxi Nanchang Urban Ecosystem Research Station, Nanchang, 330013, China; [2] Changsha Comprehensive Survey Center of Natural Resources, China Geological Survey, Huangshan Observation and Research Station for Land-water Resources, Changsha, 410600, China; [3] Jiangxi Agricultural University, Nanchang, 330013, China; [4] Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China; [5] Chinese Academy of Forestry, China

年份：2025

外文期刊名：SSRN

收录：EI(收录号：20250536697)

语种：英文

外文关键词：Aerodynamics - Carbon - Carbon sequestration - Drought - Ecosystems - Electric conductance - Fluxes - Forestry - Mean square error - Plants (botany) - Soil testing - Vapor pressure

摘要：The Chinese cork oak (Quercus variabilis) plantations in northern China supply critical timber, but daily tracking of their water status and drought-induced carbon-sink limitation remains difficult. We hypothesized that the plant water stress index (PWSIdT) calculated from the temperature difference between canopy and air could effectively indicate plantation water status and the impact of water availability on canopy conductance (gc) and gross primary productivity (GPP). For hypothesis testing, the canopy temperature, ecosystem fluxes, and meteorological elements in a Chinese cork oak plantation were measured in 2020 and 2021. Actual ecosystem water status was normalized by measured evapotranspiration against its potential rate (PWSIET). Compared with the minimum canopy resistance parameter, aerodynamic resistance parameters had a more substantial influence on PWSIdT performance, especially under the low vapor pressure deficit (high humidity) at our site. In aerodynamic resistance calculation, the influence of reference height should be considered. When the reference height was set high and the resistance difference between momentum and heat transfer was not considered, the PWSIdT obtained from the aerodynamic resistance parameters could accurately describe the water status of plantation ecosystems. The determination coefficient, agreement index, root mean square error, and mean error between PWSIdT and PWSIET were 0.77, 0.93, 0.09, and ?0.01±0.09, respectively. When the reference height was set close to the canopy height, the residual resistance must be incorporated into the aerodynamic resistance calculation. Moreover, drought events had serious negative impacts on the carbon sink capacity of plantation ecosystems. PWSIdT explained approximately 64% variation in gc and 70% variation in GPP of the plantation, which were larger than those explained by the soil water content index and vapor pressure deficit index. Therefore, PWSIdT provided a non-destructive, automated, and accurate way to monitor plantation water status and its consequences for ecosystem carbon sequestration. ? 2025, The Authors. All rights reserved.