Sensitivity of gross primary production and evapotranspiration to heat and drought stress in a young temperate plantation in northern China

作者：Hongxian Zhao, Zeyuan Zhou, Feng Zhang, Charles P.‐A. Bourque, Xin Jia, Xinhao Li, Peng Liu, Haiqun Yu, Yun Tian, Chuan Jin, Shaorong Hao, Tianshan Zha · 发表于：Forest Ecosystems · 年份：2024 · DOI：10.1016/j.fecs.2024.100275 · 被引用次数：12 · 研究领域：Plant Water Relations and Carbon Dynamics、Tree-ring climate responses、Greenhouse Technology and Climate Control

Assessing the sensitivities of ecosystem functions to climatic factors is essential to understanding the response of ecosystems to environmental change. Temperate plantation forests contribute to global greening and climate change mitigation, yet little is known as to the sensitivity of gross primary production (GPP) and evapotranspiration (ET) of these forests to heat and drought stress. Based on near-continuous, eddy-covariance and hydrometeorological data from a young temperate plantation forest in Beijing, China (2012–2019), we used a sliding-window-fitting technique to assess the seasonal and interannual variation in ecosystem sensitivity (i.e., calculated slopes, S GPP-Ta , S ET-Ta , S GPP-EF , and S ET-EF ) in GPP and ET to anomalies in air temperature ( T a ) and evaporative fraction (EF). The EF was used here as an indicator of drought. Seasonally, daily S GPP-Ta , S ET-Ta , and S GPP-EF were greatest in summer, reaching maxima of 1.12 ± 0.56 g C·m −2 ·d −1 ⋅°C −1 , 1.36 ± 0.56 g H 2 O·m −2 ·d −1 ⋅°C −1 , and 0.37 ± 0.35 g C·m −2 ·d −1 , respectively. Evapotranspiration was constrained by drought, especially during the spring-to-summer period, S ET-EF reaching −0.51 ± 0.34 g H 2 O·m −2 ·d −1 . Variables EF, T a , soil water content (SWC), vapor pressure deficit (VPD), and precipitation (PPT) were the main controls of sensitivity, with S GPP-Ta and S ET-Ta increasing with T a , VPD, and PPT (<50 mm·d −1 ) during both spring and autumn. Increased drought stress during ...