Variable influence of photosynthetic thermal acclimation on future carbon uptake in Australian wooded ecosystems under climate change

作者：Alison C. Bennett, Jürgen Knauer, Lauren T. Bennett, Vanessa Haverd, Stefan K. Arndt · 发表于：Global Change Biology · 年份：2023 · DOI：10.1111/gcb.17021 · 被引用次数：23 · 研究领域：Plant Water Relations and Carbon Dynamics、Plant responses to elevated CO2、Climate variability and models

Abstract Climate change will impact gross primary productivity (GPP), net primary productivity (NPP), and carbon storage in wooded ecosystems. The extent of change will be influenced by thermal acclimation of photosynthesis—the ability of plants to adjust net photosynthetic rates in response to growth temperatures—yet regional differences in acclimation effects among wooded ecosystems is currently unknown. We examined the effects of changing climate on 17 Australian wooded ecosystems with and without the effects of thermal acclimation of C3 photosynthesis. Ecosystems were drawn from five ecoregions (tropical savanna, tropical forest, Mediterranean woodlands, temperate woodlands, and temperate forests) that span Australia's climatic range. We used the CABLE‐POP land surface model adapted with thermal acclimation functions and forced with HadGEM2‐ES climate projections from RCP8.5. For each site and ecoregion we examined (a) effects of climate change on GPP, NPP, and live tree carbon storage; and (b) impacts of thermal acclimation of photosynthesis on simulated changes. Between the end of the historical (1976–2005) and projected (2070–2099) periods simulated annual carbon uptake increased in the majority of ecosystems by 26.1%–63.3% for GPP and 15%–61.5% for NPP. Thermal acclimation of photosynthesis further increased GPP and NPP in tropical savannas by 27.2% and 22.4% and by 11% and 10.1% in tropical forests with positive effects concentrated in the wet season (tropical savann...