2025-10-13 中国科学院（CAS）
＜関連情報＞
- https://english.cas.cn/newsroom/research_news/earth/202510/t20251013_1089355.shtml
- https://www.nature.com/articles/s41561-025-01816-y
温暖化による植物の窒素同化に必要な炭素コストの増加 Increased carbon cost for nitrogen assimilation in plants under a warming climate
Chao-Chen Hu,Chen-Guang Tian,Chong-Juan Chen,Wei Song,Xu Yue & Xue-Yan Liu
Nature Geoscience Published:06 October 2025
DOI:https://doi.org/10.1038/s41561-025-01816-y
Abstract
Nitrogen (N) assimilation consumes carbon (C) in plants, and climate warming can alter soil N availability, thereby affecting plant N assimilation and associated C costs. However, the global C cost of N assimilation in terrestrial plants has long been unconstrained, and its warming response remains uncertain. Here we constructed a modelling framework of plant C costs for nitrate, ammonium and extractable organic N assimilation and assessed global C costs of plant N assimilation. Globally, the C costs for plant N assimilation were 208 ± 12 and 249 ± 15 TgC yr−1 under the present-day and 2.0 °C warming scenarios, respectively, which exceed the C emissions caused by deforestation and degradation fires and are comparable to the forest C fixed by atmospheric N deposition. Under the warming scenario, the global C cost would increase by 47% (41 ± 19 TgC yr−1), with a greater percentage increase at higher latitudes, due partly to enhanced contributions and C cost of soil inorganic N. We conclude that the C cost for N assimilation in terrestrial plants should be incorporated into global C budgets, while its positive response to warming would improve predictions of terrestrial C-cycle feedbacks to global warming.
