CO₂上昇と温暖化が水田土壌のリン利用可能性を制限（Rising CO₂ and Warming Jointly Limit Phosphorus Availability in Rice Soils）

2026-02-11 中国科学院(CAS)

Free-Air CO₂ Enrichment (Image by Prof. ZHU Chunwu’s team)

＜関連情報＞

• https://english.cas.cn/newsroom/research_news/earth/202602/t20260205_1149840.shtml
• https://www.nature.com/articles/s41561-026-01917-2
• https://www.nature.com/articles/s41561-022-01105-y

CO2増加による温暖化により、水田におけるリンの生物学的利用能の低下が深刻化 Reduced phosphorus bioavailability in rice paddies intensified by elevated CO2-driven warming

Yu Wang,Hao Chen,Weihua Su,Hongmeng Zhao,Benjamin L. Turner,Chuang Cai,Yiqi Luo,Josep Peñuelas,Kees Jan van Groenigen,Dongming Wang,Yuanyuan Huang,Mingkai Jiang,Lei Wang,Shenqiang Wang,Yong-Guan Zhu,Renfang Shen,Jiabao Zhang & Chunwu Zhu
Nature Geoscience  Published:03 February 2026
DOI:https://doi.org/10.1038/s41561-026-01917-2

Abstract

Rising atmospheric CO₂ reduces soil phosphorus (P) availability in paddy soils by promoting soil organic P accumulation and crop harvest removal. Atmospheric CO₂ and temperatures are increasing simultaneously, yet their interaction with the soil P cycle remains unresolved. Here we report a decade-long free-air CO₂ enrichment experiment integrated with in situ warming (+2 °C) in a typical paddy–upland rotation system. We find that both elevated CO₂ and warming exacerbate P constraints, and that warming alone and in combination with elevated CO₂ has a greater impact than elevated CO₂ alone. All climate change treatments significantly depleted soil available P (32–54%) and increased the soil C:P ratios (4–30%). Moreover, warming initially accelerated P mineralization but reduced P availability by enhancing Fe–organic carbon complexes and microbial immobilization. These processes, together with increased crop P demand driven by accelerated growth under elevated CO₂, exacerbate P depletion. We identify Fe–organic carbon interactions as a previously overlooked mechanism that significantly reduces P bioavailability. Our findings offer a mechanistic framework linking aboveground–belowground C–P coupling with microbially driven Fe–organic matter dynamics, highlighting the urgent need for adaptive nutrient management strategies to sustain rice production under future climate change.

大気中のCO2濃度増加による水田土壌のリン利用可能性の低下 Reduced phosphorus availability in paddy soils under atmospheric CO2 enrichment

Yu Wang,Yuanyuan Huang,Lian Song,Jiahui Yuan,Wei Li,Yongguan Zhu,Scott X. Chang,Yiqi Luo,Philippe Ciais,Josep Peñuelas,Julie Wolf,Barbara J. Cade-Menun,Shuijin Hu,Lei Wang,Dengjun Wang,Zengwei Yuan,Yujun Wang,Jishuang Zhang,Ye Tao,Shenqiang Wang,Gang Liu,Xiaoyuan Yan & Chunwu Zhu
Nature Geoscience  Published:19 January 2023
DOI:https://doi.org/10.1038/s41561-022-01105-y

Abstract

Phosphorus is an essential element for plant metabolism and growth, but its future supply under elevated levels of atmospheric CO₂ remains uncertain. Here we present measurements of phosphorus concentration from two long-term (15 and 9 years) rice free air carbon dioxide enrichment experiments. Although no changes were observed in the initial year of the experiments, by the end of the experiments soil available phosphorus had declined by more than 20% (26.9% and 21.0% for 15 and 9 years, respectively). We suggest that the reduction can be explained by the production of soil organic phosphorus that is not in a readily plant-available form, as well as by increased removal through crop harvest. Our findings further suggest that increased transfers of plant available phosphorus from biological, biochemical and chemical phosphorus under anthropogenic changes are insufficient to compensate for reductions to plant available phosphorus under long-term exposure to elevated CO₂. We estimate that reductions to rice yields could be particularly acute in low-income countries under future CO₂ scenarios without the input of additional phosphorus fertilizers to compensate, despite the potentially reduced global risk for phosphorus pollution.