光合作用到CO2的适应增加了生态系统的碳储存,这是由于叶子节省了气
Nicholas G Smith1, Qing Zhu2, Trevor F Keenan2,3
1Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA.
Global change biology
|November 2, 2024
概括
光合作用适应升高的二氧化碳减少了的需求,可能增加生态系统的碳储存. 在模型中考虑保存的叶子对于准确的未来预测至关重要.
科学领域:
- 地球系统科学 地球系统科学
- 生态生态学 生态生态学
- 生物地质化学生物地质化学
背景情况:
- 光合作用是由依赖于的酶 (如RuBisCO) 驱动的,它连接了地球上的碳和循环.
- 土壤中的可用性可以在高CO2下限制植物的生产力.
- 目前的土地表面模型缺乏植物适应高二氧化碳的表现,特别是RuBisCO和叶子的下调.
研究的目的:
- 将光合作用最佳性理论纳入能源超级地球系统模型 (ELM),以模拟植物适应高CO2的情况.
- 研究光合作用适应和再分配对土地表面碳和循环在未来高二氧化碳条件下的影响.
主要方法:
- 在ELM土地表面模型中实施了光合作用最佳性理论.
- 在RCP8.5高排放场景下模拟的陆地表面碳和过程到2100年.
- 进行了与没有将保存的叶子重新分配到其他植物部位的比较模拟.
主要成果:
- 考虑光合作用适应的模拟显示光合作用增加,但在较高的CO2下,最大RuBisCO碳氧化和需求下降.
- 重新分配保存的叶子减轻了通过减少叶子需求和增强根生长来增加吸收的植物限制.
- 通过重新分配储存的叶子,到2100年生态系统的碳储量比没有重新分配的模拟增加了50.3%.
结论:
- 光合作用对高CO2的适应导致叶子节省气.
- 这些节约的重新分配可以显著增强生态系统的碳储存.
- 土地表面模型可能会高估未来的生态系统限量,如果它们不考虑光合作用适应过程中的叶子节省.
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