揭示热带森林光合作用过程中的气候驱动因素
Yuan Wang1, Junjie Liu1,2, Paul O Wennberg1,3
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California, USA.
Global change biology
|July 4, 2023
概括
热带森林的碳吸收 (GPP) 根据地区而异,在非洲和亚马逊地区受到水的限制.
科学领域:
- 生态与地球系统科学 生态与地球系统科学
- 气候变化研究 气候变化研究
- 遥感应用 遥感应用
背景情况:
- 热带森林对于全球碳循环调节至关重要.
- 气候变化对热带森林碳动态的影响仍然不确定.
- 太阳引起的叶绿素光 (SIF) 为总初级生产 (GPP) 提供了一个代理.
研究的目的:
- 通过使用卫星SIF数据,调查热带森林GPP对气候变化的反应.
- 在热带地区识别不同的气候-GPP关系.
- 评估这些关系在当前植被模型中的表现.
主要方法:
- 使用了三年 (2018-2021) 的TROPOMI卫星SIF数据.
- 将SIF数据与气候再分析和卫星产品结合起来.
- 应用主要组件分析和相关性分析来确定GPP限制制度.
主要成果:
- 确定了两个主要的GPP限制制度:水限制 (非洲,亚马逊南部) 和能源限制 (东南亚,亚马逊北部).
- 非洲的GPP与水因素 (VPD,土壤水分) 有很强的相关性;东南亚的GPP与能源因素 (PAR,温度) 有很强的相关性.
- 观察到越来越多的SIF-VPD与各大洲平均VPD的合,以及一些跨年相关性.
结论:
- 热带森林GPP对气候的反应是异质的,具有明显的水和能源限制.
- 目前的全球动态植被模型不充分反映了干旱热带地区的GPP-VPD合.
- 预测未来的热带碳动态可能是不可靠的,因为在捕获碳水循环相互作用的模型限制.
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