长期湿度变化比CO2在确定热带木质植被变化的作用更大
William D Gosling1, Charlotte S Miller2, Timothy M Shanahan3
1Institute for Biodiversity & Ecosystem Dynamics, University of Amsterdam, Netherlands.
Science (New York, N.Y.)
|May 5, 2022
概括
增加的二氧化碳 (CO2) 可能不会显著增加热带木质覆盖. 过去的环境数据显示湿度和火灾活动是主要的驱动因素,而不是二氧化碳,这表明需要修改气候模型.
科学领域:
- 古气候学
- 生态学
- 地球系统科学
背景情况:
- 假设二氧化碳 (eCO2) 的增加可以促进热带生态系统中的木质植物生长.
- 目前的地球系统模型包含了这种eCO2受精效应.
- 这种关系的长期经验验证是具有挑战性的.
研究的目的:
- 研究过去50万年多种环境驱动因素对热带木质覆盖的相对影响.
- 评估大气中的二氧化碳与湿度,火力和温度等其他因素的作用.
- 对地球系统模型关于热带植被反应的准确性提供信息.
主要方法:
- 分析了来自加纳Bosumtwi湖的古环境数据与全球气候记录.
- 重建过去的植物动态和环境条件超过50万年.
- 六个关键因素的重要性的统计评估:湿度,火灾,食草动物,温度,温度季节性和CO2.
主要成果:
- 湿度和火灾活动被确定为控制木质覆盖的主要因素.
- 发现二氧化碳 (CO2) 增加对木质覆盖的影响很小.
- 这项研究提供了长期的经验数据,质疑二氧化碳受精的意义.
结论:
- 过去的热带木质覆盖主要由湿度和火灾调节,而不是大气中的二氧化碳水平.
- 人为增加的二氧化碳对热带植被的影响可能在当前的预测模型中被高估.
- 为了改善气候变化预测,需要重新评估二氧化碳在热带生态系统动态中的作用.
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