大气中的二氧化碳会导致当地突然的植被变化,但不是全球性的
Steven I Higgins1, Simon Scheiter
1Institut für Physische Geographie, Goethe Universität Frankfurt am Main, 60438 Frankfurt am Main, Germany. higgins@em.uni-frankfurt.de
Nature
|July 6, 2012
概括
人为气候变化可能会将地球系统推向新的状态. 热带生态系统可能会由于二氧化碳水平的上升而转向更高的生物质或木质状态.
科学领域:
- 地球系统科学 地球系统科学
- 气候变化生物学 气候变化生物学
- 生态生态学 生态生态学
背景情况:
- 地球系统科学家们担心倾斜元素,这是大规模的组件,可以突然改变状态.
- 大规模植被系统表现出倾斜行为的潜力尚未得到充分理解.
- 热带草原,大草原和森林生态系统是地球系统的重要组成部分.
研究的目的:
- 调查热带植被系统是否可能转移到替代状态.
- 为了确定增加大气二氧化碳对植被状态的影响.
- 分析影响植被模式变化的时间和位置的因素.
主要方法:
- 对气候变化情景的植被反应的建模.
- 分析热带草原,大草原和森林生态系统的临界点.
- 评估二氧化碳度,温度增加,火灾严重程度和降雨变化的影响.
主要成果:
- 热带草原,大草原和森林生态系统可能会转移到替代状态.
- 大气中二氧化碳度的增加将推动向生物质较高和/或木质植物占主导地位的状态过渡.
- 这些变化的时间取决于温度上升的速度,火灾的严重程度和降雨量,两位稳定的植被区将迁移.
结论:
- 由于气候变化,陆地生态系统可能会发生大规模的定向制度转变.
- 不同地区的异步转移可能会减轻,但不能消除对地球系统的整体影响.
- 了解这些植被转折点对于预测未来地球系统状态至关重要.
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