Kefi Sonia, Rietkerk Max, Katul Gabriel G
Department of Environmental Sciences, Copernicus Institute, Utrecht University, Heidelberglaan 2, PO Box 80115, 3508 TC Utrecht, The Netherlands.
Theor Popul Biol. 2008 Dec;74(4):332-44. doi: 10.1016/j.tpb.2008.09.004. Epub 2008 Sep 27.
Arid ecosystems are expected to be among the ecosystems most sensitive to climate change. Here, we explore via model calculations how regular vegetation patterns, widely observed in arid ecosystems, respond to projected climatic shifts as provided by general circulation model output. In our model, the photosynthesis and respiration terms are explicitly linked to physiological attributes of the plants and are forced with the primary climatic drivers: atmospheric CO(2), air temperature, and precipitation. Under future climate scenarios, our simulations show that the system's fate depends on whether the enhancements to photosynthesis due to elevated atmospheric CO(2) outweigh the increases in respiration due to higher air temperatures and the increases in water stress due to lower rainfall. A scalar measure is proposed to quantify this balance between the changes in the three climate drivers. Our model results suggest that knowing how the three primary climate drivers are evolving may provide hints as to whether the ecosystem is approaching desertification.
干旱生态系统预计是对气候变化最为敏感的生态系统之一。在此，我们通过模型计算来探究在干旱生态系统中广泛观测到的规则植被模式如何响应由大气环流模型输出所提供的预计气候变化。在我们的模型中，光合作用和呼吸作用项与植物的生理属性明确相关，并受主要气候驱动因素的影响：大气二氧化碳、气温和降水。在未来气候情景下，我们的模拟结果表明，该系统的命运取决于因大气二氧化碳浓度升高而增强的光合作用是否超过因气温升高而增加的呼吸作用以及因降雨减少而增加的水分胁迫。我们提出了一种标量度量来量化这三种气候驱动因素变化之间的平衡。我们的模型结果表明，了解这三种主要气候驱动因素如何演变可能会为该生态系统是否正在走向荒漠化提供线索。
