中国不同气候带植被挥发性有机化合物通量与生态系统演替的相关性

The Correlation Between the Volatile Organic Compound Emissions and the Vegetation Succession of the Ecosystems in Different Climatic Zones of China

从群落水平和生态系统演替的角度对中国热带、亚热带和温带生态系统植物挥发性有机化合物 (VOC)通量的研究表明 ,异戊二烯通量呈现出在生态系统演替的早期到中期阶段随着演替的进行而升高 ,在先锋性灌木和乔木阶段达到高峰 ,然后又随着演替的发展而逐渐下降的演替格局 ,而其他VOC通量则有随着演替的进行而上升的趋势。生态系统不同演替阶段异戊二烯通量的变化可能与植物获取养分氮有关 ;根据植物VOC释放通量的生态演替格局 ,可以建立全球陆地生态系统的VOC模型 ,对大气化学过程中的VOC时空动态进行很好的模拟。

Isoprene and stored volatile organic compound (VOC) emissions along the succession of ecosystem in tropical, subtropical and temper-ate areas were characterized using a portable hydrocarbon detector and GCMS-AED analysis. Isoprene emissions were observed to exhibit an ecological pattern whereby emissions were highest in early to middle successional (developmental) woodland and forest communities, and relatively low in late successional forest and peatland communities. This pattern may result from the ability of isoprene to enhance the availability of nitrogen that is deposited in the strongly nitrogen limited ecosystems. These findings from China along with the similar findings from North America, Puerto Rico, central Amazon, and central Africa point to characteristic growth form structure and VOC chemistry that ecosystems may share globally. This successional pattern would be useful in building a simple ecosystem-based, instead of painstaking species-based, model of VOC emission.