Effects of Phenology, Physiology, and Gradients in Community Composition, Structure, and Microclimate on Tundra Ecosystem CO2 Exchange
Effects of Phenology, Physiology, and Gradients in Community Composition, Structure, and Microclimate on Tundra Ecosystem CO2 Exchange
复制标题
物候、生理和群落组成、结构和小气候梯度对苔原生态系统二氧化碳交换的影响
DOI：
--
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
S. Oberbauer
中科院分区：
文献类型：
--
作者：
J. Tenhunen;R. Siegwolf;S. Oberbauer
最近，科学家们的注意力集中在潜在的全球气候变化以及污染物的沉积及其影响上。这些观点强调生态系统作为大气和植被之间以及植被和地下水之间的交换面的作用(Dickenson 1988；Bolin 1988；Ulrich 1987)。特别是在泰加北部和冻原地区，重要的是要确定气候变化是否已经改变或未来可能改变生态系统碳储存的速率(正或负)(Oberbauer等人)。1992年；奥切尔和比林斯1992年)。此外，重要的是了解环境对碳通量和碳储存的控制，因为北极土壤温度、水可获得性和有效光能的梯度很大，这些都将强烈影响净二氧化碳的积分值(Tenhunen等人)。极地地区的甲烷交换(惠伦和里堡，1988年，1990年)。即使从简单的区域尺度来看，在估算碳平衡时也必须考虑生态系统物质交换特征的时间和空间变化(Miller等人。1983年)。在较小的尺度，如分水岭，生态系统结构、物种组成、生理和环境条件的时间和空间变化决定了瞬时净气体交换率，但也提供了关于未来气候中生态系统特性可能发生区域性转移的方式的线索(Chapin等人)。(1992年)。
Recently, attention among scientists has been focused on potential global climate change as well as on the deposition of pollutants and their impacts. These perspectives emphasize the role of ecosystems as exchange surfaces between atmosphere and vegetation and between vegetation and groundwater (Dickenson 1988; Bolin 1988; Ulrich 1987). Particularly with respect to northern taiga and tundra regions, it is important to determine whether climate change may have already altered or may in the future alter rates (positive or negative) of ecosystem carbon storage (Oberbauer et al. 1992; Oechel and Billings 1992). Furthermore, it is important to understand environmental controls on carbon fluxes and carbon storage, because the gradients in soil temperature, water availability, and available light energy in the Arctic are large and these will strongly affect the integrated values of net carbon dioxide (Tenhunen et al. 1992) and methane exchange (Whalen and Reeburgh 1988, 1990) in polar regions. Even when viewed simplistically and at the regional scale, temporal and spatial variation in ecosystem material exchange characteristics must be considered when estimating carbon balances (Miller et al. 1983). At smaller scales such as the watershed, temporal and spatial variation in ecosystem structure, species composition, physiology, and environmental conditions determine momentary net gas exchange rates, but also provide clues concerning the manner in which ecosystem properties may be shifted regionally in a future climate (Chapin et al. 1992).