文章基本信息

标题：Five Stages of the Alaskan Arctic Cold Season with Ecosystem Implications
其他标题：Five Stages of the Alaskan Arctic Cold Season with Ecosystem Implications
本地全文：下载
作者：Peter Q. Olsson ; Matthew Sturm ; Charles H. Racine 等
期刊名称：Arctic, Antarctic, and Alpine Research
印刷版ISSN：1523-0430
电子版ISSN：1938-4246
出版年度：2003
卷号：35
期号：1
页码：74-81
DOI：10.1657/1523-0430(2003)035[0074:FSOTAA]2.0.CO%3B2
摘要：We divide the Alaskan Arctic cold season into five stages based on transitions in climatological and thermophysical conditions in the atmosphere, snowpack, and soil active layer. Each of these stages has distinct characteristics which drive ecosystem processes. During the two autumnal stages ( Early Snow and Early Cold ) soils remain warm, unfrozen water is present, and the highest rates of cold-season soil respiration occur. The next two stages ( Deep Cold and Late Cold ) are characterized by a frozen active layer with decreasing temperature. Thaw is critical in determining the length of the growing season and the resumption of biological processes. Deep Cold and Late Cold result from a radiation deficit, show little interannual variation, and will be resistant to change under almost any reasonable climate change scenario. These are also the stages with the least amount of biological activity and have the least impact on the ecosystem. However, Early Snow, Early Cold and Thaw stages vary significantly from year to year, have more ecosystem implications, and are also the most likely to undergo significant change in timing and character as the arctic climate changes. This 5-fold subdivision is useful for framing discussions of biophysical interactions during the arctic winter and for focusing attention on critical cold-season periods.