文章基本信息

标题：Dynamic Cloud Regimes, Incident Sunlight, and Leaf Temperatures in Espeletia grandiflora and Chusquea tessellata , Two Representative Species of the Andean Páramo, Colombia
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作者：Adriana Sanchez ; Juan M. Posada ; William K. Smith 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：2014
卷号：46
期号：2
页码：371-378
DOI：10.1657/1938-4246-46.2.371
摘要：The alpine páramo of Chingaza National Park, Colombia, has a highly variable cloud regime typical of many tropical alpine areas. Yet, little information is available regarding the effects of such dynamic sunlight regimes on alpine temperatures. A close association between changes in incident sunlight and corresponding air ( T a ) and leaf ( T l ) temperatures occurred in two dominant species with strongly contrasting leaf form and whole-plant architecture. Spikes in sunlight incidence of >3000 μmol m −2 s −1 occurred during cloud cover and corresponded to increases in T l of 4–5 °C in a 1-min-interval in both species. Although T l was predominately above T a , during the day, depressions below T a of over 6 °C occurred during cloudy conditions when photosynthetic photon flux density (PFD s ) was 1000 μmol m −2 s −1 occurred for 2.4% of the day, including a maximum change of 1512 μmol m −2 s −1 . These data may be valuable for predicting the ecophysiological impact of climate warming and associated changes in future cloud regimes experienced by tropical alpine species.