SGER: Effects of Avalanches on Local Carbon Budgets and Regional Forest Dynamics

在北美西部科迪勒拉的许多地方和许多其他高山山脉，雪崩路径无处不在。最近有越来越多的证据表明，雪崩可能在山区生态系统的功能中发挥比以前预期的更重要的作用。由于大量植被可能从较高的斜坡被带到山谷，雪崩可能对不同地区净初级生产力的变化模式产生深远的影响，并可能显著改变高山环境下的碳和氮收支。这项探索性研究小额赠款将支持2002年夏季和初秋的初步工作，以研究雪崩在山区生态系统功能中所起的作用。研究人员将根据雪崩对碳、氮、沉积物和木质碎屑的分布和运动的影响，评估雪崩和雪崩路径对山地功能的贡献。在蒙大拿州冰川国家公园的南部工作，调查人员将进行初步的实地工作，以估计雪崩移动的碳和木质碎片的数量。这些数据以及从IKONIS卫星图像中收集的1米和4米尺度的数据将用于开发和测试碳和木质碎片的景观尺度通量模型。预计该项目的成果将包括对受雪崩影响地区的物质流动的一般规模和程度进行首次系统评估。这个项目产生的数据和见解应该形成一个基线，这些和其他调查人员可以使用它来扩大调查的一般范围，包括其他材料和其他地点。该项目预计将产生的主要成果是量化雪崩路径对碳和木材的移动和储存的潜在意义，并测试将实地数据和遥感数据结合起来将定量分析扩展到景观或区域尺度的潜力。该项目应有助于开发在尺度依赖的背景下表征景观结构、功能和变化的技术，从而为高山动态的生物地理学、地貌学和水文研究提供见解。该项目还将为扩大研究生教育和培训提供机会。

Avalanche paths are ubiquitous features in many parts of the western cordillera of North America and many other high mountain ranges. Evidence has mounted recently that avalanches may play more significant roles in the functioning of mountain ecosystems that previously had been anticipated. Because massive amounts of vegetation may be carried from higher slopes to valleys, avalanches can have profound impacts on changing patterns of net primary productivity in different locales, and they can dramatically alter carbon and nitrogen budgets within alpine settings. This Small Grant for Exploratory Research will support preliminary work during the summer and early fall of 2002 to examine the role that snow avalanches play in the functioning of mountain ecosystems. The investigators will assess the contribution of avalanches and avalanche paths to mountain functions in terms of their impacts on the distribution and movements of carbon, nitrogen, sediments, and woody debris. Working in the southern part of Glacier National Park in Montana, the investigators will conduct preliminary field work to estimate the amounts of carbon and woody debris moved by snow avalanches. These data and data collected from IKONIS satellite imagery at 1-meter and 4-meter scales will be used to develop and test landscape-scale flux models for carbon and woody debris. The results of this project are expected to include the first systematic assessment of the general scale and magnitude of material flux in areas affected by avalanches.The data and insights produced by this project should form a baseline that these and other investigators can use to broader the general scope of inquiry to include other materials and other locations. Major outcomes of the project expected to result from this project are a quantification of the potential significance of avalanche paths to the movement and storage of carbon and wood and a test of the potential to combine field-based and remotely sensed data to extend quantitative analyses to landscape or regional scales. The project should help develop techniques to characterize landscape structure, function, and change within a scale-dependent context that offers insights into biogeographic, geomorphic, and hydrologic studies of alpine dynamics. The project also will provide opportunities for expanded graduate student education and training.