Climatic Variation and Disturbance Interactions in Subalpine Rocky Mountain Forests

亚高山落基山脉森林的气候变化和干扰相互作用科罗拉多大学博尔德分校Veblen，Thomas T.气候变化预计将通过影响火灾和昆虫爆发的频率，加剧对森林景观的干扰。该项目将解决以下问题：需要更好地了解这类干扰的时空性质、气候变化对森林动态的作用以及这些景观遗产在改变森林对未来干扰的敏感性方面的重要性。具体地说，这项工作将研究落基山脉南部森林生态系统中森林干扰如何与广泛的环境梯度相关。这项研究要解决的关键问题包括：什么气候条件有利于在地形和广泛的气候梯度上发生火灾和致命的昆虫；地形的多变性如何影响火灾和昆虫发生后森林恢复的性质和速度以及今后对干扰的敏感性；以及以往火灾和昆虫的重大干扰造成的景观遗产如何影响随后的干扰的频率、蔓延和严重程度？该项目将为森林景观中的干扰过程如何应对空间不同环境中的气候变化贡献新的知识。在方法上，这项研究将把对干扰和气候变化的详细树轮分析与对过去干扰事件与地形环境相关的空间相互作用的地理信息系统分析结合起来。这种多尺度的经验分析将阐明细尺度约束与粗尺度约束对扰动过程的相对作用。该项目的结果将对科罗拉多州国家公园和国家森林的森林资源规划和管理具有重要意义。特别是，在规划未来干扰事件的蔓延和严重程度时，需要考虑到先前火灾和虫害暴发造成的干扰在景观中留下的遗产。

Climatic Variation and Disturbance Interactions in Subalpine Rocky Mountain ForestsVeblen, Thomas T.University of Colorado at BoulderClimate change is expected to exacerbate disturbances to forested landscape through impacts on frequency of fire and insect outbreaks. This project will address the need for an improved understanding of the spatial and temporal nature of such disturbances, the role of climate variability on forest dynamics, and the significance of these landscape legacies in altering forest susceptibility to future disturbance. Specifically, this work will examine how forest disturbances vary in relation to broad environmental gradients in southern Rocky Mountain forest ecosystems. Key questions to be addressed in this research include: what climatic conditions are conducive to fire and lethal insect outbreaks across topographic and broad climatic gradients; how does topographic variability affect the nature and rate of forest recovery following fire and insect outbreaks and future susceptibility to disturbance; and how do landscape legacies resulting from major previous disturbance by fire and insect outbreaks affect the subsequent frequency, spread and severity of disturbances? This project will contribute new knowledge to how disturbance processes in forested landscapes respond to climatic variation in spatially heterogeneous environments. Methodologically, this research will combine detailed tree-ring analyses of disturbance and climatic variation with GIS-analyses of the spatial interactions of past disturbance events in relation to topographic setting. This multi-scale empirical analysis will elucidate the relative roles of fine- versus coarse-scale constraints on disturbance processes. The results of the project will be of importance to forest resource planning and management in National Parks and National Forests in Colorado. In particular, legacies left in the landscape by prior disturbance by fire and insect outbreaks need to be considered when planning for the spread and severity of future disturbance events.