Dissertation Research: Ecological Effects of Temporal and Spatial Variability in the Disturbance Regime of an Old-growth Ponderosa Pine Forest

建议： DEB-0105155 PI：Swetnam，托马斯W.，和唐纳德·A. FalkTitle：论文研究：老黄松林干扰机制的时空变异的生态效应虽然西南部森林历史上一直受到干扰机制，包括频繁的火灾，许多树种对火灾敏感，特别是在青少年的发展状态。 奇怪的是，平均间隔发生的火灾甚至不包括像黄松这样的优势物种。 这表明，延长间隔无火需要建立黄松和其他火灾敏感的物种。 在此背景下，拟议的研究解决干扰生态学的核心问题，林业和资源管理的重要影响。火灾返回间隔的时间变化的影响进行了调查相对于人口的优势和次优势树种，因为这可能会对森林多样性产生重大影响。 此外，数学模型的开发，考虑火灾发生在指定区域内的可能性。 这提供了定量的见解有关的规模的影响扰动。

Proposal: DEB-0105155PI: Swetnam, Thomas W., and Donald A. FalkTitle: Dissertation Research: Ecological Effects of Temporal and Spatial Variability in the Disturbance Regime of an Old-growth Ponderosa Pine ForestAlthough southwestern forests historically have been subjected to a disturbance regime that includes frequent fires, many tree species are sensitive to fire, especially during juvenile states of development. Paradoxically, fires occurring at mean intervals should exclude even dominant species such as Ponderosa Pine. This suggests that extended intervals without fire are required for the establishment of Ponderosa pine and other fire-sensitive species. Within this context, the proposed research addresses central issues in disturbance ecology with important implications to forestry and resource management. The effects of temporal variation in fire-return intervals are investigated with respect to the demography of dominant and sub-dominant species of tree, as this can have a significant impact on forest diversity. In addition, mathematical models are developed which consider the likelihood of fires occurring within a specified area. This provides quantitative insights concerning the scaling of effects for disturbance.