Fire and biogeoscience plant ecology

拟议的四个研究项目以扩展两个学科的方式将生态和物理（火灾和地貌学）过程结合在一起。 1）景观开发-植物耐受性项目开辟了新天地，利用海峡山坡综合景观开发模型创建一个具有已知气候、水文和地貌过程的地形，然后将不同物种耐受性的植物群落（对应于真实群落）置于该地形的湿度梯度上。该方法将有助于确定不同气候和地貌对物种多样性的作用。 2）海拔林线通常由气候（寒冷）狭义地定义；在这个项目中，我们将研究也影响林线的地貌过程（斜坡过程引起的基质不稳定和缺水）。在气候变化的时期，这些其他林线过程也可能发生变化。 3) 野火通过阴燃燃烧去除土壤中的 F 和 H 有机层，使树木更成功地再生。在这个项目中，我们将确定 F 层和 H 层的水分预算——阴燃燃烧最重要的过程。我们打算为水分预算创建一个小分水岭（五阶流）分布式模型，可用于预测 F 层和 H 层水分。 4）最后，我们提出了一个关于地表火灾造成的树木死亡的空间明确模型。该项目汇集了荒地火灾动力学模拟器和树木死亡率模型，我们开发了该模型来预测一系列火灾强度下的树木死亡情况。在越来越多地使用低强度管理燃烧的时代，了解热传递如何杀死树木非常重要，以便可以设计燃烧以达到所需的生态效果。

The four proposed research projects bring together ecological and physical (fire and geomorphology) processes in a manner that expands both disciplines. 1) The landscape development-plant tolerance project breaks new ground by using the Channel Hillslope Integrated Landscape Development Model to create a terrain with known climatic, hydrologic, and geomorphic processes and then putting plant communities of different species tolerances (corresponding to real communities) on this terrain's moisture gradients. The approach will help determine the role of different climates and geomorphology on species diversity. 2) Altitudinal treeline is usually narrowly defined by climate (cold); in this project we will examine the geomorphic processes (substrate instability and water shortage caused by slope processes) that also influence treeline. In a time of changing climate these other treeline processes may also change. 3) Wildfires remove the F and H organic layers of the soil by smoldering combustion and allow more successful tree regeneration. In this project we will determine the moisture budgets for the F and H layers-the most important process for smoldering combustion. We intend to create a small watershed (fifth-order stream) distributed model for the moisture budgets that can be used to predict F- and H-layer moisture. 4) Finally, we propose a spatially explicit model of tree mortality from surface fires. This project brings together the Wildlands Fire Dynamics Simulator and the tree mortality model which we have developed to predict tree death under a range of fire intensities. In a time of increased use of low intensity management burns, it is important to understand how heat transfer kills the trees so that the burns can be designed for the desired ecological effect.