Ecosystem response to the repeated interaction of disease and fire

该奖项的重点是火灾和森林疾病之间的相互作用的长期研究，橡树猝死，在大苏尔地区的加州。虽然火灾是健康的加州森林生态的重要组成部分，但橡树猝死症是最近引入的一种疾病，在过去20年里，这种疾病已经杀死了加州沿海数百万棵树。被疾病杀死的树木作为燃料，可能会增加野火点燃、蔓延和强度增加的风险。 虽然火灾和疾病都造成大量树木死亡，但每种干扰都会对森林造成不同类型的影响和恢复。为此，拟议的研究旨在确定多种和改变的干扰如何相互作用，以确定再生植物群落的组成，并塑造未来干扰的严重程度，频率和时间。 野火的威胁在整个加州和美国西部的许多社区的政策决策中起着重要作用。随着越来越多的人生活在森林中和森林附近，扑灭野火的成本急剧增加。了解疾病和火灾如何相互作用影响森林对于灭火、保护社区以及在灾难性火灾和疾病爆发后帮助森林恢复非常重要。将在2006年建立的80，000公顷地块网络中检查大苏尔森林中的疾病-火灾相互作用，以研究橡树猝死。2008年和2016年，大火在整个阴谋网络中燃烧，提供了一个大规模研究疾病-火灾相互作用的机会。 大苏尔地块网络的初步结果表明，这些森林生态系统正在走向新的干扰制度与疾病和火灾之间的复杂相互作用，影响树木和灌木物种，否则弹性的干扰。由于疾病的存在，野火严重程度的增加可能会增加不易感染疾病的树种的死亡率，改变森林组合和生物地球化学循环，并最终为火灾和疾病的联合干扰创造背景，并将重新出现在整个景观中。研究方法包括监测长期田间小区的植被、病原体和土壤养分，病原体的实验室定量以及统计建模。拟议的研究计划预计，戏剧性的树木死亡率，由于橡树猝死在大苏尔将持续多年，从而影响燃料装载和随后的自然火灾regimes.This奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

This award focuses on the long-term study of interactions between fire and a forest disease, Sudden Oak Death, in the Big Sur region of California. While fire is an important part of the ecology of healthy California forests, Sudden Oak Death is a recently introduced disease that has killed millions of trees in coastal California over the past 20 years. Disease-killed trees serve as fuel and may increase the risk for the ignition, spread, and increased intensity of wildfires. While fire and disease both cause extensive tree death, each disturbance type results in different types of impacts and recovery of forests. To that end, the proposed research seeks to determine how multiple, and altered, disturbances interact to determine the composition of the regenerating plant community and shape the severity, frequency, and timing of future disturbances. The threat of wildfire plays a major role in policy decisions in many communities throughout California and the western United States. The cost of fighting wildfires has increased dramatically as more people live in locations in and near forests. Understanding how disease and fire interact to impact forests is important in fighting fires, protecting communities, and in aiding the recovery of forests after catastrophic fire and disease outbreak.Disease-fire interactions in Big Sur forests will be examined across an 80,000 ha plot network that was established in 2006 to study Sudden Oak Death. Large fires burned across the plot network in 2008 and in 2016, providing an opportunity to study disease-fire interactions at a very large scale. Initial results from the Big Sur plot network indicate that these forest ecosystems are moving toward novel disturbance regimes with complex interactions between disease and fire, impacting tree and shrub species that are otherwise resilient to either disturbance. Increases in wildfire severity due to the presence of disease can increase mortality of tree species not susceptible to disease, alter forest assemblages and biogeochemical cycles, and ultimately, create the context for how the joint disturbances of fire and disease and will re-emerge across the landscape. The research approach includes monitoring the vegetation, pathogens, and soil nutrients of the long-term field plots, laboratory quantification of pathogens, as well as statistical modeling. The proposed research plan anticipates that the dramatic tree mortality due to Sudden Oak Death in Big Sur will continue for many years, thereby influencing fuel loading and subsequently natural fire regimes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.