RAPID: Fire severity, topoclimates and resilience of oak woodlands: Responses to the 2017 Northern California wildfires

森林是自然世界的重要组成部分。它们为其他动植物创造栖息地，并提供重要的服务，如减少土壤侵蚀和在树干和根中储存碳。近年来，大型野火在加州和美国西部变得越来越常见，部分原因是夏季越来越炎热和干旱。这项研究将研究自然干扰，如野火，如何影响森林随时间变化的方式。例如，如果某些种类的树木比其他树木恢复得更快，那么构成这些森林的树木的类型可能会发生变化，这种变化可能会影响森林抵御未来干扰的能力。这项研究的结果将为我们了解、保护和管理森林栖息地的能力提供信息。本项目将培养1名博士后和不同背景的大专学生。该项目还将通过公共研讨会、网站和胡椒木保护区的其他努力，让公众和当地土地管理者参与进来。环境干扰和气候变暖之间的相互作用将在未来几十年植物群落的反应和变化方式中发挥关键作用。在林地和森林中，成熟树木的寿命和繁殖力具有很强的优先效应，限制了新物种的形成。考虑到当地气候条件的迅速变化，这种优先效应可能会减缓森林结构和组成变化的速度。索诺玛县2017年的塔布斯火灾是加州历史上最具破坏性的火灾之一，它提供了一个机会来探索火灾作为一种干扰，如何影响社区更替的速度和轨迹。更具体地说，这项研究将检验这样一个假设，即在与较凉爽的位置（即朝北的斜坡）相关的森林中，群落更替在火灾发生后将是最大的，但随着群落转向能够更好地忍受这种干扰的物种，物种组成的变化可能使它们对未来的火灾或干旱更具抵抗力。这项研究将在胡椒木保护区野外站进行，在火灾发生之前，这里就开始了对森林生态的长期研究，为量化不同物种树木的死亡率、顶杀和再生提供了一个独特的机会。将评估大约8000株植物，从小树苗到大树，以确定火灾损害和恢复，以及不同森林类型和景观位置的物种更替。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Forests are important components of our natural world. They create habitats for other plants and animals and provide important services, such as reducing soil erosion and storing carbon in their trunks and roots. In recent years, large wildfires have become increasingly common in California and the American West, due in part to increasingly hot summers and droughts. This study will examine how natural disturbances, such as wildfires, influence the way that forests change over time. If some kinds of trees recover more quickly than others, for example, the types of trees that make up these forests may change and this change could affect the forest's ability to withstand future disturbances. Results of this study will inform our ability to understand, conserve and manage forest habitats. This project will train a postdoctoral student and junior college students from diverse backgrounds. This project will also engage the public and local land managers through public workshops, a website, and other efforts by the Pepperwood Preserve.The interaction between environmental disturbances and a warming climate will play a critical role in the way that plant communities will respond and change in the coming decades. In woodlands and forests the longevity and fecundity of mature trees exert strong priority effects that limit the establishment of new species. This priority effect may slow the rate of changes in the structure and composition of the forest relative to what might be expected given rapid changes in local climatic conditions. The 2017 Tubbs Fire in Sonoma County, one of the most destructive complex of fires in California's history, provides an opportunity to explore how fire, as a disturbance, influences the rate and trajectory of community turnover. More specifically, this research will test the hypothesis that community turnover in forests associated with cooler positions (i.e. north-facing slopes) will be greatest following the fire, but that the resulting changes in species composition may make them more resistant to future fires or drought as the community shifts to species that are better able to tolerant such disturbances. The research will take place at the Pepperwood Preserve field station where long-term studies of forest ecology were initiated prior to the fire, providing a unique opportunity to quantify the mortality, top-kill and regrowth of trees of different species. About 8,000 individual plants, from small saplings to large trees, will be assessed to determine fire damage and recovery, and species turnover across different forest types and positions on the landscape.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.