Multi-Scale Reconstructions of Human-Climate-Fire Interactions in Mixed-Conifer Forests of the Northern Rockies

这项研究项目将重建历史火灾在过去几千年中混合针叶林部落土地上的北方落基山脉。 类似的森林在北美西部内陆广泛分布，但人们对它们历史上的火灾动力学知之甚少，更不知道人类如何影响这些火灾。 最近的大火和未来几十年火灾活动增加的预测促使美国的土地管理机构开始广泛的恢复工作，旨在减少火灾风险和危害。 与此同时，美国西部的野火扑灭费用已上升到每年10亿美元以上，现在消耗了美国林务局近一半的预算。 迫切需要更好地了解应用燃料处理的历史背景，以减少美国西部混合严重森林类型的火灾风险。部落成员和森林管理者对保护历史连续性和将文化上重要的做法纳入其管理战略。 该项目将澄清古代和近代人类对火灾制度和混合针叶林的影响的作用。 项目结果将提供一个机制的理解因素塑造目前的林分特点。 该项目将有助于就古代和近代人类活动对温带森林的影响进行科学辩论。 该项目将加强对面对不断变化的气候条件和土地使用的生态复原力的基本了解，并将促进对经历多种自然和人为压力的生态系统进行科学管理。 该项目将通过雇用10多名本科生和两名研究生，包括美洲土著学生和部落学院的学生，帮助教育和培训新一代的火灾和森林管理人员和研究人员。 该项目还将帮助建立一个部落学院的研究能力，该项目将解决以下问题有关的过去和未来的控制火灾和森林生态系统：如何可变的火灾制度在混合针叶林的北方落基山脉？ 干燥的针叶混交林对最近火灾活动、昆虫爆发和土地利用变化的增加是否比中针叶林具有更强的内在弹性？ 治疗的目的是恢复基准生态系统动态在混合针叶林代表历史的自然和人类干扰过程？ 从过去的火灾-人类-气候相互作用中吸取的经验教训如何帮助土地管理者通过未来的森林管理支持森林复原力，最终降低灭火成本？ 研究人员将通过结合从湖泊沉积物和树木年轮中重建的火灾和植被历史来回答这些问题，这些树木年轮是从早期人类活动密集的成对地点网络中取样的，而这些地点在很大程度上与早期人类活动隔离。 他们将把这些火的历史与多世纪的气候重建进行比较。 该项目将阐明影响生态系统变化的自然和人为因素之间的相互作用，以便为恢复和管理战略提供信息，这些战略以最终降低野火风险和灾害成本的方式支持森林复原力。

This research project will reconstruct historical fires over the past several thousand years in mixed-conifer forests on tribal lands in the northern Rockies. Similar forests are widespread in the interior of western North America, but little is known about their historical fire dynamics, and even less is known about how humans may have influenced those fires. Recent large fires and projections of increased fire activity in the decades ahead have prompted land-management agencies in the U.S. to initiate widespread restoration efforts aimed at reducing fire risk and hazard. At the same time, wildfire suppression costs in the western U.S. have risen to more than $1 billion annually and now consume nearly one-half of the U.S. Forest Service budget. There is a critical need to better understand the historical context for applying fuel treatments intended to reduce fire risk in mixed-severity forest types across the western U.S. The need to better understand the historical context for forest management is particularly compelling on tribal lands, where tribal members and forest managers have a strong interest in preserving historical continuity and incorporating culturally important practices into their management strategies. The project will clarify the role of ancient and recent human influence on fire regimes and mixed-conifer forests. Project results will provide a mechanistic understanding of factors shaping current forest stand characteristics. The project will contribute to scientific debates concerning the influence of both ancient and recent human activities on temperate forests. The project will enhance basic understanding of ecological resilience in the face of changing climatic conditions and land use, and it will facilitate the development of science-based management for ecosystems experiencing multiple natural and human-caused stressors. This project will help educate and train a new generation of fire and forest managers and researchers by employing more than ten undergraduates and two graduate students, including Native American students and students from tribal colleges. The project also will help build research capacity at a tribal college.This project will address the following questions related to past and future controls on fire and forest ecosystems: How variable were fire regimes in mixed-conifer forests of the northern Rockies? Are drier mixed-conifer forests inherently more resilient than mesic ones to recent increases in fire activity, insect outbreaks, and land-use change? Are treatments aimed at restoring baseline ecosystem dynamics in mixed-conifer forests representative of historical natural and human disturbance processes? How can lessons from past fire-human-climate interactions help land managers support forest resilience with future forest management in ways that ultimately reduce fire suppression costs? The investigators will answer these questions by combining fire and vegetation histories reconstructed from lake sediments and tree rings sampled from a network of paired sites in which early human activity was intensive versus paired sites that were largely isolated from early human activity. They will compare these histories of fire to multi-century reconstructions of climate. This project will clarify interactions between natural and human factors that influence ecosystem change in order to inform restoration and management strategies that support forest resiliency in ways that ultimately reduce the cost of wildfire risk and hazard.