RUI: Collaborative Research: Legacies of Ojibwe Land Use in the Fire Regimes and Vegetation Communities of the Boundary Waters Canoe Area Wilderness

这一合作研究项目将重建明尼苏达州北部边界水域独木舟地区荒野地区一系列遗址的火灾历史，以评估美洲原住民土地利用活动对该地区火灾制度和植被格局的潜在影响。该项目将增进关于人类对通常被认为是原始景观的影响的程度和程度的基本知识，并解决将人类作为变化的推动者纳入北美森林的生态基线问题。这个项目的发现应该有助于对1964年《荒野法案》所界定的荒野概念进行创新思考。在这个项目的实施过程中，研究、教育和指导活动将完全整合起来，以加强本科生的学习，并为研究生未来的科学生涯做好准备。通过这项研究建立的调查人员和合作将为资源管理者提供关键信息，有助于他们对荒野景观的长期规划和管理。20世纪的灭火是人类对森林火灾最明显和最戏剧性的影响之一，直接导致树木密度增加和随后的燃料驱动的火灾事件，这在过去几个世纪可能是史无前例的。然而，在有效的灭火措施出现之前，美洲原住民焚烧对景观结构和组成的潜在作用受到的关注要少得多，但居住在研究地区的奥吉布人和其他美洲原住民的焚烧可能会对目前的森林结构和组成产生重大影响。美洲原住民群体使用火来操纵他们的周围环境，这可能增加了许多地区的火灾频率，今天这些地区被认为是相对自然的。如果美洲原住民在历史上增加了火灾频率，而不是闪电点火的频率，那么今天被作为自然区管理的地区的植被格局可能是过去人类活动的遗产，而不是以前意识到的。因此，随着管理机构转向积极的管理策略，通过应用火等干扰过程来缓解外来压力，如入侵物种和气候变化，了解美洲原住民使用火的相对影响至关重要。为了进行这个项目，调查人员与美国农业部林业局考古学家合作，确定已知奥吉布使用的遗址，以及很少或根本没有奥吉布使用证据的遗址。研究人员将使用树木年轮来重建每个地点过去的火灾和森林人口统计模式。他们将比较每组地点在火灾状况特征(火灾频率、火灾同步性和火灾与气候的关系)和植被模式(林龄结构、组成和树冠结构)方面的特征。这两个群体之间火灾历史和植被模式的系统差异将为当代森林中奥吉布土地利用的遗产提供量化证据，对定义荒野的概念和管理具有直接影响。过去的火灾历史模式也将与现代的火灾和闪电记录进行比较，以评估过去的火灾历史是否类似于在现代景观中观察到的点火或雷击密度。

This collaborative research project will reconstruct fire histories across a network of sites in the Boundary Waters Canoe Area Wilderness in northern Minnesota in order to assess the potential impact of Native American land-use activities on fire regimes and vegetation patterns of the region. The project will advance basic knowledge about the extent and magnitude of human influence on landscapes often considered pristine and address the inclusion of humans as agents of change within ecological baselines of North American forests. The findings of this project should contribute to innovative thinking about the concept of wilderness as defined under the 1964 Wilderness Act. During the conduct of this project, research, education, and mentoring activities will be fully integrated to enhance undergraduate learning and prepare graduate students for future scientific careers. The investigators and collaborations built through the research will provide critical information to resource managers that will aid their long-term planning and management of wilderness landscapes.The suppression of fires over the 20th century is one of the most visible and dramatic human impact on forest fires, leading directly to increasing tree densities and subsequent fuel-driven fire events that may be unprecedented over the last several centuries. The potential role of Native American burning on landscape structure and composition prior to the advent of effective fire suppression has received much less attention, however, but burning by the Ojibwe who lived in the study area and other Native Americans may have a substantial impact on present forest structure and composition. The use of fire by Native American groups to manipulate their surroundings may have augmented fire frequencies in many areas that are today considered relatively natural. If Native Americans historically augmented fire frequencies beyond the frequencies that would have occurred from lightning ignitions, vegetation patterns in areas that today are managed as natural areas might be a legacy of past human activity than previously had been realized. Understanding the relative impact of Native American fire use therefore is critically important as management agencies shift to active management strategies designed to mitigate external pressures, such as invasive species and climate change, through the application of disturbance processes like fire. To conduct this project, the investigators have worked with USDA Forest Service archaeologists to identify sites with known Ojibwe use alongside sites with little or no evidence of Ojibwe use. The researchers will use tree-rings to reconstruct past fire and forest demographic patterns at each site. They will compare the characteristics between each set of sites in terms of fire regime characteristics (fire frequency, fire synchrony, and fire-climate relationships) and vegetation patterns (forest age structure, composition, and canopy structure). Systematic differences in the fire history and vegetation patterns between the groups will provide quantitative evidence of the legacies of Ojibwe land use in contemporary forests, with direct implications for defining the concept and management of wilderness. Past fire history patterns also will be compared with modern records of fire and lightning to assess whether past fire history is similar to ignition or lightning strike density observed within the modern landscape.