Doctoral Dissertation Research: Anthropogenic Impacts on Fire and Forest History in Native Yellow Pine and Mixed Hardwood-Pine Communities of the Southern Appalachians

火在阿巴拉契亚山脉南部的长期作用及其与南部黄松的相互作用是一个引起猜测的主题，但几乎没有确凿的证据。 原住民和欧美社会在阿巴拉契亚南部地区留下了独特的土地使用特征，但随后的每一组居民在多大程度上改变了森林组成和火灾发生？ 博士生克里斯托弗安德伍德，在田纳西大学的萨莉霍恩博士的监督下，通过恢复，鉴定和测定土壤木炭的年代，试图记录田纳西州大烟山国家公园现代黄松和混合硬木松树森林的森林和火灾历史。 需要测试的过度假设是，土著居民或闪电引发的史前火灾是否造成了足够的干扰，以维持岩石斜坡和山脊顶部以外的黄松群落。 从公园西部的八个地点回收了四十八个用于木炭分析的土芯。 在另一项研究中，其他研究人员量化了这八个地点的现代森林组成和树木年龄结构，并根据对火灾后树木的分析重建了过去几个世纪的火灾。 宏观木炭碎片的鉴定和定年将扩展火灾的树木年代学记录，并提供过去当地火灾和森林组成的证据，这是通过任何其他方法都无法获得的。 虽然木炭组合在表层土壤中反映森林组成的历史火灾时，木炭组合在深度包括显着较老的颗粒，提供证据，当地的森林组成之前，欧洲-美国定居的时期。 比较地表木炭组合最近的森林组成植被调查记录提供了一个基础，校准这种深层木炭提供的分类信号。这项研究将是第一个专门解决的空间-时间模式的森林组成和火灾历史在阿巴拉契亚山脉南部使用分类确定的土壤木炭作为主要代理。 需要有关早期历史和史前时期森林组成和火灾历史的信息，以帮助土著和欧美人类对森林组成和火灾历史的影响。 这一研究设计也可以应用于其他地区，以促进类似的研究。 数据和结论将有助于森林和公园管理人员作出有关森林和火灾管理的养护和管理决定。 关于过去森林火灾和当前火灾发生情况与过去情况的偏离的信息，对于指导森林管理做法和证明其合理性非常重要，例如使用规定的燃烧来恢复生态系统。 更好地了解长期火灾植被动态不仅对阿巴拉契亚山脉南部森林群落的健康和保护很重要，而且对保护大烟山国家公园不断扩大的森林-城市界面沿着的人类生命和财产也很重要。

The long-term role of fire in the southern Appalachians and its interplay with southern yellow pines is a theme that has generated speculation, but little hard evidence. Indigenous and Euro-American societies have left unique signatures of land use in the southern Appalachian region, but to what extent has each subsequent group of inhabitants created changes in forest composition and fire occurrence? Doctoral student Christopher Underwood, under the supervision of Dr. Sally Horn at the University of Tennesse seeks to document forest and fire history in modern yellow pine and mixed hardwood-pine forests of Great Smoky Mountains National Park, Tennessee, through the recovery, identification, and dating of soil charcoal. The over-arching idea to be tested is whether prehistoric fires set by indigenous occupants or lightning caused sufficient disturbance to maintain yellow pine communities on sites other than rocky slopes and ridge tops. Forty-eight soil cores for charcoal analysis have been recovered from eight sites in the western portion of the park. In a companion study, other researchers have quantified modern forest composition and tree age structures at the eight sites, and have reconstructed fires over the past several centuries based on analyses of fire-scarred trees. The identification and dating of macroscopic charcoal fragments will extend the dendrochronological record of fire, and provide evidence of past local fires and forest composition that cannot be obtained through any other method. While charcoal assemblages in surface soils reflect forest composition at the time of historic fires, charcoal assemblages at depth include significantly older particles that provide evidence of local forest composition before the period of Euro-American settlement. Comparing surface charcoal assemblages to recent forest composition as documented by vegetation surveys provides a basis for calibrating the taxonomic signal provided by this deep charcoal. This research will be the first to specifically address the spatio-temporal patterns of forest composition and fire history in the southern Appalachians using taxonomically-identified soil charcoal as the primary proxy. Information on forest composition and fire history in the early historic and prehistoric periods is needed to help place indigenous and Euro-American human impacts on forest composition and fire history in context. This research design can also be applied in other regions to facilitate similar studies. Data and conclusions will assist forest and park managers in making conservation and management decisions regarding forest and fire management. Information about past forest fires and the departure of current fire occurrences from past conditions is important for guiding and justifying forest management practices such as the use of prescribed burns for ecosystem restoration. A better understanding of long-term fire-vegetation dynamics is important not only to the health and conservation of the forest communities of the southern Appalachians, but also to the protection of human life and property along the expanding forest-urban interface of Great Smoky Mountains National Park.