Tree heights and diameters: Wickersham fire sites (at the Viereck thaw probe locations), 1995 and 2004

In June of 1971, the Wickersham fire burned 6313 ha in an open black spruce forest underlain with permafrost and provided an opportunity to study fire and fireline effects on the rate and patterns of permafrost, soil, and vegetation recovery. When wildfire burns through a northern black spruce forest the degree of soil organic layer consumption greatly influences the post-fire community characteristics. The construction of firelines with heavy machinery involves the complete removal of vegetation and the soil organic layer down to mineral soil and likewise affects the community characteristics after fire and fire suppression. This long-term study is part of a comparison between the vegetative communities of firelines, burned, and unburned open black spruce forests underlain by ice rich permafrost. In this study, tree diameters and heights were measured in an unburned control plot and in a heavily burned plot. There were no trees to measure in the fireline plot. Tree heights and diameters at breast height were measured for tree species in the heavily burned and unburned control sites on the east side of Cushman Creek of the Wickersham Fire Sites. This dataset focuses on the trees of the east side sites (2004 and 2130) to corroborate the detailed studies of active layer depths and fireline surface level changes previously published (Viereck, 1982; also see datasets in related material section) and in preparation.1971年6月，威克舍姆火灾（Wickersham fire）在一片基底为多年冻土（permafrost）的开阔黑云杉林（black spruce forest）中过火总面积达6313公顷，该事件为研究火灾及防火隔离带（fireline）对多年冻土、土壤与植被恢复速率及格局的影响提供了理想契机。当野火蔓延至北方黑云杉林时，土壤有机层的消耗程度会极大影响火后群落特征。利用重型机械修筑防火隔离带的作业，会将植被及土壤有机层完全移除直至矿质土壤（mineral soil）层，同样会改变火灾及灭火后的群落特征。本长期研究旨在对比富冰多年冻土基底的防火隔离带、过火区域与未过火开阔黑云杉林的植物群落特征。本研究在未过火对照样地与重度过火样地中测量了各树木物种的树高与胸径（diameter at breast height），而防火隔离带样地中无树木可供测量。 研究人员在威克舍姆火灾场址库什曼溪东侧的重度过火与未过火对照样地中，针对各树木物种测量了其树高与胸径。本数据集聚焦于东侧样地（编号2004与2130）的树木数据，旨在佐证此前已发表（Viereck, 1982；另见相关资料部分中的数据集）及待发表的关于活动层厚度与防火隔离带地表变化的详细研究成果。