Historic climate-fire-vegetation interactions of the West versus East Kootenays: Implications of climate change and fire suppression

我们的研究比较了东库特奈区克兰布鲁克附近的约瑟夫-金溪流域和西臂省立公园纳尔逊附近的五英里-拉斯卡溪流域，西臂省立公园位于不列颠哥伦比亚省东南部的西库特奈区。理论火灾植被模型表明，历史上的火灾制度在这两个地区有很大的不同。我们的研究测试的假设，人类的土地利用，灭火和气候变化的综合影响均匀的火灾制度在两个位置。目前，这两个地区发生严重火灾的风险很高，主要是由于东库特奈研究区干燥森林的火灾排除，以及西库特奈研究区中温带森林日益频繁的干旱。 我们将使用一个多代理古生态学的方法来检查和比较历史的气候，植被和火灾在一系列的时间尺度在两个地点在西部和东部库特奈地区东南部不列颠哥伦比亚省。对湖泊沉积物的古生态学研究将量化1000至10,000年期间火灾状况和森林组成的变化。树木生态学（树木年轮）分析将通过以下方式解决这些变化发生的机制：（a）重建过去300至500年的气候，（B）通过分析火痕量化历史火灾频率，（c）调查年际至十年气候变化对火灾状况的影响。我们的目标是：（a）量化火灾频率和严重程度在空间和时间上的自然变化范围，（B）预测在不同气候变化情景影响下的未来火灾状况，以及（c）预测在气候变化和改变的干扰制度的影响下未来的主要植被。我们将与卑诗省森林和山脉部、卑诗省公园和环境部、纳尔逊市和克兰布鲁克市以及Tembec等当地森林管理公司的代表合作，确定因人类土地使用和灭火而显著改变的景观部分，这些部分需要生态恢复和/或缓解，以保护经济和文化资源。

Our research compares the Joseph-Gold Creek watersheds near Cranbrook in the East Kootenay district and the Five Mile-Lasca Creek watersheds in West Arm Provincial Park near Nelson in the West Kootenay district of southeastern British Columbia. Theoretical fire-vegetation models suggest the historic fire regimes differed considerably in the two districts. Our study tests the hypothesis that the combined effects of human land use, fire suppression and climate variation have homogenized the fire regimes in the two locations. Risk of severe fires is presently high in both locations, primarily due to fire exclusion in the drier forests of the East Kootenay study area and increasingly frequent droughts in the more mesic forests of the West Kootenay study area.  We will use a multi-proxy paleoecological approach to examine and compare the history of climate, vegetation and fire at a range of temporal scales at two locations in the West and East Kootenay districts of southeastern British Columbia. Paleoecological studies of lake sediments will quantify changes in fire regimes and forest composition over periods of 1000 to 10,000 years. Dendroecological (tree-ring) analyses will address the mechanisms by which these changes occur by (a) reconstructing climate over the last 300 to 500 years, (b) quantifying historic fire frequency through analysis of fire scars, and (c) investigating the impacts of inter-annual to decadal climate variation on fire regimes.Ultimately, we aim to (a) quantify the natural range of variability in fire frequency and severity, both spatially and temporally, (b) predict future fire regimes under the influence of different scenarios of climate change, and (c) predict future dominant vegetation under the influence of climate change and altered disturbance regimes. We will collaborate with representatives from the BC Ministry of Forests and Range, BC Parks and Ministry of Environment, the Cities of Nelson and Cranbrook and local forest management companies such as Tembec, to identify segments of the landscape significantly altered by human land use and fire suppression that require ecological restoration and/or mitigation to protect economic and cultural resources.