Unravelling the effects of climate, composition and disturbance on forest productivity in the eastern boreal forest

不断变化的气候、干扰机制及其相互作用正在改变生态系统动态，特别是在高纬度森林；我的长期目标是评估东部北部大片地区优势树种几十年来的生长、种群和群落动态的变化。具体地说，我将结合从全省范围内收集的树木年轮核心得出的生长模式来研究大环境梯度下北方树木生长的气候敏感性。我们将调查物种和物种内的站点水平的反应。另一个短期目标是评估这些相同物种沿东西(降水)和南北(温度)梯度的种群数量(死亡率与补充量)和群落(组成变化)动态的长期变化。由于昆虫是外温动物，它们也应该对气候变暖做出强烈反应，并可能与使树木更容易死亡的水分压力相互作用。云杉幼虫是一种暴发的昆虫，随着其活动范围的扩大，在其传统活动范围内罕见的物种混合将会越来越多地受到攻击。不同混交北方树种的联合关系(增加的抗性与敏感性)的影响将作为北方森林系统在不同空间尺度上对非生物(气候)和生物(昆虫)胁迫的恢复力的替代。

Changing climate, disturbance regimes and their interactions are modifying ecosystem dynamics especially in high latitude forests; my long-term objective is to evaluate changes in decades of growth, population and community dynamics of the dominant tree species across a large region of the eastern boreal. Specifically, I will combine growth patterns derived from a province wide collection of tree ring cores to study climate sensitivity of the growth of boreal trees across large environmental gradients. We will investigate both species and site-level within species responses. Another short-term objective is to evaluate long-term changes in population (mortality vs recruitment) and community (changes in composition) dynamics of these same species along east-west (precipitation) and north-south (temperature) gradients. As insects are ectotherms they should also react strongly to warming and may interact with moisture stresses that predispose trees to increased mortality. With range expansion of the spruce budworm, an outbreaking insect, mixes of species that are rare in its traditional range will be increasing under attack. The effects of associational relationships (increased resistance vs susceptibility) in different mixes of boreal tree species will be used as a proxy for resilience to abiotic (climate) and biotic (insects) stresses in boreal forest systems at different spatial scales.