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

不断变化的气候，干扰制度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几十年的增长，人口和群落动态的优势树种在整个东部北方大面积的变化。具体来说，我将结合联合收割机的生长模式，来自全省范围内收集的树木年轮核心，研究气候敏感性的北方树木生长跨越大的环境梯度。我们将调查两个物种和网站内的物种反应水平。另一个短期目标是评价这些相同物种在沿着东西（降水）和南北（温度）梯度上的种群（死亡率与补充率）和群落（组成的变化）动态的长期变化。由于昆虫是外温动物，它们也应该对变暖作出强烈反应，并可能与水分胁迫相互作用，使树木死亡率增加。随着云杉芽虫（一种爆发性昆虫）的范围扩大，在其传统范围内罕见的物种混合将受到越来越多的攻击。在不同的混合北方树种的关联关系（增加电阻与敏感性）的影响将被用作在不同的空间尺度的北方森林系统的非生物（气候）和生物（昆虫）应力的恢复力的代理。

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.