Full Stack (NodeJS)
These following paragraphs describes the work done during my master degree at Université du Québec à Rimouski (2013-2016)
Many species are not migrating fast enough to keep pace with the rapidly changing climate. It is well known that trees experience long time lags in their migration responses because they are sessile, long-lived and have a relatively short dispersal ability. Current approaches to forecast range shifts under climate change, such as Species Distribution Models, cannot account for the particularities of forest ecosystems because they assume infinite dispersal and an instantaneous response to climate change. Here, we propose a new modelling approach based on metapopulation theory to account for dispersal limitations, biotic interactions and the demography of the temperate forest. Our objective is to assess if the northeastern American temperate forest will be able to track its climatic optimum by the end of this century.
We performed simulations on the boreal-temperate ecotone using State and Transition Models (STMs), wherein forest communities are classified in 4 states: boreal, temperate, mixed and stands in regeneration. Transitions among states are calibrated from several long-term forest plot surveys from the United States and Canada. We find that the temperate forest will move only 14±2.0 km into the boreal forest by the end of this century, contrary to predictions from standard statistical models that the temperate forest will shift northward by 238.79±34.24 km. We also find that most of the expected transitions will be the conversion from mixed to pure temperate stands. A comparison with an infinite dispersal scenario reveals that biotic interactions and stand replacement dynamics are the most significant factors limiting migration rate of forest trees. We conclude that the temperate forest has a low resilience to climate change because of their low demography and competitive interactions with resident trees.