Climate change, biodiversity and northern ecosystems

Ecological and hydrological perturbations resulting from climate change and affecting northern ecosystems have become increasingly evident. In particular, climate change could affect the functioning of peatland ecosystems, a dominant feature of the landscape in eastern Canadian North. Peatlands play central roles in the regulation of the global carbon cycle and house a unique component of global biodiversity. Peatlands and other types of wetlands cover less than 1% of the Earth’s surface yet harbor 10% of all known animal species, 60% of which are aquatic insects. Insects play a wide variety of trophic and functional roles in wetlands as scavengers, grazers, predators, vectors of disease and pollinators yet they are understudied. Because of their high mobility and sensitivity to environmental change, fluctuations in insect abundance, composition and diversity can serve as excellent indicators of climate change impacts. Fluctuations in the structure of aquatic insect communities not only indicate environmental change, they also reflect the functionality (i.e. health) of wetland ecosystems. Given that they are important breeding grounds for biting insects, wetland ecosystems have direct impacts on the daily life of northern communities. Not only are biting insects a major nuisance, Inuit elders have noted the arrival of new insects in northern villages. Working at five field stations spread along a latitudinal gradient, our research will aim to develop indicators of climate change for wetland ecosystems in the subarctic and low arctic regions of northern Quebec.