Limnology of 46 lakes and ponds on Banks Island, N.W.T., Canadian Arctic Archipelago

The goal of this study was to describe and quantify the physical and chemical limnological properties of 46 lakes and ponds on Banks Island, to explore the effects of ecoclimatic differences on the water chemistry of these study sites, and to establish baseline conditions for this previously unexplored limnological region, which could then be used in subsequent long-term environmental monitoring programs. A key finding was that the study sites on Banks Island represented a large nutrient concentration gradient from ultra-oligotrophic to hypereutrophic waters. In general, the study sites were relatively nutrient rich by Arctic standards (i.e. mean total nitrogen (TN_mean)=504.2μg/l and mean total phosphorus (TPU_mean)=18.0μg/l); concentrations that are amongst the highest of any previous limnological survey from similar latitudes. Dissolved organic carbon (DOC) concentrations were also some of the highest reported to date amongst all other Canadian Arctic island limnological surveys. These values reflect the milder climate, concentrated animal life and lushness of Banks Island, as compared to other Canadian Arctic Archipelago islands. Principal components analysis (PCA) separated sites along a conductivity/ionic and elevation gradient on Axis 1 (λ₁=0.343), and a metal (Fe, Zn, Al) and alkalinity-related (DIC, pH) gradient on the second axis (λ₂=0.187). Canonical variate analysis (CVA) was used to explore the classification of the study sites into Low Arctic, Mid Arctic or High Arctic designations based on their limnological characteristics.