Geochemistry of Lake Sediments as a Record of Environmental Change in a High Arctic Watershed

A 1.93 m long sediment core was obtained from Fish Lake, Truelove Lowland, Devon Island, Nunavut, Canada. Multivariate statistical techniques using a wide range of chemical variables successfully reconstructed the late Holocene history of the Fish Lake watershed. Factor analysis identified six geomorphic mechanisms controlling the formation of sediments. Cluster analysis produced a grouping of core segments and discriminant analysis confirmed that 100% of the samples were correctly classified. The results indicated that the environmental history of the Fish Lake watershed in the past 6500 years can be divided into five phases. These are 6500-5700 years BP, 5700-1700 years BP, 1700-1000 years BP, 1000-600 years BP and 600 years BP to the present. In the Fish Lake watershed, during its time as a terrestrial system, the interactions of erosion, weathering, leaching, soil development, vegetation succession and climatic change have shaped the surrounding landscape as well as determined the evolution of the lake.