PHYSICAL AND CHEMICAL LIMNOLOGY OF 59 LAKES LOCATED BETWEEN THE SOUTHERN YUKON AND THE TUKTOYAKTUK PENINSULA, NORTHWEST-TERRITORIES (CANADA)

Water chemistry and other Limnological data gathered for 59 lakes in t he Yukon and the adjacent Northwest Territories (Canada) were interpre ted using Linear regression and principal components analysis. The stu dy sites represent lakes from a wide range of ecoclimatic regions, spa nning large latitudinal (60 degrees 37'-69 degrees 35'N) and altitudin al gradients (15-1387 m above sea level). Water samples collected from each lake were analysed for concentrations of major ions, trace metal s, nutrients, and chlorophyll a. Most of the lakes were dilute (mean c onductivity = 160 mu S.cm(-1)) and slightly acidic to alkaline (pH ran ge = 5.9-9.3). Their ionic composition varied from Ca-Cl-Na waters nea r the Arctic Ocean to Ca-HCO3 waters further inland, reflecting differ ences in local drainage basins and proximity to the sea. Arctic and al pine sites generally showed many similarities, but considerable differ ences in water chemistry were observed among sites in the interior of the Yukon Territory. These can be related mainly to differences in bed rock geology and catchment vegetation.