Physical and Chemical Limnology of Char Lake, Cornwallis Island (75° N Lat.)

Abstract

Seasonal data for several physical and chemical variables in Char Lake are given. Annual cycles of major solutes are influenced primarily by freeze–thaw cycles. Concentrations of most substances are increased by freezing–out during the winter. Because the lake does not circulate during maximum spring meltwater flow, this freezing-out maintains concentrations in the lake above those in inflow streams.Concentrations of phosphorus and nitrogen in the lake are low throughout the year. Precipitation contains little phosphorus or nitrogen. Input of phosphorus and nitrogen are calculated to be 0.016 and 0.314 g/m2, respectively. Retention of nutrients by the lake is lower than in temperate regions, although still quite efficient.With the exception of silica, return of ions from the sediments during winter was found to be negligible.Disturbance of one inflow stream due to airstrip construction caused great increases in concentrations of nitrogen, silica, chloride, sulfate, and bicarbonate in the stream.