Contributions of Suspended and Dissolved Substances to the Arctic Ocean During Breakup of the Colville River, Alaska.

摘要

During May and June 1973, water samples were collected from the distributary channels and nearshore waters of the Colville River delta, Alaska, in order to determine the river's contribution of suspended and dissolved substances to the Arctic Ocean. Sampling in late winter and during prebreakup, breakup, and postbreakup flooding provided information on the spatial distribution and temporal variation of these substances. Suspended materials, largely absent in winter, were abundant during flooding. Some of this load was deposited on the sea ice, over which much of the floodwater moved during breakup; the rest was carried seaward beneath the sea ice in the freshwater wedge that forms after floodwater drains through the ice. The interface between the advancing freshwater and the seawater beneath is narrow, and sharp contrasts in temperature, salinity, and nutrient concentrations occur across it. Organic carbon, in both its dissolved and its particulate form, inorganic nitrogen, phosphate phosphorus, and silicate silicon all increased in concentration during flooding. Such seasonal additions suggest that the Colville River is a major contributor of essential nutrients to the nearshore waters of the Arctic Ocean. (Author)