Surface Water Biogeochemistry In and Material Fluxes Through Small Rivers on the North Slope of Alaska During the Open Water Season from Spring-to-Fall

Abstract:

From June – October 2019, freshwater discharge measurements and surface water samples were collected at sites on the Sagavanirktok River and Kuparuk River on the North Slope of Alaska and from smaller streams feeding these rivers as they move northward from the Brooks Range to the coastal ocean through transitional and coastal plain tundra underlain by continuous permafrost. Results of the analysis of river and stream samples are presented to show that changes in freshwater discharge along with a deepening tundra active layer significantly influence surface water biogeochemistry in, material inputs to, and fluxes through (dissolved inorganic and organic constituents, suspended matter, and particulate organic matter) these rivers during the open water season from spring-to-late summer. Results of this study add to a growing baseline of data on seasonal variability in the biogeochemistry of smaller streams and rivers on the Alaskan North Slope and elsewhere that will be needed to better understand how regional changes in climate will alter watershed landscapes, hydrologic processes, biogeochemical cycles, material fluxes, and the interaction of Arctic rivers with the coastal ocean in the future.