THE HYDRAULIC CHARACTERISTICS AND GEOCHEMISTRY OF HYPORHEIC AND PARAFLUVIAL ZONES IN ARCTIC TUNDRA STREAMS, NORTH SLOPE, ALASKA

• Main Authors: K Edwardson, W Bowden, C Duham, J Morrice
• Format: Text
• Language: unknown
• Published: 2005
• Subjects: Arctic; north slope; permafrost; Tundra; Alaska
• Online Access: http://oaspub.epa.gov/eims/eimsapi.dispdetail?deid=66450

Sodium bromide and Rhodamine WT were used as conservative tracers to examine the hydrologic characteristics of seven tundra streams in Arctic Alaska, during the summers of 1994-1996. Continuous tracer additions were conducted in seven rivers ranging from 1st to 5th order with samples collected from instream, hyporheic, and parafluvial locations. - - - The hyporeic zone of all four reaches was a source of nitrate, carbon dioxide, and ammonium to the channel water based on the average concentration of upwelling waters. Increased contact time with hyporheic and parafluvial zones was related to decreased temperature and increased conductivity. Net nitrogen flux from the hyporheic zone was equivalent to 14-162% of benthic N uptake requirements for the Kuparuk River. These observations are important because we expected that the presence of continuous permafrost in this Arctic environment would limit the importance of hyporheic processes, either physically or biogeochemically. Instead, we found that biogeochemical process in the hyporheic zone of these Arctic streams are at least as important as it is in similar temperate stream ecosystems.