Energy flow in an arctic aquatic ecosystem

• Main Author: Schell, D.M.
• Language: unknown
• Published: 2008
• Subjects: 54 ENVIRONMENTAL SCIENCES; AQUATIC ECOSYSTEMS; ENERGY BUDGETS; ARCTIC REGIONS; TUNDRA; NATURAL RADIOACTIVITY; COASTAL REGIONS; ALASKA; CARBON 14 COMPOUNDS; CARBON 13; ISOTOPE RATIO; MOSSES; DEER; Arctic; Tundra; Alaska
• Online Access: http://www.osti.gov/servlets/purl/10137219; https://www.osti.gov/biblio/10137219; https://doi.org/10.2172/10137219

Natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. Our overall goals are to a determine if carbon is accumulating in upland and coastal tundra; determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers. Past work on fishes, birds, and the prey species of insects and aquatic crustaceans has shown that peat carbon is very important in the energy supply supporting the food webs over the course of the year. Obligate freshwater fishes from the coastal lakes and Colville River have been shown to contain up to 60 percent peat carbon at the end of the winter season. In contrast, migratory shorebirds and passerines contained much smaller radiocarbon abundances in summer, indicating a major shift to recent in situ primary production in pond and stream ecosystems in summer months. For the past two years, we have narrowed our focus to the processes supplying carbon to the beaded stream system at MS-117 and have concentrated on determining the transfer and accumulation rates of carbon in the watershed.