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Jason Fellman

Abstract (from Global Change Biology): Mountain watersheds often contain a mosaic of glacier-, snow-, and rain-fed streams that have distinct hydrologic, temperature, and biogeochemical regimes. However, as glaciers diminish and precipitation shifts from snow to rain, the physical and chemical characteristics that make glacial or snowmelt streams distinct from rain-fed streams will fade. Among the unforeseen consequences of this hydrologic homogenization could be the loss of unique food webs that sustain aquatic consumers. To explore the impacts of a melting cryosphere on stream food webs, we parameterized an aquatic food web model with empirical physicochemical data from glacier-, snow-, and rain-fed streams in...
Categories: Publication; Types: Citation
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The Situk River is among the most productive resource in Alaska, with nine native fish species and 10 times the density of juvenile coho salmon than any other Southeast Alaskan watershed. The associated fisheries in the Situk River and its adjoining estuary drive a $2 million economy for the community of Yakutat (population 600), with 89 percent of the households harvesting salmon for subsistence purposes. The Yakutat foreland area that encompasses the Situk River watershed is a vast landscape of low gradient drainages with forested mosaics of side channels and pools that are responsible for up to 80 percent of coho salmon production. These highly productive aquatic habitats are sensitive to even small shifts in...
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Salmon that spawn and rear in Southeast Alaska watersheds are critically important to the region’s economic vitality and cultural identity. An estimated 90% of rural households in Southeast Alaska use salmon. Environmental changes that compromise the ability of these streams to support salmon could have dramatic consequences for the region. In particular, there is concern that climate change could undermine the capacity of the region’s streams to support productive fisheries. As a result, regional stakeholders are interested in identifying some of the potential impacts of climate change on watersheds that support abundant salmon. These stakeholders include federal and state agencies (U.S. Fish and Wildlife Service,...
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The Alaska Climate Adaptation Science Center (AK CASC) has a strong track record of working collaboratively with government entities to co-produce actionable science in areas including: high resolution dynamical and statistical downscaling, process and mechanistic-based ecosystem modeling, and glacier dynamics. The AK CASC is therefore uniquely positioned to facilitate and conduct science that informs specific management decisions within the state. The AK CASC is hosted by the University of Alaska Fairbanks (UAF) with consortium partners University of Alaska Anchorage and University of Alaska Southeast. To learn more about Host Agreement Projects and University of Alaska - Fairbanks projects, visit: https://akcasc.org/about-us/projects-overview/...
Abstract (from Biogeochemistry): Climate change is melting glaciers and altering watershed biogeochemistry across the globe, particularly in regions dominated by mountain glaciers, such as southeast Alaska. Glacier dominated watersheds exhibit distinct dissolved organic matter (DOM) characteristics compared to forested and vegetated watersheds. However, there is a paucity of information on how stream DOM composition changes as glaciers retreat and terrestrial ecosystem succession ensues. Importantly, it is unclear over what timescales these transformations occur. Here, we used bulk, isotopic and ultrahigh resolution molecular-level techniques to assess how streamwater DOM composition evolves in response to glacier...
Categories: Publication; Types: Citation
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