• The archaeology of human- dog relations in Northwest Alaska

      Hill, Erica (Routledge, 2018)
      Some 1500 years ago, on a gravel spit extending into the Chukchi Sea, people living at the site of Ipiutak buried several members of their community.
    • Dissolved organic matter in wetland soils and streams of Southeast Alaska: Source, Concentration, and Chemical Quality

      Fellman, Jason B.; Hood, Eran; Boone, Rich; Jones, Jeremy; White, Dan; D'Amore, David (2008-12)
      Dissolved organic matter (DOM) transported from terrestrial to aquatic ecosystems is an important source of C, N and energy for the metabolism of aquatic heterotrophic bacteria. I examined the concentration and chemical quality of DOM exported from coastal temperate watersheds in southeast Alaska to determine if wetland soils are an important source of biodegradable dissolved organic carbon (BDOC) to aquatic ecosystems. I addressed this question through a combination of high resolution temporal and spatial field measurements in three watersheds near Juneau, Alaska by using a replicated experimental design that characterized DOM export from three different soil types (bog, forested wetland and upland forest) within each of the watersheds. PARAFAC modeling of fluorescence excitation-emission spectroscopy and BDOC incubations were used to evaluate the chemical quality and lability of DOM. Overall, my findings show that wetland soils contribute substantial biodegradable DOM to streams and the response in BDOC delivery to streams changes seasonally, with soil type, and during episodic events such as stormflows. In particular, the chemical quality of DOM in streamwater and soil solution was similar during the spring runoff and fall wet season, as demonstrated by the similar contribution of protein-like fluorescence in soil solution and in streams. These findings indicate a tight coupling between wetland DOM source pools and streams is responsible for the export of BDOC from terrestrial ecosystems. Thus, seasonal changes in soil-stream linkages can have a major influence on watershed biogeochemistry with important implications for stream metabolism and the delivery of labile DOM to coastal ecosystems. Soil DOM additions in small streams draining the three soil types showed that DOM leached from watershed soils is readily used as a substrate by stream heterotrophs and at the same time modified in composition by the selective degradation of the proteinaceous fraction of DOM. These findings indicate terrestrial DOM inputs to streams are an important source of C to support stream heterotrophic production. Thus, the production of protein-rich, labile DOM and subsequent loss in stream runoff has the potential to be an important loss of C and N from coastal temperate watersheds.
    • A foundation of ecology rediscovered: 100 years of succession on the William S. Cooper plots in Glacier Bay, Alaska

      Buma, Brian; Bisbing, Sarah; Krapek, John; Wright, Glenn (Ecological Society of America, 2017-03-24)
      Understanding plant community succession is one of the original pursuits of ecology, forming some of the earliest theoretical frameworks in the field. Much of this was built on the long-term research of William S. Cooper, who established a permanent plot network in Glacier Bay, Alaska, in 1916. This study now represents the longest-running primary succession plot network in the world. Permanent plots are useful for their ability to follow mechanistic change through time without assumptions inherent in space-for-time (chronosequence) designs. After 100-yr, these plots show surprising variety in species composition, soil characteristics (carbon, nitrogen, depth), and percent cover, attributable to variation in initial vegetation establishment first noted by Cooper in the 1916–1923 time period, partially driven by dispersal limitations. There has been almost a complete community composition replacement over the century and general species richness increase, but the effective number of species has declined significantly due to dominance of Salix species which established 100-yr prior (the only remaining species from the original cohort). Where Salix dominates, there is no establishment of “later” successional species like Picea. Plots nearer the entrance to Glacier Bay, and thus closer to potential seed sources after the most recent glaciation, have had consistently higher species richness for 100 yr. Age of plots is the best predictor of soil N content and C:N ratio, though plots still dominated by Salix had lower overall N; soil accumulation was more associated with dominant species. This highlights the importance of contingency and dispersal in community development. The 100-yr record of these plots, including species composition, spatial relationships, cover, and observed interactions between species provides a powerful view of long-term primary succession.
    • MABEL photon-counting laser altimetry data in Alaska for ICESat-2 simulations and development

      Brunt, Kelly M.; Neumann, Thomas A.; Amundson, Jason M.; Kavanaugh, Jeffrey L.; Moussavi, Mahsa S.; Walsh, Kaitlin M.; Cook, William B.; Markus, Thorsten (Copernicus Publications on behalf of the European Geosciences Union, 2016-08-10)
      Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) is scheduled to launch in late 2017 and will carry the Advanced Topographic Laser Altimeter System (ATLAS) which is a photon-counting laser altimeter and represents a new approach to satellite determination of surface elevation. Given the new technology of ATLAS, an airborne instrument, the Multiple Altimeter Beam Experimental Lidar (MABEL), was developed to provide data needed for satellite-algorithm development and ICESat-2 error analysis. MABEL was deployed out of Fairbanks, Alaska, in July 2014 to provide a test dataset for algorithm development in summer conditions with water-saturated snow and ice surfaces. Here we compare MABEL lidar data to in situ observations in Southeast Alaska to assess instrument performance in summer conditions and in the presence of glacier surface melt ponds and a wet snowpack. Results indicate the following: (1) based on MABEL and in situ data comparisons, the ATLAS 90m beam-spacing strategy will provide a valid assessment of across-track slope that is consistent with shallow slopes (< 1) of an ice-sheet interior over 50 to 150m length scales; (2) the dense along-track sampling strategy of photon counting systems can provide crevasse detail; and (3) MABEL 532 nm wavelength light may sample both the surface and subsurface of shallow (approximately 2m deep) supraglacial melt ponds. The data associated with crevasses and melt ponds indicate the potential ICESat-2 will have for the study of mountain and other small glaciers.
    • Raven’s Work in Tlingit Ethno-geography

      Thornton, Thomas F.; Deur, Douglas; Adams, Bert (University of Hawaii Press, 2019-01-01)
    • Summary of Reported Whale-Vessel Collisions in Alaskan Waters

      Neilson, Janet L.; Gabriele, Christine M.; Jensen, Aleria S.; Jackson, Kaili; Straley, Janice M. (Hindawi Publishing Corporation, 2012-03-26)
      Here we summarize 108 reported whale-vessel collisions in Alaska from 1978–2011, of which 25 are known to have resulted in the whale's death. We found 89 definite and 19 possible/probable strikes based on standard criteria we created for this study. Most strikes involved humpback whales (86%) with six other species documented. Small vessel strikes were most common (<15 m, 60%), but medium (15–79 m, 27%) and large (≥80 m, 13%) vessels also struck whales. Among the 25 mortalities, vessel length was known in seven cases (190–294 m) and vessel speed was known in three cases (12–19 kn). In 36 cases, human injury or property damage resulted from the collision, and at least 15 people were thrown into the water. In 15 cases humpback whales struck anchored or drifting vessels, suggesting the whales did not detect the vessels. Documenting collisions in Alaska will remain challenging due to remoteness and resource limitations. For a better understanding of the factors contributing to lethal collisions, we recommend (1) systematic documentation of collisions, including vessel size and speed; (2) greater efforts to necropsy stranded whales; (3) using experienced teams focused on determining cause of death; (4) using standard criteria for validating collision reports, such as those presented in this paper.