Fairbanks, AK, United States
Fairbanks, AK, United States

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Ping C.-L.,University of Alaska Fairbanks | Michaelson G.J.,University of Alaska Fairbanks | Guo L.,University of Southern Mississippi | Jorgenson M.T.,ABR Inc. | And 4 more authors.
Journal of Geophysical Research: Biogeosciences | Year: 2011

Carbon, nitrogen, and material fluxes were quantified at 48 sampling locations along the 1957 km coastline of the Beaufort Sea, Alaska. Landform characteristics, soil stratigraphy, cryogenic features, and ice contents were determined for each site. Erosion rates for the sites were quantified using satellite images and aerial photos, and the rates averaged across the coastline increased from 0.6 m yr-1 during circa 1950-1980 to 1.2 m yr -1 during circa 1980-2000. Soils were highly cryoturbated, and organic carbon (OC) stores ranged from 13 to 162 kg OC m-2 in banks above sea level and averaged 63 kg OC m-2 over the entire coastline. Long-term (1950-2000) annual lateral fluxes due to erosion were estimated at -153 Gg OC, -7762 Mg total nitrogen, -2106 Tg solids, and -2762 Tg water. Total land area loss along the Alaska Beaufort Sea coastline was estimated at 203 ha yr-1. We found coastal erosion rates, bank heights, soil properties, and material stores and fluxes to be extremely variable among sampling sites. In comparing two classification systems used to classifying coastline types from an oceanographic, coastal morphology perspective and geomorphic units from a terrestrial, soils perspective, we found both systems were effective at differentiating significant differences among classes for most material stores, but the coastline classification did not find significant differences in erosion rates because it lacked differentiation of soil texture. Copyright © 2011 by the American Geophysical Union.


Garshelis D.L.,University of Minnesota | Johnson C.B.,ABR Inc.
Marine Pollution Bulletin | Year: 2013

Sea otters (Enhydra lutris) suffered major mortality after the Exxon Valdez oil spill in Prince William Sound, Alaska, 1989. We evaluate the contention that their recovery spanned over two decades. A model based on the otter age-at-death distribution suggested a large, spill-related population sink, but this has never been found, and other model predictions failed to match empirical data. Studies focused on a previously-oiled area where otter numbers (~80) stagnated post-spill; nevertheless, post-spill abundance exceeded the most recent pre-spill count, and population trends paralleled an adjacent, unoiled-lightly-oiled area. Some investigators posited that otters suffered chronic effects by digging up buried oil residues while foraging, but an ecological risk assessment indicated that exposure levels via this pathway were well below thresholds for toxicological effects. Significant confounding factors, including killer whale predation, subsistence harvests, human disturbances, and environmental regime shifts made it impossible to judge recovery at such a small scale. © 2013 Elsevier Ltd.


Nelson P.R.,Denali National Park and Preserve | Nelson P.R.,Oregon State University | Roland C.,Denali National Park and Preserve | Macander M.J.,ABR Inc. | McCune B.,Oregon State University
Remote Sensing of Environment | Year: 2013

Spatial variation of available food resources can be difficult to accurately quantify for wide ranging organisms at landscape scales. Lichens with usnic acid, a yellowish pigment, constitute a large portion of caribou winter diet across much of their range. We take a new approach of modeling lichen abundances by capitalizing on unique spectral characteristics of usnic acid lichens. We utilize a recently completed ground reference vegetation data set extending over 12,000km2 in Denali National Park and Preserve, Alaska to model the abundance of usnic lichen and other forage vegetation groups. Spectral signatures were obtained for more than 700 vegetation monitoring plots in Denali from Landsat 7 ETM+ imagery. We fit models of the absolute percent cover of vegetation groups corresponding to caribou diet items, with a focus on lichens. We used non-parametric multiplicative regression to capture the non-linear relationships between vegetation cover and spectral and environmental data. Different groupings of lichen cover were tried as response variables in addition to usnic lichens to see if other lichen color groups were more detectable. The best fitting lichen model was for usnic acid lichens, which explained 37% of the variation using only three predictors (elevation, bands 1 and 7). Elevation had a non-linear, double-humped shaped relationship to usnic lichen abundance while bands 1 and 7 were positively correlated with usnic lichen cover. These results support previous spectroradiometric ground measurements that indicated usnic lichens were distinctive at those wavelengths. Other vegetation groups had models that explained between 31% and 51% of the variation in cover. Maps of estimated abundance of usnic lichens and other vegetation groups covering the northern half of Denali were generated using our models. These maps enable the study of the role of food resources as a continuous resource in winter habitat selection by caribou, rather than assuming food as a coarser, categorical or thematic variable assigned to discrete areas of the landscape as has been done in most previous studies. © 2013 Elsevier Inc.


Arp C.D.,U.S. Geological Survey | Jones B.M.,U.S. Geological Survey | Schmutz J.A.,U.S. Geological Survey | Urban F.E.,U.S. Geological Survey | Jorgenson M.T.,ABR Inc.
Polar Biology | Year: 2010

Arctic habitats at the interface between land and sea are particularly vulnerable to climate change. The northern Teshekpuk Lake Special Area (N-TLSA), a coastal plain ecosystem along the Beaufort Sea in northern Alaska, provides habitat for migratory waterbirds, caribou, and potentially, denning polar bears. The 60-km coastline of N-TLSA is experiencing increasing rates of coastline erosion and storm surge flooding far inland resulting in lake drainage and conversion of freshwater lakes to estuaries. These physical mechanisms are affecting upland tundra as well. To better understand how these processes are affecting habitat, we analyzed long-term observational records coupled with recent short-term monitoring. Nearly the entire coastline has accelerating rates of erosion ranging from 6 m/year from 1955 to 1979 and most recently peaking at 17 m/year from 2007 to 2009, yet an intensive monitoring site along a higher bluff (3-6 masl) suggested high interannual variability. The frequency and magnitude of storm events appears to be increasing along this coastline and these patterns correspond to a greater number of lake tapping and flooding events since 2000. For the entire N-TLSA, we estimate that 6% of the landscape consists of salt-burned tundra, while 41% is prone to storm surge flooding. This offset may indicate the relative frequency of low-magnitude flood events along the coastal fringe. Monitoring of coastline lakes confirms that moderate westerly storms create extensive flooding, while easterly storms have negligible effects on lakes and low-lying tundra. This study of two interacting physical mechanisms, coastal erosion and storm surge flooding, provides an important example of the complexities and data needs for predicting habitat change and biological responses along Arctic land-ocean interfaces. © 2010 The Author(s).


Trademark
Grower's Secret and Abr Llc | Date: 2011-01-18

Organic fertilizers; organic growing media produced from fermented edible organic mushrooms for use as a plant growth accelerant, growth stimulant and growth energizer.


Trademark
Grower's Secret and Abr Llc | Date: 2010-02-24

Fertilizers; organic growing media produced from fermented edible mushrooms for use as a plant growth accelerant, growth stimulant and growth energizer.


Trademark
Grower's Secret and Abr Llc | Date: 2011-06-28

Fertilizers; organic growing media produced from fermented edible mushrooms for use as a plant growth accelerant, growth stimulant and growth energizer.


Trademark
Abr Llc | Date: 2011-07-05

Fertilizers; organic growing media produced from fermented edible mushrooms for use as a plant growth accelerant, growth stimulant and growth energizer.


Trademark
Grower's Secret and Abr Llc | Date: 2010-02-24

Fertilizers; organic growing media produced from fermented edible mushrooms for use as a plant growth accelerant, growth stimulant and growth energizer.


Michaelson G.J.,University of Alaska Fairbanks | Ping C.L.,University of Alaska Fairbanks | Jorgenson M.T.,ABR Inc.
Journal of Geophysical Research: Biogeosciences | Year: 2011

Soil CH4 and CO2 gas contents were determined at 39 sites located along the 1957 km coastline of the Beaufort Sea of northern Alaska. Average soil CH4 concentrations increased with depth into the upper frozen layers, while the CO2 decreased with depth. Over 80% of the CH4 and 46% of the total CO2 were contained in the permafrost portion of the profiles. Overall, average concentrations of CH 4 within the soil profiles were correlated to water content (R 2 = 0.66, p ≤ 0.01). Concentrations of CO2 were correlated to total organic carbon (R2 = 0.76, p ≤ 0.001) and negatively correlated to water content (R2 = 0.61, p ≤ 0.01). The highest total bank gas concentrations for both gases were found in ice-rich permafrost (average volumetric H2O ≥ 70%). Soils eroded across the coast annually were estimated to contain 3.61 ± 1.35 t CH4 (average 1.86 ± 0.70 g m-2) and 469 ± 128 t CO 2 (average 240 ± 65 g m-2). Gas amounts present in annually eroding banks were on the same order of magnitude as amounts emitted per year on an area basis from undisturbed tundra and lakes reported by others for the Arctic and smaller than previous estimates for local coastal anthropogenic sources. Soil stocks of gases, water and total organic carbon indicate that with coastal permafrost degradation gas release is minor in magnitude and importance to C-dynamics when compared to the TOC stocks of the coastline. Copyright 2011 by the American Geophysical Union.

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