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This soil survey is a publication of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and the United States Department of the Interior. The Natural Resources Conservation Service has leadership for the Federal part of the National Cooperative Soil Survey. Major fieldwork for this soil survey was completed in 2002. Soil names and descriptions were approved in 2003. Unless otherwise indicated, statements in this publication refer to conditions in the survey area in 2002. This survey was made cooperatively by the Natural Resources Conservation Service, the University of Alaska Fairbanks Agricultural and Forestry Experiment Station, and the National Park Service.
North-western Canada and eastern Alaska are recognised as having one of the oldest known continental glacial records (Late Pliocene) preserved in stratigraphical sections. These include the individual and complex records of Cordilleran, montane and continental glaciations. Regional scale glaciations (Cordilleran and continental) started in northwestern Canada and east-central Alaska between 2.9 and 2.6 million years ago. Overall, two Cordilleran glaciations and two plateau ice caps (Horton Ice Cap) developed in Late Pliocene (Gauss and Matuyama Chron). During the Early Pleistocene, three Cordilleran glaciations occurred, while one to five continental glaciations (Keewatin Ice Sheet and Horton Ice Cap) are inferred...
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SOC in northern high latitudes is highly vulnerable to disturbances Disturbances are an important component of the northern soil C cycle Soils in northern high latitudes could loose their long-term C sink character This synthesis addresses the vulnerability of the North American high-latitude soil organic carbon (SOC) pool to climate change. Disturbances caused by climate warming in arctic, subarctic, and boreal environments can result in significant redistribution of C among major reservoirs with potential global impacts. We divide the current northern high-latitude SOC pools into (1) near-surface soils where SOC is affected by seasonal freeze-thaw processes and changes in moisture status, and (2) deeper permafrost...
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The extensive boreal biome is little studies relative to its global importance. Its high soil moisture and low temperatures result in large below-ground reservoirs of carbon (C) and nitrogen (N). Presently, such high-latitude ecosystems are undergoing the largest temperature increases in global warming. Change in soil temperature or moisture in the large pools of soil organic matter could fundamentally change ecosystem C and N budgets. Since 1990, we have conducted treeline studies in a small (800 ha) watershed in Noatak National Preserve, northwestern Alaska. Our objectives were to (1) gain an understanding of treeline dynamics, structure, and function; and (2) examine the effects of global climate change, particularly...
SOC in northern high latitudes is highly vulnerable to disturbances Disturbances are an important component of the northern soil C cycle Soils in northern high latitudes could loose their long-term C sink character This synthesis addresses the vulnerability of the North American high-latitude soil organic carbon (SOC) pool to climate change. Disturbances caused by climate warming in arctic, subarctic, and boreal environments can result in significant redistribution of C among major reservoirs with potential global impacts. We divide the current northern high-latitude SOC pools into (1) near-surface soils where SOC is affected by seasonal freeze-thaw processes and changes in moisture status, and (2) deeper permafrost...
Northern peatlands provide important global and regional ecosystem services (carbon storage, water storage, and biodiversity). However, these ecosystems face increases in the severity, areal extent, and frequency of climate-mediated (e.g., wildfire, drought) and land-use change (e.g., drainage, flooding, and mining) disturbances that are placing the future security of these critical ecosystem services in doubt. Here we provide the first detailed synthesis of autogenic hydrological feedbacks that operate within northern peatlands to regulate their response to changes in seasonal water deficit and varying disturbances. We review, synthesize, and critique the current process-based understanding and qualitatively assess...
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Frost heaving is ubiquitous throughout cold regions, causing damage to building foundations, roads, airfields, railways, utilities, and pipelines. Out of the voluminous body of research conducted over the last 80 years, few studies investigated the mineral surface effects on frost heaving. These previous studies were conducted nearly 50 years ago with rudimentary equipment and on homogeneous and artificial soils that have limited applicability to actual field conditions. The purpose of the research presented here is to investigate the adsorbed cation effects on the frost susceptibility of natural soils through experimental testing. A comprehensive suite of laboratory experiments was conducted on five natural heterogeneous...
Northern peatlands provide important global and regional ecosystem services (carbon storage, water storage, and biodiversity). However, these ecosystems face increases in the severity, areal extent, and frequency of climate-mediated (e.g., wildfire, drought) and land-use change (e.g., drainage, flooding, and mining) disturbances that are placing the future security of these critical ecosystem services in doubt. Here we provide the first detailed synthesis of autogenic hydrological feedbacks that operate within northern peatlands to regulate their response to changes in seasonal water deficit and varying disturbances. We review, synthesize, and critique the current process-based understanding and qualitatively assess...
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Since the mid 1970s, Interior Alaska white spruce trees experienced markedly lower growth than during the 19th and early 20th centuries. This observation raises the question of forest persistence on certain sites of lowland central and eastern Alaska. We analyzed white spruce growth across a 36-site network (540 trees) on three major river floodplains in boreal Alaska along a longitudinal gradient from eastern Interior to the southwest tree limit to test for the presence of tree growth patterns and climate sensitivities. Chronologies are compared for temperature sensitivity at both stand and individual tree levels, using data from Bethel, McGrath, and Fairbanks NWS stations during the common period of 1952–2001....


map background search result map search result map Spatial coherence and change of opposite white spruce temperature sensitivities on floodplains in Alaska confirms early-stage boreal biome shift Land cover disturbances and feedbacks to the climate system in Canada and Alaska Treeline biogeochemistry and dynamics, Noatak National Preserve, northwestern Alaska Vulnerability of high-latitude soil organic carbon in North America to disturbance The record of Glacial Lake Champagne in Kusawa Lake, southwestern Yukon Territory Experimental study of adsorbed cation effects on the frost susceptibility of natural soils Responses of boreal fire regimes to climatic and land-cover changes: Perspectives from multiple spatiotemporal scales The record of Glacial Lake Champagne in Kusawa Lake, southwestern Yukon Territory Responses of boreal fire regimes to climatic and land-cover changes: Perspectives from multiple spatiotemporal scales Treeline biogeochemistry and dynamics, Noatak National Preserve, northwestern Alaska Experimental study of adsorbed cation effects on the frost susceptibility of natural soils Spatial coherence and change of opposite white spruce temperature sensitivities on floodplains in Alaska confirms early-stage boreal biome shift Land cover disturbances and feedbacks to the climate system in Canada and Alaska Vulnerability of high-latitude soil organic carbon in North America to disturbance