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Three regression models were developed for describing variability of host-specific flux data in eight Great Lakes tributaries. Models include one for Lachnospiraceae flux, one for human bacteroides flux, and one for ruminant bacteroides flux. Models were developed using the R project for statistical computing with core functionality and the survival, smwrBase, and smwrQW packages. Predictor variables for these models are included in the data file and input files provided. These include sampling dates and times, rainfall depth, percent of watershed underlain by tile drainage, cattle population (for the ruminant marker model) and human population (for the human marker models). Sample collection and laboratory analyses...
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Watersheds draining the Arctic Coastal Plain (ACP) of Alaska are dominated by permafrostand snowmelt runoff that create abundant surface storage in the form of lakes, wetlands, and beaded streams. These surface water elements compose complex drainage networks that affect aquatic ecosystem connectivity and hydrologic behavior. The 4676 km2 Fishand Creek drainage basin is composed of three watersheds that represent a gradient of theACP landscape with varying extents of eolian, lacustrine, and fluvial landforms. In each watershed, we analyzed 2.5-m-resolution aerial photography, a 5-m digital elevationmodel, and river gauging and climate records to better understand ACP watershed structureand processes. We show that...
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The Yukon North Slope is an arctic “hot spot” of climate change-induced effects with profound significance for the Inuvialuit and the larger region. In 1984, the Inuvialuit entered into a land claim agreement – the Inuvialuit Final Agreement (IFA) – with the governments of Canada, Yukon and Northwest Territories. A co-management body formed to make a plan, which was developed in 2003 but never ratified and is now considered out-of-date. Round River Conservation Studies is assisting WMAC(NS) in the collection, development and synthesis of spatial data, models and analyses of cultural and ecological values of the YNS.The project is a collaboration among the NWB LCC, Round River Conservation Studies, and the Arctic...
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Arctic grayling (Thymallus arcticus) have a life-history strategy specifically adapted to the extreme climate of the North. These fish migrate to spawning grounds just after breakup in the spring, then migrate to feeding sites in early summer, and finally in the fall migrate back to their overwintering sites. The Kuparuk River is a perennial stream originating in the northern foothills of the Brooks Range on the North Slope of Alaska. Sections of the Kuparuk are periodically intermittent in that, during low flows in the system, these channel reaches appear dry. The flow varies between surface and subsurface in this permafrost-dominated environment, with subsurface flow being limited to the unfrozen thaw bulb around...
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This part of DS 781 presents data for the isopachs for the Point Conception to Hueneme Canyon, California, region. The vector data file is included in "Isopachs_PointConceptionToHuenemeCanyon.zip," which is accessible from https://doi.org/10.5066/F7891424. As part of the USGS's California State Waters Mapping Project, a 50-m grid of sediment thickness for the seafloor within the 3-nautical mile limit between Point Conception and Hueneme Canyon was generated from seismic-reflection data collected in 2014 (USGS activity 2014-632-FA) supplemented with outcrop and geologic structure (fault) information following the methodology of Wong (2012). This sediment thickness layer was merged with a previously published sediment...
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This part of DS 781 presents data for the transgressive contours for the Point Conception to Hueneme Canyon, California, region. The vector file is included in "TransgressiveContours_PointConceptionToHuenemeCanyon.zip," which is accessible from http://dx.doi.org/10.5066/F7891424. As part of the USGS's California State Waters Mapping Project, a 50-m grid of sediment thickness for the seafloor within the 3-nautical mile limit between Point Conception and Hueneme Canyon was generated from seismic-reflection data collected in 2014 (USGS activity 2014-632-FA) supplemented with outcrop and geologic structure (fault) information following the methodology of Wong (2012). Water depths determined from bathymetry data were...
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Floods, spatially complex water flows, and organism movements all generate important fluxes of aquatic-derived materials into terrestrial habitats, counteracting the gravity-driven downhill transport of matter from terrestrial-to-aquatic ecosystems. The magnitude of these aquatic subsidies isoften smaller than terrestrial subsidies to aquatic ecosystems but higher in nutritional quality, energy density, and nutrient concentration. The lateral extent of biological aquatic subsidies is typically small, extending only a few meters into riparian habitat; however, terrestrial consumers often aggregate on shorelines to capitalize on these high-quality resources. Although the ecological effects of aquatic subsidies remain...
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How local geomorphic and hydrologic features mediate the sensitivity of stream thermal regimes to variation in climatic conditions remains a critical uncertainty in understanding aquatic ecosystem responses to climate change. We used stable isotopes of hydrogen and oxygen to estimate contributions of snow and rainfall to 80 boreal streams and show that differences in snow contribution are controlled by watershed topography. Time series analysis of stream thermal regimes revealed that streams in rain-dominated, low-elevation watersheds were 5–8 times more sensitive to variation in summer air temperature compared to streams draining steeper topography whose flows were dominated by snowmelt. This effect was more pronounced...
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There is a great deal of interest in whether and how Alaska’s precipitation is changing but little agreement in the existing peer-reviewed literature. To provide insight on this question, we have selected three commonly used 0.5° resolution gridded precipitation products that have long-term monthly data coverage (Climatic Research Unit TS3.10.1, Global Precipitation Climatology Centre Full Data Reanalysis version 5, and University of Delaware version 2.01) and evaluated their homogeneity and trends with multiple methods over two periods, 1950–2008 and 1980–2008. All three data sets displayed common broadscale features of Alaska’s precipitation climatology, but there were substantial differences between them in terms...
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This dataset is a component of a complete package of products from the Connect the Connecticut project. Connect the Connecticut is a collaborative effort to identify shared priorities for conserving the Connecticut River Watershed for future generations, considering the value of fish and wildlife species and the natural ecosystems they inhabit. Click here to download the full data package, including all documentation.This dataset represents the climate response index for Northern Waterthrush. Climate response is one of several different measures of landscape capability that reflect different decisions (or assumptions) regarding how to incorporate current versus future land use and climate changes. The climate response...
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This dataset contains data supporting the paper: DeCrappeo, N.M., DeLorenze, E.J., Giguere, A.T., Pyke, D.A., and Bottomley, P.J. Fungal and bacterial contributions to nitrogen cycling in cheatgrass-invaded and uninvaded native sagebrush soils of the western USA (accepted at the journal Plant and Soil). The purpose of the study was to evaluate the relative contributions of soil bacteria and fungi to inorganic nitrogen (N) cycling in sagebrush and cheatgrass-invaded soils using a 15N isotope dilution experiment. Soils were collected from sagebrush and cheatgrass rhizospheres at six paired sites in southwest Idaho and southeast Oregon. In order to partition the contribution of each microbial group to N cycling, soils...
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Interactions and feedbacks between abundant surface waters and permafrost fundamentally shapelowland Arctic landscapes. Sublake permafrost is maintained when the maximum ice thickness (MIT) exceedslake depth and mean annual bed temperatures (MABTs) remain below freezing. However, decliningMIT since the1970s is likely causing talik development below shallow lakes. Here we show high-temperature sensitivity towinter ice growth at the water-sediment interface of shallow lakes based on year-round lake sensor data.Empirical model experiments suggest that shallow (1m depth) lakes have warmed substantially over the last30years (2.4°C), withMABT above freezing5 of the last 7years.This is incomparison to slower ratesofwarming...
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In this first worldwide synthesis of in situ and satellite-derived lake data, we find that lakesummer surface water temperatures rose rapidly (global mean = 0.34°C decade1) between 1985 and2009. Our analyses show that surface water warming rates are dependent on combinations of climate andlocal characteristics, rather than just lake location, leading to the counterintuitive result that regionalconsistency in lake warming is the exception, rather than the rule. The most rapidly warming lakes are widelygeographically distributed, and their warming is associated with interactions among different climatic factors—from seasonally ice-covered lakes in areas where temperature and solar radiation are increasing whilecloud...
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection. This framework is underpinned by the concept that tundra ecosystem productivity is ultimately driven by the thermodynamics of the system induced by climate.
Categories: Data, Publication; Types: Citation; Tags: ALPINE/TUNDRA, ALPINE/TUNDRA, CARBON, CARBON, CARBON CYCLE/CARBON BUDGET MODELS, All tags...
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The Arctic Coastal Plain (ACP) of Alaska is an important region for millions of migrating and nesting shorebirds. However, this region is threatened by climate change and increased human development (e.g., oil and gas production) that have the potential to greatly impact shorebird populations and breeding habitat in the near future. Because historic data on shorebird distributions in the ACP are very coarse and incomplete, we sought to develop detailed, contemporary distribution maps so that the potential impacts of climate-mediated changes and development could be ascertained. To do this, we developed and mapped habitat suitability indices for eight species of shorebirds (Black-bellied Plover [Pluvialis squatarola],...
An integrated high resolution tide and storm surge model has been developedfor all of coastal Alaska. The model uses the ADCIRC basin-to-channelscale unstructured grid circulation code. Tidal forcing from global tidal modelsand meteorological forcing from the Climate Forecast System Reanalysisare used. The model’s tidal solution has been validated at 121 shelf andnearshore stations. The model’s skill has been investigated for summer, falland winter storms. Sea ice has been incorporated through a parameterizedwind drag coefficient which modifies the air-sea drag under ice coverage.Three large storms with distinctly different ice coverages were chosen to exhibitthe effect of sea ice on the resulting storm surge. The...
The Adapt Alaska Collaborative grew out of a set of initiatives to promote climate resilience and adaptation in Alaska. On May 24 and 25, 2017 a group of participants (including representatives of Alaska regional, state and federal agencies and organizations) gathered at a work session to identify next steps to build on the momentum generated by these initiatives toward a more resilient Alaska. At the work session, three working groups formed around specific areas of effort, including a Planning Working Group with the task of identifying ways to streamline the many planning requirements associated with implementing climate resilience and adaptation strategies.The Adapt Alaska Planning Working Group looked at a range...
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This is a 30-meter grid that maps upland and wetland wildlife habitats/ecological systems for the Northeastern US, including all 13 states from Maine to Virginia, west to New York, Pennsylvania and West Virginia, and for the Maritime provinces of Canada (Nova Scotia, Prince Edward Island, and New Brunswick) and southeastern Quebec. Mapped habitat types are drawn from the Northeastern Terrestrial Habitat Classification System (NETHCS) and from some ecological system types identifed by Canadian ecologists as being unique to Canada. The NETHCS is based on NatureServe’s Ecological Systems Classification, augmented with additional information from individual state wildlife classifications and other information specific...
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Many Arctic shorebird populations are declining, and quantifying adult survival and the effects of anthropogenic factorsis a crucial step toward a better understanding of population dynamics. We used a recently developed, spatially explicitCormack–Jolly–Seber model in a Bayesian framework to obtain broad-scale estimates of true annual survival rates for 6species of shorebirds at 9 breeding sites across the North American Arctic in 2010–2014. We tested for effects ofenvironmental and ecological variables, study site, nest fate, and sex on annual survival rates of each species in thespatially explicit framework, which allowed us to distinguish between effects of variables on site fidelity versus truesurvival. Our...
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The Arctic Coastal Plain (ACP) of northern Alaskaconsists of an extremely low gradient, lake-richlandscape that is characterized by a complex networkof aquatic habitats and surface features stronglyinfluenced by permafrost dynamics. Much is unknownabout the form, function, and ecological conditions inthis unique hydrologic setting. Amplified climatechange and landscape responses in the Arctic furthercomplicate the capacity to separate natural variabilityfrom land use effects that may occur with petroleumdevelopment. A comprehensive, multi-disciplinaryreview and analysis of recent studies and initialinventory and monitoring in the Fish Creek watershedon the ACP provided guidance to develop a frameworkfor future aquatic...


map background search result map search result map Canada-US Terrestrial Habitat Map Climate Response for Northern Waterthrush, 2080, CT River Watershed Isopachs--Point Conception to Hueneme Canyon, California Transgressive Contours--Point Conception to Hueneme Canyon, California Regression models and associated data for describing variability of host specific bacteria fluxes in eight Great Lakes tributaries, 2011-2013 Nitrogen cycling rates from sagebrush and cheatgrass-invaded soils in the Northern Great Basin (2008) Linking North Slope of Alaska climate, hydrology, and fish migration Environmental and ecological conditions at Arctic breeding sites have limited effects on true survival rates of adult shorebirds Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate Reconciling precipitation trends in Alaska: 2. Gridded data analyses Rapid and highly variable warming of lake surface waters around the globe Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature Subsidies of Aquatic Resources in Terrestrial Ecosystems Predicting breeding shorebird distributions on the Arctic Coastal Plain of Alaska Drainage Network Structure and Hydrologic Behavior of Three Lake-Rich Watersheds on the Arctic Coastal Plain, Alaska Developing a Long-term Aquatic Monitoring Network Developing a Long-Term Aquatic Monitoring Network in a Complex Watershed of the Alaskan Arctic Coast Yukon North Slope Wildlife Management Plan Linking North Slope of Alaska climate, hydrology, and fish migration Isopachs--Point Conception to Hueneme Canyon, California Transgressive Contours--Point Conception to Hueneme Canyon, California Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate Drainage Network Structure and Hydrologic Behavior of Three Lake-Rich Watersheds on the Arctic Coastal Plain, Alaska Developing a Long-term Aquatic Monitoring Network Developing a Long-Term Aquatic Monitoring Network in a Complex Watershed of the Alaskan Arctic Coast Nitrogen cycling rates from sagebrush and cheatgrass-invaded soils in the Northern Great Basin (2008) Rapid and highly variable warming of lake surface waters around the globe Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature Subsidies of Aquatic Resources in Terrestrial Ecosystems Climate Response for Northern Waterthrush, 2080, CT River Watershed Yukon North Slope Wildlife Management Plan Regression models and associated data for describing variability of host specific bacteria fluxes in eight Great Lakes tributaries, 2011-2013 Predicting breeding shorebird distributions on the Arctic Coastal Plain of Alaska Canada-US Terrestrial Habitat Map Reconciling precipitation trends in Alaska: 2. Gridded data analyses Environmental and ecological conditions at Arctic breeding sites have limited effects on true survival rates of adult shorebirds