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Southwest Alaska is one of the fastest warming regions on Earth and its aquatic resources are at distinct risk from changing climate. Previous work has demonstrated that a variety of physical and biological processes are sensitive to changing climate regimes in this region, including those that support wildlife and fisheries that are of substantial importance for subsistence and commercial activities. This collaborative project resulted in the compilation of a database of existing stream, river and lake temperatures that is unmatched anywhere else in Alaska in terms of its spatial and temporal coverage. Analysis of these data resulted in refinement of the monitoring plan developed to characterize thermal responses...
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In Arctic ecosystems, freshwater fish migrateseasonally between productive shallow water habitatsthat freeze in winter and deep overwinter refuge in riversand lakes. How these movements relate to seasonal hydrologyis not well understood.We used passive integratedtransponder tags and stream wide antennae to track1035 Arctic grayling in Crea Creek, a seasonally flowingbeaded stream on the Arctic Coastal Plain, Alaska. Migrationof juvenile and adult fish into Crea Creek peakedin June immediately after ice break-up in the stream. Fishthat entered the stream during periods of high flow andcold stream temperature traveled farther upstream thanthose entering during periods of lower flow and warmertemperature. We used generalized...
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Numerous studies utilizing remote sensing imagery and other methods have documented that thermokarst lakes are undergoing varied hydrological transitions in response to recent climate changes, from surface area expansion to drainage and evaporative desiccation. Here, we provide a synthesis of hydrological conditions for 376 lakes of mainly thermokarst origin across high-latitude North America. We assemble surface water isotope compositions measured during the past decade at five lake-rich landscapes including Arctic Coastal Plain (Alaska), Yukon Flats (Alaska), Old Crow Flats (Yukon), northwestern Hudson Bay Lowlands (Manitoba), and Nunavik (Quebec). These landscapes represent the broad range of thermokarst environments...
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Field measurements, satellite observations, and models document a thinning trend in seasonal Arcticlake ice growth, causing a shift from bedfast to floating ice conditions. September sea iceconcentrations in the Arctic Ocean since 1991 correlate well (r=+0.69, p<0.001) to this lakeregime shift. To understand how and to what extent sea ice affects lakes, we conducted modelexperiments to simulate winters with years of high (1991/92) and low (2007/08) sea ice extent forwhich we also had field measurements and satellite imagery characterizing lake ice conditions. Alakeice growth model forced with Weather Research and Forecasting model output produced a 7%decrease in lake ice growth when 2007/08 sea ice was imposed on...
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Kootenai river hydraulic conditions were simulated using the iRIC FaSTMECH two-dimensional hydraulic flow model (Nelson, 2003). In addition to this study, FaSTMECH 2D flow models have been developed for numerous Kootenai River studies dating back to 2005. The methods used to develop, calibrate, and simulate FaSTMECH 2D flow models are described at length in multiple previous studies (Fosness and Dudunake, in press; Barton and others, 2005; Barton and others, 2007; Logan and others, 2011; McDonald and others, 2016; McDonald and Nelson, 2018; McDonald and Nelson, 2020). Model simulations were combined with white sturgeon telemetry data to explain fish positions with respect to selected depths and depth-averaged velocity.
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Aquatic Biology, Bonners Ferry, Boundary, Ecology, Idaho, All tags...
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Hourly carbon dioxide (CO2) measurements from four locations of snowpack profiles with vertical spacing of 20 cm over seven winters (2010-2016) at the Glacier Lakes Ecosystem Experiments Site (GLEES) in southern Wyoming. All supporting data on snowpack properties (mostly modeled) are included to calculate hourly snowpack CO2 fluxes from raw data. In addition, turbulence from the adjacent AmeriFlux eddy covariance scaffold are included for statistical analyses. For comparison purposes, manual CO2 measurements collected at the site from 1998-1999 and 2004-2010 are also included. In addition to data, all scripts are provided to calculate fluxes and determine statistical effects of year, replicate and turbulence on...
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This data release includes tabular data files. The dataset consists of four input data tables (Appendices A1-A4) for a Lake Superior EcoPath with EcoSim (EwE; http://ecopath.org) model parameterized to the early 21st century using 2001-2016 collections. The data presented here are primarily intended to development a static ecosystem model representing a snapshot of Lake Superior circa 2005 when the bulk of information was collected. Input data were compiled from multiple federal, state, provincial, and tribal agencies, academic institutions, published reports, theses, and peer review journal articles. This dataset includes results from lake-wide Cooperative Science and Monitoring Initiative surveys (CSMI; CSMI 2020)...
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Lake polygons within the Fish Creek Watershed, Alaska were created and classified for a number of variables relevant to size, depth, hydrology, connectivity etc. Products derived from a 5m resolution IfSAR digital surface model by calculating a zero slope. Each feature was expanded by one pixel around the entire perimeter since all waterbodies were truncated by this during the slope calculation. Lakes >=1ha were manually extracted from the dataset and their perimeters further corrected using 2002 CIR orthophotography.
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service, Shapefile; Tags: AQUATIC ECOSYSTEMS, AQUATIC ECOSYSTEMS, Academics & scientific researchers, Arctic Landscape Conservation Cooperative data.gov, BIOSPHERE, All tags...
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Spawning migrations of Pacific salmon (Oncorhynchus spp.) to coastal watersheds provide a rich resource subsidy to freshwater consumers. However, variation in thermal regimes and spawning activity across the landscape constrain the ability of poikilothermic consumers to assimilate eggs and carcasses. We investigated how sockeye salmon (Oncorhynchus nerka) spawning density and stream temperature affect the growth, body condition, and fatty acid composition of juvenile coho salmon (Oncorhynchus kisutch), a known egg predator, in seven tributaries of the Wood River in Southwest Alaska. We compared mean body size of juvenile coho salmon in late summer among 3–7 years per stream and found that the largest mean size occurred...
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Natural cave passages penetrating coastal aquifers in the Yucatan Peninsula (Quintana Roo, Mexico) were accessed to investigate how regional meteorology and hydrology control dissolved organic carbon and methane dynamics in karst subterranean estuaries, the region of aquifers where fresh and saline waters mix. Three field trips were carried out in December 2013, August 2014, and January 2015 to obtain 1) physicochemical and 2) geochemical data from the water column and 3) temporal records of water chemistry and hydrological parameters below and above the surface at three sites within the Ox Bel Ha cave (Cenote Jailhouse, Cenote Naach Wennen Ha, and Cenote Odyssey) and another cave (Cenote Crustacea). These efforts...
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Datasets used to quantify and value the ecosystem service of sediment and nutrient retention for floodplains within the Difficult Run watershed located in Fairfax County, Virginia. Geospatial datasets include a digital elevation model (DEM), a hydrologically conditioned DEM, output from the USGS Stream Channel and Floodplain Metric Toolbox, and field data sets used to develop regression models to predict sediment and nutrient retention services for stream within the Difficult Run watershed.
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Bacteria were isolated from seeds of non-native Phragmites australis (haplotype M) then representatives were evaluated for their capacities to become intracellular in root cells, and their effects on: 1.) germination rates and seedling growth, 2.) susceptibility to damping-off disease, and 3.) mortality and growth of competitor plant seedlings (dandelion (Taraxacum officionale F. H. Wigg) and curly dock (Rumex crispus L.)). The experiments included the following assessments of Phragmites-associated bacteria (Pseudomonas spp, strains Sandy LB4 (Pseudomonas fluorescens) and West 9 (Pseudomonas sp.)): capacity for plant growth promotion (using Poa annua seeds), Poa annua and Phragmites australis seed germination and...
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The Fish Creek Watershed encompasses diverse aquatic habitats representative of much of the Arctic Coastal Plain of northern Alaska. Beyond surface water and permafrost responses caused by changes in climate, this landscape is also subject to potential land-use impacts related to petroleum development in the National Petroleum Reserve – Alaska (NPR-A). Thus, this region is an ideal setting to address aquatic habitat questions of longstanding interest to Arctic resource managers, scientists, and other stakeholders. Our multidisciplinary team is focusing on broad hypothesis that surface-water availability, connectivity, and temperature mediate aquatic habitats and trophic dynamics. We are working to understand and...
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These data are the result of a geospatial analysis involving multi-year SAR-based lake ice regime classification using sigma-naught backscatter intensity from calibrated space-borne C-band SAR for thousands of lakes in 7 lake districts in Alaska, USA, detailed in Engram et al., (in review). Historically, radar backscatter from space-borne and airborne platforms shows a lower backscatter return from bedfast lake ice and a higher backscatter return from floating ice (where liquid phase water exists under the ice) (Jeffries, Morris, Weeks, & Wakabayashi, 1994; Weeks, 1977). We used a threshold method where the threshold to differentiate floating and bedfast ice regimes was determined for each year from the frequency...
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Subterranean estuaries extend inland into density-stratified coastal carbonate aquifers that contain a surprising diversity of endemic animals (mostly crustaceans) within a highly oligotrophic environment. How complex ecosystems thrive in this globally-distributed, cryptic habitat (termed anchialine) is poorly understood. The northeastern margin of the Yucatan Peninsula contains over 250 km of mapped, diver-accessible caves passages where previous studies have suggested chemoautotrophic processes are the source of carbon and energy sustaining the anchialine food web. This dataset, collected during four field events during U.S. Geological Survey (USGS) Coastal and Marine Geology Program Field Activities 2015-013-FA...
map background search result map search result map Native and Invasive Species Plant Growth and Mortality in Growth Media Inoculated with Bacteria Found on Phragmites From New Jersey (2016) Geochemical data to characterize physical and chemical properties of the Cenote Bang, a component of the Ox Bel Ha cave network within the subterranean estuary coastal aquifer of the Yucatan Peninsula, from December 2013 to January 2016 Vertical snowpack CO2 profile measurements from 2010-2016 in a subalpine forest in southern Wyoming Difficult Run Floodplain Sediment and Nutrient Retention Ecosystem Service Datasets, Fairfax County, Virginia Fish CAFE Project Information Handout Arctic sea ice decline contributes to thinning lake ice trend in northern Alaska A synthesis of thermokarst lake water balance in high-latitude regions of North America from isotope tracers Thermal constraints on stream consumer responses to a marine resource subsidy Final Report Water Temperature Regimes in the Togiak NWR and Wood-Tikchik State Park Seasonal cues of Arctic grayling movement in a small Arctic stream: the importance of surface water connectivity Lake Ice Regime Classification Fish Creek Watershed Lake Classification White sturgeon fine-scale habitat model archive, Kootenai River near Bonners Ferry, Idaho, 2017 Compilation of Data for Parameterization of an Ecopath Model of Lake Superior at the Beginning of the 21st Century (2001-2016) Hydrological and chemical records from the flooded Ox Bel Ha cave system in the Yucatan Peninsula, Quintana Roo, from August 2014 to January 2015 Vertical snowpack CO2 profile measurements from 2010-2016 in a subalpine forest in southern Wyoming White sturgeon fine-scale habitat model archive, Kootenai River near Bonners Ferry, Idaho, 2017 Geochemical data to characterize physical and chemical properties of the Cenote Bang, a component of the Ox Bel Ha cave network within the subterranean estuary coastal aquifer of the Yucatan Peninsula, from December 2013 to January 2016 Difficult Run Floodplain Sediment and Nutrient Retention Ecosystem Service Datasets, Fairfax County, Virginia Hydrological and chemical records from the flooded Ox Bel Ha cave system in the Yucatan Peninsula, Quintana Roo, from August 2014 to January 2015 Fish CAFE Project Information Handout Arctic sea ice decline contributes to thinning lake ice trend in northern Alaska A synthesis of thermokarst lake water balance in high-latitude regions of North America from isotope tracers Seasonal cues of Arctic grayling movement in a small Arctic stream: the importance of surface water connectivity Fish Creek Watershed Lake Classification Native and Invasive Species Plant Growth and Mortality in Growth Media Inoculated with Bacteria Found on Phragmites From New Jersey (2016) Thermal constraints on stream consumer responses to a marine resource subsidy Final Report Water Temperature Regimes in the Togiak NWR and Wood-Tikchik State Park Compilation of Data for Parameterization of an Ecopath Model of Lake Superior at the Beginning of the 21st Century (2001-2016) Lake Ice Regime Classification