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Information on future land-use and land-cover (LULC) change is needed to analyze the impact of LULC change on ecological processes. The U.S. Geological Survey has produced spatially explicit, thematically detailed LULC projections for the conterminous United States. Four qualitative and quantitative scenarios of LULC change were developed, with characteristics consistent with the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emission Scenarios (SRES). The four quantified scenarios (A1B, A2, B1, and B2) served as input to the forecasting scenarios of land-use change (FORE-SCE) model. Four spatially explicit data sets consistent with scenario storylines were produced for the conterminous United...
Riverine exports of organic and inorganic carbon (OC, IC) to oceans are intricately linked to processes occurring on land. Across high latitudes, thawing permafrost, alteration of hydrologic flow paths, and changes in vegetation may all affect this flux, with subsequent implications for regional and global carbon (C) budgets. Using a unique, multi-decadal dataset of continuous discharge coupled with water chemistry measurements for the Mackenzie River, we show major increases in dissolved OC (DOC) and IC (as alkalinity) fluxes since the early 1970s, for a watershed that covers 1.8 M km2 of northwestern Canada, and provides substantial inputs of freshwater and biogeochemical constituents to the Arctic Ocean. Over...
Soil organic carbon (SOC) storage plays a major role in the global carbon cycle and is affected by many factors including land use/management changes (e.g., biofuel production-oriented changes). However, the contributions of various factors to SOC changes are not well understood and quantified. This study was designed to investigate the impacts of changing farming practices, initial SOC levels, and biological enhancement of grain production on SOC dynamics and to attribute the relative contributions of major driving forces (CO2 enrichment and farming practices) using a fractional factorial modeling design. The case study at a crop site in Iowa in the United States demonstrated that the traditional corn-soybean (CS)...
Spatially-explicit state-and-transition simulation models of land use and land cover (LULC) increase our ability to assess regional landscape characteristics and associated carbon dynamics across multiple scenarios. By characterizing appropriate spatial attributes such as forest age and land-use distribution, a state-and-transition model can more effectively simulate the pattern and spread of LULC changes. This manuscript describes the methods and input parameters of the Land Use and Carbon Scenario Simulator (LUCAS), a customized state-and-transition simulation model utilized to assess the relative impacts of LULC on carbon stocks for the conterminous U.S. The methods and input parameters are spatially explicit...
Terrestrial carbon sequestration potential is widely considered as a realistic option for mitigating greenhouse gas emissions. However, this potential may be threatened by global changes including climate, land use, and management changes such as increased corn stover harvesting for rising production of cellulosic biofuel. Therefore, it is critical to investigate the dynamics of soil organic carbon (SOC) at regional or global scale. This study simulated the corn production and spatiotemporal changes of SOC in the U.S. Temperate Prairies, which covers over one-third of the U.S. corn acreage, using a biogeochemical model with multiple climate and land-use change projections. The corn production (either grain yield...
Cultivated lands in the U.S. Midwest have been affected by soil erosion, causing soil organic carbon (SOC) redistribution in the landscape and other environmental and agricultural problems. The importance of SOC redistribution on soil productivity and crop yield, however, is still uncertain. In this study, we used a model framework, which includes the Unit Stream Power-based Erosion Deposition (USPED) and the Tillage Erosion Prediction (TEP) models, to understand the soil and SOC redistribution caused by water and tillage erosion in two agricultural fields in the U.S. Midwest. This model framework was evaluated for different digital elevation model (DEM) spatial resolutions (10-m, 24-m, 30-m, and 56-m) and topographic...
A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Wildlife Biology Utah State University, Logan, Utah Abstract: "Declines in the distribution and abundance of greater sage-grouse ( Centrocercus urophasianus ; hereafter “sage - grouse” ) in western North America over the past century have been severe. The goal of my research was to increase the understanding of factors influencing where sage-grouse hens placed their nests, how common ravens ( Corvus corax : hereafter “raven” ) impacted sage-grouse nest success, and whether high raptor densities negatively impacted hen survival of sage-grouse. I compared raven and raptor densities at sage-grouse nest...
Whooping cranes (Grus americana) of the Aransas-Wood Buffalo population migrate twice each year through the Great Plains in North America. Recovery activities for this endangered species include providing adequate places to stop and rest during migration, which are generally referred to as stopover sites. To assist in recovery efforts, initial estimates of stopover site use intensity are presented, which provide opportunity to identify areas across the migration range used more intensively by whooping cranes. We used location data acquired from 58 unique individuals fitted with platform transmitting terminals that collected global position system locations. Radio-tagged birds provided 2,158 stopover sites over 10...
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Forest- Data collected once using GIS prior to fish sampling. Our approach was to focus the study on smaller, headwater catchments because larger streams drained areas containing both hemlock and mixed hardwood forest, making forest-specific comparison intractable. In addition, most of these larger watersheds were impacted by humans (e.g., impoundments, agriculture, quarries) that could confound our assessment of the influence of hemlock. Even after limiting the study to headwater catchments, other possible confounding factors remained; we controlled for landscape variability (i.e., terrain and stream size) through the sampling design and we excluded others (i.e., minimum catchment area,beaver activity) through...
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Raw data were collected in Shenandoah National Park during summer 2012. Air and temperature data were collected using temperature loggers at several stations throughout the park. These data were used in the publication of the manuscript "Accounting for groundwater influence on headwater stream thermal sensitivity to climate change" through the journal Ecological Applications. Water temperature data were collected at all 78 reach locations during the summer of 2012 (23 June–7 September). Temperature was measured every hour with a logger.
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Remote camera data on snow presence, snow depth, and wildlife detections on Moscow Mountain in Latah County, ID, USA. Reconyx Hyperfire I and Hyperfire II cameras were used and set to take hourly timelapse images and motion-triggered images. The cameras were deployed from October 2020 - May 2021. Snow presence was assessed up to 15 m from the camera. Snow depth was measured using virtual snow stakes created with the edger R package created by the author. Wildlife were marked as present in all photos in which they appear, and new individuals were counted. Snow density was collected using a federal or prairie snow sampler. Snow hardness was collected using a ram penetrometer. Solar radiation was calculated using hemispherical...
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We collected snow density measurements at camera sites from December 2020 - April 2021, at the same time as snow hardness measurements. We took measurements every few weeks as logistics allowed. We took samples near the camera site in snow visually similar to the snow in the camera viewshed (the geographical area that is visible from a location) to prevent snow conditions from being disturbed beyond normal camera deployment. We took snow density samples using a homemade prairie sampler in snow depths < 100 cm and using a federal snow sampler in snow depths > 100 cm. The sampler was inserted into the snow to remove a snow core. We retained the core if the depth of snow in the sampler was at least 90% of the actual...
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This raster represents a continuous surface of sage-grouse habitat suitability index (HSI,created using ArcGIS 10.2.2) values for Nevada during the breeding season.
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This layer depicts the status, or degree of disturbance, to plant communities on the main Hawaiian Islands. To more precisely identify areas where native species may presently be found, a map was generated that considers the following three categories of habitat quality: High, areas dominated by native vegetation; Medium, areas dominated by nonnative vegetation; and Low, highly modified landscapes. The primary source for mapping these three categories is the HIGAP land-cover classification (Gon, 2006). The High category includes all HIGAP land-cover classes that are considered to be either native dominated or mixed native and nonnative in order to represent those areas that have substantial native-species composition....
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NOTE: This download link includes Fish Regions, Freshwater Ecoregions, and Freshwater Resilience. Freshwater ecoregions provide a global biogeographic regionalization of the Earth's freshwater biodiversity. These units are distinguished by patterns of native fish distribution resulting from large-scale geoclimatic processes and evolutionary history. The freshwater ecoregion boundaries generally, though not always, correspond with those of watersheds. Within individual ecoregions there will be turnover of species, such as when moving up or down a river system, but taken as a whole an ecoregion will typically have a distinct evolutionary history and/or suite of ecological processes (Abell et al. 2008). The WWF defined...
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Resilient stream systems are those that will support a full spectrum of biodiversity and maintain their functional integrity even as species compositions and hydrologic properties change in response to shifts in ambient conditions due to climate change. We examined all connected stream networks in the Northeast and Mid-Atlantic for seven characteristics correlated with resilience. These included four physical properties (network length, number of size classes, number of gradients classes and number of temperature classes), and three condition characteristics (risk of hydrologic alterations, natural cover in the floodplain, and amount of impervious surface in the watershed). A network was defined as a continuous...
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The Rainwater Basin (RWB) wetland complex in south-central Nebraska provides crucial stopover habitat for over 7 million waterfowl and 500,000 shorebirds every spring. However, only 10% of the original RWB wetlands remain, resulting in less available habitat for wetland-dependent birds. Conservation efforts are being employed to alleviate the loss of RWB wetlands. To aid conservation efforts, we created a vegetation map of all historical RWB wetlands based on 2004 imagery. The shapefile maps the 2004 vegetation communities for all historic wetlands in the Rainwater Basin region of Nebraska, USA. Vegetation communities include cropped areas that rarely pond water, cropped areas that often pond water, bare soil...
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The data set includes delineation of sampling strata for the six study reaches of the UMRR Program’s LTRM element. Separate strata coverages exist for each of the three monitoring components (fish, vegetation, and water quality) to meet the differing sampling needs among components. Generally, the sampling strata consist of main channel, side channel, backwater, and impounded areas. The fish component further delineates a “shoreline” portion of the strata to be used for sampling gears deployed only along the shoreline. The data are raster in origin, with the center of each pixel representing the sampling location. Cell size is typically 50 meters, although several water quality strata are at 200 meter cell size.
map background search result map search result map Freshwater Resilience, All Streams, Stratified by Fish Region and Freshwater Ecoregion, Northeast U.S. Hawaii Habitat Quality (HI_HabQual) Freshwater Ecoregions, Northeast UMRGLR JV - Wetland Breeding Bird Habitat Priorities 2012 Air and Temperature Data from Shenandoah National Park Fish Population and Hemlock data in Delware Water Gap LTRM Water Quality Sampling Strata Spring Season Habitat Suitability Index raster dataset Rainwater Basin Wetland Complex Vegetation Map 2004 Snow Density Measurements at Remote Camera Stations on Moscow Mountain in Latah County, ID (12/1/20-4/30/21) Environmental Data at Remote Camera Stations on Moscow Mountain in Latah County, ID, USA (10/20/20-5/30/21) Snow Density Measurements at Remote Camera Stations on Moscow Mountain in Latah County, ID (12/1/20-4/30/21) Environmental Data at Remote Camera Stations on Moscow Mountain in Latah County, ID, USA (10/20/20-5/30/21) Fish Population and Hemlock data in Delware Water Gap 2012 Air and Temperature Data from Shenandoah National Park Rainwater Basin Wetland Complex Vegetation Map 2004 Hawaii Habitat Quality (HI_HabQual) LTRM Water Quality Sampling Strata Spring Season Habitat Suitability Index raster dataset UMRGLR JV - Wetland Breeding Bird Habitat Priorities Freshwater Resilience, All Streams, Stratified by Fish Region and Freshwater Ecoregion, Northeast U.S. Freshwater Ecoregions, Northeast