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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...
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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.
This dataset is the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3800 observations representing 27 temperature manipulation studies, spanning nine biomes and nearly two decades of warming experiments. Data for this study were obtained from a combination of unpublished data and published literature values. We find that although warming increases soil respiration rates, there is limited evidence for a shifting respiration response with experimental warming. We also note a universal decline in the temperature sensitivity of respiration at soil temperatures >25°C. This dataset includes 3817 observations, from control (n=1812), first (i.e., lowest or sole) level...
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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.
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...
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NOTE: Two data download links are provided. The first includes the data described below as a geographic point layer and as a .csv file. The second link is a data package containing: the annual probability of observing one individual, the annual probability of encountering a large flock, and the monthly probability of observing one individual, for the full set of 24 species (in .csv format), and the associated report “Mapping the distribution, abundance and risk assessment of marine birds in the Northwest Atlantic.” To improve display of this data on Data Basin the point data was converted to a raster grid. This map depicts the mean predicted probability of observing at least one individual Black Scoter (Melanitta...
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NOTE: Two data download links are provided. The first includes the data described below as a geographic point layer and as a .csv file. The second link is a data package containing: the annual probability of observing one individual, the annual probability of encountering a large flock, and the monthly probability of observing one individual, for the full set of 24 species (in .csv format), and the associated report “Mapping the distribution, abundance and risk assessment of marine birds in the Northwest Atlantic.” To improve display of this data on Data Basin the point data was converted to a raster grid. This map depicts the mean predicted probability of observing at least one individual Common Eider (Somateria...
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NOTE: Two data download links are provided. The first includes the data described below as a geographic point layer and as a .csv file. The second link is a data package containing: the annual probability of observing one individual, the annual probability of encountering a large flock, and the monthly probability of observing one individual, for the full set of 24 species (in .csv format), and the associated report “Mapping the distribution, abundance and risk assessment of marine birds in the Northwest Atlantic.” To improve display of this data on Data Basin the point data was converted to a raster grid. This map depicts the mean predicted probability of observing at least one individual Wilson's Storm-petrel...
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...
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...
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This part of DS 781 presents data for the faults for the geologic and geomorphic map of the Offshore of Scott Creek map area, California. The vector data file is included in "Faults_OffshoreScottCreek.zip," which is accessible from http://dx.doi.org/10.5066/F7CJ8BJW.The offshore of Scott Creek map area straddles the right-lateral San Gregorio Fault Zone, an important structure in the distributed transform boundary between the North American and Pacific plates (see, for example, Dickinson and others, 2005). Regionally, this fault is part of a system that occurs predominantly in the offshore for about 400 km from Point Conception in the south (where it is known as the Hosgri fault; Johnson and Watt, 2012) to Bolinas...
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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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This part of DS 781 presents data for the sediment-thickness map of the Pigeon Point to Monterey, California, region. The raster data file is included in "SedimentThickness_PigeonPointToSouthMontereyBay.zip," which is accessible from http://dx.doi.org/10.5066/F7F47M6T 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 Pigeon Point and Monterey was generated from seismic-reflection data collected in 2009 and 2012 (USGS activities S-15-10-NC, S-06-11-MB and S-N1-09-MB) supplemented with outcrop and geologic structure from DS 781. The resulting grid covers an area of approximately 860 sq km. The volume of sediment...
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...
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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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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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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...


map background search result map search result map Faults--Offshore Scott Creek, California Predicted Annual Probability of Observing at least One Black Scoter Predicted Annual Probability of Observing at least One Common Eider Predicted Annual Probability of Observing at least One Wilson's Storm-petrel 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 Sediment Thickness--Pigeon Point to Monterey, California RWB 2004 Wetland Vegetation Faults--Offshore Scott Creek, California Fish Population and Hemlock data in Delware Water Gap 2012 Air and Temperature Data from Shenandoah National Park Sediment Thickness--Pigeon Point to Monterey, California RWB 2004 Wetland Vegetation LTRM Water Quality Sampling Strata Spring Season Habitat Suitability Index raster dataset Predicted Annual Probability of Observing at least One Common Eider Predicted Annual Probability of Observing at least One Wilson's Storm-petrel Predicted Annual Probability of Observing at least One Black Scoter UMRGLR JV - Wetland Breeding Bird Habitat Priorities Freshwater Ecoregions, Northeast