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From 2013 to 2015, bathymetric surveys of New York City’s six West of Hudson reservoirs (Ashokan, Cannonsville, Neversink, Pepacton, Rondout, and Schoharie) were performed to provide updated capacity tables and bathymetric maps. Depths were surveyed with a single-beam echo sounder and real-time kinematic global positioning system (RTK-GPS) along planned transects at predetermined intervals for each reservoir. A separate set of echo sounder data was collected along transects at oblique angles to the main transects for accuracy assessment. Field survey data was combined with water-surface elevations in a geographic information system to create three-dimensional surfaces representing reservoir-bed elevations in the...
In this paper, we provide an assessment of plantation forests and private land resources potentially available for pine plantation development in 11 southern states of the United States. After a sustained growth for 50 years, plantation forests (softwood and hardwood on both private and public lands) amounted to 18 million ha or 24 percent of all timberlands in these states in 2007. The vast majority of the plantation forests were established on private lands with fast-growing loblolly pines and slash pines. While purposeful hardwood plantations were rare, there were hardwood stands growing on failed pine plantation sites. Using a two-stage Markov land use transition model, we forecast that private forest land in...
In this paper, we provide an assessment of plantation forests and private land resources potentially available for pine plantation development in 11 southern states of the United States. After a sustained growth for 50 years, plantation forests (softwood and hardwood on both private and public lands) amounted to 18 million ha or 24 percent of all timberlands in these states in 2007. The vast majority of the plantation forests were established on private lands with fast-growing loblolly pines and slash pines. While purposeful hardwood plantations were rare, there were hardwood stands growing on failed pine plantation sites. Using a two-stage Markov land use transition model, we forecast that private forest land in...
If conservation of biodiversity is the goal, then the protected areas network of the continental US may be one of our best conservation tools for safeguarding ecological systems (i.e., vegetation communities). We evaluated representation of ecological systems in the current protected areas network and found insufficient representation at three vegetation community levels within lower elevations and moderate to high productivity soils. We used national-level data for ecological systems and a protected areas database to explore alternative ways we might be able to increase representation of ecological systems within the continental US. By following one or more of these alternatives it may be possible to increase the...
Categories: Publication;
Types: Citation;
Tags: Biodiversity,
Conservation of Natural Resources,
Ecosystem,
Environment,
Geography,
Well-established conservation planning principles and techniques framed by geodesign were used to assess the restorability of areas that historically supported coastal wetlands along the U.S. shore of Saginaw Bay. The resulting analysis supported planning efforts to identify, prioritize, and track wetland restoration opportunity and investment in the region. To accomplish this, publicly available data, criteria derived from the regional managers and local stakeholders, and geospatial analysis were used to form an ecological model for spatial prioritization.
Stable isotopes of delta(18)O, delta(2)H, and (13)C, radiogenic isotopes of (14)C and (3)H, and ground water chemical compositions were used to distinguish ground water, recharge areas, and possible recharge processes in an arid zone, fault-bounded alluvial aquifer. Recharge mainly occurs through exposed stream channel beds as opposed to subsurface inflow along mountain fronts. This recharge distribution pattern may also occur in other fault-bounded aquifers, with important implications for conceptualization of ground water flow systems, development of ground water models, and ground water resource management. Ground water along the mountain front near the basin margins contains low delta(18)O, (14)C (percent modern...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Ground Water,
Isotopes: analysis,
altitude,
environmental monitoring,
environmental monitoring: methods,
In this paper, we provide an assessment of plantation forests and private land resources potentially available for pine plantation development in 11 southern states of the United States. After a sustained growth for 50 years, plantation forests (softwood and hardwood on both private and public lands) amounted to 18 million ha or 24 percent of all timberlands in these states in 2007. The vast majority of the plantation forests were established on private lands with fast-growing loblolly pines and slash pines. While purposeful hardwood plantations were rare, there were hardwood stands growing on failed pine plantation sites. Using a two-stage Markov land use transition model, we forecast that private forest land in...
This dataset documents results from 1,041 groundwater samples collected during 1986‒2015 from 16 geologic units in Pennsylvania associated with 25 or more groundwater samples with activities or concentrations of radon-222. Radon-222 is hereafter referred to as “radon.” These 16 geologic units were evaluated in an effort to identify variations in radon concentrations and to classify potential radon exposure from groundwater and indoor air. This dataset was developed for the Pennsylvania Environmental Public Health Tracking (PAEPHT) Program to describe the spatial distribution of radon concentrations in groundwater in Pennsylvania and to illustrate data gaps that exist throughout the State. The PAEPHT Program is part...
Categories: Data;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Environmental Health,
Geography,
Hydrogeology,
Pennsylvania,
USGS Science Data Catalog (SDC),
We estimated global cyanobacterial biomass in the main reservoirs of cyanobacteria on Earth: marine and freshwater plankton, arid land soil crusts, and endoliths. Estimates were based on typical population density values as measured during our research, or as obtained from literature surveys, which were then coupled with data on global geographical area coverage. Among the marine plankton, the global biomass of Prochlorococcus reaches 120 × 10^12 grams of carbon (g C), and that of Synechoccus some 43 × 10^12 g C. This makes Prochlorococcus and Synechococcus, in that order, the most abundant cyanobacteria on Earth. Tropical marine blooms of Trichodesmium account for an additional 10 × 10^12 g C worldwide. In terrestrial...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Algological Studies,
Cyanobacteria,
abundance,
arid land soils,
benthos,
Anthropogenic impervious surfaces affect hydrology, water quality, and ecological health and are widely studied. Previous studies have been limited, however, by a lack of consistent representation of imperviousness nationally as a time series prior to 2001. This product presents estimated imperviousness at 60-meter spatial resolution, for the time periods 1974, 1982, 1992, 2002, and 2012. The mapping was derived by comparing imperviousness from the National Land Cover Database (NLCD) 2011 to national land use from the 2012 U.S. Geological Survey NAWQA Wall-to-wall Anthropogenic Land Use Trends (NWALT) product. The NWALT land use product includes a series of 60-m national rasters, containing 18 land use classes,...
Types: Citation;
Tags: Coefficients of imperviousness,
Geography,
Imperviousness,
Land Use Change,
Land use,
This dataset is the output of a python script/ArcGIS model that identifes dikes as having a difference in elevation above a certain threshold. If the elevation difference was below a certain threshold the area was not considered a dike; however, if the difference in elevation between two points was significantly high then the area was marked as a dike. Areas continuous with eachother were considered part of the same dike. Post processing occured. Users examined the data output, comparing the proposed dike locations to aerial imagery, flowline data, and the DEM. Dikes that appeared to be false positives were deleted from the data set.
Categories: Data;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Great Lakes,
LIDAR,
Lake Erie,
biogeography,
coastal ecosystems,
Sediment erosion and deposition in two sets of paired (treated and untreated) upland drainages in the Torreon Wash watershed, upper Rio Puerco Basin, New Mexico, were examined over a 3 1/2-year period from spring 2009 through fall 2012. The objective was to evaluate the effectiveness of shallow, loose-stone check dams, or “one-rock dams,” as a hillslope gully erosion stabilization and mitigation method, and its potential for retaining upland eroded soils and decreasing delivery of sediment to lower ephemeral stream channels. Two high-resolution topographic surveys, completed at the beginning and end of the study period, were used to assess the impact of the mitigation measures in both Penistaja Tributary Arroyo...
Categories: Data;
Types: Citation;
Tags: Environmental Health,
Geography,
Geomorphology,
NM,
North America,
This dataset is the output of a python script/ArcGIS model that identifes dikes as having a difference in elevation above a certain threshold. If the elevation difference was below a certain threshold the area was not considered a dike; however, if the difference in elevation between two points was significantly high then the area was marked as a dike. Areas continuous with eachother were considered part of the same dike. Post processing occured. Users examined the data output, comparing the proposed dike locations to aerial imagery, flowline data, and the DEM. Dikes that appeared to be false positives were deleted from the data set.
Categories: Data;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Detroit River,
Great Lakes,
LIDAR,
Lake St. Clair,
St. Clair River,
From 2013 to 2015, bathymetric surveys of New York City’s six West of Hudson reservoirs (Ashokan, Cannonsville, Neversink, Pepacton, Rondout, and Schoharie) were performed to provide updated capacity tables and bathymetric maps. Depths were surveyed with a single-beam echo sounder and real-time kinematic global positioning system (RTK-GPS) along planned transects at predetermined intervals for each reservoir. A separate set of echo sounder data was collected along transects at oblique angles to the main transects for accuracy assessment. Field survey data was combined with water-surface elevations in a geographic information system to create three-dimensional surfaces representing reservoir-bed elevations in the...
From 2013 to 2015, bathymetric surveys of New York City’s six West of Hudson reservoirs (Ashokan, Cannonsville, Neversink, Pepacton, Rondout, and Schoharie) were performed to provide updated capacity tables and bathymetric maps. Depths were surveyed with a single-beam echo sounder and real-time kinematic global positioning system (RTK-GPS) along planned transects at predetermined intervals for each reservoir. A separate set of echo sounder data was collected along transects at oblique angles to the main transects for accuracy assessment. Field survey data was combined with water-surface elevations in a geographic information system to create three-dimensional surfaces representing reservoir-bed elevations in the...
Many ecosystems exist primarily, or solely, on privately owned (freehold) or managed (leasehold) land. In rural and semirural areas, local and regional government agencies are commonly responsible for encouraging landholders to conserve native vegetation and species on these private properties. Yet these agencies often lack the capacity to design and implement conservation programs tailored to rural and semirural landholdings and instead offer one program to all landholders. Landholders may elect not to participate because the program is irrelevant to their property or personal needs; consequently, vegetation-retention objectives may not be achieved. We differentiated landholders in Queensland, Australia, according...
Categories: Publication;
Types: Citation;
Tags: *Ecosystem,
Conservation of Natural Resources/*methods,
Geography,
Motivation,
Queensland,
The main concept currently in use in wind energy involves horizontal-axis wind turbines with blades of fiber composite materials. This turbine concept is expected to remain as the major provider of wind power in the foreseeable future. However, turbine sizes are increasing, and installation offshore means that wind turbines will be exposed to more demanding environmental conditions. Many challenges are posed by the use of fiber composites in increasingly large blades and increasingly hostile environments. Among these are achieving adequate stiffness to prevent excessive blade deflection, preventing buckling failure, ensuring adequate fatigue life under variable wind loading combined with gravitational loading, and...
This polygon shapefile provides county or county-equivalent boundaries for the conterminous United States and was created specifically for use with the data tables published as Selected Items from the Census of Agriculture for the Conterminous United States, 1950-2012 (LaMotte, 2015). This data layer is a modified version of Historic Counties for the 2000 Census of Population and Housing produced by the National Historical Geographic Information System (NHGIS) project, which is identical to the U.S. Census Bureau TIGER/Line Census 2000 file, with the exception of added shorelines. Excluded from the CAO_STCOFIPS boundary layer are Broomfield County, Colorado, Menominee County, Wisconsin, and the independent cities...
Well-established conservation planning principles and techniques framed by geodesign were used to assess the restorability of areas that historically supported coastal wetlands along the U.S. shore of the connecting rivers (Detroit River and St. Clair River). The resulting analysis supported planning efforts to identify, prioritize, and track wetland restoration opportunity and investment in the region. To accomplish this, publicly available data, criteria derived from the regional managers and local stakeholders, and geospatial analysis were used to form an ecological model for spatial prioritization.
This represents the flowline network in Western Lale Erie Restoration Assessment (WLERA). It is attributed with the number of disconnections between the reach and the connecting river system. These data will help identify the condition of hydrologic separation between potential restoration areas and the connecting river system. Low numbers represent fewer disconnections such as culverts between the reach and the rivers requiring no flow network modification to restore the area.
Categories: Data;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Artificial Path,
Canal / Ditch,
FWHydrography,
Great Lakes,
Hydrography,
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