Filters: Tags: Fragmentation (X)
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Synopsis: This study attempts to build a forest fragmentation database for the conterminous United States by utilizing high-resolution NLCD data, roads, and a series of fragmentation indices that quantify forest landscape patterns. The paper outlines a methodology for assessing forest fragmentation and provides a comprehensive data set to be used as a base for further investigation at smaller scales. Conclusions: A forest fragmentation database for the conterminous United States was built to quantify forest landscape patterns nationwide. The paper outlines a methodology for assessing forest fragmentation and provides a comprehensive data set to be used as a base for further investigation at smaller scales. Thresholds/Learnings:...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Conterminous United States,
Land use configuration,
Landscape fragmentation,
Natural cover amount,
configuration,
Conclusions:Influx of woody vegetation associated with fragmentation correlates with decline in grassland bird speciesThresholds/Learnings:When native grassland cover dropped below 60% at one site, and 30-40% at another site, the arrangement or habitat patches became more important to the survival of populations than habitat amount alone
Categories: Publication;
Types: Citation;
Tags: Land use configuration,
Landscape fragmentation,
Natural cover heterogeneity,
Oklahoma,
biodiversity,
Conclusions: Marten capture rates were negatively correlated with increasing proximity of open areas and increasing extent of high-contrast edges. Forested landscapes were unsuitable for martens when the average nearest-neighbor distance between open, non-forested patches was <100m. Thresholds/Learnings: Synopsis: This study aimed to determine whether American marten abundance changed with incremental increases in habitat fragmentation caused by the combined effects of natural openings and timber clearcuts. Researchers evaluated differences in marten capture rates in 18 study sites with different levels of fragmentation. Martens appeared to respond negatively to low levels of habitat fragmentation, even with remaining...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: American martens,
Land use configuration,
Landscape fragmentation,
Natural cover amount,
Utah,
Synopsis: This study examined the reluctance of different birds species to cross habitat gaps in a fragmented forest landscape. Researchers induced birds in the post-fledging period to cross gaps of varying widths and to choose between routes through woodland or across open areas by attracting them with recorded chickadee mobbing calls. Overall, birds were twice as likely to travel through 50 m of woodland than they were to travel through 50 m of open gap areas to reach the recording. When given a choice of traveling through woodland or across a gap, the majority of birds preferred woodland routes, even when they were three times longer than shortcuts in the open. Birds did not just use movement corridors, but strongly...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Landscape fragmentation,
Quebec,
connectivity,
forest,
forest songbirds,
Control of invasive sea lamprey recruitment from tributary streams is a major management objective in the Great Lakes, and benefits from barriers that prevent access to spawning habitat. As society moves toward removal of more tributary barriers due to concerns about native migratory fishes, aging infrastructure, and vulnerability to climate-driven flooding, it is important to assess the costs of alternative options for sea lamprey control. This project is integrating cost estimates for application of a lamprey-specific pesticide into cost-benefit optimization models used to support decisions about barrier removals that maximize restoration of habitat for native species. By integrating lamprey control options...
Categories: Data,
Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2015,
Applications and Tools,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Federal resource managers,
Great Lakes,
Loss and fragmentation of grassland habitat can influence populations of the animal communities dependent upon this ecosystem. Grassland birds have faced notable declines in some areas of their range, potentially a result of changes to suitable habitat. Managing populations of grassland birds requires an understanding of the effects of habitat loss and fragmentation at a local and regional scale. We studied two grassland-dependent bird species, Eastern Meadowlarks (Sturnella magna) and Northern Bobwhites (Colinus virginianus), in an area of recent explosive growth in oil and gas related development. First, we quantified habitat lossand fragmentation of grassland habitat using remotely sensed datasets at multiple...
Fragmentation extent of six ecosystem types after European Settlement was analyzed using LANDFIRE data. The ecosystem types includes: Grassland, Shrubland, Conifer, Riparian, Hardwood and Sparse ecosystems. The land use change and fragmentation extents have been analyzed by delineating nine Greater Wildland Ecosystems (GWEs) across NCCSC.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Fragmentation,
Grasslands and Plains,
Greater Wildland Ecosystem,
LANDFIRE,
Land Use Land Cover,
Identified baseline sage grouse habitat using the greater sage grouse general habitat use model developed by Hanser and others (2011) based on sage grouse pellet surveys. Predictor variables in the model included percent cover of sagebrush shrublands (sagebrush steppe and mountain big sagebrush, which is part of the foothill shrublands and woodlands community) and riparian vegetation, annual minimum temperature, topographic roughness, and elevation. Data sources for vegetation include LANDFIRE v1.10 and PRISM. We masked out forest, open water, and elevations greater than 2,900 m. The map of potential habitat under baseline conditions was based on a probability of occurrence greater than 0.25; this probability threshold...
Why Rangelands: The Central Valley of California, the surrounding foothills and the interior Coast Range include over 18 million acres of grassland. Most of this land is privately owned and managed for livestock production. Because grasslands are found in some of California’s fastest-growing counties, they are severely threatened by land conversion and development. In addition climate change stresses grasslands by potentially changing water availability and species distributions.Maintaining a ranching landscape can greatly support biodiversity conservation in the California Landscape Conservation Cooperative (LCC) region. In addition ranches generate multiple ecosystem services—defined as human benefits provided...
Synopsis: Because recent bark beetle population eruptions have exceeded the frequencies, impacts, and ranges documented during the previous 125 years, researchers have been prompted to determine what factors trigger broad scale outbreaks, and how do these factors interact? How do human activities, such as forest management, alter these interactions, and thus the frequency, extent, severity, and synchrony of outbreaks? Extensive host tree abundance and susceptibility, concentrated beetle density, favorable weather, optimal symbiotic associations, and escape from natural enemies must occur jointly for beetles to surpass a series of thresholds and exert widespread disturbance. Eruptions occur when key thresholds are...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Alaska,
Alberta,
Arizona,
British Columbia,
California,
Synopsis: This study tested the null hypothesis that densities of mammalian populations are constant over patches of varied size. In other words, performance as estimated by density does not covary with patch area. Researchers used a composite database from published studies and found that densities of 20 out of 32 species did not vary with patch area. Five species showed increasing density-area relationships and seven species showed decreasing density-area relationships. Landscapes comprised of smaller, less isolated patched tended to have negative density-area relationships and landscapes with large, more isolated patched tended to have positive density-area relationships. These results indicate that there are...
Categories: Publication;
Types: Citation;
Tags: Density-area relationships,
Landscape fragmentation,
Natural cover amount,
configuration,
fragmentation,
Wind energy generation causes transformation of landscapes as new roads, pads, and transmission lines are constructed. We mapped, quantified, and analyzed the effects of facilities' geographic context on road networks and changes in landscape patterns by digitizing the footprints of 39 wind facilities and the surrounding land cover using high-resolution imagery of before and after construction. These data were used in understanding how new facilities change the amount of undeveloped land and changes in metrics of landscape patterns.
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Connectivity,
Core Area,
Development,
Energy,
Fragmentation,
Fragmentation extent of six ecosystem types after European Settlement was analyzed using LANDFIRE data. The ecosystem types includes: Grassland, Shrubland, Conifer, Riparian, Hardwood and Sparse ecosystems. The land use change and fragmentation extents have been analyzed by delineating nine Greater Wildland Ecosystems (GWEs) across NCCSC.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Fragmentation,
Grasslands and Plains,
Greater Wildland Ecosystem,
Housing Density,
LANDFIRE,
Land use change and fragmentation of Fort Peck Greater Wildland Ecosystems (GWE) using LANDFIRE data
Fragmentation extent of six ecosystem types after European Settlement was analyzed using LANDFIRE data. The ecosystem types includes: Grassland, Shrubland, Conifer, Riparian, Hardwood and Sparse ecosystems. The land use change and fragmentation extents have been analyzed by delineating nine Greater Wildland Ecosystems (GWEs) across NCCSC.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Fragmentation,
Grasslands and Plains,
Greater Wildland Ecosystem,
Housing Density,
Land Use Land Cover,
This map shows natural landscape fragmentation results from FRAGSTATS with 4KM and HUC5 reporting units. Fragmentation factors include impervious surfaces, developed areas, oil/gas wells, roads, utility lines, and pipelines. These data are provided by Bureau of Land Management (BLM) "as is" and may contain errors or omissions. The User assumes the entire risk associated with its use of these data and bears all responsibility in determining whether these data are fit for the User's intended use. These data may not have the accuracy, resolution, completeness, timeliness, or other characteristics appropriate for applications that potential users of the data may contemplate. The User is encouraged to carefully consider...
Synopsis: This foundational text focuses on the distribution patterns of landscape elements that affect flows of animals, plants, energy, mineral nutrients and water in an ecosystem. The book also discusses the ecological implications of landscape change over time. The book introduces the important and well documented concepts of patches, corridors, and a background matrix and the building blocks of landscape (figure 4). The patch-corridor-matrix model is thus comprised of these three principle components which, together, constitute a landscape mosaic: Patches are “relatively homogenous non-linear areas that differ from their surroundings”. Corridors are “strips of a particular patch type that differ from the adjacent...
Categories: Publication;
Types: Citation;
Tags: Global,
Land use configuration,
Landscape fragmentation,
Natural cover amount,
Natural cover heterogeneity,
Conclusions: Seismic cutline proportion did not explain landscape use by grizzly bears, but secondary effects of cutlines on landscape structure did. Declining use was mainly associated with increasing proportions of closed forest, and increasing variation of inter-patch distances, while use was mainly increasing with increasing mean patch size. Thresholds/Learnings: Bears appear to use areas more when landscape patches tend to be larger, and mean patch size is generally reduced with additional seismic cutlines. Also, bears appear to use areas more when landscape patches are consistently spaced, and the spacing between landscape patches becomes more variable with additional seismic cutlines. Synopsis: This study...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Binning,
GPS locations,
Generalized linear models (GLM),
Land use configuration,
Landscape configuration,
Synopsis: Large-scale patterns of land use and fragmentation have been associated with the decline of many imperiled wildlife populations. Lesser prairie-chickens (Tympanuchus pallidicinctus) are restricted to the southern Great Plains of North America, and their population and range have declined by > 90% over the past 100 years. Our objective was to examine scale-dependent relationships between landscape structure and change and long-term population trends for lesser prairie-chicken populations in the southern Great Plains. We used a geographic information system (GIS) to quantify landscape composition, pattern and change at multiple scales (extents) for fragmented agricultural landscapes surrounding 10 lesser...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Grasslands,
Land use configuration,
Landscape fragmentation,
Oklahoma/ Texas,
agriculture,
Mapping of barriers and statistical prediction of their passability is now fairly complete in the Great Lakes basin, yet field assessments of barrier characteristics and passability to migratory fishes are spotty. We will use the Lake Michigan basin as a pilot area for comprehensive field assessment of dam condition, dimensions, and passage technologies. These characteristics will be incorporated into our barrier database, enabling improved estimates of removal costs, watershed cumulative passability, and infrastructure maintenance challenges. In parallel, we will conduct field assessments of passability to spring migrations of Great Lakes fishes in 15 Wisconsin watersheds. Recording the upstream limits of migrations...
Categories: Data;
Tags: 2015,
Decision Support,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Federal resource managers,
Great Lakes,
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