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Filters: partyWithName: U.S. Geological Survey (X) > Types: Downloadable (X) > partyWithName: Steven E. Hanser (X) > partyWithName: Matthias Leu (X)

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Development of oil and gas wells leads to the destruction and fragmentation of natural habitat. Oil and gas wells also increase noise levels which has been shown to be detrimental to some wildlife species. Therefore, the density of oil and gas wells in the western United States was modeled based on data obtained from the National Oil and Gas Assessment.
This model is based on how house cats utilize wildlands near human habituation. These predators can have detrimental effects on wildlife populations (Alterio et al. 1998). We based our model on the data collected by Odell and Knight (2001) that investigated habitat utilization of these predators with regard to distance from housing and on the probability for a homeowner to possess a house cat. We buffered the populated areas distance layer in ARC/INFO using a probability function [P = 0.216 - 0.96 * Distance (km)] where any cell with distance less than 0.18km received a probability between 0.216 to 0. All distances greater than or equal to 0.18km from populated areas were assigned a probability of 0. The resulting...
Density of linear features, such as roads, power lines, telephone lines, and railroad tracks have been shown to influence synanthropic predator abundance patterns (Knight et al. 1995). Following Knight et al. (1995), we used linear features such as roads, railroads, and power line spatial data sets, but also included irrigation canals, to build a linear features spatial data set. However, we lacked spatial data on telephone and feeder-power lines and therefore our linear feature spatial data set vastly underestimates the number of linear features in some areas.
Humans have dramatically altered wildlands in the western United States over the past 100 years by using these lands and the resources they provide. Anthropogenic changes to the landscape, such as urban expansion, construction of roads, power lines, and other networks and land uses necessary to maintain human populations influence the number and kinds of plants and wildlife that remain. We developed the map of the human footprint for the western United States from an analysis of 14 landscape structure and anthropogenic features: human habitation, interstate highways, federal and state highways, secondary roads, railroads, irrigation canals, power lines, linear feature densities, agricultural land, campgrounds, highway...
This model was constructed to model the risk of invasion by exotic plant species. Roads may directly influence exotic plant dispersal via disturbance during road construction or via alterations in soil regimes. For example, in Californian serpentine soil ecosystems, exotic plant species can be found up to 1km from the nearest road and Russian thistle (Salsola kali), an exotic forb growing along roads, is wind-dispersed over distances greater than 4km. Roads may also indirectly facilitate the dispersal of exotic grasses, such as crested wheatgrass (Agropyron cristatum), via human seeding along road verges or in burned areas near roads as a management strategy to curb the establishment of less desirable exotic grass...
This model is based on how dogs utilize wildlands near human habituation. These predators can have detrimental effects on wildlife populations (Alterio et al. 1998). We based our model on the data collected by Odell and Knight (2001) that investigated habitat utilization of these predators with regard to distance from housing and on the probability for a homeowner to possess a dog. We buffered both the populated areas and the campground distance layers in ARC/INFO using probability functions [P = 0.548 - 1.4589 * Distance (km)]. Any cell with distance less than 0.36km received a probability based on the function (0.556 to 0.001572) and all distances greater than or equal to 0.36km from populated areas or campgrounds...
    map background search result map search result map Probability of Synanthropic Feral House Cat Presence in the Western United States Probability of Synanthropic Feral Dog Presence in the Western United States Exotic Plant Invasion Risk in the Western United States The Human Footprint in the West Density of Line Features in the Western United States Oil and Gas Well Density in the Western United States The Human Footprint in the West Exotic Plant Invasion Risk in the Western United States Density of Line Features in the Western United States Probability of Synanthropic Feral House Cat Presence in the Western United States Probability of Synanthropic Feral Dog Presence in the Western United States Oil and Gas Well Density in the Western United States