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Synopsis: This report evaluates habitat requirements of the American badger according to parameters of soil texture, graminoid cover, slope, and proximity to roads. Badgers tend to prefer sandy loam and silty loam, medium and moderately coarse textured soils. In terms of graminoid coverage, badgers generally prefer open grassland habitat, but can also be found in agriculturally dominated landscapes containing isolated pockets of Richardson 's ground squirrel colonies. Graminoid coverage of 23% was chosen as the minimum requirement for suitable badger habitat. As slope increases, habitat suitability decreases to a point at which the likelihood of badgers existing there (i.e. cliffs and badlands) is extremely low...
Synopsis: This study aimed to independently examine the effects of varying amounts and configurations of habitat at a landscape scale, with particular attention to critical persistence thresholds. A discrete reaction-diffusion model was used to estimate long-term equilibrium population persistence of a hypothetical species in a patchy landscape. When examined over a broad range of habitat amount and arrangements, population size was largely determined by the proportion of habitat (amount) in a landscape. However, when habitat coverage dropped below 30-50%, population response deviated, coinciding with a persistence threshold. Species persistence declined rapidly at this threshold range (50% for low degrees of aggregation,...
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Synopsis: This study summarized results of a comparative 15N-tracer study from a wide variety of sites throughout the United States, to derive general principles related to headwater streams and nitrogen dynamics. Standardized protocols were applied in 12 headwater streams representing a wide diversity of biomes throughout the United States. These sites were part of the Lotic Intersite Nitrogen eXperiment (LINX). The most rapid uptake and transformation of inorganic nitrogen occurred in the smallest streams. Ammonium entering these streams was removed within a few tens to hundreds of meters, primarily through assimilation by microorganisms, sorption to sediments, and nitrification. Nitrate was also removed from...
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Synopsis: This model is based around Native Prairie Cover types, and Soil Texture. Native Prairie Class (NPC) is derived from the Native Prairie Vegetation Baseline Inventory developed by AlbertaEnvironment. Class I is comprised of greater than 75% native prairie components (i.e. shrubs, graminoids, riparian areas, lakes, wetlands, and trees), Class 2 is 50 - 75%, Class 3 is 25 - 50%, Class 4 is 1 - 25%, and Class 5 is no native prairie components. Native prairie is probably the most important and limiting factor for ferruginous hawks. Although hawks have been found in areas that were primarily under cultivation), they were in close proximity to prairie in good condition. Overall NPC was selected over its individual...
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Synopsis: This document details the Milk River Basin project, designed to produce innovative approaches to multi-species management in Southern Alberta. The Milk River basin contains a variety of ‘sensitive’, ‘at risk’, and ‘may be at risk’ species. The process of prioritizing the landscape for conservation and stewardship was driven by species inventories to identify known locations, and Habitat Suitability Index (HSI) models to delimit suitable key habitat for the 17 selected species. The construction of the models was limited to the available variables and resolution of the databases. For MULTISAR: the Milk River Basin Project area this was the quarter section, the resolution of the Native Prairie Vegetation...
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Synopsis: This paper describes the spatial distribution of pH measurements from 60 sites distributed throughout the Kychlan River catchment, a 67km⊃2; boreal watershed in northern Sweden. Water samples were collected during a period of winter baseflow and during a spring flood episode. Chemical analyses included pH, Dissolved Organic Carbon (DOC), major cations (K, Mg, Na, Ca) and total filterable aluminum. Spring flood pH was shown to be highest in larger, lower altitude catchments underlain by fine sorted sediments, and lowest in small, higher altitude catchments underlain by a mixture of peat wetlands and forested till. There was also a trend with distance downstream of higher pH, acid neutralizing capacity and...


    map background search result map search result map Ferruginous Hawk. Control of Nitrogen Export from Watersheds by Headwater Streams The Milk River Basin Project; Habitat Suitability Models for Selected Wildlife Management Species No. 86. Alberta Species At Risk Report, Alberta Sustainable Resource Development, 2004 Spatial heterogeneity of the spring flood acid pulse in a boreal stream network. American Badger. Spatial heterogeneity of the spring flood acid pulse in a boreal stream network. Control of Nitrogen Export from Watersheds by Headwater Streams