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Synopsis: Prior to European settlement, the Northern Mixed-grass Prairie was a mosaic of wetland, grassland and grass-shrub habitats, with riparian and floodplain forests along major drainages. Even today, the physiographic area can be characterized as being one of the largest still relatively intact grassland landscapes that persist in North America. It is the continent’s most important production area for waterfowl and is the heart of the breeding range for some of North America’s rarest species of grassland birds. A comparison of relative abundance estimates among physiographic areas sampled by the North American Breeding Bird Survey indicates that more than 40% of the world’s population of Baird’s Sparrows,...
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Conclusions: In fragmented watersheds, macrohabitat attributes measured at the patch scale were far more effective in predicting trout translocation success than measurements taken at the landscape scale Thresholds/Learnings: As a course filter indicator of cutthroat trout translocation success, the study found that translocations have a greater than 50% chance of fruitful establishment in watersheds >14.7km2 in area. Synopsis: This study aimed to identify stream-scale and basin-scale macrohabitat attributes limiting successful translocation and persistence of native cutthroat trout populations in fragmented landscapes along the Rio Grande. The study developed models of habitat attributes measured at two scales...
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Synopsis: This study analyzed the effects of vegetation change on hydrological fluctuations in the Columbia River basin over the last century using two land cover scenarios. The first scenario was a reconstruction of historical land cover vegetation, c. 1900. The second scenario was more recent land cover as estimated from remote sensing data for 1990. The results show that, hydrologically, the most important vegetation-related change has been a general tendency towards decreased vegetation maturity in the forested areas of the basin. This general trend represents a balance between the effects of logging and fire suppression. In those areas where forest maturity has been reduced as a result of logging, wintertime...
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Synopsis: Using multi-scale seasonal models, this study explored how broad scale landscape context and local resource heterogeneity influenced local resource selection among threatened forest-dwelling woodland caribou in southern Quebec. Caribou consistently avoided roads, however researchers identified thresholds in road proximity effects. The threshold distance at which caribou avoid roads is 1.25 km for active roads and 0.75 km from derelict roads. Open lichen woodlands were an important cover type for caribou during winter and spring, whereas deciduous forests, wetlands, and even young disturbed stands became important during calving and summer. Landscape cover type and amount explained more variation in habitat...
Conclusions:The Sprague's pipit tends to occupy native grassland habitats containing very little or no woody vegetation, with non-native areas populated to a significantly lower extentThresholds/Learnings:
Conclusions:Owls avoided agricultural lands (due to prey availability), used grass-forb areas for foraging, and avoided croplands and grazed pasture. 95% of all movements occurred within 600 meters of the nest burrows.Thresholds/Learnings:At a minimum, a 600m radius should be maintained around burrowing owl nests in order to ensure the survival of burrowing owls
Conclusions:Wetland extent, proximity of wetlands to the sampling station, and the position of a wetland in a watershed (downstream wetlands have greater influence on water quality) influence water quality.Thresholds/Learnings:
Conclusions:Variability in buffer width across a landscape has important effects on landscape discharge. A variable- width buffer retains less material than a uniform-width buffer of equivalent average width.Thresholds/Learnings:
Conclusions:Study found statistically significant relationships among source water quality, percent land cover, and drinking water treatment cost. Increased percent agriculture and urban cover were significantly related to decreased water quality, while decreased forest land cover was significantly related to decreased water quality. High percent land cover by non-forest vegetation was significantly related to low treatment cost.Thresholds/Learnings:
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Synopsis: This article outlines how wetlands can significantly reduce flooding in the Upper Mississippi watershed. The authors first provide a historical context by estimating the original and lost wetland storage capacities of the Upper Mississippi and Missouri River Basins. Historically, about 10% of the basin would have been classified as wetland in 1780. By 1980, wetland acreage had been reduced to only 4% of the basin, representing about 26 million acres of wetlands eliminated since 1780. The area of wetland restoration required to reduce the risk of future flooding adequately was estimated based on the total amount of excess floodwater beyond bank-full discharge that passed through the City of St. Louis during...
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Synopsis: The purpose of this model is to indicate potential habitat for olive-backed pocket mice (Perohnathus fasciatus) within the Milk River Basin. As this is a landscape level model with course variaqbles, it may not be directly applicable to other areas for site-specific analysis. Conclusions: Olive-backed pocket mice require high proportions of grassland habitat and low proportions of shrub cover. Sites with low densities of shrubs are preferred because they provide cover from large and aerial predators, such as owls. A threshold of below 40% shrub coverage represents ideal shrub cover proportions.
Conclusions:Report synthesizes scientific, planning, and policy-related aspects on the importance of land conservation in areas producing water for potable uses, including watersheds and aquifers. One critical finding indicated that if there is more forest cover in a watershed, water treatment costs are lower.Thresholds/Learnings:For every 10% increase in forest cover in the source area, treatment and chemical costs decreased by about 20%, up to about 60% forest cover. Treatment costs level off when forest cover is between 70-100%.
Conclusions:This report sets out guidelines intended to provide BCEAG member jurisdictions with a coordinated approach to recommendations regarding the management of human use activities within wildlife corridors and habitat patches in the Bow Valley of Alberta. The guidelines provide an advisory framework for decision making related to wildlife management as well as recommendations for mitigating the negative effects of human activity on wildlife in the region.Thresholds/Learnings:Male and female cougars avoided areas of high human use and where human use levels exceeded 250-500 users per month.
Conclusions:Landscapes dominated by woody vegetation had significantly more patches, smaller patches and patch core areas, more total edge, and higher patch diversity than landscapes dominated by anthropogenic cover types. Results indicate that expanding juniper is exacerbating the fragmentation process initiated by previous human activityThresholds/Learnings:
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Conclusions: Report presents a framework for assessing the condition of Southern Alberta’s natural assets and their ability to provide ecosystem goods and services. Measurable indicators of ecosystem services, including broad and fine scale landscape indicators, were also distilled from a literature review. Thresholds/Learnings: Wetland cover should be maintained at >15% for watersheds with high potential for phosphorus loading & eutrophication. Impervious cover should be maintained at or below 25% in heavily urbanizing watersheds. Synopsis: This report develops a framework for assessing the condition of Southern Alberta’s natural assets and their resulting ability to provide ecosystem goods and services. The...
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Synopsis: Wind erosion control is typically needed in areas with low and variable precipitation and frequent droughts, and where high winds, high temperature and consequent high evaporation are common conditions, such as in southern Alberta. Potential average annual erosion rates from wind erosion are predicted using the wind erosion equation E= f(I, K, C, L, V) where I is the soil erodibility index, K is the soil-ridge-roughness factor, C is the climactic factor, L is the unsheltered, weighted travel distance of the wind across a field and V is the equivalent vegetated cover. Wind erosion can be controlled with one or more of the following five basic principles of wind erosion control: · Reduce field widths...
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Conclusions: Caribou subpopulation persistence and landscape occupancy depends highly on the degree of forest cover, cover type, and distance from human presence. Thresholds/Learnings: Synopsis: This study evaluates factors influencing the persistence and landscape occupancy of caribou subpopulations in southern British Columbia. Data from 235 radio-collared caribou across 13 subpopulations were used to derive a landscape occupancy index. The index was analyzed against 33 landscape variables including, land cover, terrain, climate, and human influence. At the metapopulation level, the persistence of subpopulations correlated with the extent of wet climate conditions and the distribution of old forests and alpine...
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Synopsis: Reviews information on grassland bird habitat requirements including a focus on the importance of grassland cover, size of contiguous patches, and other landscape factors. Some species require large blocks of unbroken grassland habitat for nesting. In general, where large blocks of undisturbed grassland occur, grassland birds are able to fulfill most of their requirements during the nesting season. For many bird species, these habitats provide winter and migration cover as well. The more grassland available in an area, particularly in large unbroken blocks, the greater the number of area-sensitive grassland birds the area is able to support. Pastures and crop fields also often provide attractive cover...
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Synopsis: Recent reports clearly indicate that odor emitted from concentrated livestock production facilities in the Midwest of the US is a significant social problem that negatively impacts rural and state economies, human health, and the quality of rural life. A potential incremental approach to dealing with livestock odor is the use of shelterbelts arranged in strategic designs near and within livestock facilities. This review outlines the various ways that shelterbelts can be effective technology which biophysically mitigates odor thereby reducing social conflict from odor nuisance. The biophysical potential of shelterbelts to mitigate livestock odor arises from the tree/shrub impacts on the central characteristics...
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Synopsis: Remotely sensed data and GIS were used to compare the effects of clear-cutting and road-building on the landscape pattern of the Bighorn National Forest, Wyoming. Landscape patterns were quantified for each of 12 watersheds on a series of four maps that differed only in the degree of clear-cutting and road density. Researchers analyzed several landscape pattern metrics for the landscape as a whole and for the lodgepole pine and spruce/fir cover classes across the four maps to determine the relative effects of clear-cutting and road building on the pattern of each watershed. At both the landscape and cover class scales, clear-cutting and road building resulted in increased fragmentation as represented...


map background search result map search result map Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Minimum habitat requirements for establishing translocated cutthroat trout populations. Ecosystem Goods and Services Southern Alberta Assessment of Natural Asset Condition Flood reduction through wetand restoration: the Upper Mississippi River Basin as a case history. Effects of land cover change on streamflow in the interior Columbia River Basin (USA and Canada). Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. Grassland Birds Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest Olive-backed Pocket Mouse. Partners in Flight Bird Conservation Plan for Northern Mixed-Grass Prairie Basic principles of wind erosion control Mitigating swine odor with strategically designed shelterbelt systems: a review. Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. Olive-backed Pocket Mouse. Minimum habitat requirements for establishing translocated cutthroat trout populations. Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Ecosystem Goods and Services Southern Alberta Assessment of Natural Asset Condition Partners in Flight Bird Conservation Plan for Northern Mixed-Grass Prairie Flood reduction through wetand restoration: the Upper Mississippi River Basin as a case history. Effects of land cover change on streamflow in the interior Columbia River Basin (USA and Canada). Grassland Birds Basic principles of wind erosion control Mitigating swine odor with strategically designed shelterbelt systems: a review.