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Conclusions:Wetlands and riparian zones should be strategically placed in watersheds to optimize nitrogen removal, as, for example, in tile-drained farmlands prone to high concentrations of nitrateThresholds/Learnings:Restoring 10 million hectares of riparian zones and wetlands, representing 3.4% of the Mississippi River basin, would reduce nitrogen in the Mississippi River Basin and its tributaries by an average of 40%
Conclusions:Report presents draft outcomes, indicators, and targets for the Red Deer River Basin in three topic areas: wetlands, riparian areas, and land use. Targets established were based on a detailed literature review, combined with Geographic Information Systems (GIS) queries of existing conditions.Thresholds/Learnings:Specific thresholds for the region include: wetland cover should comprise >7.5% of the watershed; peatland cover should comprise > 6.0% in the upper headwaters; 82% of all riparian areas (variable width) in the watershed should have perennial vegetation cover; 97% of all riparian areas (variable width) in the Upper Headwaters should have perennial vegetation cover
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Conclusions: Habitat changes resulting from timber harvest have altered the predator–prey balance leading to asymmetric predation affecting the survivial rates of endangered mountain caribou Thresholds/Learnings: As young forest stands increase in proportion to old forests, caribou population densities and survival rates decline as they become increasingly vulnerable to predation and extripation. Synopsis: Timber harvesting in areas of Mountain Caribou habitat have created landscapes of early seral forests. Such habitat changes have altered the predator–prey balance resulting in asymmetric predation in which predators are maintained by alternative prey (i.e. apparent competition). This study estimates survival...
Conclusions:Wetlands were found to work best, in terms of providing ecosystem services, as spatially distributed systems. Wetland value was also found to be highly depended on its hydrogeomorphic position in the landscape relative to other landscape features and human settlements. Wetlands should comprise 3-7% of temperate watersheds for flood control and improved water qualityThresholds/Learnings:Wetlands should comprise 3-7% of temperate watersheds for flood control and improved water quality
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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: 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...
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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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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: Researchers measured the effects of grassland amount and fragmentation on upland and wetland songbird and duck densities and nest success across 16 landscapes in southern Alberta. By comparing these landscape-level effects with local-scale responses, including distance to various edges and vegetation characteristics, the study demonstrated that few species were in fact influenced by grassland amount or fragmentation. In contrast, distance to edge and local vegetation characteristics had significant effects on densities and nest success of many species. Landscape level effects were much less apparent when local characteristics were included in the models. Therefore, researchers concluded that local habitat...
Conclusions:distance from edge and the habitat heterogeneity were the most important variables affecting bryophyte and lichen species richnessThresholds/Learnings:Temperature and light intensity decreased, and humidity increased up to 15m from the edge of fragments in the study.
Conclusions:Landscape features affect rates of brood parasitism. Rates of parasitism correlate with proximity to woody vegetation along patch edges. Influx of woody vegetation is associated with roadsides and grazing.Thresholds/Learnings:
Conclusions:Severe fire regimes create essential habitat conditions for certain habitat specialists.Thresholds/Learnings:
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Synopsis: Recensuses of 54 Wisconsin prairie remnants showed that 8 to 60 percent of the original plant species were lost from individual remnants over a 32- to 52-year period. The pattern of species loss was consistent with the proposed effects of fire suppression caused by landscape fragmentation. Short, small-seeded, or nitrogen-fixing plants showed the heaviest losses, as did species growing in the wettest, most productive environments. The interruption of landscape-scale processes (such as wildfire) by fragmentation is an often overlooked mechanism that may be eroding biodiversity in many habitats around the world. Conclusions: Fragmentation may interrupt landscape-scale processes, such as fire, that are key...
Conclusions:Water chemistry parameters sampled in downstream reaches were most closely correlated with riparian land cover adjacent to the smallest (first-order) streams of watersheds or land use in the entire watershed, with riparian zones immediately upstream of sampling sites offering less explanatory power as stream size increased.Thresholds/Learnings:
Synopsis: This paper aimed to quantify the relative importance of habitat area and configuration, as well as the contrast in resistance between habitat and non-habitat, on genetic differentiation patterns. Using spatially explicit, individual-based simulation modeling, researchers found that habitat configuration had stronger relationships with genetic differentiation than did habitat area. The pattern of habitat in a landscape will affect the distribution of the population and the degree of connectivity across it, resulting in differential patterns of gene flow. Researchers also evaluated the predictive ability of six widely used landscape metrics and found that patch cohesion and correlation length of habitat...
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Conclusions: Elevation, slope and the percentages of bogs and fens in a landscape influence the degree to which mid-boreal lakes are sensitive to acidic deposition orignating from nearby mining operations. Thresholds/Learnings: Synopsis: This study evaluates the acid sensitivity of lakes in Saskatchewan within ~300km of Fort McMurray. The study area is downwind of atmospheric emissions sources from regional oil sands mining operations and there is concern that the lakes may be threatened by acidification. A helicopter sampling program was implemented in late September 2007 and 2008 to measure 16 chemical variables (e.g., Ca, Mg, Na, pH) and 15 environmental variables (e.g., latitude, elevation, slope, percent bog,...
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Synopsis: This study investigates the relationships of landscape disturbance, altered prey resources, and rattlesnake populations in the Upper Snake River Plain of southeastern. Researchers used radio telemetry to track rattlesnakes while concurrently conducting habitat sampling and small mammal trapping in areas used by snakes and in random locations. Disturbed areas (by grazing and/or burning) were characterized by lower biological crust cover, shrub cover, shrub height, and shrub dispersion, as well as higher grass and bare soil cover. Disturbed areas were also characterized by lower proportions of small animal biomass, abundance, and large prey species (such as chipmunks), while the proportions Conclusions:...
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Synopsis: A review of the scientific literature describing the effects of linear developments on wildlife, especially large mammals, was provided. Of particular interest were the types of roads and linear developments created by the oil and pipeline industries in western Canada. The effects of linear developments (roads, powerline/pipeline rights-of-way, deforested strips) on wildlife were examined in the context of regional and landscape ecology. The review describes the different classes of linear disturbances, the various response categories for animal species and the impacts on species for the different classes. The review also provides potential mitigations and recommendations for landscape scale planning...
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Synopsis: Recognizing that natural and human disturbances cause significant changes to landscape composition and ecosystem function, this report aims to identify and describe key indicators of environmental sustainability, categorized by vegetation, biodiversity, and watershed characteristics. Measurable indicators of environmental sustainability, including landscape indicators summarized in the vegetation indicators category, were distilled from a wide-ranging literature review. These indicators are intended to serve as metrics of environmental quality that assist land use planners in determining if management goals have been reached. As such, the report provides an overview, assessment, and recommended uses for...
Synopsis: One recent study examining Eurasian watermilfoil (Myriophyllum spicatum L., hereafter milfoil) invasions using landscape-level variables found that the amount of forest land cover in the catchment is consistently negatively related to milfoil presence (Buchan and Padilla, 2000). These results suggest that further research is needed to examine the relationships between natural and anthropogenic landscape features and macrophyte cover. The ability of lake and landscape features to predict a variety of macrophyte cover metrics using 54 north temperate lakes were examined. Univariate regression analyses demonstrated that these macrophyte cover metrics are predicted by a wide range of predictor variables, most...
map background search result map search result map Chemical characteristics and acid sensitivity of boreal headwater lakes in northwest Saskatchewan. Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Changes in landscape composition influence the decline of a threatened woodland caribou population Grassland Birds Linking landscape disturbance to the population ecology of Great Basin rattlesnakes (Crotalus oreganus lutosus) in the Upper Snake River Plain Landscape, Biodiversity, and Indicator Review and Assessment Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest The Effects of Linear Developments on Wildlife: A Review of Selected Scientific Literature Ecological determinants of species loss in remnant prairies. Mitigating swine odor with strategically designed shelterbelt systems: a review. A multi-scale analysis of avian response to habitat amount and fragmentation in the Canadian dry mixed-grass prairie. A multi-scale analysis of avian response to habitat amount and fragmentation in the Canadian dry mixed-grass prairie. Chemical characteristics and acid sensitivity of boreal headwater lakes in northwest Saskatchewan. Ecological determinants of species loss in remnant prairies. Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Changes in landscape composition influence the decline of a threatened woodland caribou population Landscape, Biodiversity, and Indicator Review and Assessment Linking landscape disturbance to the population ecology of Great Basin rattlesnakes (Crotalus oreganus lutosus) in the Upper Snake River Plain The Effects of Linear Developments on Wildlife: A Review of Selected Scientific Literature Grassland Birds Mitigating swine odor with strategically designed shelterbelt systems: a review.