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Synopsis: This study evaluates whether previous observations of a higher percentage of parasitism and parasitoid diversity in a complex agricultural landscape, relative to a simple landscape, represent a general phenomenon. Rates of parasitism and parasitoid diversity of the armyworm (Pseudaletia unipuncta) were assessed in three replicate (Onondaga, Ingham, and Benton) regions in southern Michigan. Within each region, a simple landscape (primarily cropland) and a complex landscape (cropland intermixed with mid and late successional noncrop habitats) were identified through analysis of aerial photographs. In each landscape, three maize fields were selected, and second to fourth instar P. unipuncta were released...
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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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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...
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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This report is synthesizes and summarizes major findings from literature relating to the direct and indirect ecological impacts of paved highways on birds. It represents a meta-analysis of contributing factors of road mortality, effects of roadway lighting, traffic noise, traffic volume, and roadway contaminants on bird populations, which may help guide conservation efforts within the Yellowstone to Yukon ecoregion. Traffic volume and noise are believed to be the most important factors affecting breeding bird population densities near roads. The number of affected species increases with traffic volume but the relationship appears to reach threshold at an average daily traffic volume of 30,000 vehicles a day. In...
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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: 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.
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...
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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...
Conclusions:High proportions of native grass and low proportions of shrub cover are critical habitat components for maintaining viable sharp tailed grouse populations. *Note that this study generated landscape level models with coarse variables, and the thresholds and values used may not be directly applicable to other areas or for site-specific analysis.Thresholds/Learnings:Ideal shrub cover ranges from 5% to 15% and the ideal proportion of native grassland cover is >75% for sharp-tailed grouse*.
Conclusions:Report summarizes studies on the impacts of agricultural land use on water quality within Alberta. The impacts of agricultural activities on water quality depend strongly on the amount and distribution of land under cultivation, as well as other measures of agricultural intensity such as fertilizer expenses, chemical expenses and animal unit densities. Generally, streams draining watersheds with more agriculture had higher concentrations of nutrients, bacteria, and pesticides.Thresholds/Learnings:
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Synopsis: Wind erosion is considered a problem when the erosion level exceeds the tolerable limit for the soil or when the erosion level is great enough to damage the crops being grown. Wind erosion control must be tailored to each farming situation and may be achieved through a combination of practices that ultimately create isolated fields, the key to wind erosion control systems. Wind erosion control measures can be grouped into four components: (1) tree and shrub windbreaks; (2) annual and perennial vegetative barriers; (3) strip cropping and trap strips; and (4) crop residues and cover crops. Wind control system design involves 4 basic principles: (1) erosion rates are predicted using the wind erosion equation;...
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Synopsis: Agricultural intensification and expansion are major present and future causes of global ecosystem disruption. Natural and semi-natural reserve areas in agroecosystems are thought to be important for preservation of essential ecosystem services such as pollination, but data about land use patterns and pollinator abundance are lacking. We assessed wild bee populations in canola fields in an agriculturally intense area where virtually all land was either tilled agricultural fields or semi-natural grazed pasturelands, with the expectation that mosaics of land use types may better support ecosystem services than homogenous crop areas. Fields were chosen in two categories, five with little or no pastureland...
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Conclusions: Report identifies regional patterns of habitat disturbance, land use practices, and population trends relative to greater sage-grouse. In general, the most important landscape characteristics influencing sage-grouse populations are the proximity of leks (areas in which males perform to nesting habitat for and The report examined findings from studies that indicate several area and distance specific conservation thresholds for maintaining viable sage-grouse habitat. Thresholds/Learnings: Male sage-grouse prefer sod-forming grasses or bare ground for leks; female sage-grouse prefer dense sagebrush stands surrounding leks for nesting; gentle terrain characterized by <10% slope; <5% of existing sagebrush...
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Synopsis: Windbreaks are a major component of successful agricultural landscapes. At the farm scale, they help control erosion and blowing snow, improve animal health and survival under winter conditions, reduce energy consumption of the farmstead, and enhance habitat diversity. At a landscape scale, they provide habitat for various types of wildlife and have the potential to contribute significant benefits to the carbon balance equation, thereby easing the economic burdens associated with climate change. The effectiveness of a windbreak is determined partially by its external structure including its height, length, orientation, continuity, width, and cross-sectional shape and partially by its internal structure...


map background search result map search result map Effects of paved roads on birds: a literature review and recommendations for the Yellowstone to Yukon Ecoregion 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 Conservation Assessment of Greater Sage-Grouse and Sagebrush Habitats Landscape, Biodiversity, and Indicator Review and Assessment Does agricultural landscape structure affect parasistism and parasitoid diversity? Can pastureland increase wild bee abundance in agriculturally intense areas? Partners in Flight Bird Conservation Plan for Northern Mixed-Grass Prairie Windbreaks in North American Agricultural Systems Basic principles of wind erosion control Design and use of field windbreaks in wind erosion control systems 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. Does agricultural landscape structure affect parasistism and parasitoid diversity? A multi-scale analysis of avian response to habitat amount and fragmentation in the Canadian dry mixed-grass prairie. Minimum habitat requirements for establishing translocated cutthroat trout populations. Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Ecosystem Goods and Services Southern Alberta Assessment of Natural Asset Condition Landscape, Biodiversity, and Indicator Review and Assessment Partners in Flight Bird Conservation Plan for Northern Mixed-Grass Prairie Conservation Assessment of Greater Sage-Grouse and Sagebrush Habitats Effects of paved roads on birds: a literature review and recommendations for the Yellowstone to Yukon Ecoregion Windbreaks in North American Agricultural Systems Basic principles of wind erosion control Design and use of field windbreaks in wind erosion control systems Mitigating swine odor with strategically designed shelterbelt systems: a review.