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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Invasions in the Prairie Pothole Region: Addressing the Effects of Exotic Plants on Wetland and Grassland Ecosystems and Restoration Efforts

Durant, Cheyenne Elizabeth January 2020 (has links)
Three wetland restoration methods: seeding, seeding + hay mulch, and seeding + hay mulch + vegetation plugs were compared via the plant community within a formerly cropped wetland in southeastern North Dakota. Arrangement of plugs were also compared to assess the success of native species establishment. Mean relative cover for native species and introduced species were recorded and analyzed to compare the restoration methods and plug arrangement. Three herbicide treatments were studied on upland prairie sites with and without prescribed burning to test effects on leafy spurge (Euphorbia esula) control and seeded native establishment. There is no difference native species richness between the restoration methods six years post restoration, and no difference in plant cover in the different arrangement of plugs. Quinclorac significantly reduced leafy spurge cover; however, glyphosate treatments had higher cover of seeded native species.
22

Transformation of Chlorpyrifos and Chlorpyrifos-Methyl in Prairie Pothole Pore Water

Adams, Rachel May 21 May 2015 (has links)
No description available.
23

The use of riparian health assessments to assess cumulative anthropogenic effects to wetlands in the Prairie Pothole Region of Saskatchewan

2016 March 1900 (has links)
Wetlands are significant contributors to global biodiversity, supporting disproportionately high numbers of species relative to their area. Riparian areas associated with wetlands provide many services that are both ecologically and economically important, such as groundwater recharge, sediment capture and shoreline stabilization, flood mitigation, nutrient processing, increased water quality, carbon sequestration, and essential habitat for wildlife. Agricultural activity has resulted in the drainage or modification of between 40-70% of wetland basins within the Prairie Pothole Region of the northern Great Plains. The impacts of human activity on the remaining wetlands are difficult to estimate and there is no one optimal indicator or assessment method that is applicable to all regions or situations. Locally developed riparian health assessments, designed to evaluate wetland function under different grazing regimes, are cost-effective with the potential for broader use in wetland environmental assessment, monitoring, and management or restoration activities. In this study I investigated the hypothesis that riparian health assessments can distinguish between wetlands in five categories of land use that represent different levels of anthropogenic modification: ungrazed cultivated cropland, ungrazed native grassland, grazed native grassland, ungrazed tame perennial forage, and grazed tame perennial forage. Noting that current riparian health assessment protocols lack a community composition component other than the presence and distribution of invasive and disturbance species, I also sampled plant species frequency at each of my study sites. I found that wetlands in cultivated croplands had significantly lower riparian health scores than wetlands in both tame and native grasslands. Among tame and native sites, grazing status was more important than upland cover type in determining wetland health, with grazed wetlands receiving significantly lower scores than their ungrazed counterparts. Despite their functional similarity to wetlands within native grasslands, species composition of wetlands within ungrazed tame perennial forage more closely resembled that of wetlands in cultivated uplands. Although grazing negatively affected riparian ground cover and soil stability, it significantly reduced both the overall cover and distribution of invasive plant species along wetland reaches. These results suggest that upland revegetation and restoration of function to degraded wetlands is not necessarily followed by re-establishment of original riparian species composition. If biodiversity is a desired outcome of wetland restoration efforts, additional measures must be taken to enable the establishment and persistence of preferred plant species.
24

Mallard duckling survival and habitat selection in the Canadian prairie pothole region

Bloom, Pauline Marion 10 May 2010
Like life-history theory, wildlife management decisions are typically predicated on trade-offs between benefits associated with investing resources to achieve higher reproductive or survival rates versus costs or risks of achieving those goals. On the Canadian prairies, most waterfowl conservation resources are directed to policies and programs that seek to increase duck nesting success. Limited attention has focused on post-hatching life-cycle stages, yet, despite considerable recent work on duckling survival rates, many uncertainties remain concerning how abiotic and biotic factors affect duckling survival rates. The role of upland habitat characteristics may be important but has received limited attention. I evaluated hypothesized sources of variation in duckling survival for 617 mallard (Anas platyrhynchos) broods on 27 Canadian prairie-parkland sites, with emphasis on assessing effects of managed and remnant natural upland habitats. I contrasted suites of a priori and post hoc exploratory models that incorporated effects of landscape, weather, female and brood-related variables to explain variation in duckling survival rates. Survival was lower for ducklings that used areas with high proportions of semi-permanent wetlands, as well as for broods that travelled farther overland. Exploratory analyses revealed further that survival of ducklings was negatively related to the amount of managed hayland. In contrast, duckling survival was positively associated with the amount managed grassland. There was no evidence of trade-offs between benefits of managing habitat to enhance duck nesting success versus costs in terms of lower subsequent duckling survival.<p> I also addressed unresolved questions about how birds balance costs and benefits of selecting habitats by determining the survival consequences of habitat choices made during brood-rearing. In theory, fitness should be higher in preferred habitats, but this assumption is rarely tested. Fitness consequences (i.e., duckling survival) of habitat selection patterns were determined at landscape and local scales using logistic regression and information-theoretic model selection techniques. Best-approximating landscape-level models indicated that mallard females selected brood-rearing areas with a high proportion of wetland and perennial upland habitats, but duckling survival was not related to habitat selection patterns at this scale. At finer spatial scales, females selected brood-rearing areas with high proportions of wetland habitats, but, contrary to expectation, duckling survival was lower when females raised their broods in these areas. Females avoided areas with abundant perennial cover and wetlands with little vegetative cover and, consistent with prediction, duckling survival was higher when females selected areas with low perennial cover. Thus, females did not consistently select brood-rearing habitats that conferred the highest fitness benefits. Rather, the relationship between habitat selection and duckling survival depended on spatial scale and habitats considered.
25

Mallard duckling survival and habitat selection in the Canadian prairie pothole region

Bloom, Pauline Marion 10 May 2010 (has links)
Like life-history theory, wildlife management decisions are typically predicated on trade-offs between benefits associated with investing resources to achieve higher reproductive or survival rates versus costs or risks of achieving those goals. On the Canadian prairies, most waterfowl conservation resources are directed to policies and programs that seek to increase duck nesting success. Limited attention has focused on post-hatching life-cycle stages, yet, despite considerable recent work on duckling survival rates, many uncertainties remain concerning how abiotic and biotic factors affect duckling survival rates. The role of upland habitat characteristics may be important but has received limited attention. I evaluated hypothesized sources of variation in duckling survival for 617 mallard (Anas platyrhynchos) broods on 27 Canadian prairie-parkland sites, with emphasis on assessing effects of managed and remnant natural upland habitats. I contrasted suites of a priori and post hoc exploratory models that incorporated effects of landscape, weather, female and brood-related variables to explain variation in duckling survival rates. Survival was lower for ducklings that used areas with high proportions of semi-permanent wetlands, as well as for broods that travelled farther overland. Exploratory analyses revealed further that survival of ducklings was negatively related to the amount of managed hayland. In contrast, duckling survival was positively associated with the amount managed grassland. There was no evidence of trade-offs between benefits of managing habitat to enhance duck nesting success versus costs in terms of lower subsequent duckling survival.<p> I also addressed unresolved questions about how birds balance costs and benefits of selecting habitats by determining the survival consequences of habitat choices made during brood-rearing. In theory, fitness should be higher in preferred habitats, but this assumption is rarely tested. Fitness consequences (i.e., duckling survival) of habitat selection patterns were determined at landscape and local scales using logistic regression and information-theoretic model selection techniques. Best-approximating landscape-level models indicated that mallard females selected brood-rearing areas with a high proportion of wetland and perennial upland habitats, but duckling survival was not related to habitat selection patterns at this scale. At finer spatial scales, females selected brood-rearing areas with high proportions of wetland habitats, but, contrary to expectation, duckling survival was lower when females raised their broods in these areas. Females avoided areas with abundant perennial cover and wetlands with little vegetative cover and, consistent with prediction, duckling survival was higher when females selected areas with low perennial cover. Thus, females did not consistently select brood-rearing habitats that conferred the highest fitness benefits. Rather, the relationship between habitat selection and duckling survival depended on spatial scale and habitats considered.
26

Relationships between reduced sulfur and dissolved organic matter in prairie pothole wetlands

McAdams, Brandon C. 11 October 2017 (has links)
No description available.
27

Myth and mechanism: exhibiting the unexpected Saskatchewan landscape

Jukes, Vanessa 24 August 2012 (has links)
Through inquiry, experience, and discovery, this practicum reveals the landscape of Old Wives Lake, Saskatchewan and the prairie pothole region that surrounds it. It is my intention for this work to become a device for the revealing of unseen forces, for the creation of a different attention, an altering of perception, and an openness to a unique landscape of ever changing and shifting phenomena. It is accepted that complex systems, cannot be fully understood without time, patience, and commitment; however, through learning, understanding and revealing, the potential to not simply ‘see’ a landscape, but ‘read’ a landscape is harvested to enlighten and share in its discovery. The result is an exhibition of the unexpected Saskatchewan landscape.
28

Myth and mechanism: exhibiting the unexpected Saskatchewan landscape

Jukes, Vanessa 24 August 2012 (has links)
Through inquiry, experience, and discovery, this practicum reveals the landscape of Old Wives Lake, Saskatchewan and the prairie pothole region that surrounds it. It is my intention for this work to become a device for the revealing of unseen forces, for the creation of a different attention, an altering of perception, and an openness to a unique landscape of ever changing and shifting phenomena. It is accepted that complex systems, cannot be fully understood without time, patience, and commitment; however, through learning, understanding and revealing, the potential to not simply ‘see’ a landscape, but ‘read’ a landscape is harvested to enlighten and share in its discovery. The result is an exhibition of the unexpected Saskatchewan landscape.
29

Modeling the Suitability of Landscapes for Managed Honeybees - A Case Study in the Northern Great Plains

Kirkpatrick, Emma 27 July 2015 (has links)
No description available.
30

Vertical gardening in a northern city; speculations for Winnipeg

Urben-Imbeault, Tamara 26 May 2015 (has links)
This practicum is a reference for vertical gardeners in cold climates. Winnipeg, Manitoba is explored, however findings may be applied to other cities in similar climates. First, the history of vertical gardening is discussed, then the types of vertical gardens currently on the market are described. These can be classified into two categories: soil bearing or non-soil bearing. Most designs are modular pre-planted systems that can be attached to any wall, as long as it satisfies the structural requirements recommended by the manufacturer. The benefits of vertical gardening have been shown to be rather extensive, covering a wide range of areas. Aesthetic improvement, reduction of the Urban Heat Island (UHI) effect, improvement of air quality, stormwater absorption, noise reduction, native habitat integration, reduction of heating and cooling costs for buildings, food production, marketing, and biophilia are all benefits explored in detail. Difficulties associated with vertical gardening are discussed, specifically the lack of knowledge and awareness of vertical gardens, lack of empirical evidence (or missing details in existing research), overall cost and lack of financial incentives, lack of industry codes, and various associated risks. Design framework exists within microclimate conditions unique to vertical gardens, as well as neighbourhood and regional (micro)climates. Theories relating to the study of green walls covered include the human ecosystem model, urban reconciliation ecology, habitat templating, the urban cliff hypothesis, and wall ecology. Suitable habitat templates identified for vertical gardens in Winnipeg are cliffs, sand dunes, alvars, mixed grass prairie and prairie potholes. Design parameters to be followed for vertical garden design in Winnipeg are to ensure that lightweight materials are used, to provide insulation to protect plants from sudden temperature changes, to choose plants that grow in the region and are adapted to grow in areas with limited soil, increased wind, varying degrees of sunlight (depending on orientation), and increased pollution and salt spray depending on location. / October 2015

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