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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.
1

Mapping elk distribution on the Canadian prairies: Applying local knowledge to support conservation

2014 June 1900 (has links)
Once abundant across the Great Plains of North America, prairie-parkland elk (Cervus canadensis manitobensis) underwent a catastrophic population collapse and dramatic contraction of their overall range through the late 1800’s and the early 1900’s due to habitat loss (primarily from agricultural expansion) and unregulated hunting. Populations were able to recover in some areas following new hunting regulations and the establishment of protected areas. Prior to this study, the current distribution of prairie parkland elk was poorly understood, though it was established that they were largely relegated to large protected areas and made use of adjacent agriculture dominated landscapes. In order to effectively manage prairie-parkland elk so populations remain resilient to ongoing habitat loss, population reduction and disease risks, detailed mapping of their range and an understanding of the environmental factors most important to elk is essential. The purpose of my thesis is to characterize elk distribution and resource selection patterns in the prairie-parkland of Saskatchewan and Manitoba, Canada, at a landscape scale and assess the implications of distribution for species persistence, by using both local ecological knowledge (LEK) and biological research techniques in tandem. Integrating LEK with more conventional biological research can provide complementary data at contrasting time and spatial scales and facilitates comparison of multiple independent datasets. Furthermore, LEK research creates important opportunities to engage stakeholders in contributing knowledge and may facilitate relationships and contribute toward more effective resource management. I used three sets of biotelemetry-collar data from across Saskatchewan and Manitoba (n = 328 collared elk; 1998–2012), in conjunction with LEK from hunters, biologists and enforcement officers (n = 71 participants) to create a series of resource selection functions (RSFs) characterizing elk distribution across Saskatchewan and Manitoba. I gathered LEK in workshops where participatory mapping was conducted with local experts across the study area. The RSF analysis determined that prairie-parkland elk selected locations close to protected areas and far from high road density. Elk also selected areas with moderate amounts of mixed-wood and deciduous forests and herbaceous vegetation. Models developed with LEK only, biotelemetry collar data only and a combined dataset were all validated against an independent dataset of elk crop damage locations. All models predicted elk presence well. The RSF scores of the LEK only and radio-collar only models were not significantly different. Successful conservation management requires identifying which areas are most important to a species, and assessing if these areas are vulnerable to threats, as well as balancing human resource needs. Using the RSF-based maps of prairie-parkland elk distribution, I identified locations of high quality habitat (top 10% of RSF values) and determined which of those areas were vulnerable to agricultural expansion, forestry, disease, and hunting. I identified 81 high quality habitat areas with a combined total area of 30 753 km2. One or more vulnerability factor impacted 87% of the identified core area. High quality areas were clearly clustered around the boreal-prairie transition zone and large protected areas. The majority (88%) of high quality core areas were located within protected areas. A connectivity analysis using least cost path analysis determined that core habitat areas endemic with chronic wasting disease (CWD) in wild elk are highly connected to other high quality habitat areas. CWD thus has the potential to reduce cervid populations within the study area. My thesis results highlight that prairie-parkland elk populations in Saskatchewan and Manitoba remain threatened by habitat loss and disease, and emphasize the need for habitat conservation to prevent further population reduction. While elk populations have regained a small fraction of the range lost at the turn of the last century, they have not been able to re-establish with much success in the prairie portion of their range. I also determined that LEK can be as effective as conventional biological research approaches to develop RSFs. I also confirmed that stakeholders within the study are knowledgeable about elk behaviour. The distribution maps and identified areas of priority concern created in this thesis can provide important insights to support the management and maintenance of abundant elk populations.
2

Influence de l'intensification agricole et de la sélection de proies des parents sur la diète des oisillons chez l'Hirondelle bicolore (Tachycineta bicolor)

Bellavance, Véronique January 2014 (has links)
L’anthropisation est un phénomène mondial qui affecte plusieurs taxa qui se retrouvent dans des milieux variés, autant terrestres qu’aquatiques. Même si, pour quelques espèces, ces changements sont bénéfiques, pour la plupart d’entres-elles ils entrainent des conséquences désastreuses pouvant mener au déclin de leurs populations. L’avifaune insectivore aérienne champêtre n’est pas épargnée par ce phénomène puisque la détérioration des aires de reproduction par l’intensification des pratiques agricoles a participé, de manière non équivoque, au déclin de cette faune. En effet, plusieurs études ont montré des effets négatifs de l’intensification agricole sur certains traits d’histoire de vie de ses oiseaux (p. ex. : diminution de la croissance et du succès reproducteur chez les oiseaux de milieux intensifs vs milieux extensifs). Afin d’expliquer ces effets, l’hypothèse la plus souvent suggérée se base sur le fait que dans les milieux agricoles intensifs où des insecticides sont utilisés, la disponibilité en insectes est inférieure aux milieux naturels. Donc, par l’entremise d’une diminution en abondance et en diversité d’insectes disponibles dans les milieux agricoles, la diète des oiseaux est affectée ce qui peut potentiellement participer au déclin des insectivores aériens. Or, peu d’études ont tenté de déterminer la diète d’un insectivore aérien champêtre en déclin dans les milieux agricoles ou ont tenté de déterminer les variables qui peuvent influencer sa sélection de proies, changeant potentiellement la composition même de la diète. Sachant que 1) la diète insectivore est influencée par la disponibilité de proies dans le milieu; que 2) la disponibilité de proies est influencée par l’environnement (paysage, conditions météorologiques et temporelles, etc.); et que 3) les stratégies de quête alimentaire de l’insectivore aérien (fréquence et durée des quêtes, nombre de proies capturées, stratégies de sélection et d’évitement de proies, etc.) fluctuent et dépendent de la disponibilité de proies dans l’environnement et de l’environnement lui-même, je me suis intéressée, dans ce mémoire, aux fluctuations dans la sélection de proies d’un insectivore aérien, selon différentes variables. Plus particulièrement, je me suis intéressée à l’effet de l’intensification agricole, de la disponibilité de proies dans les milieux agricoles, de la condition morphologique de la femelle, de l’état de sa niché et des conditions environnementales et temporelles sur la sélection de proies d’un insectivore aérien en déclin. Ainsi, dans cette étude, des becquées alimentaires ont été récoltées chez l’Hirondelle bicolore (Tachycineta bicolor), passereau insectivore aérien en déclin dans le Nord-Est de l’Amérique du Nord depuis plus de 25 ans, puis comparées à des échantillons d’insectes disponibles, tous deux récoltés le long d’un gradient d’intensification agricole dans de Sud du Québec. Mes résultats montrent d’abord que les diptères représentent l’ordre le plus important dans la diète de l’Hirondelle bicolore et supportent l’idée d’un effet négatif de l’intensification des pratiques agricoles sur l’abondance en arthropodes disponibles dans le milieu. Par ailleurs, j’ai également montré que les associations entre les composantes du paysage agricole et certains taxa d’insectes étaient différentes entre les becquées et les pièges à insectes, suggérant une potentielle sélection de proies de la part des hirondelles. J’ai finalement déterminé les variables qui affectent le plus fortement la sélection de diptères par l’Hirondelle bicolore, c’est-à-dire la disponibilité de diptères dans le milieu, l’intensification agricole et la date de récolte des échantillons et ce, contrôlé pour des variables météorologiques et temporelles confondantes Cette étude est, jusqu’à présent, la plus développée et complète sur ce sujet tant au niveau de la couverture spatio-temporelle qu’au niveau de l’ampleur de l’échantillonnage qui aboutit en une base de données inégalée De plus, seule l’approche statistique complexe réalisée dans le cadre de cette étude permet d’adéquatement caractériser les déterminismes de la sélection de proies qui visent à comprendre une réponse comportementale potentielle de l’insectivore aérien face à des pressions au niveau des proies lui étant disponibles dans les milieux agricoles causée par l’intensification des pratiques agricoles.
3

Conserving cougars in a rural landscape: habitat requirements and local tolerance in west-central Alberta

Knopff, Aliah Adams Unknown Date
No description available.
4

Conserving cougars in a rural landscape: habitat requirements and local tolerance in west-central Alberta

Knopff, Aliah Adams 06 1900 (has links)
Maintaining large carnivores in human-dominated landscapes poses a significant conservation challenge. Extirpation is common because of habitat loss or direct persecution. I studied cougar habitat selection and human perception of cougars in west-central Alberta to better understand human-cougar coexistence. Cougars that were exposed to higher levels of development at the home-range scale exhibited less avoidance of anthropogenic features and altered habitat use temporally to accommodate variation in human activity, indicating behavioral resilience to development. Survey results showed that cougars were valued and tolerated by people, provided cougars did not occur near residences. Where human densities are increasing in moderately developed landscapes in west-central Alberta, therefore, human tolerance may currently be more important than habitat change for conserving cougar populations. Tolerance was negatively affected primarily by the risk (real and perceived) cougars pose to people, livestock, and game. Public education to counteract overestimation of risk may increase tolerance. / Ecology
5

Tillvaratagande av möjligheter med ledningsstödssystem inom teknisk tjänst.

Karlsson, Sebastian January 2016 (has links)
Nya ledningsstödsystem är under införande inom Försvarsmakten. För förband som verkar inom teknisk tjänst innebär detta nya förutsättningar för att lösa sina uppgifter. Studien syftar till att undersöka hur väl de ledningsstödssystem som är under införande är anpassade till verksamhetens krav inom Teknisk Bataljon och vilka förändringar som bör göras för att få en klok systemlösning. Styrande dokument inom teknisk tjänst har studerats och personer verksamma inom Teknisk Bataljon och Forsvarets Forskningsinstitutt har intervjuats. Tekniskt finns det förutsättningar för att arbeta effektivt, men idag används flera olika system parallellt. Det är på fältet svårt att ha en gemensam teknisk lägesbild, där särskilt överblick av reservdelar och materiell status är viktigt. Det största hindret för detta är förmågan att i samma system verka mellan förband då transmissionsresurser kan vara olika eller saknas. Säkerhetskrav och förmågan att verka med andra nationer utgör även dessa hinder för att verka effektivt både nationellt och internationellt. Studien pekar på att systeminförandet inte kommer att leda till gynnsammast möjliga effekter då detta inte sker på tillräcklig nivå, eller är koncentrerat till ett system, för att lyckas med detta. Effektivare ledningsstödsystem möjliggör lättare och därmed rörligare tekniska förband. En klok implementering skulle ha både verksamhetsrationella och kostnadseffektiva vinster. / New Command and Control Support systems are being introduced within the Swedish Armed Forces. Military maintenance units are therefore presented with new conditions. This study aims to evaluate how well this implementing of systems is adapted to said organizations and what should be done to further improve the effects of this change. Directorial documents are studied and active personnel are interviewe to provide data for this study. There are technical solutions to put in place an effective use of maintenance units and today there are several systems used side by side. Sensemaking is hard to achieve on the field, in particular with important items like spare parts and technical systems. The largest hindrance is within transmission resources and common transmission system, which are sometimes different and sometimes absent. Information security and capability to exchange information with other nations restricts operational effect, both nationally and internationally. This study suggests that the implementation will not reach optimum effect since the changes doesn’t reach low enough within the organization, or are focused on a single system to achieve maximum effect. More effective Command and Control systems enable more mobile maintenance units. A wise implementation will lead to both rational operations and economical efficiency.
6

Woodland Caribou Conservation in Alberta: Range Delineation and Resource Selection

Slater, Simon C Unknown Date
No description available.
7

Sclerocactus wrightiae (Cactaceace): An Evaluation of the Impacts Associated with Cattle Grazing and the Use of Remote Sensing to Assess Cactus Detectability

Bates, Thomas Hathaway 20 April 2020 (has links)
The Wright fishhook cactus (Sclerocactus wrightiae L.D. Benson) is an endangered cactus species endemic to south-central Utah. Since its listing in 1979 by the U.S. Fish and Wildife Service, the potential impacts of soil disturbance by cattle have become a central focus of management policies and monitoring efforts. However, little to no empirical data has been collected to substantiate the hypothesis that soil disturbance by cattle has direct or indirect negative effects on Wright fishhook cactus growth or reproduction. Over the years, the Bureau of Land Mangement (BLM) and Capitol Reef National Park (CRNP) have invested significant resources documenting cactus populations including several attributes of individual cacti: GPS location, diameter, number of flowers, fruits, or buds, number of stems, and the presence or absence of a cow track within 15 cm of the cactus. While these efforts have been commendable, due to the defining phenological characteristics of this species (flower and filament color) and its short flowering period (April-May) it remains difficult to study and much basic biological information including a range wide population estimate and defined critical habitat remain unknown. Our research had two primary objectives, 1) evalutate the effects of soil disturbance by cattle on reproduction and diameter of the Wright fishhook cactus (Chapters 1 and 2), and 2) explore the use of drones and GIS to define critical habitat and obtain an accurate range wide population estimate (Chapters 3 and 4). In Chapter 1, we analyzed cactus attribute data collected by the BLM at 30 macro-plots representing different levels of soil related cattle disturbance (high, moderate, and low) from 2011-2017. We found no significant association between level of cattle disturbance and flower density or cactus diameter. We did find a significant negative association between flower frequency and increased disturbance. In Chapter 2, we conducted an experimental study where tracks were simulated within 15 cm of cacti at various levels (Ctrl, 1-Track, 2-Track, 4-Tracks, and 4-Tracks Doubled). No significant association was observed between the number of tracks and response in diameter, flower production, fruit production, or seed set. In Chapter 3, we conducted drone flights over 14 macro-plots at three different altitudes above ground level (10 m, 15 m, and 20 m) and found that while the 10 m flights provided the best remotely sensed survey results, drones are not a suitable replacement for ground censuses. In Chapter 4, we used Resource Selection Function to define critical habitat for the Wright fishhook cactus. Our modeling suggests that geology, elevation, and slope are significant factors in defining cactus habitat. Based on the results of our research we conclude that soil disturbance by cattle may not have a significant influence on Wright fishhook cactus populations or dynamics, and that accurate range wide population estimates may be best obtained through ground surveys within the predicted critical habitat.
8

Sclerocactus wrightiae (Cactaceace): An Evaluation of the Impacts Associated with Cattle Grazing and the Use of Remote Sensing to Assess Cactus Detectability

Bates, Thomas Hathaway 20 April 2020 (has links)
The Wright fishhook cactus (Sclerocactus wrightiae L.D. Benson) is an endangered cactus species endemic to south-central Utah. Since its listing in 1979 by the U.S. Fish and Wildife Service, the potential impacts of soil disturbance by cattle have become a central focus of management policies and monitoring efforts. However, little to no empirical data has been collected to substantiate the hypothesis that soil disturbance by cattle has direct or indirect negative effects on Wright fishhook cactus growth or reproduction. Over the years, the Bureau of Land Mangement (BLM) and Capitol Reef National Park (CRNP) have invested significant resources documenting cactus populations including several attributes of individual cacti: GPS location, diameter, number of flowers, fruits, or buds, number of stems, and the presence or absence of a cow track within 15 cm of the cactus. While these efforts have been commendable, due to the defining phenological characteristics of this species (flower and filament color) and its short flowering period (April-May) it remains difficult to study and much basic biological information including a range wide population estimate and defined critical habitat remain unknown. Our research had two primary objectives, 1) evalutate the effects of soil disturbance by cattle on reproduction and diameter of the Wright fishhook cactus (Chapters 1 and 2), and 2) explore the use of drones and GIS to define critical habitat and obtain an accurate range wide population estimate (Chapters 3 and 4). In Chapter 1, we analyzed cactus attribute data collected by the BLM at 30 macro-plots representing different levels of soil related cattle disturbance (high, moderate, and low) from 2011-2017. We found no significant association between level of cattle disturbance and flower density or cactus diameter. We did find a significant negative association between flower frequency and increased disturbance. In Chapter 2, we conducted an experimental study where tracks were simulated within 15 cm of cacti at various levels (Ctrl, 1-Track, 2-Track, 4-Tracks, and 4-Tracks Doubled). No significant association was observed between the number of tracks and response in diameter, flower production, fruit production, or seed set. In Chapter 3, we conducted drone flights over 14 macro-plots at three different altitudes above ground level (10 m, 15 m, and 20 m) and found that while the 10 m flights provided the best remotely sensed survey results, drones are not a suitable replacement for ground censuses. In Chapter 4, we used Resource Selection Function to define critical habitat for the Wright fishhook cactus. Our modeling suggests that geology, elevation, and slope are significant factors in defining cactus habitat. Based on the results of our research we conclude that soil disturbance by cattle may not have a significant influence on Wright fishhook cactus populations or dynamics, and that accurate range wide population estimates may be best obtained through ground surveys within the predicted critical habitat.
9

Produktive und sichere Netzanwendungen

Wolf, L., Richter, F., Heik, A., Meyer, R., Ehrig, M., Heide, G., Fischer, G., Kalfa,, Junghaenel, J., Parthey, M., Grunewald, D., Huebner,, Sontag, R., Riedel, W., Harder, F., Becher, M., Mueller, T., Ziegler, C., Anders, J., Breiler, A., Friedrich, R., Koehler, S. 13 July 1999 (has links)
Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur Rechnernetze (Fakultaet Informatik) der TU Chemnitz. Globales Thema: Produktive und sichere Netzanwendungen
10

Produktive und sichere Netzanwendungen

Wolf, L., Richter, F., Heik, A., Meyer, R., Ehrig, M., Heide, G., Fischer, G., Kalfa, Junghaenel, J., Parthey, M., Grunewald, D., Sontag, R., Riedel, W., Harder, F., Becher, M., Mueller, T., Ziegler, C., Anders, J., Breiler, A., Friedrich, R., Koehler, S. 13 July 1999 (has links)
Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur Rechnernetze (Fakultaet Informatik) der TU Chemnitz. Globales Thema: Produktive und sichere Netzanwendungen

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