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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.
141

Factors Considered in Determining Educational Setting for Students with Emotional Disturbance

Hoge, Matthew Ryan January 2013 (has links)
The present study identified factors influencing determination of educational setting for students with Emotional Disturbance (ED). Determination of most appropriate educational setting, a key provision of students' individualized education programs (IEP) continues to be one the most contentious issues in special education. Focus group interviews were conducted to identify and understand factors contributing to placement decisions for IEP teams. Qualitative analysis of interviews produced three themes. First, IEP team members' beliefs, knowledge, and attitudes of ED influenced their recommendations for placement decisions. Second, teacher and resource-based factors played as critical a role as student-based factors in where students were placed. Third, needs of school-based stakeholders (i.e. teachers, principals, district officials) competed with those of the student with ED. Previous interview-based research on factors related to the determination of educational setting for students with ED relied predominantly on a single population: teachers. This study extends the research literature by including psychologists and principals as participants. The findings, provided by a cross section of school districts and personnel, highlight challenges related to the provision of high quality educational services for students with ED.
142

The ethics and values underlying the "emulation of natural disturbance" forest management approach in Canada : an interdisciplinary and interpretive study

Klenk, Nicole 11 1900 (has links)
This thesis aims at bringing about a greater awareness of the interpretive nature of forestry sciences by examining the ethics and values underlying the “Emulation of Natural Disturbance” (END) forest management approach in Canada. The thesis contains four main manuscripts. The first manuscript reports on a mental models analysis of the meaning of the END for academic forestry scientists across Canada. The results of this study indicate inconsistencies and contradictions between scientists’ mental model of the END, which puts into question the utility and appropriateness of the END for forestry policy. The second manuscript discusses the ethics underlying the END and critiques its policy implications from a pragmatic perspective. In the third manuscript the ethics and values underlying the END are put in relation with Holmes Rolston III’s ethics of “Following Nature”. The last manuscript reports on a survey of forestry curricula across North America conducted to ascertain the level of formal training in ethics afforded to professional foresters and natural resource managers. This manuscript contains a proposed course syllabus in forestry ethics. The curricula study complements the other manuscripts in that it is meant as another means by which to promote interdisciplinary dialogue among forestry scientists, environmental ethicists, and social scientists. In this thesis, in addition to trying to illustrate how ethics shape our interpretations of forests, a pragmatic approach is used to dissolve the fact/values and Nature/Culture dichotomies in forestry sciences and to argue for a more democratic approach to forestry policy.
143

Forest Management Does Not Emulate Natural Disturbance with Respect to Plant Diversity and Forest Community Composition

Webster, Neil 17 January 2013 (has links)
Forest management practices in Ontario are required to emulate natural disturbance in an effort mitigate the anthropological impact on the environment. This is enforced by the Crown Forest Sustainability Act, initiated in 1994, yet inadequate research has been done to support management techniques that satisfy the legislation in regards to the plant diversity and community composition. A series of 435 plots on 139 sites were established in Northern Ontario, consisting of stands of various ages and disturbance origins. Plant diversity and community composition were estimated with a variety of diversity indices and multivariate community analyses. My results show that managed stands are more diverse than those with a natural disturbance origin based on multiple diversity indices. Detrended Canonical Correspondence Analyses revealed considerable variation in community composition among all stands. Plant communities differ between the stands of different disturbance origins (managed/unmanaged), and these differences are influenced by stand age. These results reject the hypothesis that current forest management practices emulate natural disturbance. / Forest Ecosystem Science Coop Inc NSERC CRD Program NSERC Strategic Grant Progam Ontario Ministry of Natural Resources Canadian Forest Service
144

Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island, Russia

Gailey, Glenn Andrew 03 October 2013 (has links)
The western North Pacific population of gray whales (Eschrichtius robustus) is critically endangered of extinction. The population size is estimated to be 131 individuals with 31 reproductive females. Throughout their potential home range, the western gray whale population face several threats to their future survival. On their only known feeding grounds off the northeastern coast of Sakhalin Island, Russia, anthropogenic activity has increased in the past decade due to oil and gas exploration and platform/pipeline construction. This dissertation examines the influences of geophysical seismic surveys (pulse sounds) and platform/pipeline installation (continuous sounds). Each chapter progressively improves upon behavioral models that assess changes in gray whale movements and respirations relative to anthropogenic activity. Theodolite tracking and focal follow methodologies were employed to collect gray whales' movement and respiration information during and in the absence of anthropogenic activity. Spatial, temporal, environmental, and acoustic (pulse and/or continuous) sound levels and non-sound related anthropogenic variables were included as explanatory variables to examine their influence on movement and respiration response variables, such as speed, orientations, dive/surface time, breathing rates, etc. During the 3-D seismic activity, gray whales traveled faster, changed directions of movement less, were recorded farther from shore and stayed underwater longer between respirations as the received sound level exposure increased. During platform/pipeline installations, western gray whales increased their distance from shore with indicators of stress (rapid breathing) and observed to be sensitive to close distance of approach by vessels. No acoustic influence on western gray whale behavior was found during a 4-D seismic survey; however, sample sizes were small in this study to sufficiently detect more subtle to moderate changes in gray whale behavior. These studies illustrate short-term influences anthropogenic activity had on western gray whale behavior which could lead to longer-term responses that may be detrimental to the survival of certain individuals and/or the population. A comprehensive analyses are proposed to increase sample sizes to identify subtle to moderate behavioral changes as well as examine alternative hypotheses to the null hypothesis of no impact used in this dissertation. With the potential to displace individuals/population out of critical feeding habitats needed for their annual survival and the expected increase of anthropogenic activity in the future, this dissertation highlights the importance to monitor and identify problems and suggest alternatives to development/activities that may be impacting this endangered population of gray whales.
145

Conservation and ecology of bryophytes in partially harvested boreal mixed-wood forests of west-central Canada

Caners, Richard T. Unknown Date
No description available.
146

Disentangling the effects of disturbance and habitat size on stream community structure

Jellyman, Phillip Graeme January 2011 (has links)
Our ability to predict community responses to environmental stress remains limited. To address this issue, I investigated how species abundance, community composition and food-web structure varied across abiotic gradients (principally disturbance and habitat size) in New Zealand streams. In surveys, community composition, biomass and richness were all strongly influenced by flood-related habitat disturbance, although disturbance influenced each trophic level via different mechanisms. Experiments indicated that macroinvertebrate prey communities were primarily structured by physical disturbance effects, whereas predatory fish communities were structured by physical disturbance effects and disturbance-mediated changes to prey communities. Prey community biomass and composition affected fish species identity and abundance and an in situ stream channel experiment suggested that prey communities were structured by trade-offs between resisting biotic interactions in physically stable environments and successfully exploiting highly disturbed habitats. The prey community traits associated with different disturbance regimes then directly influenced the composition and predatory impact of the resultant fish communities. In addition to disturbance-mediated biotic interactions, abiotic gradients also provided strong selection pressures on predatory fish communities. In particular, disturbance and habitat size strongly influenced predator community responses (e.g., biomass and maximum body size) in surveys and experiments. However, a habitat’s capacity to support predator community biomass was largely determined by its size. Food-web structure changed with habitat size; small streams supported more prey than predator biomass, whereas large streams had inverted biomass pyramids (i.e., more predator than prey biomass). Similar relationships between food-web structure and habitat size were found in grassland and forested streams, but terrestrial invertebrate subsidies meant that forested streams supported more predator biomass per unit area than grassland stream food webs. My results indicate that human actions resulting in habitat loss (e.g., water abstraction or river impoundment) and increases in flood-related disturbance events (e.g., climate change) are likely to have significant impacts on stream food webs, ultimately leading to habitats that support smaller fish communities (i.e., less biomass, smaller body size). This means that ecologists and managers will need to consider the separate, interactive and indirect effects of disturbance and habitat size on ecological communities if we are to accurately predict and manage food-web responses to global environmental change.
147

Design of Fault Tolerant Control System for Electric Vehicles with Steer-By-Wire and In-Wheel Motors

Hayakawa, Yoshikazu, Ito, Akira 09 1900 (has links)
7th IFAC Symposium on Advances in Automotive Control, The International Federation of Automatic Control, September 4-7, 2013. Tokyo, Japan
148

Effects and consequences of agriculture, tourism and hunting on the birdlife at Gialova lagoon : An area of international importance for migratory birds

Söderblom-Tay, David January 2014 (has links)
Many populations of migrating waterbirds in Africa and Western Eurasia are in a long-term decline, largely because of the loss of wetlands along their migration routes. Between 1950 and 1985, 63 % of the wetlands in Greece were lost due to human activities. However, humans are also a source of more direct disturbance to birds that may have a negative influence on their fitness. The purpose of this study has been to assess how human disturbance in the form of agriculture, tourism and hunting might affect the birdlife in a coastal lagoon in southwestern Greece, and, if needed, propose measures on how to improve the status of the birdlife. To evaluate this, interviews and studies of monitoring reports and literature have been conducted. The studied area, Gialova lagoon, is the southernmost wetland in the Balkan Peninsula, which makes it especially important for migratory birds. The study shows that the major threats to the lagoon have already been dealt with. However, there are still improvements that can be made. Currently, agriculture seems to have the most negative effect on the concerned area, but since there appears to be an ambition to increase tourism in the area this may change in the future. Disturbance from hunting only plays a minor role in the area around the lagoon. The establishment of an official management body as well as an official management plan would probably be an effective way to continue the conservation work and reduce the disturbance of human activities in Gialova lagoon.
149

Ecological impacts of Highveld gerbils (Tatera Brantsii) on a rehabilitated ash disposal site / Nevil Ian Wright

Wright, Nevil Ian January 2006 (has links)
Tatera brantsii was numerically dominant in the small mammal community on the plateaux of the rehabilitated ash disposal sites of ESKOM's Hendrina Power Station in 1998 and 1999 (Vermaak 2000). The species seemed well adapted to exploit this environment and, through biopedturbation, had altered the topsoil structure and chemistry. The consequences of this and other activities also affected the rehabilitated plant community of the PFA-dam habitat. Burrowing appeared limited to just under the topsoil layer, and seemed more extensive than burrows of this species in natural ecosystems. The burrow system architecture was mapped and quantified, and localised increases in nitrates, phosphorous and organic carbon in immediately associated substrate were noted. However, this substrate enrichment was transient, and disappeared following the abandonment, and subsequent collapse of burrow systems, when gerbil colonies migrated away from the area. The mixing of soil horizons also resulted in a more homogeneous substrate, which was more friable, and thus drier. The high pH and salinity of the topsoil layer in areas undisturbed by gerbil burrowing, and concentrations of particular elements associated with either the topsoil covering or the ash, were reduced as a consequence of substrate mixing in disturbed areas. Gerbil impacts on the substrate of this habitat seemed to promote pedogenesis, eliminating the sharp distinction between the topsoil covering and the ash below, but the re-exposed ash of the burrow mounds would become subject to erosion, and reduce the effectiveness of the rehabilitation effort. Gerbil activities increased the number of plant species, especially ruderal forbs, comprising the plant community of the PFA-dam habitat, but plant community diversity was not significantly increased. However, numerical dominance by few tussock grass species was diminished , possibly reflecting burial under mounds of excavated substrate. The biomass and cover of some grass species were reduced in areas of gerbil impacts, and plant lifecycles appeared to be completed sooner in areas affected by gerbil activities. These effects may be as a result of the drier substrate produced following the collapse of the extensive network of abandoned burrows. The succession of this plant community towards an underutilised grassland state, the expected outcome of the rehabilitation effort, was minimally affected by gerbil activities. The effects of T.brantsii activities in this PFA-dam habitat were not as distinct as the effects noted by other authors studying fossorial rodent impacts in less disturbed habitats. This could be because further disturbances in this habitat would merely add to the currently disturbed state, whereas disturbance in more natural habitats, would show more of a change from the initial state. / Thesis (M.Sc. (Zoology))--North-West University, Potchefstroom Campus, 2007.
150

Quantifying grizzly bear habitat selection in a human disturbed landscape

Stewart, Benjamin Peter 31 August 2011 (has links)
Understanding the use of habitat by large carnivores in the presence of ever increasing anthropogenic disturbance is crucial to managing threatened species. In the foothills of the Rocky Mountains in west-central Alberta, Canada the grizzly bear (Ursus arctos) faces such disturbance, and is especially susceptible due to their low fecundity and large home ranges. Grizzly bear mortality increases with proximity to human disturbance, leading to the conclusion that anthropogenic forest disturbance is incompatible with successful grizzly bear habitat The purpose of this research is to evaluate grizzly bear habitat use as it relates to forest disturbance. The general approach was to quantify grizzly bear habitat use and compare to an expectation of use calculated through conditional randomization. The research involved two distinct analyses. First, grizzly bear use of natural edges (transitions between land cover classes) and anthropogenic landscape edges (roads, pipelines, and forest harvests) was quantified and compared between seasons and sex. Females were found to use anthropogenic edges more than natural edges, whereas males used natural edges more. Despite the increased mortality threat arising from increased human access around anthropogenic disturbances, female grizzly bears are using anthropogenic edges more than natural edges, meaning anthropogenic edges may not be incompatible with successful grizzly bear populations. Knowing that female grizzly bears use anthropogenic edges more allows managers to limit access to areas with specific edges desirable to female bears. While creating more disturbances is not the solution to managing for better grizzly bear habitat, limiting human access to areas of beneficial edge could decrease mortality risk. Knowing that grizzly bears use edges, the second analysis quantified use of forest disturbances of varying ages, and determined what disturbance characteristics drive grizzly bear selection of forest disturbances. A 40-year forest disturbance dataset was generated through image differencing of the tasselled cap angle transformation of Landsat imagery (MSS, TM, ETM+). Disturbances were grouped into decades, and compared. Disturbances were labelled as selected or not selected through a randomization process, and selected disturbances were compared to not-selected disturbances using four landscape metrics: disturbance size, disturbance elevation, average tasselled cap transformation greenness, and distance from disturbance to nearest human settlement along a road network. Results indicate that bears select for larger disturbances in all seasons. Females select for disturbances with low remotely-sensed greenness in all seasons, where males select for disturbances with low remotely-sensed greenness in the spring and fall, but high remotely-sensed greenness in the summer. Females select for disturbances at a consistent elevation, whereas males show seasonal variation. Both sexes avoid the most recent disturbances from the 2000s. Females show greater selection of disturbances in the summer and fall, whereas males select disturbances in the fall the least. Knowing that bears select for large disturbances, and females select disturbances at a consistent elevation, forest managers can limit human access to these areas in order to limit human and bear interactions and reduce mortality risk. / Graduate

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