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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.
111

The Early Post-restoration Population Dynamics and Community Interactions of a Former Agricultural Field in the Carolinian Canada Life Zone

Inlow, Katelyn J. January 2010 (has links)
Monitoring ecological restoration at the community scale provides insight into how the population dynamics and community interactions are progressing through time in comparison to a restoration’s goals and reference conditions. This study monitored the early post-restoration dynamics of a sand plain located in the Carolinian Canada ecozone called Lake Erie Farms. The restoration consisted of restoring three habitats via sculptured seeding: a mesic forest, oak woodland, and sand barren. The hypothesis of this study is that the restoration efforts have established population dynamics and community interactions consistent with successional patterns expected from comparative literature. Community ecology, directed succession, and alternative stable states are the underlying theories that provided a conceptual and theoretical lens from which to study the objectives and hypothesis. To gain insight into the community dynamics at Lake Erie Farms the vegetation abundance, seed abundance and viability of the seedbank, seed viability of the 6 most dominant species (3 most dominant native species & 3 most dominant weedy species), and soil moisture & pH were monitored. The analysis was conducted using a RMANOVA of a nested design (P > 0.001, 0.01 and 0.05) to compare the variables in relation to the site (i.e. the sum of all the quadrats), the restoration treatment nested within the site, the field nested within the site, the transect nested within the restoration treatment and the quadrat nested within the restoration treatment. The significant findings of this study include: i) the restoration treatments are producing similar results as those expected from the literature, though there is evidence of the sculptured seeding treatment accelerating the successional stage at Lake Erie Farms compared to abandoned agricultural fields in similar ecosystems because of the presence of later-successional species; ii) the control areas are less diverse than each of the restoration units (P>0.05); and iii) the soil moisture among the treatments is beginning to diverge into the desired restoration units.
112

Implications of Climate Change on the Growth of Two Tropical Agroforestry Tree Seedlings

Esmail, Shahira January 2010 (has links)
Tropical agroforestry systems are perceived to have the capacity to be resilient to future changes in climate. This study quantifies the response of two tropical agroforestry tree seedlings; Gliricidia sepium (Jacq.) Walp and Cedrela odorata L. to increases in atmospheric concentrations of carbon dioxide (CO2) (800 ppm), temperature (+2°C daytime and +3°C nighttime) and the combined conditions. As well, this study analyzes the microbial community structure and nutrient concentration in response to elevated concentrations of CO2 on tropical silvopastoral soil, conventional pastoral soil and a regenerated forest soil. Both tree species demonstrated very individual responses to the different climate scenerios. While no significant CO2 fertilizer effect was observed in either species the combined treatment demonstrated a significant increase in seedling height for both species. The response of G. sepium to the combined treatment was similar to its response to the temperature treatment which could be a result of achieving the optimal range in temperature for growth. As well, an increase in C:N ratio from G. sepium seedling leaves under the combined treatment indicates the possibility of the nutrient concentration diminishing thereby reducing the role of this species as a provider of high nutrient biomass. The soil microbial community showed very little change in response to elevated concentrations of CO2 and differences in community structure between sites were also negligible. Soil nutrient concentration maintained the best balance over the course of both twelve week incubations for the regenerated forest site followed by the silvopastoral site and lastly the conventional pasture site. The response of soil nutrient concentration to elevated concentrations of CO2 was negligible reflecting the response of the soil microbial community.
113

Assessing the Resilience of Ontario’s Low Water Response Plan under a Changed Climate Scenario: An Ontario Case Study

Disch, Jenna January 2010 (has links)
Water is essential to sustaining aquatic environments and is also a resource upon which many human-sectors depend. During times of reduced supply, competition or conflict may arise regarding its distribution due to its importance to local economies and its life giving benefits. The Ontario Low Water Response (OLWR) Plan is designed to deal with how water might be allocated under situations of reduced supply. When forced with data from the Coupled Global Climate Model 1 (CGCM1), the Guelph All Weather Storm Event Runoff (GAWSER) hydrologic model projects scenarios of reduced flows for the Grand River watershed, an area within the Province of Ontario. A level III declaration, which marks the highest stage of water emergency has never before been declared in the Province of Ontario, meaning there is uncertainty regarding how OLWR might operate. Using one scenario of climate change, this study explores the resiliency of the OLWR mechanism to operate under the demands of a changing climate and a growing population through interviews. Results show that the mechanism is not resilient enough to operate under conditions of reduced flow due to ambiguity in the mechanism and the tendency for humans to trump environmental uses of water, leading to detrimental effects on the fishery. Recommendations from this study suggest that ambiguities in the mechanism be revisited and clarified with a shift towards a proactive approach in order for environmental integrity to be upheld under scenarios of reduced flow.
114

Assessing the Resilience of Ontario’s Low Water Response Plan under a Changed Climate Scenario: An Ontario Case Study

Disch, Jenna January 2010 (has links)
Water is essential to sustaining aquatic environments and is also a resource upon which many human-sectors depend. During times of reduced supply, competition or conflict may arise regarding its distribution due to its importance to local economies and its life giving benefits. The Ontario Low Water Response (OLWR) Plan is designed to deal with how water might be allocated under situations of reduced supply. When forced with data from the Coupled Global Climate Model 1 (CGCM1), the Guelph All Weather Storm Event Runoff (GAWSER) hydrologic model projects scenarios of reduced flows for the Grand River watershed, an area within the Province of Ontario. A level III declaration, which marks the highest stage of water emergency has never before been declared in the Province of Ontario, meaning there is uncertainty regarding how OLWR might operate. Using one scenario of climate change, this study explores the resiliency of the OLWR mechanism to operate under the demands of a changing climate and a growing population through interviews. Results show that the mechanism is not resilient enough to operate under conditions of reduced flow due to ambiguity in the mechanism and the tendency for humans to trump environmental uses of water, leading to detrimental effects on the fishery. Recommendations from this study suggest that ambiguities in the mechanism be revisited and clarified with a shift towards a proactive approach in order for environmental integrity to be upheld under scenarios of reduced flow.
115

The Influence of Stakeholder Values on the Acceptance of Water Reallocation Policy in Southern Alberta

Parrack, Cameron 06 December 2010 (has links)
Historically, a great deal of water has been allocated to the agricultural sector in Alberta to support economic development and to contribute to food security. However, demand from other areas has increased in recent years, notably from the environment. Meeting new demands while still satisfying existing users has become a significant challenge. The combination of increased water use efficiency and productivity combined with reallocating water from agriculture to other sectors has emerged globally as a solution to this challenge. Thus, new policies regarding water reallocation need to be developed. Designing policies that are acceptable to the various stakeholders involved poses a considerable challenge. The values held by individuals determine how they will react to new public policies. Hence, to support effective policy making, a better understanding of how the non-irrigator population perceives water reallocation issues is necessary. Using mail-out surveys to collect data from the populations of Lethbridge, Alberta, and the surrounding smaller communities, this research aimed to identify the values regarding water allocation held by domestic, non-irrigator water users, and to determine how these values influence their acceptance of water allocation policies. Findings from the survey reveal how non-irrigators’ values influence their opinion of water transfers from the irrigation sector to the urban and environment sectors, and the conditions under which they should take place. A pro-environment value orientation was most prominent amongst the urban sample, while the rural sample was mainly moderate in their value orientation. The large moderate value cluster within the rural sample represented both pro-economic and pro-environment values depending on the focus of the survey item. Statements that would affect the community (irrigation sector) were met with pro-economic values while statements that involved making a personal sacrifice in order to protect the aquatic environment were strongly supported. Value orientation was found to greatly influence the respondents’ perception of water reallocation policy.
116

The spring reverse migration of landbirds in the Pelee region: 2010-2012

Burrell, Kenneth 20 September 2013 (has links)
The spring reverse migration of landbirds (i.e., birds flying in the direction opposite to be expected), within the Great Lakes region is controversial because it is not understood if the extent or reversal of flight direction in spring is truly a change in migratory patterns or a brief anomaly. It is also not clear what the fitness and community level impacts are. My objective was to determine what and how weather influences reverse migration and to determine which species and families of birds participate the most frequently in this form of flight. I examined species which are participatory (and those that are not) as well as the impacts of specific weather covariates on the abundance of landbirds and focused explicitly on the putative reverse migration of landbirds. Field sites were located at the extreme southern tip of Fish Point, Pelee Island (2010-2012) and Point Pelee National Park (2012), where my field assistant and I visually recorded the total number of birds observed to be reverse migrating, while identifying all birds to species or family as best possible. This study was conducted over 97 days during April 26 – May 20, in 2010-2012. Information pertaining to potential reverse migration has only been formally documented twice in the Great Lakes region, most recently in 1951. I undertook a descriptive analysis to compare the numbers of individuals of bird species and families. Temperate and neotropical migrants were examined, compared, and divided into sub-sets based on their geographic ranges. I identified species at risk and vagrants which I observed during reverse migrations. Based on provincial population estimates, I determined the proportion of all reverse migrants where ≥200 individuals were observed. A descriptive analysis was undertaken to determine differences between sites (i.e., Point Pelee and Fish Point) in the final year of surveys (2012). Species and abundance were comparatively differentiated between each site and subsequently compared. While very few birds were observed flying anything but south, a total of 61,677 birds of 80 species was documented flying south. My results indicate temperate migrants vastly outnumbered neotropical migrants (as much as 4:1) and numbers of birds varied between study sites. Temperate migrants were noted to be more common (in the final study year) at Point Pelee compared to Fish Point, while neotropical migrants were more numerous at Fish Point than Point Pelee. Despite the fact that most migrant species participated in reverse migrations (i.e., of the species regularly occurring in the Pelee region at this time of year), complete absences were noted, most notably in Catharus thrushes, while species such as Rose-breasted Grosbeak and Scarlet Tanager, and families such as Tyrant Flycatchers, Vireos and Sparrows were observed to be less prevalent than anticipated. Species at risk and vagrants were noted relatively frequently during this study, suggesting that these surveys are an efficient and potentially important tool for migration monitoring in this region. Diurnal migrants, most notably Blackbirds, were observed to engage in reverse migration in higher numbers than nocturnal migrants, such as Wood Warblers. Seven weather covariates were measured and modeled with the total number of birds detected using R to determine which covariates explain the most amount of variation of the total number of birds during my surveys. I used an AICc approach to select the best model for each hypothesis. After selecting the top weather covariates with time lags according to the best (lowest) AICc values, I built general models by comparing all possible combinations of the covariates identified in the top models for each hypothesis. I included a random effect intercept for study site to discern any site difference or similarities between Point Pelee and Fish Point and specified a Poisson distribution (log-link function as implemented in the LMER package) because the data set was continuous (time-series) and count oriented. My adjusted time lag results show that most migrants tend to migrate during and ahead of inclement weather and/or periods of south winds. I also found that all identified covariates influence reverse migration to some degree. Wind direction and barometric pressure were the most significant of the covariates examined (β = 0.718 and -0.213, respectively). Specifically, wind direction is the most important covariate in explaining reverse migration, with days of south winds dramatically increasing the probability of higher numbers of birds during surveys. Low barometric pressure is also important for explaining the number of observed reverse migrants; therefore, days with lower barometric pressure have a greater likelihood of increased bird observations. Based on my observations and results I theorized that while reverse migration pertains to a distinct form of flight, it is likely not an actual form of migration. This form of flight at its simplest is likely a form of reorientation, whereby migratory birds take advantage of local weather conditions by flying south for extended distances. I anticipate that this form of flight must have serious consequences for the fitness levels and life-cycles of migratory birds. Studies looking at reverse migration provide a useful tool for migration monitoring, particularly as it is an underexplored phenomenon. Observations of thousands of birds, many of which are either species at risk or vagrants, collected in an efficient manner are vital for determining population trends related to migratory birds. Continuing this study would aid on-going monitoring programs assessing bird populations passing through the lower Great Lakes region. These studies will also help us understand the impacts of climate and climate change on migratory birds.
117

Mapping Youth-led Engagement: Impacts of Youth-led Engagement in English Canada over the Last 35 Years

Ho, Elaine January 2013 (has links)
This study explores how youth have inspired social change in Canada from 1978 to 2012. The objectives of the research include defining youth-led engagement in Canada, understanding its role as a change agent, and mapping the relationships between strategies and impacts. The goals of this study are to help current and future youth maximize opportunities that are likely to result in the greatest success, as well as increase opportunities for youth to be involved in decision making processes by validating their contributions. The research includes youth who effect change in a variety of contexts from across Canada. Data collection consists of an online media search and supplementary document reviews. A media content analysis methodology is applied to extract the data, while frequencies and cross tabulations in the form of chi-square tests were used to analyze them. The results show a strong relationship between strategies youth use and the impacts that follow. Further, the data show that youth have made some of their most frequent contributions by participating in political processes to address issues of equality, empowerment and social justice. Patterns between youth efforts and long-term changes in society are discussed, and the measurement of impacts is considered. This research measures three types of impacts youth have had on social change: individual, community/interorganizational, and systemic. It highlights the importance of institutionalizing the inclusion of youth as part of decision making processes in Canada, and validates the argument that youth have important contributions to make to our diverse society.
118

Citizen Engagement and the Governance of Sustainable Communities

Jawhary, Diala 08 December 2010 (has links)
This study develops an interdisciplinary exploratory approach for understanding concepts and tools for local participation that leads towards sustainability. The research goals include : identifying effective public participation criteria and sustainability criteria, identifying lessons that might be learned from Canadian communities that have used, and applied, public participation and sustainability initiatives, exploring how might these lessons be applied to a mid-sized community such as the City of Waterloo, and exploring how might citizen advisory committees be more effectively engaged to foster sustainability. The ultimate objective is to identify effective participation processes in order to foster sustainability using both secondary literature and a case study methodology. Findings were assessed in the analysis of lessons learned of communities located across Canada to be later refined and tested using the case study of the City of Waterloo, Ontario. The thesis contains an analysis of the conceptual literature and case study research to ascertain the factors that determine effective public participation processes towards sustainability and recommendations for citizen advisory groups that can be used by various local governance stakeholders in a Canadian context.
119

Raptor Mortality and Behavior at Wind Turbines Along the North Shore of Lake Erie During Autumn Migration 2006-2007

Dance , Kevin January 2011 (has links)
During 2006 and 2007 behavioral observations surveys of raptors were conducted at 12 turbines of a 66-turbine wind farm near Port Burwell, Ontario, Canada. Mortality surveys were conducted at all turbines in the wind farm with additional search effort at the twelve turbines where behavioral monitoring was conducted. The wind farm is located along a significant autumn raptor migration corridor along Lake Erie which is in the area of the Central Flyway. Only one raptor fatality was found each year at the 12 turbines used in the study, with one additional fatality found at the other 54 turbines in the wind facility. The estimated mortality rate for Erie Shore Wind Farm ranged from 0.028 to 0.049 raptor fatalities/MW/autumn. The estimated mortality rate for Erie Shores is at the low end of mortality for North American wind facilities outside of California, and which are not located in known migratory pathways. My findings suggest that the presence of high numbers of migrant raptors passing over a wind facility site does not automatically equate to high collision mortality. Over 5,579 observations of individual raptor passes within 250m of a turbine were recorded. The majority of raptors (73%) passed outside of blade sweep height. The majority of raptors avoided entering the risk zone of operational turbines with 2.92% (n = 159) of raptors observed passing within the risk zone of blade sweep height above ground and 0-40m out from the turbine base. The majority (73%) of raptors that entered the risk zone did so under conditions when risk was reduced due to turbine blade orientation in relation to the raptors’ direction of movement or when the turbine was not operational.
120

Rural Community Vulnerability to Food Security Impacts of Climate Change in Afghanistan: Evidence from Balkh, Herat, and Nangarhar Provinces

Mihran, Rozbih January 2011 (has links)
Climate change is taking its toll on Afghanistan. Warming temperatures and decreasing precipitation levels over the last fifty years have led to innumerable weather anomalies causing droughts, floods, unseasonal precipitation, falling ground water tables, desertification, and loss of biodiversity. While it is projected that further change in climatic conditions will take place over the coming decades, the impacts of these environmental stresses on the living conditions and livelihoods of Afghans have already been significant and adverse. Among all population groups, rural communities in Afghanistan are particularly vulnerable to the effects of climate change due to their strong dependence on agriculture for living. This exploratory research used a qualitative methodology to investigate and document firsthand the vulnerability of the rural communities to climate change impacts in the context of food security in Afghanistan. To this end, three villages in Balkh, Herat, and Nangarhar provinces were studied for their exposure to climate change and the communities’ adaptive capacity to cope with and avert the climate-related stresses. Additional key informant interviews were conducted to learn about similar issues in other rural regions of the country. The study found that climate change has substantially contributed to increased food insecurity in the rural communities throughout Afghanistan over the last two decades and that the rural households are facing real challenges to generate income from agricultural activities while taking desperate measures to cope with and adapt to climatic conditions.

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