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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.
231

Structural and behavioural adaptations in the large water skater Gerris najas (Degeer) with particular reference to water surface phenomena

Eastwood, Edward Anthony January 1992 (has links)
No description available.
232

Effects of the sea lice chemotherapeutant cypermethrin on marine zooplankton

Medina, Matías January 2002 (has links)
No description available.
233

'Small system' modelling of the polluted planetary boundary layer

MacKenzie, Angus Robert January 1989 (has links)
No description available.
234

Knowledge management and environmental management

Miles, Leon Anthony January 2000 (has links)
No description available.
235

The affordances of adolescents' environments

Clark, Charlotte E. S. January 2001 (has links)
No description available.
236

Ina makoce daca yusbemakina: identifying environmental impacts and changes within Alberta's Isga nation

Potts-Sanderson, Misty Faith 07 September 2010 (has links)
This qualitative research was conducted within Alberta’s Isga Nation, specifically Alexis Nakota Sioux Nation and Paul First Nation in central Alberta, Canada. The Isga are located in a hub of industrial activity such as oil drilling and development, sour gas drilling, coal mining, agriculture, and forestry. Despite the whirlwind of industrial activity surrounding them, the Isga people continue to carry out their traditional harvesting activities in and around Alberta, Canadas’ foothills and Rocky Mountains. The research objective was to better understand environmental impacts and changes in Alberta’s Isga Nation. More specifically, document concerns traditional land use harvesters have about: i) the decline in the health and abundance of medicines and berries; ii) the state of health the waterfowl and other wildlife are in; iii) testimony that industrial activity is causing environmental degradation; iv) the health of our lakes and rivers; and v) and worries about how the continuation of the Isga way of life will be affected in the future. The methods, or Isga ways of knowing provide first hand knowledge that the Isga are forced to seek areas outside their traditional harvesting territory to seek medicines and berries; that the wildlife, particularly moose, are showing abnormalities when they are harvested; that the health of the rivers and lakes is rapidly decreasing; and that the survival of the Isga way of life is being threatened today. Moreover, Isga voices will illuminate that their traditional territory is rapidly decreasing in environmental health and abundance because of oil drilling and development, sour gas drilling, coal mining, agriculture, and forestry.
237

The effect of legislation concerning environmental tobacco smoke (ETS) on the short-term health of hospitality workers: A Canada – Italy comparison

Barth, Delaine 26 April 2007 (has links)
Background: Environmental tobacco smoke (ETS) is a combination of the smoke exhaled by smokers and the smoke burning from a cigarette, cigar or pipe that is not being inhaled. It contains over 4000 chemicals many of them being known carcinogens and toxins. The recently-identified hazards of ETS have resulted in the implementation of new legislation to protect non-smokers’ health in jurisdictions worldwide. Purpose: This study tests the hypothesis that legislation eliminating ETS from all enclosed public places improves the health of hospitality workers. Methods: This is a descriptive, case-series study, which investigates tobacco smoke exposure in non-smoking hospitality workers in Canada and Italy. Data was obtained by testing workers for levels of carbon monoxide before and immediately after working in venues where smoking was permitted and was not permitted. Workers also provided information on respiratory and sensory irritation symptoms. Conclusion: Legislation eliminating ETS improves the health of hospitality industry workers.
238

Analyzing the Twin Effects of Trade and Population Ageing on the Environment

Abbes, Chahreddine 29 March 2011 (has links)
Chapter One: When is Free Trade Good for the Environment? This paper provides the conditions under which free trade reduces the emission of pollution. In this paper, we construct a computable general equilibrium model of free trade and environment. Using data from different countries with different characteristics with respect to the stringency of their environmental and trade policies and factor endowments, we simulate a reduction on import tariffs and measure the impact on the volume of emission. Our main findings show that, for a combination of relatively high capital to labour ratio and low level of protectionism, if a country exports the polluting good then, trade liberalization increases the level of emission. Whereas if the country exports the clean good, then the effect of an import tariff reduction on the emission level is positively related to the variation in the producer’s price of the polluting good. Furthermore, we find that under a relatively low level of capital endowment for a country that exports the polluting good, the impact of free trade on the environment depends on the degree of protectionism. // Chapter Two: Ageing and the Environment in an Overlapping Generations Model. We empirically investigate the impact of population ageing on the environment using an overlapping generations model. We decompose the impact into scale, composition, and cohort effects. Using data from the Canadian economy, we simulate the impact of demographic shock on the volume of emission. Population ageing results mostly from a baby bust that follows a baby boom. The demographic transition is characterized by an increase then a decline in the population growth rate. Under the first part of the transition, we find that the scale effect generates more pollution. However, if young generations are more concerned about the environment, an increase in the population growth rate may improve the environment via the composition effects. On the other hand, a decline in the population growth rate (population ageing) creates the opposite results. We further find that cohort effect is positively related to the environment when there is a higher degree of awareness towards a cleaner environment. By comparing scale to both composition and cohort effects, we find that scale dominates both effects, so population ageing causes the level of pollution to fall. // Chapter Three: Does Population Ageing in the North Leads to More Pollution in the South? We construct a two-country model: a rich country (the North) with relatively high level of capital endowment and stringent environmental policy and a poor country (the South) with less stringent environmental policy. Both countries produce a clean and a polluting good and both have access to an exogenous abatement technology. The paper has three main foci. First, it provides an empirical test for the pollution haven and the factor endowment hypotheses. Second, it introduces the issue of population ageing in the North into the question of trade liberalisation and the environment. Finally, it investigates the impact of demographic and trade shocks on the level of emissions in both countries. Results from simulations suggest that an increase in the population growth rate increases the volume of emission in the long run. However, population-ageing generates an opposite effect. In the short term, the scale dominates the composition effect. Empirical evidences show that the level of emission is positively related to the size of population. With respect to trade, pollution increases in the North and falls in the South. Also, we find that demographic changes dominate trade liberalization. Finally, worldwide free trade is bad for the environment, but its effect is marginal.
239

Remote sensing of a dynamic sub-arctic peatland reservoir using optical and synthetic aperture radar data

Larter, Jarod Lee 09 April 2010 (has links)
Stephens Lake, Manitoba is an example of a peatland reservoir that has undergone physical changes related to mineral erosion and peatland disintegration processes since its initial impoundment. In this thesis I focused on the processes of peatland upheaval, transport, and disintegration as the primary drivers of dynamic change within the reservoir. The changes related to these processes are most frequent after initial reservoir impoundment and decline over time. They continue to occur over 35 years after initial flooding. I developed a remote sensing approach that employs both optical and microwave sensors for discriminating land (i.e. floating peatlands, forested land, and barren land) from open water within the reservoir. High spatial resolution visible and near-infrared (VNIR) optical data obtained from the QuickBird satellite, and synthetic aperture radar (SAR) microwave data obtained from the RADARSAT-1 satellite were implemented. The approach was facilitated with a Geographic Information System (GIS) based validation map for the extraction of optical and SAR pixel data. Each sensor’s extracted data set was first analyzed separately using univariate and multivariate statistical methods to determine the discriminant ability of each sensor. The initial analyses were followed by an integrated sensor approach; the development of an image classification model; and a change detection analysis. Results showed excellent (> 95%) classification accuracy using QuickBird satellite image data. Discrimination and classification of studied land cover classes using SAR image texture data resulted in lower overall classification accuracies (~ 60%). SAR data classification accuracy improved to > 90% when classifying only land and water, demonstrating SAR’s utility as a land and water mapping tool. An integrated sensor data approach showed no considerable improvement over the use of optical satellite image data alone. An image classification model was developed that could be used to map both detailed land cover classes and the land and water interface within the reservoir. Change detection analysis over a seven year period indicated that physical changes related to mineral erosion, peatland upheaval, transport, and disintegration, and operational water level variation continue to take place in the reservoir some 35 years after initial flooding. This thesis demonstrates the ability of optical and SAR satellite image remote sensing data sets to be used in an operational context for the routine discrimination of the land and water boundaries within a dynamic peatland reservoir. Future monitoring programs would benefit most from a complementary image acquisition program in which SAR images, known for their acquisition reliability under cloud cover, are acquired along with optical images given their ability to discriminate land cover classes in greater detail.
240

Ina makoce daca yusbemakina: identifying environmental impacts and changes within Alberta's Isga nation

Potts-Sanderson, Misty Faith 07 September 2010 (has links)
This qualitative research was conducted within Alberta’s Isga Nation, specifically Alexis Nakota Sioux Nation and Paul First Nation in central Alberta, Canada. The Isga are located in a hub of industrial activity such as oil drilling and development, sour gas drilling, coal mining, agriculture, and forestry. Despite the whirlwind of industrial activity surrounding them, the Isga people continue to carry out their traditional harvesting activities in and around Alberta, Canadas’ foothills and Rocky Mountains. The research objective was to better understand environmental impacts and changes in Alberta’s Isga Nation. More specifically, document concerns traditional land use harvesters have about: i) the decline in the health and abundance of medicines and berries; ii) the state of health the waterfowl and other wildlife are in; iii) testimony that industrial activity is causing environmental degradation; iv) the health of our lakes and rivers; and v) and worries about how the continuation of the Isga way of life will be affected in the future. The methods, or Isga ways of knowing provide first hand knowledge that the Isga are forced to seek areas outside their traditional harvesting territory to seek medicines and berries; that the wildlife, particularly moose, are showing abnormalities when they are harvested; that the health of the rivers and lakes is rapidly decreasing; and that the survival of the Isga way of life is being threatened today. Moreover, Isga voices will illuminate that their traditional territory is rapidly decreasing in environmental health and abundance because of oil drilling and development, sour gas drilling, coal mining, agriculture, and forestry.

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