Herbicide sod suppression during pasture renovation by legume sod-seeding often results in the loss of potentially usable forage, weed encroachment, and inadequate glass-legume ratios. A study was conducted to investigate the viability of sod suppression by sheep grazing or mowing, as alternatives to herbicide, during pasture renovation with no-till seeding of red clover (Trifolium pratense L.) or white clover (Trifolium pratense L.). Sod suppression methods evaluated were: strategically timed mowing or sheep grazing to 5 or 10 cm at seeding and during legume establishment, or similarly managed mowing or sheep grazing with an additional defoliation to 5 cm the previous fall. Additional treatments included suppression by herbicide and, unsuppressed and unseeded controls. Treatments were evaluated by determining clover plant population, botanical composition, forage yield and quality. Physical (mowing or grazing) and herbicide sod suppression resulted in similar clover plant populations; clover yields tended to be higher with herbicide suppression. However, increasing the intensity of physical suppression increased clover yields. Forage quality was increased only with sod suppression by grazing or herbicide when compared with the unimproved control. Although, for grazing this was attributed to a more frequent defoliation regime and not to the renovation itself. Unlike suppression with herbicide, physical suppression did not decrease total seasonal forage yields in the renovation year when compared with controls.

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A historic turnover in the teaching profession has begun. There is no doubt that worldwide demand for teachers is on the rise and will continue to increase over the next decade. Yet many new teachers leave the profession, stating reasons such as low salaries, lack of professional opportunities and career advancement, and heavy workloads. The present study examined the concerns (in-school, external and personal) of elementary and secondary school teachers. The purpose of this research was to determine if teachers in Quebec, Canada, have concerns similar to teachers in other countries where studies are more common. This study also examined if there were any differences related to teachers' stages of teaching, level of education, and gender. Four hundred and fifty-seven teachers (335 females and 120 males) from five school boards in Quebec participated in this study. The five school boards represented urban, suburban, rural, large and small English-language boards. The instrument designed for this study was a questionnaire based on the teacher concerns identified in the literature. The questionnaire, named the Public School Teacher Concerns Questionnaire, has seven sub-scales and 64 items. Quantitative and qualitative analysis of respondent thinking reveal similar concerns regarding eight factors (37 items) derived by factor analysis: student characteristics and behaviour, teacher/administration relationship, student behaviour (non-academic), material and temporal resources, teachers control of day-to-day activities, professional development and opportunities, status of profession, and degree of non-teaching duties. Implications of the findings and directions for future research are offered.

Building a home is a process, not an event. It is a continuous and dynamic relationship between dwellers and their dwellings. Using houses as cultural artifacts, this thesis examines the morphogenesis of a French-Canadian neighbourhood in Montreal. / Cite-Jardin du Tricentenaire was a wartime effort of a small group of entrepreneurs who had dreams of building an "ideal", French-Canadian community. Its high rate of persistence over the past fifty years--one in five households are original settlers--makes it a convenient laboratory for the study of community development. / The research revolves around several themes: the planning behind the original housing; the physical evolution of the houses themselves; the experiences and perceptions of the homeowners; and the cultural and temporal context into which the housing was placed. This research establishes relationships between transformation behaviour and household characteristics, by analyzing how households adapt their housing situation to accommodate changing needs and aspirations.

The use of agricultural chemicals, such as nitrogen fertilizers in corn production, often results in water pollution. This research, comprising three parts, was designed to investigate the effects of nitrogen fertilizer application rates, water table management, and corn cropping systems on drainage water quality. The first part was a field study, to investigate the impact of two cropping systems and water table management on nitrate loss through tile drainage. The considered water table treatments were free drainage, and subirrigation with target water table depths at 0.5 m or 0.75 M below the soil surface. Corn (Zea mays L.) monoculture and corn intercropped with annual ryegrass (Lolium multiflorum Lam.) were investigated. The highest annual tile drainage losses of 21.9 kg N/ha were measured in monocropped, freely draining plots. Subirrigation with a water table depth of 0.5 m reduced tile drainage loss of N by over 70%, and intercropping corn with ryegrass under free drainage reduced leaching losses by 50%. / The second part of the research was a simulation study with the water quality model, DRAINMOD-N. The water quality impact of fertilizer application rate under free drainage, subirrigation and controlled drainage was evaluated. Leaching losses, denitrification and N accumulation in the soil profile were investigated. Using data obtained from the field experiment, the performance of DRAINMOD-N was evaluated. DRAINMOD-N assumes that denitrification follows first order kinetics, contrary to field measurements which showed little correlation between denitrification rate and NO$ sb3 sp-$-N concentration. Therefore, DRAINMOD-N was modified by replacing the original denitrification function with the Michaelis-Menten relationship. In so doing, denitrification is expressed as a first order process when NO$ sb3 sp-$-N concentration limits denitrification, and as a zero order process for non-limiting NO$ sb3 sp-$-N concentration. / For denitrification to be a decision making criterion of water table management, inexpensive but reliable measurement techniques are required. Thus, the purpose of the final part of this research was to formulate a technique for measuring real-time denitrification rate. Denitrification rate could be expressed as a function of soil redox potential (Eh) and temperature. Laboratory and field studies showed that factors such as soil nitrate and organic carbon had negligible effect on denitrification rate. Therefore, it can be concluded that for most agricultural soil, Eh and soil temperature will satisfactorily describe denitrification variation.

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