6 resultados para 10-Southern Crete

em Brock University, Canada


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This study has three purposes: to establish a chronologically controlled vegetational history for a number of sites in south Southwestern Ontario; to utilize the resulting data to support and/or add to the current understanding of Quaternary geology and stratigraphy, and the glacial and postglacial history of the Great Lakes in south Southwestern Ontario; and to attempt to propose a possible explanation for the extinction of the mastodon in Southern Ontario. Palynological and geochronological analyses were conducted on material collected from eleven sites (east to west): Verbeke Mastodon Site, Woloshko Mastodon Site, Walker Pond II, Pond Mills I, Lake Hunger Bog, Bouckaert Site. Mabee Site, Cornell Bog. Colles Lake I, Folden Mastodon Site and Forest Pond. Individual geochronologically controlled (where possible) vegetational histories were reconstructed for each of the sites investigated. The results of the individual studies, when considered in overview. indicated the existance of an established closed boreal forest throughout south Southwestern Ontario by 10,000 years B.P. This evidence for a significant climatic change coincident throughout south Southwestern Ontario supports the proposed age of 10,000 years B.P. for the Pleistocene/Holocene Boundary (Terasmae, 1972). Remnant patches of 'open spruce parkland' persisted in small local 'wet' areas. It was in these areas that the mastodon was restricted during early Holocene time. With continued encroachment by the surrounding boreal forest, possibly speeded up by this browser's destructive feeding habits, the spruce enclaves shrank and the mastodon became extinct in south Southwestern Ontario. The results of this thesis basically support Dreimanis' (1967, 1968) proposed 'Environmental-Climatic' theory for mastodon extinction. It is suggested that increased dryness during the present interglacial compared to the climate of earlier interglacials may be the key to unravelling the problem of mastodon extinction in eastern North America.

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Landscape geochemical investigations were conducted upon portions of a natural uniform landscape in southern Norway. This consisted of sampling both soil profile samples and spruce tree twigs for the analysis of twelve chemical elements. These elements were cobalt, copper, nickel, lead, zinc, manganese, magnesium, iron, calcium, sodium, potassium and aluminum which were determined by atomic absorption analysis on standardized extraction techniques for both organic and inorganic materials. Two "landscape traverses" were chosen for a comparative study of the effects of varying landscape parameters upon the trace element distribution patterns throughout the landscape traverses. The object of this study was to test this method of investigation and the concept of an ideal uniform landscape under Norwegian conditions. A "control traverse" was established to represent uniform landscape conditions typical of the study area and was used to determine "normal" or average trace element distribution patterns. A "signal traverse" was selected nearby over an area of lead mineralization where the depth to bedrock is very small. The signal traverse provided an area of similar landscape conditions to those of the control traverse with significant differences in the bedrock configuration and composition. This study was also to determine the effect of the bedrock mineralization upon the distribution patterns of the twelve chemical elements within the major components of the two landscape traverses (i.e. soil profiles and tree branches). The lead distribution within the soils of the signal traverse showed localized accumulations of lead within the overburden with maximum values occurring within the organic A horizon of soil profile #10. Above average concentrations of lead were common within the signal traverse, however, the other elements studied were not significantly different from those averages determined throughout the soils of the control traverse. The spruce twig samples did not have corresponding accumulations of lead near the soil lead anomaly. This is attributable to the very localized nature of the lead dispersion pattern within the soils. This approach to the study of the geochemistry of a natural landscape was effective in establishing: a) average or "normal" trace element distribution patterns b) local variations in the landscape morphology and c) the effect of unusually high lead concentrations upon the geochemistry of the landscape (i.e. within the soil profiles and tree branches). This type of study provides the basis for further more intensive studies and serves only as a first approximation of the behaviour of elements within a natural landscape.

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We studied the association between socioeconomic status (SES), school attended and bone health measured by bone speed of sound (SOS) among adolescent females in Canada. 412 participants from six randomly selected schools in Southern Ontario were examined. Bone SOS was measured by quantitative ultrasound. Participant’s school and aggregate area-based census-derived (AABCD) SES were evaluated as predictors. Mean participant age was 15.7 (SD 1.0) years. Average median family income was $68,162 (SD $19,366). Median family income was non-linearly associated with bone SOS and restricted cubic splines described the relationship. Univariate regression, accounting for clustering of participants in schools, revealed a significant non-linear association between AABCD-median family income and non-dominant tibial SOS (LRT p = 0.031). Multivariable regression revealed school to have a significant impact (LRT p = 0.0001). High schools had a strong influence on the bone health of female students and this effect overrode the effect of SES.

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A wild bee community in southern St. Catharines, Ontario, Canada, was studied from 2003 to 2012 to analyze the effects of primary succession on abundance and diversity. At a former landfill site near Brock University, which previously contained no bees, the number of bees and bee species was expected to increase rapidly following measures to restore the site to grassy meadow habitat. The Intermediate Disturbance Hypothesis (IDH) states that over time, succession occurs. Abundance and diversity increase initially and peak when pioneers coexist with specialized species, then decline because of competitive exclusion. Alternatively, abundance and diversity may continue to increase and stabilize without declining. Bees were sampled repeatedly among years from newer restoration sites (revegetated in 2003), older restoration sites on the periphery of the former landfill (revegetated in 2000), and nearby low disturbance grassy field (i.e. control) sites. In the newer sites, bee abundance and diversity increased then decreased while in older restoration and control sites mainly decreased. This pattern of succession matches the general predictions of the IDH, although declines were at least partially related to drought. By 2006, total bee abundance levels converged among all sites, indicating rapid colonization and succession, and by 2012 diversity levels were similar among sites as well, suggesting that the bee community was fully restored or nearly so within the ten-year study period.

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Pay roll voucher #33 from the Engineer Department of the Welland Railway for the Southern Division for the month of September. (2 copies) [one is signed on the 30th and one on the 31st], Sept. 31, 1857.

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Volunteering as a form of social activity can facilitate older adults’ active aging through community engagement. The purpose of this qualitative case study was to understand the views on older adults’ volunteerism in a community hospital network in Southern Ontario. Utilizing in-depth interviews with 10 older volunteers (over the age of 65), document analysis, and a key informant interview, I explored their experiences of volunteering and social capital development at six hospitals in the network. Data analyses included open and axial coding, and conceptualization of the themes. Four major themes emerged from the data: reasons to volunteer, management’s influence, negative experiences of volunteering, and connections with others. The findings of this research emphasized older volunteers’ strong commitment and enthusiasm to support the hospital in their own communities, the power of volunteering to enhance the development of bonding, bridging, and linking social capital, and the influence of two major contextual factors (i.e. the Auxiliary Factor and the Change Factor) to facilitate or hinder older volunteers’ social capital development in the hospitals. Future research directions should focus on further unpacking the different degrees to which each type of social capital is developed, placing emphasis on the benefits of social capital development for volunteers in healthcare settings. The implications for practice include the targeted recruitment of older adults as healthcare volunteers while creating volunteer positions and environments in which they can develop social capital with their peer volunteers, hospital staff, patients, and people in surrounding communities. To sustain their existing dedicated long-term volunteers, in particular their Auxiliary groups, the community hospital network can enhance facilitating factors such as the Auxiliary Factor while mitigating the negative effects of the Change Factor. By developing social capital through volunteering in their own communities, older adults can engage in active aging, while participating in the development of an age-friendly community.