<p> Sediment samples were taken from the exposed facies of two quarries north of Burford Ontario. The samples were then dry sieved and the results were plotted as frequency histograms to show the type and quantity of sediment present. Moreover, measurements of soil tongues, sand lenses and strata depths were recorded to provide a comprehensive understanding of the depositional history and processes.</p> <p> The above research was then combined with the present day comprehension of the depositional history of southern Ontario. The conclusions reached in this paper are useful, as they contribute and improve the understanding of the depositional history of southern Ontario.</p> / Thesis / Candidate in Philosophy

Machair is a habitat found predominantly in coastal areas of the north–west of Scotland and is characterised by a low-input, rotational arable system interspersed with semi-natural grasslands. Land management is an essential part of the machair system as both intensification and abandonment threaten its future. Little is known about this system in terms of its below ground communities. A survey was conducted over a three season, two year period for molecular determination of bacterial, AM fungal and nematode community structure. Cropped, fallow and undisturbed grassland were sampled; soil and roots associated with two commonly occurring species and composite soil samples were collected. In addition the effect of edaphic factors and vegetation composition on soil communities was assessed, both in the field and in greenhouse experiments. Results show that although all of the examined factors impacted the community structure of the three soil groups to some degree, the strength of this effect varied between groups. Bacterial communities were mainly affected by temporal factors, particularly year, possibly due to variation in soil moisture content. AM fungal community structure also varied considerably with season, but the mechanisms behind this were less obvious, with both abiotic and plant factors playing a role. AM fungal community structure varied with different plant hosts but also with soil moisture content. In contrast to both bacteria and AM fungi, nematode communities showed a strong response to land use although temporal factors and differences between locations were also observed. Grasslands harboured a distinctly different community structure from cropped and fallow, largely as a result of variation in bacterivores and carnivores. Vegetation composition and soil moisture content were also found to affect nematode community structure. This study has revealed that machair soil communities seem to be highly complex, dynamic and adapted to the changeable conditions that persist.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Desde que o homem descobriu na agricultura uma forma de obter alimentos, a natureza passou a ser modificada. AlteraÃÃes foram causadas no ecossistema e com elas vieram as perdas na qualidade do solo. Com isso, sentiu-se a necessidade da implantaÃÃo de sistemas que preconizam pela conservaÃÃo do solo e, dessa forma, os resÃduos que antes eram queimados ou retirados da Ãrea agrÃcola comeÃam a ser deixados na superfÃcie do solo com o intuito de protegÃ-lo e promover melhorias na sua qualidade. Nesse contexto, a aplicaÃÃo de resÃduo orgÃnico no solo, como o bagaÃo de caju, pode trazer benefÃcios à qualidade fÃsica do mesmo. Diante do exposto, o objetivo da pesquisa foi avaliar o efeito da aplicaÃÃo de resÃduo de caju sobre a qualidade fÃsica do solo por meio de indicadores. Foram coletadas amostras de solo com estrutura preservada e nÃo preservada. As anÃlises foram determinadas em campo (infiltraÃÃo e condutividade hidrÃulica) e em laboratÃrio (Ãndice S e permeabilidade do solo ao ar). O delineamento empregado foi o de blocos ao acaso, composto por 5 tratamentos (cinco nÃveis de aplicaÃÃo â 0, 1, 2, 3, 4, que corresponde, respectivamente a: testemunha, 16, 32, 48, 64 t ha-1 de resÃduo orgÃnico) e quatro blocos. Para a anÃlise estatÃstica, verificou-se a normalidade dos dados a partir do teste de Kolmogorov-Smirnov e, em seguida, realizou-se a anÃlise de variÃncia e o teste Tukey a 5 % de probabilidade. Os valores condutividade hidrÃulica em solo saturado (K0) estiveram na faixa que variou de alta a muito alta, reduzindo a possibilidade de escoamento superficial. O resÃduo nÃo influenciou na retenÃÃo de Ãgua no solo, mesmo em doses elevadas. O Ãndice S mostrou valores acima dos considerados pela literatura (>0,035), sugerindo um bom indicador na qualidade estrutural do solo em estudo. A permeabilidade do solo ao ar (Kar) tambÃm demonstrou valores muito acima daquele considerado crÃtico (> 1Âm2), nÃo sendo, portanto, restritivo ao crescimento das plantas. à possÃvel afirmar que os resultados elevados K0, Ãndice S e Kar estiveram intimamente relacionados com a macroporosidade, caracterÃstica inerente ao solo utilizado nessa pesquisa. As doses crescentes de resÃduo de caju nÃo influenciaram significativamente nos resultados supracitados. / Since man discovered agriculture as a way to get food, nature has been modified. Changes were caused in the ecosystem and with them came the losses in soil quality. Therefore, it was presumed the need to implement systems that imply on the conservation of soil and thus the plant residues that were burned or removed from the agricultural area started to be left on the soil surface in order to protect the soil and to promote improvements in their quality. In this context, the application of plant residues on the soil, such as cashew residues, can bring benefits to physical quality of the soil. Given this, the present research objective was to evaluate the effect of cashew residue on soil physical quality measured through indicators. Samples were collected from both undisturbed not preserved soil. The analyzes were determined in the field (infiltration and hydraulic conductivity) and in the laboratory (index S and soil air permeability). The experimental design was randomized blocks, consisting of 5 treatments (five application rates: 0, 1, 2, 3, 4, which correspond, respectively, to: control, 16, 32, 48, 64 t ha-1 organic waste) and four blocks. For statistical analysis, it was verified the normality of data from the Kolmogorov-Smirnov and, then, followed by the analysis of variance and Tukey test at 5% probability. The values for saturated hydraulic conductivity (K0) was found to be in the range varying from high to very high, with reducing the possibility of superficial runoff. The residue did not affect the soil water content, even at high rate applications. The S index showed values above those shown in the literature (> 0.035), suggesting a good indicator of the soil quality under study. The soil air permeability (Kar) also had values above that considered critical (> 1&#956;m2), being, therefore, limiting to plant growth. It can be argued that the high results K0, S and Kar were closely related to macroporosity, inherent characteristic of the soil used in this research. Increasing application rates of cashew residues did not significantly influence the above results.