Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia Oceânica, Escola de Engenharia, 2009. / Submitted by Lilian M. Silva (lilianmadeirasilva@hotmail.com) on 2013-04-20T19:57:52Z No. of bitstreams: 1 Estudo das propriedades químicas dos rejeitos de dragagem para utilização como solo fabricado para fins agrícolas.pdf: 3400808 bytes, checksum: ee6262b434d2d3a9593672ab06f9c86b (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-06-04T19:12:49Z (GMT) No. of bitstreams: 1 Estudo das propriedades químicas dos rejeitos de dragagem para utilização como solo fabricado para fins agrícolas.pdf: 3400808 bytes, checksum: ee6262b434d2d3a9593672ab06f9c86b (MD5) / Made available in DSpace on 2013-06-04T19:12:49Z (GMT). No. of bitstreams: 1 Estudo das propriedades químicas dos rejeitos de dragagem para utilização como solo fabricado para fins agrícolas.pdf: 3400808 bytes, checksum: ee6262b434d2d3a9593672ab06f9c86b (MD5) Previous issue date: 2009 / A dragagem pode ser considerada como o ato de retirada de material do leito dos corpos de água, principalmente para o aprofundamento e alargamento de canais em rios, portos e baías,construção de diques, fundações para pontes e outras estruturas. Devido à necessidade de navegação de grandes embarcações no Porto do Rio Grande, periodicamente é necessária a realização de dragagens. A pesquisa com material dragado é feita devido ao potencial econômico do rejeito gerado e ao problema ambiental gerado por ele. É importante desde o projeto da obra, o conhecimento das características físico-químicas dos sedimentos. A natureza de contaminantes em materiais dragados varia muito, dificultando as considerações sobre usos benéficos do rejeito, e embora algumas vias navegáveis estejam localizadas próximas a áreas industrializadas ou centros urbanos, a maior parte do material dragado é considerada não contaminada. A caracterização do material dragado para uso como fertilizante é feita pela determinação de matéria orgânica, pH, salinidade, N, P, K, Ca, Mg,metais pesados e Capacidade de Troca Catiônica (CTC), que depende do pH e diretamente proporcional a concentração de argila, conteúdo de matéria orgânica e sua granulometria.Foram feitas análises químicas para a determinação de contaminantes na lama (segundo o CONAMA), e análise de fertilidade do solo (Comissão de Química e Fertilidade do Solo RS/SC) para o estudo da sua utilização. Assim, o estudo do resíduo do material dragado é de suma importância tanto para os custos da operação, quanto para o aproveitamento desse material e cuidado com o meio ambiente. O resíduo estudado foi depositado em bacias de sedimentação em 2001, onde em 2006 mostrou um grande desenvolvimento de vegetação na área que a lama foi depositada, indicando o potencial do resíduo, que foi comprovado pelas análises. / Dredging may be considered as the act of removal of material from the bed of the water bodies, mainly to the deepening and widening of channels in rivers, harbors and bays, construction of dams, foundations for bridges and other structures. Due to the need for navigation of large vessels in the Port of Rio Grande, it is periodically necessary to carry out dredging. The research with dredged material is carried out due to the economic potential of the waste generated and the environmental problem created by it. It is important since the project, the knowledge of the physicochemical characteristics of sediments. The nature of contaminants in dredged material varies widely, making it difficult the comments on the beneficial uses of waste, and although some waterways are located close to industrial areas or urban centers, most of the dredged material is not considered contaminated. The characterization of dredged material for use as fertilizer is made by the determination of organic matter, pH, salinity, N, P, K, Ca, Mg, heavy metals and cation exchange capacity (CEC), which depends on the pH and is directly proportional to concentration of clay, content of organic matter and its granular size. Chemical analyses were performed for the determination of chemical contaminants in the mud (according to CONAMA), and analysis of soil fertility (Commission of Chemistry and Soil Fertility RS / SC) for the study of its use. Thus, the study of the residue of the dredged material is of great importance for the costs of operation, for the use of this material and for care with environment. The waste studied was deposited in basins of sedimentation in 2001. In 2006 this area showed a great development of vegetation where that the mud was deposited, indicating the potential of the residue, which was proven by analyses.

The growing South African domestic organic food industry is a new feature of the recent structural shifts in food demand in the country. Consumer demand preferences for organic food impact on agricultural production methods due to the unintended positive consequences of improved soil fertilisation, increased productivity and increased use of indigenous knowledge. Understanding consumer demand for food, specifically organic food, in South Africa is becoming increasingly important as consumers’ attitudes and preferences strongly influence the direction of food retailers’ strategies. This study used a single bound dichotomous choice contingent valuation method (CVM) to analyse the determinants of organic food in SA, specifically organic fruit juice and wine. Data was collected from a CVM questionnaire administered to 550 respondents in a food retail store over 3 days. Findings from this study indicate consumers believe organic food is more nutritious and tastier than conventional food, organic agriculture benefits both small-scale and local farmers and that consumers require a guarantee of the organic origin of organic products. Emphasising these benefits and directly referring to the small-scale and local farmers from whom organic products have been procured in advertisement campaigns may improve retail marketing strategies for organic food. It also highlights that South African policy makers urgently have to finalise the promulgation of the draft legislation on organic standards to provide certainty to local consumers and hence a positive signal to current and prospective investors in the local organic industry. Empirical results from this study show that socio-demographic factors do influence consumer demand and supports the need for disaggregated food demand analysis in South Africa. Socio-demographic factors do influence South African consumers’ decision to purchase organic food and younger age increases the probability of the decision to purchase organic food; whereas being married and being in possession of non-formal training qualifications decreases this probability. Organic consumer awareness and education programmes should therefore be targeted at older, unmarried consumers with high levels of formal education. The domestic market may provide a niche for South African wine producers as this study showed that the majority of respondents interviewed are prepared to pay higher premiums for organic wine. A limitation of this study is that these results may reflect consumers’ demand for wine as a luxury good as no separate analysis and questions were included on consumer demand for wine. Policy makers should support small-scale producers and black vintners in the Western Cape to exploit growing organic wine industry by conducting further research for a organic wine marketing campaign that brands organic wine highlighting procurement from small-scale producers, local farmers and positive contribution to environment, providing extension services to small-scale producers on organic wine production, investing in research and development in organic wine production facilitating mentorship between small-scale farmers and existing organic wine producers and lobbying national department of agriculture to finalise the draft South African organic standard given that South African consumers require guarantee of organic origin. Agents in the private sector may exploit opportunities in the organic wine industry by targeting consumers that are younger and old age of Christian faith, lobby the South African government to finalise the draft organic standard, highlight attitudes that organic wine contribute positively to the environment, local and small-scale farmers in organic wine marketing campaigns and procure more organic wine from small-scale and local organic wine producers. Local and small-scale fruit producers and fruit processors in the Western Cape are well positioned to exploit growth forecasted in the domestic organic fruit juice sector given its global reputation for producing high quality fruit, proven manufacturing capabilities and expertise in fruit juice production. Both younger and older age positively influences willingness to pay for organic fruit juice but younger consumers are willing to pay higher prices than older consumers for organic fruit juice. Consumers that are the head of households, by being in the position of food purchaser, are also willing to pay higher prices for organic fruit juice. Afrikaans speaking consumers, 77 percent belonging to the coloured population group of which 69 percent earn less than an average monthly income of R3500 are less likely to pay higher prices for organic fruit juice due to lower disposal incomes. South African citizens that represent almost 90 percent of the Western Cape population are concerned about environmental issues confirmed by beliefs that organic food contributes to the environment, small-scale and local farmers. This concern is expressed in the higher prices that South African citizens are willing to pay for organic fruit juice. These empirical findings indicate the target consumers that organic fruit juice marketing campaigns should focus on. Specific policy interventions to promote the industry include public investment in research and development in organic production methods, extension service provision on organic production methods to small-scale farmers and development of mentorship programmes between existing small-scale and existing organic producers. Copyright / Dissertation (MInstAgrar)--University of Pretoria, 2009. / Agricultural Economics, Extension and Rural Development / unrestricted

When analyzing the road network of the country, it is noticed that the extension of paved roads is very small. This fact is mainly due to reduced public resources and the high costs of traditional materials utilized in the paving of roads. Increasingly performing pavements requires the utilization of local materials, which do not always have the technical properties that meet the valid standards. Thus, it is necessary the search for products or mechanisms that improve these features and that make possible the utilization of local materials to replace conventional materials. The use of cement has been, long-standing, a good additive to improve the properties of soils. This dissertation presents the results of a saprolite soil of volcanic rock, improved with cement, located in the city of Silveira Martins-RS, for application as base layer in roads of low traffic volume. The analysis seeks to avail of the concepts of Soil Mechanics along with knowledge of the Mechanical Pavement. In this research were performed, among others, characterization tests, soil classification, determination of the California Bearing Ratio (CBR), Compressive Strenght (CS), Indirect Tensile Strength (ITS) and triaxial tests of repeated loads to determine the Resilient Modulus (RM). With the results of the tests cited, it was held the mechanistic analysis, through the SisPav program in order to analyze the potential use of improved soil with cement in substitution of a conventional material. The results demonstrate that the use of these studied soils meet the normative specifications and have great potential for utilization as bases of pavement on highways with low traffic volume. / Ao analisar a malha rodoviária do país, percebe-se que a extensão de rodovias pavimentadas é muito pequena. Este fato deve-se, principalmente, aos reduzidos recursos públicos e aos altos custos dos materiais tradicionais empregados na pavimentação de rodovias. Cada vez mais a execução de pavimentos necessita da utilização de materiais locais, que nem sempre apresentam as propriedades técnicas que atendam as normas vigentes. Sendo assim, faz-se necessário a busca de produtos ou mecanismos que melhorem essas características e que tornem viável a utilização dos materiais locais em substituição aos materiais convencionais. A utilização de cimento já é de longa data, um bom aditivo para melhorar as propriedades de solos. Esta dissertação apresenta os estudos de um solo saprolítico de rocha vulcânica, melhorado com cimento, localizado na cidade de Silveira Martins-RS, para sua aplicação como camada de base em rodovias de baixo volume de tráfego, valendo-se dos conceitos da Mecânica dos Pavimentos Nesta pesquisa foram realizados, entre outros, ensaios de caracterização, classificação do solo, determinação do Índice de Suporte Califórnia (ISC), Resistência à Compressão Simples (RCS), Resistência à Compressão Diametral (RCD) e ensaios triaxiais de cargas repetidas para determinação do Módulo de Resiliência (MR). Com os resultados dos ensaios citados realizou-se a análise mecanicista, através do programa SisPav, a fim de investigar o potencial emprego do solo melhorado com cimento em substituição a um material convencional. Os resultados demonstram que a utilização do solo estudado atende as especificações normativas e apresenta grande potencialidade para utilização como base de pavimento em rodovias com baixo volume de tráfego.