The rush for land has escalated the last decade, with Sub-Saharan Africa as the most targeted region. Governments, local elites and foreign corporations are increasingly taking control over large areas of agricultural lands with the aim of creating higher financial returns and achieve food security. This phenomenon, known as land grabbing, has received a lot of attention worldwide, not least from non-governmental organizations and scholars stressing the negative impacts on rural farmers and families. Yet, several international organizations as well as many African governments keep advocating the positive effects that land grabbing can have on poverty reduction and economic growth. The dominating capitalist and neoliberal view on development, focusing largely on the economic part, undermines the social and environmental impacts that these investments bring. The purpose of this comparative study is therefore to examine, analyze and compare these impacts in Ghana and Ethiopia, two countries heavily affected by land grabbing. This is done through the lens of political ecology, where concepts such as environmental justice, accumulation by dispossession and sustainable rural livelihoods will be of particular significance. Based on a systematic literature review, the results show that land grabbing projects, said to aim at stimulating economic and social development, have resulted in dispossessions, injustices and environmental conflicts wherein indigenous communities have been deeply affected. Their traditional livelihoods, based mainly on cultivation, fishing, gathering and hunting, have been threatened by several impacts from the land grabs. These include loss of land, declined access to resources, damaged ecosystems, deforestation and lack of alternative ways to maintain food security.

The diploma thesis focuses on problematics connected to the flood and individual kinds of anti-flooding measures in agriculturally used landscape. Theoretical part of the thesis is devoted to the general description of flood problematic. It contains basic terms connected with floods, mentions causes and flood categories, and also the factors that influence it's progress. Thesis includes precautions and solutions of the anti-flood protection. In the practical part of the thesis is characterised chosen region with flood risk. Analysis of the present state includes field research. As a result of the discovered risks have been selected appropriate anti-flood measures for stated location.

La maîtrise de la contamination générée par temps de pluie en milieu urbain constitue un enjeu environnemental important pour limiter la dégradation des milieux aquatiques superficiels. Les outils de modélisation traditionnelle utilisés pour estimer les flux de polluants dans les eaux de ruissellement sont jugés insuffisants dans leur capacité à reproduire les dynamiques des polluants à l’exutoire. Cela est souvent lié au manque de connaissances précises sur les processus en jeu d’une part, et d’autre part aux difficultés d’acquérir des bases de données représentatives et en continu sur des sites réels. Cette thèse a donc pour objectif d’améliorer l’état de la modélisation de la qualité. Elle vise en particulier le développement d’un outil de modélisation conceptuelle de la qualité des eaux de ruissellement à l’échelle du quartier, à partir d’une compréhension approfondie des processus d'accumulation et de lessivage. La simulation des pollutogrammes de matières en suspension (MES) à l’avaloir du bassin versant routier avec les modèles conceptuels d’accumulation-lessivage montre la faible performance des modèles pour estimer les dynamiques d’émissions de MES pour des longues périodes ; la variabilité du processus d’accumulation est le responsable principal de l’inadéquation de ces modèles. L’évaluation de la contribution des retombées atmosphériques sèches à la contamination des eaux de ruissellement en hydrocarbures aromatiques polycycliques (HAPs) et métaux montrent que l’atmosphère ne joue qu’un rôle très mineur dans la contamination des eaux de ruissellement par ces substances. Ainsi le couplage des modèles atmosphériques, qui ne tiennent pas compte des émissions directes liées au trafic, avec les modèles de qualité de l’eau, ne semble pas très pertinent dans l’objectif d’améliorer la prédiction de la contamination des eaux pluviales à l’exutoire. L’investigation à la micro-échelle du mécanisme de lessivage montre que les particules fines sont les plus susceptibles d’être mobilisées par le ruissellement. Cette étude a été menée en utilisant un simulateur de pluie innovant qui présente les avantages d’être mobile et léger, et la possibilité d’avoir des enregistrements en ligne du débit et de la turbidité. Les nouvelles connaissances acquises sur les processus soulignent une grande variabilité qui remet en cause l'intérêt de leur modélisation avec des approches déterministes. Ces connaissances sont intégrées à l’échelle du quartier pour développer un outil de modélisation conceptuelle basé sur une approche stochastique d'estimation de la concentration moyenne de MES et des paramètres de qualité. Le modèle développé est intégré dans le modèle hydrologique URBS. L’application de ce modèle permet d’intégrer la variabilité spatiale et temporelle des émissions en distinguant les contributions de chaque occupation du sol. Les résultats sont prometteurs en termes d’estimation des niveaux de concentration de MES à l’exutoire du bassin versant et de réplication du comportement général de la dynamique de MES, cependant des améliorations peuvent être envisagés pour consolider l’approche et améliorer ses prédictions. La comparaison de ce modèle avec des approches de modélisation empirique globale, conceptuelle semi-distribuée et physique distribuée, montre qu’en termes de pouvoir prédictif et de fiabilité, l’approche URBS-stochastique en parallèle avec l’approche de modélisation physique distribuée sont les plus performantes. En termes de simplicité d’implémentation et d’ajustement entre les observations et les simulations, les approches de modélisation empirique globale et conceptuelle semi-distribuée sont les plus puissantes. A l’issue de cette comparaison, il est clair qu’il n’existe pas un modèle parfait qui couvre toutes les caractéristiques de la modélisation de la qualité des eaux de ruissellement. Le choix de l’approche de modélisation la plus appropriée doit se faire en fonction des objectifs attendus par le modélisateur / Urban runoff contamination is recognized as a major source of the deterioration of the quality of surface water. Commonly used stormwater quality models have poor performance in predicting the pollutant dynamics at the surface outlet, mainly due to the lack of precise knowledge on the governing processes and the difficulties of acquiring representative and continuous databases on real sites. The main purpose of this Ph.D. thesis is to improve the state of stormwater quality modeling. It aims in particular to develop a conceptual modeling tool for stormwater quality prediction at the scale of a city district catchment, based on a deep understanding of the build-up and the wash-off. The application of commonly used stormwater build-up/wash-off models to simulate the dynamics of total suspended solids (TSS) at the outlet of the road catchment suggests that the models poorly replicate the temporal variability of the TSS concentrations unless short periods are considered. The unpredictable nature of the accumulation is largely responsible for the model failure. The evaluation of the contribution of atmospheric dry deposition to stormwater loads for polycyclic aromatic hydrocarbons (PAHs) and metals shows that atmospheric deposition is not a major source of contaminants in stormwater runoff. Thus, linking the air and water compartment in a modeling chain to have more accurate estimates of pollutant loads in stormwater runoff may not be relevant unless the direct traffic emissions are accounted for. The investigation of the wash-off process on elementary surfaces shows that the fine particles are the most likely to be mobilized and transported during a rainfall event. Stormwater samples were collected for this study using an innovative rainfall simulator that allows continuous, on-site monitoring of instantaneous flow and turbidity measurements and that can be easily transported and used on real sites. The new knowledge acquired on the build-up and wash-off processes underlines the great variability of these processes and calls into question their modeling with deterministic approaches. Hence, this knowledge is incorporated into developing a new conceptual stormwater quality model based on the stochastic drawing of event mean concentrations (EMC) of TSS and water quality parameters. The model is integrated within the hydrological model URBS. The application of this approach accounts for the spatial and temporal variability of pollutant emissions by distinguishing the contributions of each land use separately. The obtained results are promising in terms of estimating the concentration levels of TSS at the outlet of the city district catchment and replicating the general behavior of the TSS dynamics. However, improvements can be envisaged to consolidate the approach and improve its predictions. Comparison of this model with global empirical, semi-distributed conceptual and distributed physical modeling approaches shows that in terms of predictive power and stability, the stochastic-URBS and the physically distributed approaches are the most efficient. However, in terms of ease of implementation and best fit between observations and simulations, the global empirical and semi-distributed conceptual modeling approaches are the most powerful. This comparison shows that the perfect model that covers all aspects of stormwater quality modeling does not exist. The choice of the most appropriate modeling approach should mainly be driven by modeling objectives

O objetivo da presente tese é examinar as causas pelas quais a economia brasileira apresentou tão baixo crescimento, em comparação com os demais países e com o seu próprio, depois de ter apresentado tão expressivo crescimento nas primeiras oito décadas do século XX. Ou melhor, por que a economia brasileira não mantém a trajetória que se desenrolava até os anos 1980 de forma a superar a condição de país subdesenvolvido, posteriormente denominado de várias formas, como "em desenvolvimento", "emergente", "NIC". Como objetivo também se arrola a análise sobre se os novos fatores de dinamismo da economia brasileira pós-2004 representam uma mudança qualitativa em relação à trajetória pós-1980. Parte-se do pressuposto de que a economia nacional é parte integrante do sistema produtivo mundial que influi de forma importante sobre ela. Portanto, as causas da mudança de trajetória devem ser buscadas nas características históricas e estruturais da economia brasileira sem deixar de se ter em vista que estas estão entrelaçadas com as mudanças em nível internacional. Por que a integração ao capitalismo gerou dinamismo em algumas regiões e em outras não, quais são as forças propulsoras que determinam o desenvolvimento desigual? Procurar-se-á examinar de forma sucinta as experiências históricas das áreas que ascenderam em detrimento das que permaneceram periféricas ou subdesenvolvidas. As trajetórias dos países hoje centrais e dos periféricos demonstram que não existe um modelo ideal. Ou seja, a ascensão de determinado país decorre do grau de controle sobre a tecnologia, sobre os fluxos financeiros em nível global, sobre o acesso aos recursos naturais e sobre a capacidade militar, entre outros recursos. Na análise da ascensão dessas regiões e nações, verificou-se que as características do capitalismo como um todo se transformam em cada momento, alterando o contexto em que as diversas economias modificam sua posição na economia internacional. Em decorrência, as condições para o desenvolvimento em cada momento adquirem características próprias. E, portanto, as condições sociais e políticas precisam viabilizar políticas, as quais podem mudar ao longo do tempo, mas que favoreçam a acumulação do capital e o desenvolvimento econômico. A fase do capitalismo monopolista que, a partir dos anos 1990, se assenta na proeminência das finanças, e o fim da guerra fria trouxeram novos requerimentos para a ascensão, modificando as formas de polarização. A acumulação resultante implica que a economia brasileira perde a condição de ascender na hierarquia das nações, sendo a intensidade do seu desenvolvimento fortemente condicionada pelos estímulos da economia global. O transcorrer normal da acumulação tende a manter a posição do Brasil na divisão internacional do trabalho, com possibilidade de regressão, a atenuar o seu dinamismo e a inviabilizar sua ascensão, mas não impossibilita a ocorrência de surtos importantes de crescimento como os do atual momento. No entanto, essa trajetória não é predeterminada. Entende-se que um maior dinamismo da economia, que propicie a ascensão, exigirá a reconstituição da capacidade de intervenção do estado nacional. Essa reconstituição passa por uma maior proeminência dos interesses de um conjunto bem mais expressivo da população, restringindo interesses privados. A dificuldade é que o atendimento a esses interesses pressupõe a prevalência de critérios políticos, não podendo, portanto, se basear na pura lógica do capital. Ou seja, defende-se que as restrições à lógica do sistema exigem uma estratégia de desenvolvimento e, portanto, de posicionamento político, que dependerá, para seu sucesso, da capacidade de produzir ao longo do tempo as condições materiais para tal. Esse posicionamento exige, pelas características da atual etapa do capitalismo e da economia brasileira, uma composição política extremamente complexa. / The objective of this thesis is to examine the reasons why the Brazilian economy reported such a low growth comparing with other countries and with its own, after having made such significant growth in the first eight decades of the twentieth century. Or rather, why the Brazilian economy does not keep the path that unfolded until the 1980’s in order to overcome the status of an undeveloped country, after called variously as "developing", "emerging" and "NIC". As an objective, it also a-nalyses whether the new factors of dynamism of the Brazilian economy after 2004 represent a qualitative change in relation to post-1980 history. It assumes that the national economy is an integral part of global production system that influences significantly on it. Therefore, the causes of the change of course must be sought in historical and structural characteristics of the Brazilian economy while having in mind that these are intertwined with changes at the international level. Why the integration of capitalism has generated dynamism in some regions and not others, what are the driving forces that determine the uneven development? Search will examine briefly the historical experiences of the areas that amounted to the detriment of those who remained peripheral or undeveloped. The trajectories of current central and peripheral countries demonstrate that there is no ideal model. That is, the rise of a country derives from the degree of control over technology on financial flows at a global level, on the access to natural resources and military capabilities among other resources. In analyzing the rise of these regions and nations, it was found that the characteristics of capitalism as a whole are transformed at every moment, changing the context in which the different economies change its position in the international economy. As a result, the conditions for the development at any time acquire their own characteristics. Therefore, the social conditions and policies need to enable policies, which may change over time, but that promote capital accumulation and economic development. The stage of monopoly capitalism that from the 1990’s sits on the prominence of finance, and the end of the Cold War brought new requirements for the ascension, changing the forms of polarization. The resulting accumulation implies that the Brazilian economy loses its condition to ascend at the hierarch of nations, and the intensity of its development strongly influenced by stimuli in the global economy. The normal course of accumulation tends to maintain the position of Brazil in the international division of labor, but not major outbreaks of growth as those at the present moment. However this trajectory is not predetermined. It is understood that a more dynamic economy, which triggers the rise, will require the reconstitution of the intervention capacity of the national state. The reconstruction involves a greater prominence of the interests of a more expressive group of the population, restricting private interests. The difficulty is that assistance to those interests presupposes the prevalence of political criteria, and cannot therefore, be based on pure logic of capital. That is, it is argued that the restrictions on the logic of the system require a development strategy and therefore, of political positioning, which relies for its success, on the ability to produce the material conditions for it over time. This position requires, by the characteristics of the current stage of capitalism and the Brazilian economy, an extremely complex political composition.

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MOREIRA, Francisco Giovani Pimentel. Capital imobiliário e a produção urbana de Fortaleza - estudo de caso para o período de 1950-1970. 2004. 108f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Programa de Pós-graduação em Sociologia, Fortaleza (CE), 2004. / Submitted by Gustavo Daher (gdaherufc@hotmail.com) on 2017-08-08T12:26:27Z No. of bitstreams: 1 2004_dis_fgpmoreira.pdf: 463261 bytes, checksum: 3a909abe9b016101ac6e950557c54e1a (MD5) / Approved for entry into archive by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2017-08-08T14:45:55Z (GMT) No. of bitstreams: 1 2004_dis_fgpmoreira.pdf: 463261 bytes, checksum: 3a909abe9b016101ac6e950557c54e1a (MD5) / Made available in DSpace on 2017-08-08T14:45:55Z (GMT). No. of bitstreams: 1 2004_dis_fgpmoreira.pdf: 463261 bytes, checksum: 3a909abe9b016101ac6e950557c54e1a (MD5) Previous issue date: 2004 / The objective of this work is to elaborate and to analyze the paper of the real estate capital, more precisely of the seller of urban lands, in the urbanization process happened in the Fortaleza city, among the decades of 1950 and 1970. For that reason, we chose José Gentil S/A Real estate, whose evidences presented along the study allows us to affirm that it was the most active company in the market of urban lands of Fortaleza, in the considered period, be for the volume of businesses or be for the symbolic power that it contains in itself. We showed a theme- the performance of the Real estate, inserted in movements that concern the growth social- economic of the city, to the exercise in the several ways of power and construction of nets that they create and reproduze the dominance relationships in the extent of a social process of such magnitude , marked by practices (clientelistas, personalistas) and centralizing that they have been giving the tonic of the political and social process in Fortaleza. Finally, founded in the instrumental theoretical that guides us, we showed in an empiric way how the succession of social- economic facts went weaving a favorable scenery the performance of a linked social group to the real estate (fundiário) section, that, owners the economical capital and social prestige, acted with opportunity sense aiming at, before any other thing the wealth accumulation and power, pillars of support of the groups and local dominant classes. / O objetivo deste trabalho é elaborar e analisar o papel do capital imobiliário, mais precisamente dos loteadores de terras urbanas, no processo de urbanização ocorrido na cidade de Fortaleza, entre as décadas de 1950 e 1970. Para tanto, elegemos a Imobiliária José Gentil S/A, cujas evidências apresentadas ao longo do estudo nos permite afirmar que foi a empresa mais atuante no mercado de terras urbanas de Fortaleza, no período considerado, seja pelo volume de negócios, seja pelo poder simbólico que encerra em si mesma. Mostramos um tema-a atuação da Imobiliária, inserido em movimentos que dizem respeito ao crescimento socioeconômico da cidade, ao exercício das várias formas de poder e da construção de redes que criam e reproduzem as relações de dominação no âmbito de um processo social dessa magnitude, marcado por práticas clientelistas, personalistas e centralizadoras que têm dado a tônica do processo político e social em Fortaleza. Finalmente, fundados no instrumental teórico que nos orientou, mostramos de maneira empírica como a sucessão de fatos socioeconômicos foi tecendo um cenário propício a atuação de um grupo social ligado ao setor imobiliário/fundiário, que, municiados pela posse de capital econômico e prestígio social, agiu com censo de oportunidade objetivando, antes de qualquer outra coisa, a acumulação de riqueza e poder, pilares de sustentação dos grupos e classes dominantes locais.

O experimento foi conduzido na Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul durante a estação de outonoinverno, com o objetivo de avaliar os parâmetros produtivos de uma pastagem natural fertilizada com diferentes níveis de N e submetida a diferimento e a sua influência sobre a produção animal. A fertilidade do solo foi corrigida 7 anos antes deste experimento (1996) com calcário e adubação de P e K. A área experimental foi roçada e diferida em 15/01/2003, quando foram aplicados os três níveis de nitrogênio (zero, 50 e 100 kg N/ha/ano). O período experimental ocorreu de 15 de abril (entrada dos animais) a 1º de setembro (final do inverno). Foram utilizados novilhos de sobre-ano (18 meses) em lotação contínua com carga variável de forma a manter uma oferta média de forragem de 10 kg de MS/100 kg PV/dia. O delineamento utilizado foi o de blocos completos casualizados com parcelas subdivididas no tempo sendo o tempo considerado na parcela principal e o N na subparcela. A pastagem nativa fertilizada quando diferida no verão por um período de 90 dias permite manter altas cargas animais durante o outono e inverno e em níveis crescentes conforme a adubação nitrogenada (958, 1072 e 1443 kg PV/ha, para zero, 50 e 100 kg N/ha respectivamente). Este efeito é devido fundamentalmente às taxas de crescimento observadas durante o período de diferimento. A performance animal somente é adequada durante o primeiro mês de utilização do pasto, ocorrendo perdas de peso a partir de meados de maio. Os níveis de nitrogênio utilizados não contribuem para atenuar estas perdas. Ainda assim é possível chegar ao final do inverno com o mesmo peso individual inicial dos animais. O diferimento de áreas de pastagem natural adubada revela-se uma estratégia interessante dentro de sistemas de produção animal a pasto, desde que integrado num planejamento forrageiro global da propriedade. / The experiment was conducted at the Agronomic Experimental Station of Federal University of Rio Grande do Sul, at Eldorado do Sul district, during the autumn-winter seasons of 2003, aiming the evaluation of the parameters of natural pasture and animal production at different levels of nitrogen fertilization and submitted to deferment. Soil fertility was amended seven years before this trial (1996) with limestone and P and K fertilizers. Experimental area was mowed and deferred in 15/01/2003, when three levels of nitrogen fertilization (zero, 50, 100 kg N/ha) were applied. Evaluation period extended from April 15th (beginning of grazing period) to September 1st (final of winter), using eighteen months steers in continuous grazing an variable stocking in order to maintain average dry matter (DM) allowance of 10 kg DM/100 kg LW/day. A randomized complete block design with two replications was utilized, with time considered as main plot and N as sub-plot. Deferring fertilized native pasture at mid summer by 90 days make possible to maintain high stocking rates during the critical autumn-winter period dependent on nitrogen level (958, 1072 e 1443 kg LW/ha, for zero, 50 e 100 kg N/ha respectively). This differential effect is due to the forage growth rate verified during rest period. Animal performance was adequate only during the first month of pasture utilization and losses occur after mid may. The utilized N levels do not contribute to avoid these losses. Instead the observed weight losses, it is possible to keep the animals with the same initial weight of the beginning of autumn by the final of the winter. Deferring areas of natural pasture is a useful strategy inside animal production systems, if integrated on a global feed budget.

Le phénomène de défaillance par fatigue peut apparaitre à des niveaux de contraintes éloignés du seuil de dimensionnement statique de mécanique des milieux continus, tout simplement du fait que l’endommagement suit un processus complexe et de longue haleine. Disposer d’outils performants de prévision de durée de vie en fatigue est donc une nécessité de conception pour le dimensionnement des machines, composants, structures, par natures soumises à des sollicitations variables dans le temps, liée à leur utilisation en service. Pour contribuer à cet objectif nous nous sommes attachés à une conception concernant les outils les plus fréquemment utilisés pour ces prévisions en fatigue : les critères multiaxiaux de fatigue et les lois d’endommagement et de cumul en fatigue. La première partie du travail effectué a consisté en une étude de validité et d’analyse de nouveaux critères de fatigue multiaxiaux proposés depuis une dizaine d’années. Cette validité est comparée vis-à-vis de celle des critères implantés dans l’industrie. L’approche intégrale dont le principe est l’établissement du caractère endommageant d’un cycle multiaxial par la contribution des sollicitations présentes sur tous les plans physiques et non un seul comme le cas de l’approche « plan critique », est la plus efficace en règle générale pour traduire correctement le comportement en fatigue sous chargement multiaxial. L’intégration d’une démarche probabiliste proposée permet d’associer la probabilité de survie aux résultats de calcul d’un critère. La seconde partie de cette thèse a conduit à proposer de nouveaux modèles différentiels d’endommagement permettant de retrouver, dans le cas d’un chargement d’amplitude constante, le formalisme classique des courbes S-N des matériaux (Wöhler, Basquin, Bastenaire et Stromeyer). L’influence de l’ordre d’apparition des cycles de contraintes, les valeurs moyennes, l’évolution non linéaire du dommage par fatigue sont ainsi prises en compte. Le problème de sensibilité du modèle et donc ses prévisions de durée de vie en fatigue uniaxiale d’amplitude variable, comme cela est rencontré dans le modèle de Chaboche, est ainsi écarté. La confrontation du modèle proposé pour les courbes S-N de Basquin et Bastenaire est prometteuse en terme de prévision de duré de vie. Une étude comparative par rapport à la loi de Miner, prise comme référence, avec celles proposée et de Mesmacque & Amrouche à donnée des résultats concluants pour les lois à évolution non linéaire. / The phenomenon of failure by fatigue can apparaitre at levels of stress remote from the threshold of static dimensinnaly of mechanics of the continuous medium, simply because the damage follows a complex and longterm process. Have successful tools of forecast of life expectancy in fatigue is thus a necessity of conception forthe dimensionnly of machines, components, structures, by natures subjected to requests time-varying, connected to their use in service. To contribute to this objective we became attached to a conception concerning tools most frequently used for these forecasts in fatigue: The multiaxial criteria of fatigue and the laws of damage and of cumul in fatigue. The first part of the made work consisted of a study of validity and analysis of new multiaxial criteria of fatigue proposed since around ten years. This validity is compared towards that of the criteria implanted in the industry. The integral approach the principle of which is the establishment of the character damaging of a multiaxial cycle by the contribution of the sollicitation on all the physical plans and not the only one as the case of the approach " critical plan", is the most effective as a general rule to translate correctly the behavior into fatigue under multiaxial load. The integration of a proposed probability approach allows to associate the probability of survival with the results of calculation of a criterion. The second part of this thesis led to propose new differential models of damage allowing to find, in the case of a load of constant amplitude, the classic formalism of the curves S-N of materials (Wöhler, Basquin, Bastenaire and Stromeyer). The influence of the order of appearance of cycles of stress, the mean values, the not linear evolution of the damage by fatigue are so taken into account. The problem of sensibility of the model and thus its forecasts of life in fatigue uniaxiale of variable amplitude, as it is met in the model of Chaboche, is so pushed aside. The confrontation of the model proposed for the curves S-N of Basquin and Bastenaire is promising in term of forecast of the life. A comparative study with regard to the law of Miner, taken as reference, with those proposed and of Mesmacque and Amrouche with datum of the decisive results for the laws with not linear evolution.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research is based on a plastic practice, with the objective of construct a pictorial field through the operative concepts of accumulations and contrapositions. In its development, articulated plastic practice, based on notes made in diary of notes, with the theory, history and art criticism, and written in visual poetics. This research is established to investigate the principles that condition the instauration of my works. Thus, I begin to reflect the working documents, analyze the origin and formation of accumulations of pictorial material and its relationship with the experimental deviations, what and how the simulations and the real three-dimensional elements are opposed to the picture, coming to strategies, in which I investigate how the procedures of appropriation, collage, fusion of elements are used for work s construction. Still, do an analysis on my works, making comparisons with my previous productions, and the work of Iberê Camargo, Nuno Ramos, Leda Catunda, plus other artists with whom my work dialogues, in order to understand the developments of some procedures and my expressive intention. I conclude this study by answering the questions about the relationship and influences between painting and three-dimensional elements, and pointing possible ways to continuation of this work. / A presente pesquisa baseia-se na minha produção plástica, com o objetivo de construir um campo pictórico por meio dos conceitos operatórios de acúmulos e contraposições. No seu desenvolvimento, articulei a prática plástica, baseada em apontamentos realizados em um diário de anotações, com a teoria, a história e a crítica de arte, além de escritos em poéticas visuais. O estabelecimento dessa pesquisa se dá por meio da investigação aos princípios que condicionam à instauração das minhas obras. Assim, inicio a reflexão pelos documentos de trabalho, analiso a origem e a constituição dos acúmulos de matéria pictórica e suas relações com os desvios experimentais, quais são e como as simulações do real e os elementos tridimensionais se contrapõem ao pictórico, até chegar às estratégias, em que investigo como os procedimentos de apropriação, colagem, hibridizações e mestiçagens são utilizados na construção dos trabalhos. Empreendo ainda, uma análise sobre as minhas obras, estabelecendo comparações com minhas produções anteriores, e com o fazer de Iberê Camargo, Nuno Ramos, Leda Catunda, além de outros artistas com os quais o meu trabalho dialoga, a fim de se compreender os desdobramentos de alguns procedimentos e a minha intenção expressiva. Encerro essa pesquisa respondendo às questões em torno das relações e influências entre a pintura e os elementos tridimensionais, e apontando possíveis caminhos para a sequência desse trabalho.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of pig slurry as a source of nutrients can affect the conditions of acidity and nutrient availability, altering the environment for crop development. The objective of this study was to evaluate changes in chemical properties of an Alfisol after 95 months of cultivation and 19 applications of pig slurry, conducted under no-tillage system. The experiment was installed in May 2000, an experimental area under no-tillage at the Federal University of Santa Maria, and conducted until January 2008. The experimental design was a randomized block design with three replications. Were performed nineteen surface applications of 0, 20, 40 and 80 m3 ha-1 of pig slurry during the experiment and in the end, were collected samples of soil layers of 0-2, 2-4, 4 -6, 6-8, 8-10, 10-12, 12-14, 14-16, 16-18, 18-20, 20-25, 25-30, 30-35, 35-40, 40-50 and 50-60 cm depth. The soil was collected with the aid of a spade cut-off, air dried, milled manually with the aid of a roller and passed through a sieve with 2 mm mesh and reserved. It was determined the pH values in water (1:1), SMP, the levels of exchangeable Al, Ca, Mg and K. With the data obtained were calculated the sum of bases, base saturation and Al saturation, CEC pH7, CEC effective and potential acidity (H + Al). Were also determined the total contents of N, P and K, levels of mineral N, available P and soil organic matter. The successive application of pig slurry promoted increase in pH values in water up to 8 cm of soil, however, no change in potential acidity. Also caused increased levels of exchangeable Ca and Mg in the surface layers of soil, reflecting an increase in the values of sum of bases, base saturation and decreasing Al saturation. Furthermore, the applications over time caused an increase in levels of soil organic matter, reflecting in increased levels of total N to a depth of 30 cm. Applications of manure resulted in increased levels of available P and exchangeable K to a depth of 60 cm, while for the total P increases were observed up to 30 cm depth. The changes observed in soil chemical properties provides better environment for root development of crops due to lower acidity and higher nutrient availability in soil solution. However, one must be careful in extrapolating these results to different soils, although the phenomena are similar, they occur in different magnitudes depending on soil characteristics. / A utilização de dejeto líquido de suínos como fonte de nutrientes pode afetar as condições de acidez e de disponibilidade de nutrientes, modificando o ambiente para o desenvolvimento das culturas. O objetivo do presente trabalho foi avaliar as alterações nos atributos químicos de um Argissolo após 95 meses de cultivo e 19 aplicações de dejeto líquido de suínos, conduzido sob sistema de plantio direto. O experimento foi instalado em maio de 2000, numa área experimental sob sistema plantio direto na Universidade Federal de Santa Maria, e conduzido até janeiro de 2008. O delineamento experimental foi de blocos ao acaso com três repetições. Foram realizadas dezenove aplicações superficiais de 0, 20, 40 e 80 m3 ha-1 de dejeto líquido de suínos, durante a condução do experimento e, ao final, foram coletadas amostras do solo nas camadas de 0-2, 2-4, 4-6, 6-8, 8-10, 10-12, 12-14, 14-16, 16- 18, 18-20, 20-25, 25-30, 30-35, 35-40, 40-50 e 50-60 cm de profundidade. O solo foi coletado com o auxílio de uma pá-de-corte, seco ao ar, moído manualmente com o auxílio de um rolo destorroador e passado em peneira com malha de 2 mm e reservado. Foram determinados os valores de pH em água (1:1), índice SMP, os teores trocáveis de Al, Ca, Mg e K. Com os dados obtidos foram calculadas a soma de bases, saturação por bases e por Al, CTC pH7,0, CTC efetiva e acidez potencial (H+Al). Também foram determinados os teores totais de N, P e K, os teores de N mineral, P disponível e matéria orgânica do solo. A aplicação sucessiva de dejeto líquido de suínos promoveu incremento nos valores de pH em água do solo até 8 cm, no entanto, não houve alteração nos valores de acidez potencial. Também provocou aumento nos teores trocáveis de Ca e Mg nas camadas superficiais do solo, refletindo em aumento nos valores de soma de bases, saturação por bases e diminuindo a saturação por alumínio. Além disso, as aplicações ao longo do tempo promoveram aumento nos teores de matéria orgânica do solo, até 60 cm de profundidade, refletindo em aumento nos teores de N total até a profundidade de 30 cm. As aplicações de dejeto provocaram incremento nos teores de P disponível e K trocável até a profundidade de 60 cm, enquanto que para o P total os incrementos foram observados até 30 cm de profundidade. As alterações observadas nos atributos químicos do solo proporcionam melhor ambiente para o desenvolvimento radicular das culturas devido à redução da acidez e maior aporte de nutrientes na solução do solo. No entanto, deve-se tomar cuidado ao extrapolar esses resultados para solos com características diferentes, embora os fenômenos se assemelhem, estes ocorrem em magnitudes diferentes dependendo das características do solo.