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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The morphodynamic characteristics of erosional headcuts in Palmiet (Prionium serratum) wetlands

Williams, Afeefah January 2018 (has links)
>Magister Scientiae - MSc / Gully erosion and headcut migration has been at the crux of wetland degradation in South Africa. The resulting erosion and draining effect has seen more than 50% of wetlands in the country degraded. This study investigated the degradation of indigenous Palmiet, peat forming, wetlands through headcut erosion. This was done by exploring the relationship between headcut migration rate and morphodynamic characteristics through the use of multiple regression analysis. Wetlands investigated in this study occurred in the Kromme River catchment and Nuwejaars River catchment, in the Eastern Cape and Western Cape respectively. Morphodynamic characteristics assessed include headcut dimensions, gully characteristics, soil characteristics and drainage basin characteristics. These parameters were determined either through infield assessment, image analysis or laboratory analysis. Three headcut migration rate types were calculated through a combination of infield measurements and image analysis techniques executed within ArcGIS. These migration rate types include apex advancement (m/a), gully expansion (m2/a) and volume erosion (m3/a). Statistical analysis revealed significant relationships between morphodynamic characteristics and both volume erosion and gully expansion. Morphodynamic characteristics such as drop height, apex width, gully width, drainage rate and sand content were found to have a direct relationship with migration rates, whereas characteristics such as average drainage basin slope, clay content, silt content, SOM content and soil saturation were found to have an indirect relationship with headcut migration rates. Results provide insight into the headcut migration process, its influencing factors and the potential for headcut migration rate prediction. An evaluation of these results using WET-Health found that the wetland management tool captures wetland geomorphic controls to an accuracy of 68% and 70%. Furthermore, the influence of morphodynamic characteristics on migration rates contributes to the wetland rehabilitation process as it allows for the identification of headcut sites most susceptible to erosion. This will then allow for timely wetland rehabilitation, decreasing the rate of net wetland degradation and improving the management and efficiency of wetland restoration.
2

Os recrutamentos militares e as relações sociedade-Estado na Capitania/Província de São Paulo (1765-1828) /

Silva, Karina da. January 2007 (has links)
Orientador: Marisa Saenz Leme / Banca: Wilma Peres Costa / Banca: Denise Aparecida Soares de Moura / Resumo: Os recrutamentos militares foram uma realidade na Capitania de São Paulo, desde o século XVIII. Os conflitos na Bacia do Prata, na busca de delimitar as fronteiras da América portuguesa e espanhola, exigiram a organização de uma estrutura militar no Brasil. Para sediar essa estrutura foi escolhida a referida Capitania. A união de interesses, de segmentos da elite paulista e da Coroa portuguesa, possibilitou a consolidação da militarização da Capitania ao longo da segunda metade do século XVIII. Todavia, a dinamização da economia e da sociedade paulista, a partir das últimas décadas do século XVIII e início do XIX, entrou em conflito com a militarização ali desenvolvida. O presente trabalho buscou analisar as diferenças entre os recrutamentos realizados em São Paulo nesses dois momentos, focando as relações entre a sociedade e o Estado na organização e manutenção da estrutura militar. / Abstract: The military recruitment had been a reality in São Paulo, since the 18th century. The conflicts at the Silver Drainage Basin, in search to delimit the Portuguese and Spanish America borders, they had demanded to orgazine the military structure in Brazil. Hosting this structure São Paulo Captainship was chosen. The union of interests, segments of São Paulo’s elite and the Portuguese Crown, made it possible the militarization of Captainship consolidation throughout the second half of 18th century. However, the joining of the economy and the paulista society, from the last decades from the 18th and beginning of 19th century, it got in conflict with the militarization developed there. The current paper searched to analyze the differences between the recruitment fulfilled in São Paulo at these two moments, focusing the relations between the society and the State over the organization and maintenance of the military structure. / Mestre
3

Nutrient transport modelling in the Daugava River basin

Wallin, Andrea January 2005 (has links)
<p>Övergödning utgör ett av de allvarligaste hoten mot Östersjöns miljö. Storleken av näringsbelastningen till havet behöver därför bestämmas med hjälp av tillgängliga matematiska modeller. Modellen ”Generalised Watershed Loading Functions” (GWLF), en ickedistribuerad parametermodell som uppskattar hydrologi och månatlig näringsbelastning, tillämpades på avrinningsområdet till Daugava som mynnar i Östersjön. Syftet med studien var att genom modellering av historisk transport av näringsämnen till Östersjön ta fram parametrar och indata som sedan kan användas vid applicering av GWLF på omkringliggande avrinningsområden. Data från 1990-talet användes för kalibrering av modellen och data från 1980-talet för validering. Årlig kvävebelastning modellerades med R2värdet 0,78 för kalibreringsperioden. Modellerad årlig kvävebelastning för valideringsperioden underskattades med ungefär 30 % vilket troligen beror på att kvävekoncentrationer i grundvatten och ytavrinning minskade mellan 1980- och 1990-talen.</p><p>Fosforbelastningen underskattades jämfört med rapporterade värden vilket troligen beror på att enskilda avlopp inte inkluderades och att rapporterade punktutsläpp är för låga.</p><p>Modifikationer av modellen föreslås för prediktion av näringsbelastningar under lång tid och behovet av harmoniserad, uppdaterad och lättillgänglig data för näringstransportsmodellering diskuteras.</p> / <p>Eutrophication is one of the most serious threats to the Baltic Sea environment. Nutrient loading into the sea therefore needs to be quantified by available mathematical models. The Generalised Watershed Loading Functions (GWLF), a lumpedparameter model that predicts hydrology and monthly nutrient loads, was applied to the Daugava River Basin, discharging into the Baltic Sea. The aim of the study was to model historic transport of nutrients into the Baltic Sea and thereby produce estimates of parameters and input data needed for a spatial extension of the GWLF to surrounding river basins.</p><p>Calibration data were taken from the 1990’s and validation data from the 1980’s. Yearly nitrogen loads were modelled with an R2 value of 0.78 for the calibration period. Predicted yearly nitrogen loads for the validation period were about 30 % lower than reported values, probably depending on decreasing groundwater and runoff concentrations between the 1980’s and 1990’s. Phosphorus loads were underestimated compared to reported values, the main reason probably being the exclusion of septic systems and too low reported point sources.</p><p>Modifications of the model are suggested for longterm predictions of nutrient loads and the need for harmonised, uptodate and generally accessible data for nutrient transport modelling discussed.</p>
4

Análise geomorfológica da bacia do ribeirão Balainho / Suzano - SP / Geomorphological analysis of Ribeirão Balainhos drainage basin / Suzano - SP

Flores, Diego Moraes 03 September 2012 (has links)
Esta pesquisa consistiu na análise geomorfológica e em um conjunto de levantamentos dos aspectos físicos da bacia hidrográfica do Ribeirão Balainho. O trabalho baseou-se no mapeamento morfométrico e morfográfico, além de observações de campo para o levantamento das características morfológicas da referida bacia. Os dados coletados visaram também estabelecer as características morfoestruturais e morfoesculturais, a fim de indicar áreas com maior potencialidade a processos denudativos. Para tal, optou-se pela utilização de cartografia geomorfológica de detalhe (1: 25.000) por meio da fotointerpretação de fotografias aéreas e de técnicas de mapeamento (morfografia) apresentadas por Tricart (1965) e Verstappen e Zuidam (1975). Quanto às técnicas na confecção das cartas morfométricas, estas se basearam nos apontamentos de Spiridonov (1981), Cunha, Mendes e Sanches (2003). As modificações morfológicas observadas, sobretudo os processos lineares de erosão foram associados a causas distintas em cada setor compartimentado da bacia (alta, média e baixa bacia), devido a características geológicas, morfológicas, pedológicas, de cobertura superficial e de usos distintos do solo. / This research is consisted of a set of data about the physical aspects of the Ribeirão Balainhos drainage basin. The study is based on morphometric and morphografic mapping and on field observations for the attainment of morphological characterization of the drainage basin. The data collected aimed to determine the morphostructural and morphosculpture characteristics, with the goal of point the areas with higher risks to suffer denudation process. For this, it was chosen the detailed geomorphological cartography (1:25.000), by the photointerpretation of aerial photographs and mapping technics (morphography), given by Tricart (1965) and Verstappen and Zuidam (1975). By the technics used in creation of the morphometrics charts, they were based on Spirodonov (1981), Cunha, Mendes and Sanches (2003) notes. The morphological changes viewed, especially the linear erosions processes, were associated to different reasons in each sector compartmented of the basin (upper, middle and lower), due the geological, morphological, pedological, surface coverage soil and land uses characteristics.
5

Defining Efficient Water Resource Management in the Weber Drainage Basin, Utah

Wilde, Keith D. 01 January 1976 (has links)
The Weber Basin Water Conservancy District is a state institution, but its primary function is collecting money for the U.S. Bureau of reclamation, to pay for the Weber Basin Project. Different classes of water users pay markedly different fees for identical Project services. More than half of the water developed by the Project is not used consumptively, yet supply facilities continue to be built in the Basin because they are less expensive to their owners than prices charged for the underused capacity of the Project. Paradoxically, some Basin residents are bitterly resentful to both the District and the Bureau, claiming that water rights formerly their own have, by means of the Project, been stolen. That is, both the enemies and the proponents of the Project adhere to the Western orthodoxy that water is scarce and drought imminent. The principal difficulty of this investigation lay in identifying the nature of the problem, for the situation seemed full of contradictions. Consequently, the primary contribution of the dissertation is an explanation of Basin circumstances that accounts for arresting observations without inconsistency or contradiction. The most important hypotheses are, therefore, empirical, or historical and institutional. Economics, according to Richard T. Ely and Frank H. Knight, is a set of principles concerning what ought to be, not empirical descriptions of what is. Consistent with that perspective, once the nature of the problem is clear, applications of economic principles is a prescriptive judgement of how the problem may be resolved. The most important empirical hypotheses are as follows: Water is not scarce in the Weber Basin; neither are storage and conveyance facilities. All are abundant, even redundant. Nevertheless in combination with certain institutional arrangements and sustained propaganda campaign, this very abundance contributes to persistence of the attitude that water is scarce. Redundant facilities thereby encourage even more unneeded development. What appears on first examination to be a case of misallocated water resources by discriminatory prices, turns out to be a problem of distributing the burden of paying for excessive, unwanted public works. Water itself is a free good in the Basin. Actual distribution of the repayment burden is partly ideological and partly pragmatic; partly a political choice and partly a bureaucratic decision; partly a manifestation of agrarian policy and partly what the traffic will bear. If water is free, it is not an economic good, and not a subject for economic analysis. The Basin has an ample water supply, but water may nevertheless be locally and periodically scarce. The water problem is therefore one of conveyance and timing. Control of timing requires storage. Conveyance requires energy, as well as aqueducts. In the Weber Basin, conveyance energy may be either the controlled flow of falling (mountain) water, or electrically powered pumps tapping abundant groundwater reservoirs. The water development problem is therefore, an issue of alternative capital facilities for the control and delivery of water (itself abundant). Efficient resource allocation in water development is consequently relevant at the investment level; it is not a matter of pricing water. In this case, the major investment decisions have already been implemented, and the problem is one of evaluating distribution of the repayment burden. The relevant economics literature is principles of equitable taxation, and of public utilities' pricing. Application to the basin situation produces a conclusion that present arrangements are as equitable as could be devised. Further redundant investment (inefficient use of resources), however, could be avoided if the State Engineer's Office took a harder line on requests to drill new wells. The information provided in this work could be the basis for making such a program popularly acceptable.
6

The Effects of High Density Septic Systems on Surface Water Quality in Gwinnett County, Georgia

Anderson, John R, II 15 December 2010 (has links)
Gwinnett County, Georgia experienced rapid growth in the 1970’s without the infrastructure so septic systems were installed for residential homes. The number of septic systems grew to over 85,000 with a density of 487 septic systems per square mile. This study mapped the distribution of septic systems to determine regions of potential pathogen surface water. This study addressed what potential health risks do high density septic systems have on surface water quality and how can the history of Gwinnett County assist in future development in the Metropolitan Atlanta area? It was found that the density of septic systems has reduced the surface water quality for streams in the Yellow and Alcovy River basins. An average rainfall cause septic flushing and an increase in the fecal coliform. Other trends observed in the surface water quality of increased BOD, water temperature, and various metals also indicated this flushing effect.
7

Análise geomorfológica da bacia do ribeirão Balainho / Suzano - SP / Geomorphological analysis of Ribeirão Balainhos drainage basin / Suzano - SP

Diego Moraes Flores 03 September 2012 (has links)
Esta pesquisa consistiu na análise geomorfológica e em um conjunto de levantamentos dos aspectos físicos da bacia hidrográfica do Ribeirão Balainho. O trabalho baseou-se no mapeamento morfométrico e morfográfico, além de observações de campo para o levantamento das características morfológicas da referida bacia. Os dados coletados visaram também estabelecer as características morfoestruturais e morfoesculturais, a fim de indicar áreas com maior potencialidade a processos denudativos. Para tal, optou-se pela utilização de cartografia geomorfológica de detalhe (1: 25.000) por meio da fotointerpretação de fotografias aéreas e de técnicas de mapeamento (morfografia) apresentadas por Tricart (1965) e Verstappen e Zuidam (1975). Quanto às técnicas na confecção das cartas morfométricas, estas se basearam nos apontamentos de Spiridonov (1981), Cunha, Mendes e Sanches (2003). As modificações morfológicas observadas, sobretudo os processos lineares de erosão foram associados a causas distintas em cada setor compartimentado da bacia (alta, média e baixa bacia), devido a características geológicas, morfológicas, pedológicas, de cobertura superficial e de usos distintos do solo. / This research is consisted of a set of data about the physical aspects of the Ribeirão Balainhos drainage basin. The study is based on morphometric and morphografic mapping and on field observations for the attainment of morphological characterization of the drainage basin. The data collected aimed to determine the morphostructural and morphosculpture characteristics, with the goal of point the areas with higher risks to suffer denudation process. For this, it was chosen the detailed geomorphological cartography (1:25.000), by the photointerpretation of aerial photographs and mapping technics (morphography), given by Tricart (1965) and Verstappen and Zuidam (1975). By the technics used in creation of the morphometrics charts, they were based on Spirodonov (1981), Cunha, Mendes and Sanches (2003) notes. The morphological changes viewed, especially the linear erosions processes, were associated to different reasons in each sector compartmented of the basin (upper, middle and lower), due the geological, morphological, pedological, surface coverage soil and land uses characteristics.
8

Solute pathways in a forested ecosystem : a drainage basin approach

Carter, A. D. January 1983 (has links)
The project sought to identify direct links between calculate hillslope solute fluxes and input/output budgets in a forested drainage basin in the United Kingdom. An intensive, short term monitoring and data collection programme was devised in order to quantify the major components for the hillslope hydrological cycle, the seasonal changes in overstorey and understorey biomass, and the chemical composition of ecologically and pedologically derived samples. Gross and net precipitation, infiltration, and soil moisture fluxes, groundwater movement and streamflow were monitored to identify the possible pathways which solutes might follow. Regular sampling of the oak and bracken vegetation, litterfall and litter enabled calculation of biomass accumulation and the rate of uptake and release of plant nutrients. The spatial variability of soil properties was quantified, but subsequent soil sampling permitted identification of seasonal trends in exchangeable action and soil water solute concentrations. All hydrological and ecological samples were analysed for nitrogen, phosphorus, potassium, calcium, magnesium, sodium and chloride. PH, specific conductance and organic carbon were measured for selected samples. The high infiltration capacity of the soil promoted rapid vertical movement of water towards a perched water table. The presence of soil macropores and the high permeability of the soil precluded the generation of throughflow on the hills-lope. Stream discharge was mainly controlled by groundwater fluxes from the perched water table. Although seasonal trends in the solute concentration of water samples and in the nutrient assimilation of vegetation were identified, isolated events, such as frassfall and storm-period litterfall, were shown to contribute significant quantities of nutrients to the forest floor, The importance of solute movement via macropores, especially phosphorus, was emphasised, with particular reference to plant availability. The relative stability of the ecosystem was reflected in the balance of the input/output budgets of solutes, with, the exception of calcium and magnesium losses which were attributable to weathering of the calcareous bedrock. Bivariate and multivariate statistical analysis showed that no single biogeochemical process on the hillslope could be identified as exerting a dominant controlling influence on stream water chenistry, through isolated events may affect concentrations in the short term.
9

Características hidrogeoquímicas da bacia de drenagem do rio Sorocaba, SP: processos erosivos mecânicos e químicos / Hydrogeochemical characteristics of the Sorocaba River basin drainage, SP: mechanical and chemical erosion processes

Fernandes, Alexandre Martins 08 August 2012 (has links)
A caracterização hidrogeoquímica da bacia do rio Sorocaba foi realizada a partir do estudo detalhado das cargas fluviais particulada e dissolvida, considerando a dinâmica dos transportes das principais espécies químicas, bem como os aportes atmosféricos e antrópicos, identificando os processos erosivos mecânicos e químicos predominantes na bacia de drenagem. A caracterização hidrológica permitiu identificar os principais mecanismos de recarga e descarga na bacia de drenagem e determinar o escoamento superficial rápido, revelando os períodos de maior potencial erosivo nos últimos 20 anos. O estudo da dinâmica da carga fluvial particulada mostrou a ocorrência de processos de remobilização e sedimentação ao longo da bacia, permitindo verificar um aumento do transporte fluvial específico em 2,5 vezes das nascentes até a foz. A erosão mecânica, calculada com base no transporte de sedimentos finos em suspensão junto à foz do rio Sorocaba, foi de 55,70 t km-2 a-1, indicando uma taxa de degradação física de 37,88 m Ma-1. A origem da matéria orgânica na carga particulada fluvial se mostrou associada aos efluentes domésticos após caracterização isotópica do 13C. O comportamento hidroquímico fluvial evidenciou uma diferença de predomínio de espécies químicas dissolvidas entre as cinco estações de amostragem, permitindo verificar a influência dos processos de diluição fluvial, de acordo com as relações concentração x vazão. O modelo geoquímico utilizado permitiu estimar o CO2 atmosférico/solo consumido durante o processo de alteração de rochas na bacia de drenagem em 198 x 103 moles km-2 a-1, dos quais 98% foi relacionado à alteração de silicatos. O modelo de reconstituição desse consumo nos últimos 59 anos mostrou-se pouco variável, entretanto o modelo associado exclusivamente aos silicatos indicou um aumento no mesmo período, a uma taxa de 2,7 x103 moles km-2 a-1. Comparada com a erosão mecânica, a erosão química se mostrou inferior em cerca de 2,5 vezes, enquanto que, ainda em termos de erosão química, as taxas de alteração de silicatos e carbonatos na bacia de drenagem foram de 9,4 e 5,3 m Ma-1, respectivamente. O índice de alteração de rocha RE, determinado a partir dos dados geoquímicos das águas fluviais, indicou a mudança de um possível domínio de estabilidade da caulinita para o das argilas 2:1, evidenciando a ocorrência do processo de bisialitização / The hydrogeochemical characterization of the Sorocaba River basin was performed from the detailed study of particulate and dissolved river loads. Considering the main chemical species transported, as well as the atmospheric and anthropogenic inputs, it ws identified the mechanical and chemical erosion processes prevailing in the drainage basin. The hydrologic characterization identified the main mechanisms of recharge and discharge in the drainage basin, and allowed to determine the quickly surface runoff, showing periods of increased erosion potential in the last 20 years. The study of the particulate load dynamics demonstrated the occurrence of sedimentation and remobilization processes in the basin, allowing to verify a specific fluvial transport increased by 2.5 times from headwaters to the mouth of the Sorocaba River. The mechanical erosion, calculated based on the fine suspended sediments transported at the mouth of the Sorocaba River, was 55.70 t km-2 yr-1, indicating a physical degradation rate of 37.88 m Myr-1. The origin of organic matter present in the particulate load was associated to domestic sewage, after isotopic characterization of the 13C. The fluvial hydrochemical performance revealed the predominance of different dissolved chemical species between the five sampling stations, enabling to verify the influence of fluvial dilution processes, according to the concentration-discharge relationships. The geochemical model used allowed us to estimate CO2 atmospheric / soil consumed during the alteration rocks process in the drainage basin of 198 x 103 mol-1 km2 yr-1, which 98% was related to silicates alteration. The reconstitution model of this consumption in the last 59 years has shown to be little variable, however the model exclusively associated with silicates demonstrated an increase during same period, in a rate of 2.7 x 103 moles km-2 yr-1. Compared to mechanical erosion, the chemical erosion was inferior to about 2.5 times, whereas, also in terms of chemical erosion, the silicate and carbonate alterations rates in the drainage basin were 9.4 and 5.3 m Myr-1, respectively. The rock alteration index RE, determined from the geochemical data, indicated a possible change in the kaolinite stability domain to the clays 2:1, indicating the occurrence of the bisialitization process
10

Interações pedogeomorfológicas em bacia de drenagem no semiárido baiano / Soil-geomorphology interactions in drainage basin in the semi-arid Bahia

Jucelia Macedo Pacheco 04 May 2018 (has links)
Este trabalho faz parte do processo de investigação e conhecimento da evolução da paisagem a partir da interação solo-relevo, isto é, de uma abordagem pedogeomorfológica. Como tais estudos são escassos no semiárido brasileiro e, considerando o interesse em contribuir com o conhecimento e disseminação da geo e biodiversidade deste domínio, foi selecionada para estudo uma área localizada no setor nordeste do estado da Bahia, próxima ao município de Nova Soure. O recorte espacial adotado foi a bacia de drenagem, por entender que a bacia é, mesmo em condições semiáridas, uma unidade importante para a compreensão das relações entre formas e materiais, como a cobertura pedológica. A bacia selecionada é a do Riacho Natuba, que está, geologicamente, localizada na bacia sedimentar do Tucano Sul, que integra o rifte Recôncavo-Tucano-Jatobá. Geomorfologicamente está inserida nos Tabuleiros do Itapicuru, formados por modelados de aplainamentos e dissecação. O estudo foi realizado a partir de etapas de gabinete, campo e laboratório, que incluíram: revisão bibliográfica e conceitual, levantamento de materiais cartográficos, processamento de imagens e produção de mapas através do geoprocessamento, trabalhos de campo com reconhecimento da área, descrição e coleta de perfis de solos, análises laboratoriais e estudos microscópicos de seções delgadas. Diferentes escalas foram adotadas para o estudo da relação solo-relevo. Na escala da bacia, o estudo foi realizado a partir da identificação e descrição dos compartimentos morfopedológicos. Na escala da vertente, o estudo foi realizado a partir da descrição e caracterização de solos ao longo de transectos entre os compartimentos morfopedológicos e na escala de detalhe foram observadas as microestruturas em lâminas com o auxílio de microscópios petrográficos. Os resultados indicaram que a bacia é pedodiversa e que essa variedade e distribuição de solos possui íntima relação com a variação de litofácies da Formação Marizal e com processos do relevo, como a erosão seletiva superficial e subsuperficial de finos (argilas). Os solos de maior ocorrência nas partes altas da bacia são os Neossolos Quartzarênicos, que se diferenciam pelo conteúdo de argila, composição mineralógica e arranjos do fundo matricial. Essas distinções foram interpretadas como produtos da influência da circulação da água, atestando a importância do relevo na sua gênese. Nas partes baixas da bacia, a diversidade de solos é maior, ocorrendo Argissolos, Luvissolos, Chernossolos, Neossolos Fluvicos e Planossolos. Todos refletem propriedades dos materiais de origem sob condições de intemperismo típicas do semiárido, como a fertilidade, a mineralogia e as organizações micromorfológicas. Além disso, também estão relacionados aos processos erosivos atuantes nas vertentes, que formam, por exemplo, o gradiente textural, seja através da elutriação (Argissolos e Luvissolos) ou através da sedimentação (Planossolos). De maneira geral, os solos da bacia estão interligados entre si, e essa ligação se dá a partir da redistribuição de material ao longo das dinâmicas do relevo. Este contexto expressa a importância de considerar conjuntamente a pedogênese e morfogênese na evolução da paisagem semiárida. / This work is part of the process of research and knowledge of the evolution of the landscape from the interaction between soil and relief, i.e., a soil geomorphological approach. Aiming to contribute to and disseminate the knowledge of the geo- and biodiversity of the Brazilian semiarid, where studies such as this one is rare, we investigated an area in the northeast of Bahia, near the Nova Soure municipality. The drainage basin was picked as the unit of spatial analysis because, even in semiarid conditions, we understand it to provide the best comprehension of the relationships between shapes and materials, such as soil coverage. The Natuba stream drainage basin we investigate in this study is geologically situated in the Tucano Sul sedimentary basin, itself part of the Recôncavo-Tucano-Jatobá rift. Geomorphologically, the basin is part of the Itapicuro tablelands, formed by surfaces of planation and dissection. The investigation involved office, field, and laboratory stages, including: literature and conceptual review, gathering of cartographic material, image processing, geoprocessing to produce maps, area survey and fieldwork, profile description and sampling, laboratory analysis, and thin section microscopy. We adopted different scales to study the soil-relief relationship. At the basin-scale, the study comprised the identification and description of morphopedological compartments. At the slope-scale, the study was derived from the description and characterization of soils along transects between morphopedological compartments. Finally, at the detail-scale we observed the microstructures on slides, using petrographic microscopes. Results indicate that the basin is soil-diverse and that its variety and distribution is intimately related to the variation of the lithofacies of the Marizal Formation and to relief processes such as superficial and subsuperficial erosion of fine material (clays). The Quartzarenic Neosols, more frequent in the higher regions of the basin, are differentiated by the clay content, mineral composition, and the relative distribution of groundmass. These distinctions were interpreted as products of the influence of water circulation, substantiating the importance of the relief in the soil genesis. At the lower regions of the basin, the soil is more diverse: Acrisols, Luvisols, Chernozems, Fluvisols, and Planosols occur. Fertility, mineralogy and micromorphological organization of the soils are typical of the original material enduring conditions of weathering that are characteristic of the semiarid. Furthermore, the soils are related to the erosive processes that affect the slopes and form, for instance, the textural gradient as a result of elutriation (Acrisols and Luvisols) or sedimentation (Planosols). Generally, the basin soils are interlinked via the redistribution of material throughout the landscape. This context, therefore, expresses the importance of considering both pedogenesis and morphogenesis when examining the evolution of the semiarid landscape.

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