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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.
11

Pedoambientes e aspectos hidrológicos como base para gestão territorial do município de Xapuri, Acre / Pedoenvironment and hydrological aspects as a basis for land management in the municipality of Xapuri, Acre

Abud, éllen Albuquerque 24 February 2011 (has links)
Made available in DSpace on 2015-03-26T13:53:27Z (GMT). No. of bitstreams: 1 texto completo.pdf: 5607440 bytes, checksum: 81cf06c45dc5dc66a5b6e2738761adb7 (MD5) Previous issue date: 2011-02-24 / Xapuri County, founded on March 22nd 1904, its situated on a 5.346 km2 area, is located on a higher region of Acre, and it is considered the birthplace for The Amazon s environmental fight, due to the conflicts and land exploitation, in order to control the land, led by the union leader Francisco Alves Mendes Filho, internationally known as Chico Mendes. Currently, Xapuri County has been dealing with a difficult challenge in searching for alternatives for its soil s use that would enable the deforested areas to have a sustainable development, as well as to better exploit the Forest s area, for the environmental capability and susceptibility and to fully incorporate the locals knowledge. Therefore, it is necessary to have socio-environmental knowledge, in order to distinguish the current employ of the County s land, as well as to better understand its natural resources on the same level as the existing cartographic equipment, teamwork that would allow preserving the environment and executing such contemporary development to exert and work the county s land. The aimed is to present alternative settings of reasonable and sustainable application of the land, with premises on current land application, along with knowledge of natural resources, specially soil and hydrographic characteristics, in order to distinguish Soil-forming environment factors, to form a foundation for the County s projection. Thus, a soil recognition research was conducted, and from such inquiries, a geological and ridge map was formulated, as well as the land s exertion by SRTM and LANDSAT satellite images, minding the preservation of Soil-forming environment factors. Consequently, to correlate Soil-forming environment factors with classes of land exertion and obtain appropriate zoning of land exertion and zoning of the Hydrographic factors on soil, on a 1:100.00 scale. Thus, the County can be divided into four Soil-forming environment. It was noticed a predominance of Clay soils, with strong influence from the source materials and clay migration, as well as not so weathered Oxisols soils. The land application s adequacy showed class predominance: lack of substantial impact (39%), as consequence of the largest preserved forest area (77%). However, results showed low to high impact on the application concentration outside of the preserved area. According with the zoning of the Hydrographic factors on soil, it was possible to observe Xapuri County in a territorial management perspective as a whole, as a result, with grounds on these studies, concluding considerable change in Areas of permanent preservation. / O município de Xapuri, criado em 22 de março de 1904, apresenta uma superfície de 5.346 km2 e localiza-se na regional do Alto Acre e é considerado o berço da luta ambiental da Amazônia em razão dos conflitos e exploração da terra liderados pelo sindicalista Francisco Alves Mendes Filho conhecido internacionalmente como Chico Mendes. Atualmente, o município tem enfrentado um grande desafio na busca de alternativas de uso da terra que possibilitem alcançar o desenvolvimento sustentável nas áreas desmatadas e valorização do uso múltiplo da floresta, pelo reconhecimento das potencialidades e vulnerabilidades ambientais e com a incorporação efetiva da sabedoria local. Diante disso, se faz necessário o conhecimento dos aspectos sócioambientais, de modo a caracterizar o uso atual das terras do município, além de conhecer melhor seus recursos naturais em escala compatível com os materiais cartográficos existentes, equipe de trabalho que possibilite estratificar o ambiente e realizar um planejamento de uso e ocupação das terras mais realísticos para a região. Objetivou-se propor cenários de uso racional e sustentável da terra com base nas relações de uso atual com o conhecimento dos recursos naturais, principalmente características pedológicas e hidrográficas de modo a distinguir os pedoambientes, para se constituir uma base de planejamento para o município. Para tanto, realizou-se o levantamento de reconhecimento de solos e a partir dessas informações elaboraram-se o mapa de geologia e relevo, além do uso da terra com imagens SRTM e LANDSAT com vista a estratificação dos pedoambientes. Para assim relacionar os pedoambientes com as classes de uso da terra e obter o zoneamento adequado do uso da terra e o zoneamanto pedo-hidrográfico, em escala de 1:100.000. Assim, pode-se dividir o município em quatro pedoambientes. Onde se observou o predomínio dos Argissolos, com influência marcante do material de origem e migração de argila, e Latossolos não tão intemperizados. A adequação do uso apresentou predominância da classe: ausência de impacto significativo (39%), em decorrência da grande área de floresta preservada (77%). Mas apresentou fora da área preservada intensidade de uso com baixo a alto impacto. De acordo com o zoneamento pedo-hidrográfico foi possível visualizar o município num contexto de gestão territorial integrada e através desta análise constatar considerável alteração nas Áreas de Preservação Permanentes.
12

Analysis and synthesis of data on relationships between soil factors and soil erosion in South Africa

Mulibana, Nthanyiseni Elvis 10 October 2005 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MInst Agrar (Land-Use Planning))--University of Pretoria, 2006. / Agricultural Economics, Extension and Rural Development / unrestricted
13

SPECTRAL PROPERTIES OF ARIZONA SOILS AND RANGELANDS AND THEIR RELATIONSHIP TO LANDSAT DIGITAL DATA

Horvath, Emilio Hubert January 1981 (has links)
The relationships between the spectral properties of Arizona soils and rangelands and their characteristics were studied. The per cent reflectance of soils was determined using a multispectral hand-held radiometer, and the spectral response of Arizona rangeland sites was measured by scanners aboard an orbiting satellite. These spectral properties were related, by means of stepwise multiple regressions, to various soil and site characteristics. This research is presented in three chapters. The first chapter describes the relationships between soil properties and their spectral reflectance as determined in a laboratory environment. The second chapter attempts to correlate spectral properties of soils measured with a radiometer and that measured by scanners aboard an orbiting satellite for a small area near Winkelman, Arizona. The third chapter describes the relationships between the properties of 243 rangeland sites in central and southeastern Arizona and Landsat spectral data values. Determinations of Munsell soil colors and the radiometrically measured reflectance of 163 soils led to the development of charts for converting Munsell color to reflectance. Little difference was found between Munsell color measured in the sun and that measured indoors, and on the average, soil scientists were in agreement 80 per cent of the time. Munsell value, organic carbon, carbonates, and Munsell chroma explained 80 per cent of the variability within the reflectance measurements of these soils. The spectral response of the less than 2 mm soil fraction collected from rangeland surfaces was significantly different from the spectral response of coarser fragments collected from the same surface. In the Winkelman area the radiometrically measured reflectance of the less than 2 mm fraction alone accounted for 46 per cent of the variability and the reflectance of the 13 to 76 mm fraction accounted for 17 per cent of the variability within the satellite measured response. This area had a low vegetative cover and soil-geologic features, particularly soil color, correlated best with the Landsat digital data. Seventy-six per cent of the satellite data were explained by the interaction of the per cent coarse fragments times its reflectance, the average slope of the sites and the per cent soil less than 2 mm fraction times its reflectance. The relationship between the properties of 110 rangeland sites in central Arizona and the sum of the four Landsat spectral bands was determined. The sum of brush and forest crown densities, elevation, soil color,Geology of the site, and the per cent of surface covered with cobbles explained 82 per cent of this variation. An evaluation of field measurements only to explain the variability among mapping units showed the sum of brush and forest crown densities, elevation, clay content, and fragments greater than 2 mm explained 67 per cent of this variation. When satellite data were added to the field measurement site characteristics, the ratio of satellite scanner bands 4+5 to 6+7 becomes the most significant factor in explaining the variation among mapping unit symbols and a greater per cent of the variability could be explained. A similar study conducted on 133 sites in southeastern Arizona gave different results as only 41 per cent of the variability could be explained. It was shown that for central and southern Arizona rangelands, it is possible to define specific relationships between site characteristics and satellite measured spectral response. Less than ten site characteristics and their interactions explain considerable portions of the variability between mapping units for a given survey. These relationships are unique for specific locations, but they could easily be developed for a survey area and effectively used in the mapping process.
14

Análise das características do solo de Francisco Beltrão - PR e suas influências nas inundações do perímetro urbano / Analysis of the soil characteristics of Francisco Beltrão-PR and its influence on the flooding of the urban perimeter

Minuzzo, Simone 30 November 2016 (has links)
A ocupação territorial do município de Francisco Beltrão foi realizada pensando apenas nas necessidades emergenciais, sem pensar na degradação que esta ocupação sem o planejamento adequado transferiria ao meio ambiente e aos seus habitantes. O processo de urbanização intenso impermeabilizou massivamente o solo, assoreou os rios e removeu grande parte da mata ciliar, fatores estes que fazem elevar a vulnerabilidade em relação às inundações. O objetivo deste trabalho foi fazer a espacialização dos resultados de ensaios de caracterização de 24 amostras de solo em mapas temáticos, bem como fazer mapas temáticos para caracterizar o relevo e o uso e ocupação do solo. O SIG utilizado foi o SPRING. Para análise dos resultados foram realizados diversas tabulações cruzadas entre os mapas. A classificação do solo foi realizada de acordo com a Classificação Unificada e com a textura. Determinou-se a infiltração do solo em diversos pontos através do método de anéis concêntricos. A densidade do solo, em geral, se mostrou mais preponderante nas interferências na taxa de infiltração que a textura do solo. Através do mapa de uso e ocupação de solo verificou-se a elevada impermeabilização do território e a falta de áreas verdes para amortecimento da águas de chuva, assim como a escassez de mata ciliar. Através do cruzamento de informações entre o mapa de uso e ocupação do solo com o mapa de hipsometria constatou-se que uma área construída correspondente a 18,75% da área urbana encontra-se em local de risco de inundação. Quatro mapas de manchas de inundação foram obtidos através do reconhecimento do alcance das manchas de inundação dos períodos de 2011, 2013, 2014 e 2015. De acordo com os levantamentos realizados a cota máxima de inundação determinada foi de 548m. Foi realizada a tabulação cruzada entre o mapa de declividade com os mapas de mancha de inundação que demonstram que as áreas mais afetadas pelas inundações são as de menor declividade (0 a 3%) que totalizam 53,58% das áreas inundadas. Os mapas temáticos gerados fornecem informações importantes sobre as características do território urbano. Os resultados apresentados podem auxiliar no planejamento e readequação do espaço urbano. / Land occupation in Francisco Beltrão, Paraná, was carried out bearing in mind only emergency needs, without considering the impact this unplanned occupation would have on the environment and on its inhabitants. The intense urbanization process waterproofed the soil, silted the rivers and removed the riparian forests, factors that increase vulnerability to flooding. The objective of this paper has been to spatialize the results of characterization tests of 24 soil samples in thematic maps, as well as making thematic maps to characterize the relief and the use and occupation of the soil, as well as maps with the floods that occurred in 2012, 2013, 2014 and 2015. The GIS - Geographic Information System used was SPRING. In order to analyze the results, there have been several cross-checks of data between the maps. Soil classification was performed according to the Unified Classification and with the texture. Soil infiltration at 23 points was determined by the concentric ring method. Soil density, in general, showed to be more preponderant in the interferences in the infiltration rate than the soil texture. The land use and occupation map showed the high waterproofing condition of the territory and the lack of green areas to cushion the rainwater, as well as the scarcity of ciliary forest. Through the cross-linking of the map of land use and occupation with the map of hypsometry, it was verified that a constructed area corresponding to 18.75% of the urban area is located at a risk of flood area. Four maps of flood spots were obtained by recognizing the extent of flood spots in the periods of 2011, 2013, 2014 and 2015. According to the surveys, the maximum flood level determined was 548m. Crossing between the declivity map and the floodplain maps shows that the areas most affected by the floods are those with the lowest slope (0 to 3%), which total 53.58% of the flooded areas. The resulting thematic maps provide important information about the characteristics of the urban territory. The presented results can help in the planning and re-adaptation of the urban space.
15

Atributos físicos e micromorfológicos da estrutura de um Latossolo Vermelho distroférrico típico submetido ao manejo agrícola / Physical and micromorphological attributes of the structure of a Rhodic Hapludox under agricultural management

Silva, Laura Fernanda Simões da 19 August 2018 (has links)
Orientadores: Mara de Andrade Marinho, Edson Eiji Matsura / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-19T11:10:54Z (GMT). No. of bitstreams: 1 Silva_LauraFernandaSimoesda_D.pdf: 13977443 bytes, checksum: 9d8e76e6eed7bedacb43c17037906997 (MD5) Previous issue date: 2011 / Resumo: A estrutura é um dos atributos mais importantes do solo sob o ponto de vista agrícola, sendo não somente influenciada pelo clima, atividade biológica e práticas de manejo, mas também por forças de natureza mecânica e físico-química. Nesse contexto, o trabalho teve por objetivo geral avaliar a influência do uso e do manejo agrícola sobre a qualidade estrutural de um LATOSSOLO VERMELHO Distroférrico típico (Rhodic Hapludox). A avaliação foi realizada com base em indicadores físicos tradicionais e empregando técnicas de análise micromorfológica e micromorfométrica. A pesquisa foi desenvolvida em Campinas, SP, em duas parcelas experimentais cultivadas com milho, uma sob Sistema Plantio Direto (SPD) e outra sob Sistema Convencional (SC)... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Soil structure is one of its most important attribute concerning the agricultural point of view, being influenced not only by climate, biological activity and management practices, but also by mechanical and physical- chemical forces acting in it. In this context, the main purpose of this work was to evaluate the influence of agricultural use and management on the structural quality of a Rhodic Hapludox. The evaluation was carried out considering traditional physical indicators and also by employing micromorphological and micromorphometrical techniques. The study was developed at Campinas, SP, in an experimental area with maize under no-till system (NT) and conventional system (CS)¿ Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Agua e Solo / Doutor em Engenharia Agrícola
16

An integrated approach for the delineation of arable land and its cropping suitability under variable soil and climatic conditions in the Nkonkobe municipality, Eastern Cape, South Africa

Manyevere, Alen January 2014 (has links)
Arable crop production in Nkonkobe Municipality is low due to abandonment of potentially productive land and low productivity of the cultivated land. Little attention has been given to farmers perspectives with regards to crop production and land abandonment. Understanding the relationships of indigenous knowledge systems, where local approaches to soil classification, appraisal, use and management and land evaluation, and scientific approaches could be important for the effective use of available soil resources while avoiding those resources that are vulnerable to degradation. In addition, the interactions between soil factors and climate could be useful in understanding the erodibility of soils. The intergration of scientific research and indigenous knowledge systems could help in the identification and delineation of high potential land and on crop suitability evaluation. The objectives of the study were: (i) to determine farmers‟ perspectives with regards to land utilisation and abandonment, constraints on crop production and crop preferences, (ii) to integrate and compare indigenous knowledge systems with scientific approaches of soil classification and potential, (iii) to determine the effect of climate and soil factors on erodibilities of soils in the Municipality (iv) to delineate arable land and evaluate its suitability for maize, potato, sorghum and cowpea under rainfed agriculture. Using semi-structured and open-ended interviews, information on limitations to crop production, cropping preferences, indigenous soil classifications, cropping potential ratings and erosion was captured. Descriptive and correlation statistics were used to analyse farmers‟ responses. The information was later used for a pilot participatory mapping and the determination of the agricultural potential of the soils in three selected villages of the Municipality. Field boundaries of soil texture, colour, depth, and slope position were captured using global positioning systems (GPS). The relationship between the degree of erosion and soil and slope factors was analysed by step-wise regression. Crop suitability for rainfed agriculture was done using the FAO guidelines for Land evaluation for rainfed agriculture. The spatially referenced crop suitability classes were produced by applying the Law of Limiting Combinationusing GIS Boolean Logic. The major biophysical factors, affecting crop production and land utilisation were soil degradation and low and erratic rainfall, while other factors included lack of farming equipment and security concerns. Maize, spinach and cabbage were the main crops grown, with maize sorghum and wheat the most abandoned crops. While it was difficult to accurately correlate indigenous classification with international scientific classification, the importance of colour, texture and soil depth for both classification and soil potential, suggests that some form of correlation is possible which enabled communication and other extension information to be conveyed. The shallow and stony soil (urhete) correlated well with the Leptosols in World Reference Base (WRB) or Mispah and shallow Glenrosa soils in the South African system. The red structured clays (umhlaba obomvu) matched the Nitisols in WRB or Shortlands in the South African system. The non-swelling black clayey soils (umhlaba omnyama) matched soils with melanic A horizons in both the WRB and South African soil classification systems. The dongwe and santi soils developed in alluvial sediments belonged to the Dundee, Oakleaf or Augrabies soils in the South African classification system and fluvisols or Cambisols in the WRB system. There was good agreement between farmers assessment of the cropping potential and scientific approaches but scientifically high potential red soils were rated lowly by the farmers due to difficulties in management caused by shortages of farm machinery, especially under dryland farming. Overall, the soil factors affecting erosion were influenced largely by climate, while parent material was also important. Climate had a dominant influence on soil factors most notably fine sand and very fine sand fractions and exchangeable sodium percentage being more important on soil forms occurring in arid and semi-arid climate and less in the sub-humid and humid areas, where clay mineralogy, particularly kaolinite and sesquioxide dominated. Dolerite derived soils were the most stable and should be given the highest priority for cropping development while mudstone and shale derived soils had a lower cropping potential. While slope gradient and length had some effect on soil erosion in arid and semi arid environments its influence was generally overshadowed by soil factors especially in humid zones. Cow pea and sorghum were the most adapted crops in the region while potato and maize were marginally suitable under rainfed agriculture. The study revealed that most adapted crops were not necessarily the most preferred crops by the farmers. A small percentage of the land was delineated as arable and therefore optimisation of this available land should be prioritized.
17

Evaluation and mapping of the spatial variability of soil fertility at Zanyokwe Irrigation Scheme in the Eastern Cape, South Africa

Manyevere, Alen January 2010 (has links)
No description available.
18

Melanic soils in South Africa : compositional characteristics and parameters that govern their formation

Van der Merwe, Gertruida Magaretha Elizabeth 06 December 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc (Soil Science))--University of Pretoria, 2006. / Plant Production and Soil Science / unrestricted
19

Análise jurídica e territorial do desmatamento na região de Pato Branco, Paraná / Legal and territorial do analysis of deforestation in the region of Pato Branco, Paraná

Zucchi, Paola Andriguetti 29 March 2018 (has links)
Há muito que a humanidade sabe que os recursos são finitos. Porém, nem sempre o desenvolvimento almejado por uma determinada sociedade estabelecida em determinado território é condizente com a disponibilidade dos recursos naturais, refletindo diretamente na qualidade do solo e instalando um desenvolvimento “insustentável”. Nesse cenário, a pesquisa objetivou analisar o desmatamento utilizando como ponto de partida autos de infração ambiental e características pedológicas do solo na Região de Pato Branco, Paraná. Os resultados foram obtidos por meio da análise de diversos conceitos em diferentes disciplinas e, também, pela utilização de geotecnologias na elaboração de mapas temáticos. Foram observadas cinco zonas de pressão ambiental, nas quais a classe de solo que possui maior incidência no desmatamento é também a classe de solo que abriga a atividade predominante. Outrossim, verificou-se que o desmatamento ocorre em solos mais sensíveis e propensos à erosão, como resultado histórico da colonização, que primeiramente ocupou os solos com maior capacidade de produção. A longo prazo, a solução será sempre a educação ambiental e a erradicação das desigualdades sociais e econômicas. Mas a curto prazo, no quesito meio ambiente, o fortalecimento da política pública ambiental representa uma alternativa de resposta à crise. / Humanity has long known that resources are finite. However, not always the development desired by a certain society established in a given territory is consistent with the availability of natural resources, reflecting directly on the quality of the soil and installing an "unsustainable" development. In this scenario, the objective of this research was to analyze deforestation using as a starting point cases of environmental infraction and pedological characteristics in the Pato Branco Region, Paraná. The results were obtained through the analysis of several concepts in different disciplines and also by the use of geotechnologies in the elaboration of thematic maps. Five zones of environmental pressure were observed, in which the class of soil that has the highest incidence of deforestation is also the class of soil that houses the predominant activity. In addition, deforestation occurred in more sensitive and erosion-prone soils, as a historical result of colonization, which first occupied soils with higher production capacity. In the long run, the solution will always be environmental education and the eradication of social and economic inequalities. But in the short term, in the environmental issue, the strengthening of public environmental policy represents an alternative response to the crisis.
20

Tillage, soil texture and mineralogy effects on selected soil properties on four soil types in Limpopo Province, South Africa

Magagula, Siyabonga Isaac 21 June 2020 (has links)
MSCAGR (Soil Science) / Department of Soil Science / The effects of tillage on soil structure and associated soil properties such as soil respiration may differ in different soils. The study determined the effects of tillage, soil texture and mineralogy in selected soil properties on different soil types. Soil samples were collected from four different sites in the Limpopo province, South Africa. The soils were classified as Glenrosa with sandy loam texture, Dundee with loamy sand, Hutton with clay, and Shortlands with clay. Glenrosa and Dundee were dominated by quartz, while Hutton and Shortlands with kaolinite. Soil samples were taken from the surface 0 – 20 cm under conventional tillage and no-till land. Soil organic matter, texture, and mineralogy were determined. The soils were wetted to activate the microorganisms and incubated for 70 days at 30℃ and soil respiration was determined using alkali trap method on a weekly basis. The study was conducted in triplicates and arranged in a completely randomized design. Data was subjected to analysis of variance using general linear model procedure of Minitab version 19. Means were compared using paired t-test at (p ≤ 0.05). The Pearson correlation coefficient (r) was used to measure the strength of linear dependence between variables. There was a significant difference in soil organic matter (p≤0.000) among all studied soils. The mean values of soil organic matter were 2.19% in Hutton, 2.0% in Shortlands, 0.54% in Glenrosa, and 0.43% in Dundee. Quartz had a strong negative linear relationship (r = -0.66) with soil organic matter while kaolinite had a strong positive linear relationship (r = 0.96). Soil respiration increased in soils dominated with quartz and decreased in soils dominated with kaolinite. The soil respiration increased by 18.95 g CO2 m-2 d-1 in conventional tillage and decreased by 13.88 g CO2 m-2 d-1 in no-tillage due to increased exposure of soil organic matter under conventional. It was concluded that less intensive tillage such as no-tillage reduces soil respiration. / NRF

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