Dissertations / Theses: 'Soil maps'

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Reed, Seann Mischa. "Use of digital soil maps in a rainfall-runoff model /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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Kraft, Jason Edmund. "Development of liquefaction susceptibility and hazard maps for the islands of Jamaica and Trinidad." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47676.

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Caribbean nations lie within a zone of distinct seismic hazard. While ground motion in the region has been analyzed, the potential for liquefaction has not been evaluated in most cases. In order to evaluate liquefaction, data describing soil composition, surficial geology, and seismic hazard analyses were collected and applied. This allowed for expansion of previously localized liquefaction analysis to be expanded to the extents of two island nations in the Caribbean. This thesis utilizes the Youd and Perkins (1978) qualitative liquefaction susceptibility and Holzer et al. (2011) liquefaction probability methodologies to evaluate the possibility of liquefaction in Trinidad and Jamaica during major seismic events. Maps were developed using geographic information system (GIS) data to compare susceptibility and hazard across the islands at varying levels of magnitude. In this way, the distribution of liquefiable deposits is displayed in a manner that can be used quickly and easily to motivate further study of susceptible regions and mitigation activities to reduce the risk posed by liquefaction in the countries.

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Eldridge, Simon Michael, and n/a. "The impact of the scale of mapping on soil map quality." University of Canberra. Resource, Environmental & Heritage Sciences, 1997. http://erl.canberra.edu.au./public/adt-AUC20060707.102807.

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It is generally assumed that increased map precision (ie map unit homogeneity) and map purity (map unit accuracy) should result from increasing the scale of mapping of the soil resource, since it should enable a more intricate breakdown of the landscape into landform facet based units. This study compared the predictive success of a 1:1 OK scale soil association map with the 1:25K and 1:1OOK scale soil landscape maps within the Birrigai area of the Paddy's river catchment, south west of Canberra, A.C.T. The 1:25K and the 1:100K scale soil landscape maps were also evaluated in a second larger evaluation area in the Paddy's river catchment which allowed more of the larger soil landscape map units to be evaluated. The 1:25K scale soil map was produced by another author for the A.C.T Government, and was surveyed at a substantially lower survey intensity than that for the 1:100K and 1:10K scale soil maps (ie only 0.05 observation sites / cm2 of published map). These maps were evaluated using a set of randomly located independent evaluation sites in each evaluation area, and from these calculating and comparing standard Marsman & de Gruijter(1986) measures of Map Purity. The strength of soil-landscape relationships within this catchment were determined from a Fixed One Way Analysis of Variance, and from more simplistic graphical comparisons of the means and standard deviations of the discrete soil data within these landform based map units. Soil-landscape relationships for the Nominal scale soil data (ie class type data) were evaluated by comparing the Marsman & de Gruijter(1986) Homogeneity index ratings among the soil map units. Intensive survey traverses were also carried out in selected soil landscapes to further evaluate the strength of soil landscapes present. The results revealed obvious improvements in map quality associated with increasing map scale from 1:100,000 to 1:10,000, and these included increases in the predictive success (Map Purity), reductions in the extent of map unit impurities, and planning advantages associated with having individual land facets delineated on the 1:10,000 scale map. The respectable purity ratings achieved by the 1:100,000 scale soil landscape map (ie average purity rating of 63%) was largely attributed to the flexibility of the "soil material" approach to soil landscape mapping. The relatively poor performance of the 1:25K consultancy soil landscape map demonstrated the fact that; any benefit gained from the improved intricacy in the representation of map unit delineation's with increased mapping scale, will be drastically reduced if it is not matched by an associated increase in the intensity of field investigations. Evaluations of the soil-landscape relationships found that the land facets of the Paddy's river catchment generally failed to delineate areas that were both uniform and unique in respect of their soil properties. Soil-landscape relationships were instead found to be quite complex, applying to only certain land facets, and in regards to only certain soil properties. Soil maps with units based on landsurface features were recommended on the basis of the importance of other landscape factors other than soils to land capability ratings, as well as on the useability of such maps. This study recommended the adoption of a " >2 detailed soil profile observations / land facet in each map unit " mapping standard to ensure a reasonable estimate of the variability and modal soil conditions present, as well as a reliable confirmation of the perceived soil-landscape relationships. The error usually associated with small scale mapping was effectively reduced by rapid ground truthing, involving driving along the major roads dissecting the map area and making brief observations of soil exposures on road batters, despite the bias of the road network making such mapping improvements uneven across the map. The major point to come from this study was the re-emphasising of the point that soil spatial variability has to be accepted as a "real landscape attribute" which needs to be accurately described and communicated to land users, and must not be considered as some sort of soil mapping failure. The fact that individual facets of the landscape rarely coincide with unique pockets of uniform and unique soils and soil properties must be considered simply an on the ground reality of nature, and not some mapping failure. It was thought that since other landscape factors (eg hillslope gradient) most often dominate the determination of land use suitability and capability, it is better to effectively describe the range and modal state of the soil conditions within such facets, then to attempt to extrapolate possible soil boundaries using geostatistical techniques which cut across such land facets, and may or may not correlate with real groupings of soil properties, depending on the spatial resolution of the soil variability distribution in the landscape. Even so the results of this investigation do put the validity of the physiographic terrain class mapping model as a predictor of soil traits under question, at least for the more complex landscape settings.

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Guan, Zhi Wei 1953. "Soil moisture approximation using thermal inertia maps : verification study on the relationship between HCMM observations and antecedent precipitation index for St. Lawrence Lowland of Southern Quebec." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55601.

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Lowman, Amelia M. "Creation of soil liquefaction susceptibility maps for San Luis Obispo & Marin counties using geographic information systems /." Click here to view, 2009. http://digitalcommons.calpoly.edu/erscsp/2.

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Thesis (B.S.)--California Polytechnic State University, 2009.
Project advisor: Lynn E. Moody. Title from PDF title page; viewed on Jan. 13, 2010. Includes bibliographical references. Also available on microfiche.

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Amichev, Beyhan Y. "Comparison of Techniques for Estimation of Forest Soil Carbon." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9915.

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Soil organic carbon represents the largest constituent of the global C pool and carbon budgets are studied by researchers and modelers in C cycling, global climate change, and soil quality studies. Pedon and soil interpretation record databases are used with soil and ecological maps to estimate regional SOC even though these databases are rarely complete for surface litter and mineral subsurface horizons. The first main objective of the project is to improve the ability to produce soil organic carbon estimates from existing spatial soils datasets, such as STATSGO. All records in the STATSGO Layer table that were incomplete or appeared to be incorrectly filled with a null or zero value were considered invalid. Data sorting procedures and texture lookup tables were used to identify exiting correct (valid) data entries that were used to substitute invalid records. STATSGO soil property data were grouped by soil order, MLRA, layer number, and texture to produce replacement values for all invalid data used to calculate mass SOC. Grouping criteria was specific to each variable and was based on texture designations. The resulting filled and unfilled tables were used with procedures assuming Normal and Lognormal distribution of parameters in order to analyze variation of mass SOC estimates caused by using different computation techniques. We estimated mass SOC to 2 m in Maine and Minnesota using filled and unfilled STATSGO data tables. Up to 54% of the records in Maine and up to 80% of the records in Minnesota contained null or zero values (mostly in fields related to rock fragments) that were replaced. After filling, the database resulted in 1.5 times higher area-weighted SOC. SOC calculated using the Normal distribution assumption were 1.2 to 1.5 times higher than those using the Lognormal transformation. SOC maps using the filled tables had more logical geographic SOC distribution than those using unfilled tables. The USDA Forest Service collects and maintains detailed inventory data for the condition and trends of all forested lands in the United States. A wide range of researchers and landowners use the resulting Forest Inventory and Analysis (FIA) database for analytical and decision making tasks. FIA data is available to the public in transformed or aggregate format in order to ensure confidentiality of data suppliers. The second main objective of this project was to compute SOC (kg m-2) results by FIA forest type and forest type group for three depth categories (25 cm, 1 m, and 2 m) at a regional scale for the 48 contiguous United States. There were four sets of results derived from the filled STATSGO and FIA datasets for each depth class by region: (1) SOC computed by the Lognormal distribution approach for (1a) all soil orders, (1b) without Histosols; and (2) SOC computed by the Normal distribution approach for (2a) all soil orders, (2b) without Histosols. Two spatial forest cover datasets were relevant to this project, FIA and AVHRR. We investigated the effects of FIA inventory data masking for Maine and Minnesota, such as plot coordinates rounding to the nearest 100 arc-second, and the use of 1 km resolution satellite-derived forest cover classes from AVHRR data, on SOC estimates to 2 m by forest type group. SOC estimates by soil mapping unit were derived from fixed STATSGO database tables and were computed by the Lognormal distribution approach including all soil orders. The methods in this study can be used for a variety of ecological and resource inventory assessments and the automated procedures can be easily updated and improved for future uses. The procedures in this study point out areas that could benefit the most during future revisions of STATSGO. The resulting SOC maps are dynamic and can be rapidly redrawn using GIS whenever STATSGO spatial or tabular data undergo updating. Use of pedon data to define representative values for all properties in all STATSGO layers and correlation of STATSGO layers to soil horizons will lead to vast improvement of the STATSGO Layer table and promote its use for mass SOC estimation over large regions.
Master of Science

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CARVALHO, Claudia Csek? Nolasco de. "Infer?ncia fuzzy para predi??o de classes de solo em ?reas de assentamentos na microrregi?o da Mata Alagoana." Universidade Federal Rural do Rio de Janeiro, 2015. https://tede.ufrrj.br/jspui/handle/jspui/2399.

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Sustainable development requires more detailed soil maps with representative information of local reality, helping to conciliate increasing agriculture production and environmental impacts reduction. It is a hard task to achieve considering the Brazil territorial extension and the absence of governmental programs and resources. The Digital Soil Mapping (DSM), through methodologies implementation, has been consolidated as support technique for conventional mapping. Using DSM techniques, we aimed to evaluate a methodological procedure to generate soil maps with refined scale by fuzzy inference, and to map simpler units, which means more adequate areas for the rural settlement development plans. We carried out the study on an area at the microregion of Mata of Alagoas State and the following attributes were integrated by pedologist knowledge: elevation, slope, curvature and profile, topographic wetness index ? derived from a Digital Elevation Model (built by aerophotogrammetric restitution at scale 1:8 000), and geological data at scale 1:50 000. In a first moment, we integrate the thematic layers of 5m resolution pixel related to the attributes. Possibility maps of predefined classes were generate based on rules established by pedological expertise using fuzzy inference. Then, we integrate the evidence maps of classes by weighted mean inference to produce the soils digital map. The predicted digital soil map was opposed to a map elaborated traditionally, and validated by field observation of transects and pre-existent profiles. The comparison between the digital soil map and the conventional indicated a accuracy of 81.2% between the predicted classes of the digital map and the ones on the conventional map units (described on the legend, however not spatialized). Confronting the predicted classes of the digital soil map and the ones identified on field, the observed accuracy was of 74.65%. The Kappa index found was very good, with 0.696 values for the comparison between the digital map and the conventional map and 0.705 between the digital map and field observations. The results demonstrate that legacy maps data may, through the pedologists knowledge and more detailed attribute data, aggregate information and produce more detailed soil maps. Considering the concepts of minimum mappable area, the definitions of pixel sizes suggested for the digital cartographic scale, and the rules for soil survey, the applied methodology allowed, on the used cartographic base, the amplification of the mapping scale from 1:25 000 to 1:15 000.
O desenvolvimento sustent?vel requer mapas de solo mais detalhados com informa??es representativas da realidade local que permitem conciliar aumento da produ??o agropecu?ria com minimiza??o de impactos ambientais. Essa ? uma tarefa dif?cil considerando a extens?o territorial do Brasil e a falta de programas e recursos governamentais. O Mapeamento Digital de Solos-MDS, atrav?s da implementa??o de metodologias, vem se consolidando como t?cnica de apoio ao mapeamento convencional. Usando t?cnicas de MDS, esse trabalho objetivou avaliar um procedimento metodol?gico para gerar mapa de solos com refinamento de escala usando infer?ncia fuzzy para mapear unidades mais simples, portanto mais adequadas aos planos de desenvolvimento dos assentamentos rurais. A ?rea escolhida para teste est? localizada na microrregi?o da Mata do Estado de Alagoas. Para execu??o do trabalho os atributos do terreno eleva??o, declividade, curvatura em perfil, plano de curvatura e ?ndice de umidade topogr?fica derivados de Modelo Digital de Eleva??o-MDE (gerado por restitui??o aerofotogram?trica na escala 1:8.000) e dados geol?gicos em escala 1:50:000, foram integrados atrav?s do conhecimento de ped?logos. Os planos de informa??es, com pixel de 5 m, a partir de regras estabelecidas pela expertise de ped?logos foram fuzzificados e integrados para gerar os mapas de possibilidades de ocorr?ncia para as classes de solo predefinidas. O mapa digital de solos foi produzido pela integra??o dos mapas de possibilidades das classes por infer?ncia m?dia ponderada. O mapa digital de solos predito foi confrontado com mapa elaborado por m?todo tradicional e validado por observa??es em campo ao longo de transectos e por perfis preexistentes. A an?lise comparativa entre o mapa digital de solos e o convencional obteve acur?cia de 81,2 % entre as classes preditas no mapa digital e as contidas nas unidades do mapa convencional (descritas na legenda, por?m n?o espacializadas). Confrontando as classes preditas no mapa digital e as identificadas no campo a acur?cia encontrada foi de 74,65%. A aferi??o das classes pelo ?ndice de Kappa foi considerada muito boa com valores de 0,696 para a compara??o entre o mapa digital versos mapa convencional e 0,705 entre o mapa digital e as observa??es de campo. A pesquisa mostrou que dados contidos em mapas legados de solo podem atrav?s do conhecimento de ped?logos e de dados detalhados de atributos do terreno agregar informa??es e produzir mapa digital de solo com amplia??o da escala e que neste trabalho ? compat?vel com a de levantamentos detalhados (1:15.000).

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Dellamea, Ricardo Batista Cerezer. "Eficiência da adubação a taxa variável em áreas manejadas com AP no Rio Grande do Sul." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/5484.

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This research aim to evaluate the efficiency of variable fertilizer rate in croplands under precision agriculture (PA) in Rio Grande do Sul State with different level of technologies adoption. In the first chapter was evaluated the PF performance in a small farm with 19 ha in which was cropped soybean in 2005/06 and 2006/07 located in central of Rio Grande do Sul State. In this cropland were used the equipments and technology available in this farm. It was determined the spatial variability of soil attributes by grid sampling with 100 x 100 m also the yield map was done by manual sampling of crop and variable fertilizer rates by soil management zones. The PA increased in average 8% the soybean yield.The soil attribute that had better correlation with yield was soil organic matter. The economic analysis show a return of R$ 72,05 ha-1 due inputs save and increase yields. Also, the PA had a 29% increase of fertilizer use efficiency. In the second chapter were evaluated 6 farms totalizing 138 ha of soybean and 96 ha of maize linked to Aquarius Project of PA located in different counties of Alto Jacui, RS. The main activities evaluated were yield map with a Massey Ferguson combine, model MF 34, fertilizer variable rate with centrifuge force distribution Hercules 10.000 from STARA. The average of result shows decrease of 33.1 and 36.8% in fertilizer inputs and increase of 10 and 14% in soybean and maize yields, respectively. The efficiency use of fertilizer was increased in 47.2 and 62.8% allowing a return of R$ 143.34 ha-1 to soybean and R$ 312.44 ha-1 to maize.
Este trabalho teve por objetivo avaliar a eficiência da adubação a taxa variável em áreas manejadas com agricultura de precisão (AP) no Rio Grande do Sul, com diferentes níveis tecnológicos. No capítulo 1 foram analisados 19 ha cultivados com soja nas safras 2005/06 e 2006/07, localizados em uma pequena propriedade no município de Silveira Martins, região central do estado do Rio Grande do Sul. Nessa área foram utilizados os recursos tecnológicos disponíveis na propriedade. Com isso, foram determinadas as variabilidades espaciais dos atributos do solo através de um grid com 100 x 100 m, confeccionados mapas de produtividade de forma manual, aplicados os insumos em diferentes doses por zonas de manejo. O manejo localizado proporcionou uma economia de 17% na quantidade total dos insumos e um aumento de 8% na produtividade da soja, o que representou um retorno financeiro bruto de R$ 72,05 ha-1 e um aumento na eficiência de 29% em relação ao manejo tradicional. No capítulo 2 foram analisados 138 ha com a cultura da soja e 96 ha com a cultura do milho na safra 2006/07, distribuídos em 6 áreas pertencentes a produtores ligados ao Projeto Aquarius de AP e localizadas em diferentes municípios na região do Alto Jacuí RS. A colheita georreferenciada foi realizada com o auxílio de uma colhedora marca Massey Ferguson modelo MF34 e as aplicações, a taxas variáveis de insumos, foram realizadas através do distribuidor centrífugo Hércules 10000, marca Stara. Para realizar a análise da eficiência do uso de fertilizantes foram comparadas as entradas e saídas de fertilizantes e grãos nos talhões com AP, com a estimativa média de entradas e saídas dos talhões com AC que serviram de testemunhas dentro das propriedades correspondentes. Os resultados evidenciam uma redução média de 33,1 e 36,8% no uso dos insumos e um aumento de 10 e 14% no rendimento das culturas da soja e milho, respectivamente. A eficiência do uso de fertilizantes foi incrementada em 47,2 e 55,1% com o uso da AP, quando consideradas as quantidades totais de fertilizantes, passando para 31,3 e 62,8%, quando considerados os recursos financeiros, proporcionando um retorno de R$ 143,34 ha-1 para a cultura da soja e R$ 312,44 ha-1para a cultura do milho.

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Miranda, Elka Élice Vasco de [UNESP]. "Modelagem e mapas de capacidade suporte de carga de solos cultivados com cana-de-açúcar." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/101733.

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Universidade Estadual Paulista (UNESP)
New studies must consider and quantify the load level that a determined soil can receive and in what management condition this soil can be handled without suffering physical alterations and additional compaction. The objectives of this work were to quantify the preconsolidation pressure, suggesting it as a quantitative indicator of the soil structural sustentabilidade cultivated with sugar cane; to get models that allow to predict the behavior of the soil structure cultivated with sugar cane in function of the preconsolidation pressure and the water content; to get agricultural traffic maps in function of water content and the preconsolidation pressure of the soil using geostatistics resources; and to evaluate the soil mechanical resistance, based on cone index and water content variation under several types of soils. Soil samples from several soil classes were collected cropped with sugar cane and areas that varied from 4.88 and 17.86 ha. The maps that illustrated the spatial variability of the several physical attributes were made using statistical and geostatistical resources. The models of the soil load capacity satisfactory modeled the behavior of the soil structure in function of the water content and depth, helping the maximum load prediction that this soil can receive without compromising its structure. The obtained models were sensible to identify the consolidation structure, identifying the layers and grids with huge mechanical resistance. The use of geostatistical tools and mapping the studied attributes showed a promising tool to take decisions about the system, aiming at, over all the soil structure sustentation. The maps of the soil load capacity constituted an efficient tool to locate 4 areas into the field with compromised structure, making possible to plan the correct dimension of the machinery... (Complete abstract, click electronic access below)

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Cherubin, Maurício Roberto. "EFICIÊNCIA DE MALHAS AMOSTRAIS UTILIZADAS NA CARACTERIZAÇÃO DE ATRIBUTOS QUÍMICOS EM LATOSSOLOS MANEJADOS COM AGRICULTURA DE PRECISÃO." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/4915.

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The georeferenced soil sampling using sampling grids is the main strategy of precision agriculture (PA) to recognize the spatial variability of soil attributes, allowing manage them in site-specific. In this context, the objective of the work was to evaluate the efficiency of using different sizes of sampling grids in the characterization of spatial variability of chemical attributes in Oxisols managed with PA in Southern Brazil. Therefore, the work consists of three studies. In studies one and two were used 60 areas (6,046.55 ha), located in 23 counties of North region of Rio Grande do Sul (RS). The areas were sampled using regular grids of 100 x 100 m (20 areas), 142 x 142 m (20 areas) and 173 x 173 m (20 areas), being that 10 areas of each grid were collected from 0.00-0.10 m and 10 areas from 0.00-0.15 m. The spatial variability of acidity attributes (pHwater and base saturation) and bases related (Ca and Mg) (study one) and the levels of P and K (study two) were analyzed by descriptive statistics and geostatistics. In study three, was used an area of 41.96 ha, located in Boa Vista das Missões - RS, where was made the collect of soil in seven sizes of sample grids, 50 x 50 m, 75 m x 75, 100 x 100 m, 125 m x 125, 150 x 150 m, 175 m and 200 x 175 x 200 m, at depth of 0.00-0.10 m. The levels of P and K were analyzed by descriptive statistics and geostatistics, and the similarity of thematic maps was compared by the coefficient of relative deviation (CRD) and by Pearson correlation matrix (p <0.05). The areas of Oxisols managed with PA in RS, show moderate acidity and high fertility, with the exception of subareas that presents limiting P levels. Independently of the depth sampled, the grid sample sizes used in RS state, in general, are not efficient in capturing the different scales of variability in soil chemical properties. According as increase the sample grid the thematic maps of P (CRD: 24.0 to 36.2%) and K (CRD: 11.7 to 19.4%) show more dissimilar to those obtained in smaller grid (50 x 50 m) considered as reference. Thus, the reduction of sampling grid sizes increases the accuracy of the information generated through thematic maps, allowing to do prescriptions of lime and fertilizers on site-specific with greater efficiency, and should be recommended in future sampling plans of soil adopted in PA areas in Southern Brazil.
A amostragem georreferenciada de solo utilizando malhas regulares é a principal estratégia da agricultura de precisão (AP) para reconhecer a variabilidade espacial dos atributos de solo, possibilitando manejá-los em sítio-específico. Nesse contexto, o objetivo do trabalho foi avaliar a eficiência do uso de diferentes dimensões de malhas amostrais na caracterização da variabilidade espacial de atributos químicos em Latossolos Vermelhos manejados com AP no Sul do Brasil. Para tanto, o trabalho constitui-se de três estudos. Nos estudos um e dois utilizaram-se 60 áreas (6.046,55 ha), localizadas em 23 municípios da região Norte do Rio Grande do Sul (RS). As áreas foram amostradas utilizando malhas regulares de 100 x 100 m (20 áreas); 142 x 142 m (20 áreas) e 173 x 173 m (20 áreas), sendo que 10 áreas de cada malha foram coletadas de 0,00-0,10 m e 10 áreas de 0,00-0,15 m. A variabilidade espacial dos atributos de acidez (pHágua e saturação por bases) e bases relacionadas (Ca e Mg) (estudo um) e dos teores de P e K (estudo dois) foram analisadas por meio da estatística descritiva e geoestatística. No estudo três, utilizou-se uma área de 41,96 ha, localizada em Boa Vista das Missões RS, onde foi realizada a coleta de solo em sete dimensões de malha amostral, 50 x 50 m, 75 x 75 m, 100 x 100 m, 125 x 125 m, 150 x 150 m, 175 x 175 m e 200 x 200 m, na profundidade de 0,00-0,10 m. Os teores de P e K foram analisados por meio da estatística descritiva e da geoestatística, e a similaridade dos mapas temáticos foi comparada pelo coeficiente de desvio relativo (CDR) e pela matriz de correlação de Pearson (p <0,05). As áreas de Latossolos Vermelhos manejadas com AP no estado do RS apresentam moderada acidez e alta fertilidade, com exceção de locais que apresentam teores limitantes de P. Independente da profundidade amostrada, as dimensões das malhas amostrais utilizadas no RS, em geral, não são eficientes em captar as diferentes escalas de variabilidade dos atributos químicos do solo. À medida que aumenta a malha amostral os mapas temáticos de P (CDR: 24,0 a 36,2%) e K (CDR: 11,7 a 19,4%) mostram-se mais dissimilares aos obtidos na menor malha (50 x 50 m) considerada como referência. Desta forma, a redução da dimensão da malha amostral aumenta a acurácia das informações geradas por meio de mapas temáticos, permitindo realizar prescrições de corretivos e fertilizantes em sítio-específico com maior eficiência, e devem ser preconizadas em futuros planos de amostragem de solo adotados nas áreas de AP no Sul do Brasil.

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Lopes, Felipe de Araújo. "Adubação em doses variadas em citros." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11148/tde-20102010-142822/.

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O cultivo dos citros é de grande importância no mundo, e no Brasil é uma das culturas mais representativas das exportações do país. A agricultura de precisão (AP) é descrita como um conjunto de ferramentas, que possibilitam gerenciar o sistema de produção a partir de informações georreferenciadas e manejar variabilidades espaciais das lavouras. A AP é utilizada em larga escala em culturas anuais, mostrando resultados quanto ao melhor gerenciamento das informações e racionalização dos insumos. Considerando a importância dos citros para a economia do estado de São Paulo e desejando-se aprimorar o seu processo produtivo, objetivouse com este trabalho identificar as variabilidades espaciais dos atributos e elementos químicos no solo e nas folhas, e produtividade de pomares comerciais de laranja, comparando-se o manejo tradicionalmente utilizado pela fazenda com os efeitos das adubações em taxa variável. Para isso, foram utilizadas duas áreas localizadas na Fazenda Quatrirmãs, no município de Botucatu-SP, de 25,7 hectares cada uma, diferenciadas pelo tipo de solo, altitude e ano de plantio, que foram acompanhadas por duas safras desde o ano de 2008. Foram estabelecidos dois tratamentos: aplicações em dose fixa (DF) e dose variável (DV). Na primeira safra, foram retiradas amostras de solo em três diferentes padrões e densidades, para contrastar os níveis de fertilidade na faixa de adubação na profundidade de 0-0,2 m (2 amostras ha-1) e 0,2-0,4 m (1 amostra ha-1), e no centro da rua de 0-0,2 m de profundidade (1 amostra ha-1). A partir das análises das amostras retiradas na faixa de adubação na profundidade de 0-0,2 m, foram calculadas as recomendações de aplicação de calcário e de fontes de nitrogênio, fósforo e potássio para o tratamento DV, que foram aplicadas por uma máquina protótipo capaz de variar as doses automaticamente, baseadas no mapa de prescrição. Na safra 2009/2010 foram retiradas amostras de solo e folhas georreferenciadas, separando-se os tratamentos. As colheitas foram registradas em ambas as safras e forneceram dados para o mapeamento da produtividade das áreas. Os resultados das amostragens georreferenciadas de solo mostraram variabilidade espacial dos atributos. As médias dos valores de P foram classificadas como médio, nas áreas em ambos os tratamentos. Os valores médios de K variaram entre alto e médio, para DF e DV, respectivamente, na área de solo argiloso e médio para os dois tratamentos da área 2 (solo arenoso). Os níveis médios de V% foram classificados como médio na área 1 e baixo na área 2, sem diferença entre tratamentos. As adubações em taxa variável resultaram em economia de 230 kg ha-1 de nitrogênio, 5 kg ha-1 de fósforo e 257 kg ha-1 de potássio, em média, nos dois talhões, quando somadas as safras estudadas. As produtividades foram elevadas em mais que o dobro nas áreas, aumentando de 19,3 para 39,3 t ha-1 (DF) e 41,8 t ha-1 (DV) na área 1, e de 15,3 para 33,4 t ha-1 (DF) e 33,3 t ha-1 (DV) na média dos valores da área 2. Os teores foliares de N, P e K não diferiram entre os tratamentos e suas médias foram identificadas como altas nas duas áreas, indicando o potencial do uso desta ferramenta nas áreas estudadas.
The cultivation of citrus has great importance in the world and in Brazil is one of the most representative crops for exports. Precision agriculture (PA) is described as a set of tools that allow managing the production system based on georeferenced information related to the spatial variability of crops. The PA is used in large-scale on annual crops showing results concerning improved information management and the rationalization of inputs use. Considering the importance of citrus to the economy of the Sao Paulo state and wishing to improve production practices the aim of this work was to identify the spatial variability of the attributes and elements of soil, leaves and yield of commercial orange orchards and compare management traditionally used by the farm with the effects of variable rate fertilization. The work was conducted in two areas located in Botucatu-SP, 25.7 hectares each, differentiated by soil type, elevation and year of planting. The areas were monitored and interfered for two seasons since the year 2008. Two treatments were established: applications of a constant rate (CR) and spatially variable rate (VR). In the first year, soil samples were collected in three different patterns and densities at a depth of 0-0.2 m (2 samples ha-1) and 0.2-0.4 m (1 sample ha-1) in the fertilization strip and in the between trees rows at 0-0.2 m depth (1 sample ha-1). From the analysis of samples taken in the range of fertilization at a depth of 0-0.2 m recommendations were calculated for liming and sources of nitrogen, phosphorus and potassium for VR treating that were applied by a prototype machine capable of varying rates automatically based on the prescription map. In the 2009/2010 year, the georeferenced samples were collected from soil and leaves georeferenced separating the treatments. The samples were recorded in both seasons and provided data for yield mapping of the areas. The results of georeferenced soil samples showed spatial variability of attributes. The average values of P were classified as \"medium\", for the areas in both treatments. The average values of K ranged from \"high\" and \"medium\" for CR and VR, respectively, in clay soil area and \"medium\" for the treatments of area 2. Mean levels of V% were classified as \"medium\" in the area and a \"low\" in area 2, with no difference between treatments. The variable rate fertilization resulted in savings of 230 kg ha-1 nitrogen, 5 kg ha-1 of phosphorus and 257 kg ha-1 potassium on average in the two plots. The yields increased from 19.3 to 39.3 t ha-1 (CR) and 41.8 t ha-1 (VR) in area 1 and from 15.3 to 33.4 t ha-1 (CR) and 33.3 t ha-1 (VR) of area 2. Leaf N, P and K did not differ between treatments and their averages were identified as high in both areas supporting the potential use of this tool.

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Lopa, Afrin Jahan. "Application of in situ shallow subsurface soil spectroscopy (S4) to archaeology and forensics." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1619718858276667.

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Miranda, Elka Élice Vasco de 1975. "Modelagem e mapas de capacidade suporte de carga de solos cultivados com cana-de-açúcar /." Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/101733.

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Abstract: New studies must consider and quantify the load level that a determined soil can receive and in what management condition this soil can be handled without suffering physical alterations and additional compaction. The objectives of this work were to quantify the preconsolidation pressure, suggesting it as a quantitative indicator of the soil structural sustentabilidade cultivated with sugar cane; to get models that allow to predict the behavior of the soil structure cultivated with sugar cane in function of the preconsolidation pressure and the water content; to get agricultural traffic maps in function of water content and the preconsolidation pressure of the soil using geostatistics resources; and to evaluate the soil mechanical resistance, based on cone index and water content variation under several types of soils. Soil samples from several soil classes were collected cropped with sugar cane and areas that varied from 4.88 and 17.86 ha. The maps that illustrated the spatial variability of the several physical attributes were made using statistical and geostatistical resources. The models of the soil load capacity satisfactory modeled the behavior of the soil structure in function of the water content and depth, helping the maximum load prediction that this soil can receive without compromising its structure. The obtained models were sensible to identify the consolidation structure, identifying the layers and grids with huge mechanical resistance. The use of geostatistical tools and mapping the studied attributes showed a promising tool to take decisions about the system, aiming at, over all the soil structure sustentation. The maps of the soil load capacity constituted an efficient tool to locate 4 areas into the field with compromised structure, making possible to plan the correct dimension of the machinery... (Complete abstract, click electronic access below)
Orientador: Kleber Pereira Lanças
Coorientador: Reginaldo Barboza da Silva
Banca: Célia Regina Lopes Zimback
Banca: Antonio Gabriel Filho
Banca: Marlene Cristina Alves
Banca: Moacir de Souza Dias Junior
Doutor

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Merkley, Brett J. "Sources and Pathways of Lead Contamination in Urban Community Gardens in Toledo, Ohio." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1555621213052896.

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Eitelwein, Mateus Tonini. "DEFINIÇÃO DE ESTABILIDADE PRODUTIVA E RELAÇÃO COM ATRIBUTOS DE SOLO EM ÁREAS MANEJADAS COM AGRICULTURA DE PRECISÃO." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/4919.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The mapping of grain yield is the main tool for analysis of the results of the techniques of precision agriculture used. In this sense, the aim of this study was to describe the equipment and clarify the current state of the art mapping yield (Chapter I), to analyze the occurrence of similarity between maps over time using different cultures (Chapter II), and finally, determine the influence that soil properties exert on crop yields (Chapter III). In Chapter I deal with the basic equipment that composes a set of monitoring harvest, giving emphasis on yield sensors on the market, the sequence shows the possibilities of using yield maps for management areas. For analysis of yield stability (Chapter II), there were four areas with a history of monitoring four crops of soybean, corn, wheat and oats. The areas were divided by a regular grid (20 x 20 m) for each raster is assigned the value of average yield of the points that were inside. Data were normalized to enable the temporal analysis. The correlation between soil properties and productivity (Chapter III) was evaluated in an area of 88 acres using the Spearman correlation. The soil samples were taken manually auger at a depth from 0 to 0.1 m, over a regular grid (50 x 50 m). The yield values of these points were determined by averaging the sample points using different radius in three cultures. The results demonstrated the presence of yield stability, especially in areas with large variation in yield in one year. The methodology should be used with caution, especially in places where there is a tendency to homogeneity in yield. The radius sample used to determine the value of yield point has a direct influence on the values of the correlations. Increasing the radius to the sample value of 30 meters provided significant gradual increase in the values of correlations. The phosphorus was the nutrient that showed high positive correlation with yield, despite being above the levels described for the critical state.
O mapeamento da produtividade de grãos constitui a principal ferramenta de análise dos resultados das técnicas de agricultura de precisão utilizadas. Neste sentido o objetivo do estudo foi descrever os equipamentos e esclarecer o estado atual da arte de mapeamento da produtividade (capitulo I), analisar a ocorrência de similaridade entre mapas ao longo do tempo utilizando diferentes culturas (capitulo II) e, por fim, determinar a influência que os atributos do solo exercem na produtividade das culturas (capitulo III). No capítulo I são descritos os equipamentos básicos que compõe um conjunto de monitoramento de colheita, dando ênfase para os sensores de produtividade presentes no mercado, na sequencia são apresentadas as possibilidades de utilização dos mapas de produtividade para gerenciamento das áreas. Para análise da estabilidade produtiva (capitulo II), foram utilizadas quatro áreas com um histórico de monitoramento de quatro safras das culturas da soja, milho, trigo e aveia. As áreas foram divididas por uma malha quadricular (20 x 20 m), para cada quadricula se atribuiu o valor de produtividade médio dos pontos que se encontravam no seu interior. Os dados foram normalizados para possibilitar a análise temporal. A correlação entre atributos do solo e a produtividade (capitulo III) foi avaliada em uma área de 36 hectares utilizando a correlação de Spearman. As amostragens de solo foram realizadas manualmente com trado calador na profundidade de 0 - 0,1 m, através de uma malha regular (50 x 50 m). Os valores de produtividade destes pontos foram determinados através da média dos pontos utilizando diferentes raios amostrais em três culturas. Os resultados demonstraram a presença de estabilidade produtiva, sobretudo em áreas que apresentam grande oscilação na produtividade em um mesmo ano. A metodologia deve ser utilizada com cautela, principalmente em locais onde há uma tendência à homogeneidade na produtividade. O raio amostral utilizado para determinar o valor de produtividade de um ponto tem influencias diretas sobre os valores das correlações. O aumento do raio amostral até o valor de 30 metros proporcionou aumentos graduais significativos nos valores das correlações. O fósforo foi o nutriente que apresentou maiores correlações positivas com a produtividade, mesmo estando acima dos teores críticos descritos para o estado.

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Lorençon, Jonas. "AVALIAÇÃO DO PERFIL QUÍMICO DO SOLO NA PRODUTIVIDADE DA SOJA (Glycine max) ATRAVÉS DE MAPAS DE COLHEITA." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/4833.

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Agribusiness as a whole has evolved along with the global modernization. Precision Agriculture (PA) is a technology that has been adding in yield of major crops such as soybeans, corn, wheat and coffee. The generation of yield maps and maps of fertility are likely to generate information to make further interventions or remedial applications in crops. Aiming to investigate the relationship between yield maps of soybean with chemical indicators of soil fertility work was undertaken on the property of Seeds Bee the municipality of Coxilha - RS. The study began in 2005 until 2013 in the collection of data on productivity done through maps worked with the aid of Ag Leader SMS software, totaling 5 maps of soybean. The yield maps are generated from information collected in the harvest product. These figures are achieved with devices equipped with GPS, humidity sensor and productivity throughout the harvest generate localized information. From this, the maps was unified into one with three classifications of production zones: high, medium and low. With information from areas of high and low production soil samples were collected up to 1 m deep by 5 points geo-referenced each distinct zone (high and low). In the evaluations of the analysis it was realized that the pH and base saturation and sulfur were the attributes that have higher productivity in relation to depth. The match had a positive influence on productivity up to 0.20 m depth. Organic matter showed no similarities with productivity. In view of this correlation with the factors that influence the production allow the producer a decision which product to apply and how much more needs to be based on georeferenced data from your area. This achieves - rational use of natural resources and therefore the environment can still raise productive crops ceilings.
O Agronegócio como um todo vem evoluindo junto com a modernização global. A agricultura de Precisão (AP) é uma tecnologia que vem agregando na produção de grãos das grandes culturas como soja, milho, trigo e café. A geração de mapas de produtividade e de mapas de fertilidade são possibilidades de gerar informações para posteriormente fazer as intervenções ou aplicações de corretivos nas lavouras. Com o objetivo de Investigar a relação entre mapas de produtividade das culturas de soja com indicadores químicos da fertilidade do solo foi realizado um trabalho na propriedade da Sementes Bee no município de Coxilha RS. O estudo iniciou-se em 2005 até 2013 na coleta de informações de produtividade feito através de mapas trabalhados com auxílio do software SMS Ag Leader, totalizando 5 mapas da cultura da soja. Os mapas de produtividade são gerados a partir de informações coletadas na colheita do produto. Esses dados são conseguidos com equipamentos equipados com GPS, sensor de umidade e de produtividade que no decorrer da colheita geram informações localizadas. A partir disso, unificou-se os mapas em um só com 3 classificações de zonas de produção: alta, média e baixa. Com a informação das zonas de alta e baixa produção foram coletadas amostras de solo até 1 m de profundidade em 5 pontos georrefenciados de cada zona distinta (alta e baixa). Nas avaliações das análises percebeu-se que O pH e saturação de bases e enxofre foram os atributos que deram maior relação com a produtividade em profundidade. O fósforo teve influência positiva com a produtividade até os 0,20 m de profundidade. A matéria orgânica não apresentou semelhanças com a produtividade. Em vista disso a correlação com fatores que influenciam na produção possibilitam ao produtor uma decisão de qual produto aplicar e em que quantidade, mais precisa por estar baseada em dados georreferenciados de sua área. Com isso consegue-se racionalizar o uso de recursos naturais e conseqüentemente do meio ambiente podendo ainda elevar os tetos produtivos das lavouras.

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O'Hearn, Connor E. "Sustainable Coffee Farming in Hawai'i: Gathering GIS Data to Inform Development and Planning in the Rainforest and Protect Natural and Historic Features." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami161890711019104.

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Cocco, Leonardo Burin. "UTILIZAÇÃO DE FERRAMENTAS DE AGRICULTURA DE PRECISÃO NA DEFINIÇÃO DE ZONAS DE MANEJO." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/4832.

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Precision agriculture (AP) appears as a permissible tool to manage rationally the spatial and temporal variability of soil chemical attributes in order to effectively maximize the use of agricultural areas. However, in some situations visualized a low correlation between the chemical soil properties and crop productivity, emphasizing the need for development of AP to seek alternatives and tools for the definition of management zones. In recent years, they have gained prominence studies of parameter attributes of plant canopies, and the Vegetation Index (NDVI) the best known. This study aimed to evaluate the use of AP tools to define management zones in the central region of Rio Grande do Sul. The work was conducted with the culture of the agricultural year 2014/15 corn in an area of 15.1 hectares in the municipality of Julio de Castilhos, RS, managed with irrigation center pivot. The spatial variability of soil attributes and plants was characterized based on the collection of information on a sampling grid of 0.5 ha, totaling 32 points in the experimental area. The Landsat satellite images (NDVI) with a spatial resolution of 30 x 30 m were processed enabling the production of productivity map and the definition of management zones in the area. The soil properties have high variance in the standard deviation (S) and coefficient of variation (CV%) of phosphorus (18.16 and 42.46), potassium (38.263 and 25.80), aluminum saturation (4,63 and 130.14) sulfur (6.72 and 40.57) and manganese (7.32 and 30.23). The analysis of the statistical and geostatistical to dry mass (28,10% CV and r2 = 0.96) and corn (11.85% CV and r2 = 0.99). The Pearson correlation was significant positively to productivity of corn kernels indicated the clay, base saturation, calcium, SMP index, magnesium and NDVI; indicated dry weight organic material, SMP index CTC pH7 and magnesium. Among the different methods of zones positive correlation between dry matter areas of stubble and productivity with altitude zone, chemical attributes zone and NDVI zone. The use of satellite images made it possible to guarantee the evaluation of different management zones.
A agricultura de precisão (AP) surge como uma ferramenta permitindo manejar de forma racional a variabilidade espacial e temporal dos atributos químicos do solo com objetivo de maximizar eficientemente o uso das áreas agrícolas. Entretanto, em algumas situações visualiza-se uma baixa correlação entre os atributos químicos do solo e a produtividade das culturas, destacando-se a necessidade da evolução da AP em buscar ferramentas e alternativas para a definição de zonas de manejo. Nos últimos anos, têm ganhado destaque os estudos sobre parametrização de atributos dos dosséis vegetais, sendo o Índice de Vegetação por Diferença Normalizada (NDVI) o mais conhecido. O presente trabalho teve como objetivo avaliar a utilização de ferramentas de AP na definição de zonas de manejo na região central do Rio Grande do Sul. O trabalho foi conduzido com a cultura do milho (Zea mays L.) ano agrícola 2014/15, numa área de 15,1 hectares no município de Júlio de Castilhos, RS, manejada com irrigação por pivô central. A variabilidade espacial de atributos de solo e de plantas foi caracterizada com base na coleta de informações numa malha amostral de 0,5 ha, totalizando 32 pontos na área experimental. As imagens de satélite Landsat (NDVI) com resolução espacial de 30 x 30 m foram processadas possibilitando a confecção de mapa de produtividade e a definição de zonas de manejo da área. Os atributos do solo possuem alta variância no desvio padrão (S) e coeficiente de variação (CV%) do fósforo (18,10 e 42,46), potássio (38,26 e 25,80), saturação por alumínio (4,63 e 130,14), enxofre (6,72 e 40,57) e manganês (7,32 e 30,23). A análise da estatística e geoestatísticos para produção de massa seca (28,10 CV % e r2=0,96) e produtividade grãos de milho (11,85 CV % e r2=0,99). A correlação linear de Pearson foi significativa positivamente para produtividade de grãos de milho indicou a argila, saturação por bases, cálcio, índice SMP, magnésio e NDVI; massa seca indicou matéria orgânica, índice SMP, CTC pH 7 e magnésio. Entre os diferentes métodos das zonas de manejo a correlação positiva entre as zonas de massa seca da resteva e produtividade com zona de altitude, zona atributos químicos e zona de NDVI. A utilização de imagens de satélites possibilitou a garantia da avaliação de diferentes zonas de manejo.

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Corassa, Geomar Mateus. "MANEJO POR AMBIENTE: ATRIBUTOS DE SOLO E DESEMPENHO DE CULTIVARES DE SOJA." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4937.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The crop productivity mapping is an important precision farming tool enabling more efficient spatial management of agricultural areas. In this sense, the objective of this work was to identify and analyze zones with different grain yield potential (Article I), check the association of chemical and physical properties of the soil with the yield zones (Article II), and evaluate the agronomic performance of six soybean cultivars in zones with different grain yield potential. For the definition of the yield zones were used three harvest maps of different cultures in two experimental areas. The maps were filtered and the defined zones and grouped from the overlap of crops (Article I). The search for chemical and physical atributes of the soil associated with grain yield was performed by systematic soil collection, according to grain yield zones (high, medium and low) (Article II), and analyzed 80 chemical variables and 33 physical variables by using descriptive statistics and ranked by principal component analysis (PCA). The agronomic performance of soybean cultivars in different grain yield zones (Article III) was evaluate in two agricultural areas, being allocated experiments in the random block design in factorial 3x6, with three grain yield zones (high, medium and low) and six soybean cultivars (BMX Ativa RR, Fundacep 65 RR, FPS Urano RR, FPS Júpiter RR, Nidera 5909 RG and BMX Força RR), with three replications. The results showed that the use of a historical series of harvest maps is an efficient tool to characterize sites with different grain yield potential, in addition to serving as a base for improving the spatial management of agricultural areas. The systematic soil sampling was able to reveal explanatory variables for grain yield, and the order for intervention in chemical attributes in the área is: Liming, phosphate fertilization and potassium fertilization. The presence of attributes of difficult management in the short time (organic matter and clay) associated with grain yield potential suggests the crop management in the management zones. The yield zones influenced the grain yield of soybean cultivars, and the cultivar BMX Força RR presented its highest grain yield in the ZB, whereas NA 5909 RG was more productive in the ZA and ZM. The cultivar BMX Ativa RR was on average more productive and more stable. The results indicate that the positioning of soybean cultivars in accordance with management zones is a important strategy for the precision agriculture and characterized as a new concept of the ―multi-cultivars‖ sowing.
O mapeamento da produtividade das culturas é uma importante ferramenta da agricultura de precisão permitindo o manejo espacial e temporal mais eficiente das áreas agrícolas. Neste sentido, o trabalho teve por objetivo identificar e analisar zonas com diferentes potenciais de rendimento de grãos (Artigo I), verificar a associação de atributos químicos e físicos do solo com as zonas de rendimento (Artigo II) e, avaliar o desempenho agronômico de seis cultivares de soja em zonas de alto (ZA), médio (ZM) e baixo (ZB) potencial de rendimento de grãos. Para a definição das zonas de rendimento foram utilizados três mapas de colheita de diferentes culturas em duas áreas experimentais. Os mapas foram filtrados e as zonas definidas e agrupadas a partir da sobreposição das safras (Artigo I). A busca por atributos químicos e físicos do solo associados ao rendimento de grãos foi procedida por meio da coleta sistemática do solo, de acordo com as zonas de rendimento (alto, médio e baixo) (Artigo II), sendo analisadas 80 variáveis químicas e 33 variáveis físicas por meio da estatística descritiva e ranqueadas por meio da análise de componentes principais (ACP). O desempenho agronômico de cultivares de soja nas diferentes zonas de rendimento (Artigo III) foi avaliado em duas áreas agrícolas, sendo os experimentos alocados em delineamento de bloco aos acaso em esquema fatorial 3x6, com três zonas de rendimento (alto, médio e baixo) e seis cultivares de soja (BMX Ativa RR, Fundacep 65 RR, FPS Urano RR, FPS Júpiter RR, NA 5909 RG e BMX Força RR), com três repetições. Os resultados comprovaram que o uso de uma série histórica de mapas de colheita é uma ferramenta eficiente para caracterizar locais com diferentes potenciais de rendimento, além de servir como base para a melhoria da gestão espacial das áreas agrícolas. A amostragem sistemática do solo foi capaz de revelar variáveis explicativas para o rendimento de grãos, sendo a ordem para intervenção em atributos químicos na área: calagem, fertilização fosfatada e fertilização potássica. A presença de atributos de difícil manejo em curto prazo (matéria orgânica e argila) associados ao rendimento de grãos sugere o manejo das culturas por zona de manejo. As zonas influenciaram o rendimento de grãos das cultivares de soja, sendo que a cultivar BMX Força RR apresentou seu maior rendimento na ZB, enquanto que NA 5909 RG, foi mais produtiva em ZA e ZM. A cultivar BMX Ativa RR foi em média a mais produtiva e mais estável. Os resultados indicam que o posicionamento de cultivares de soja de acordo com zonas de manejo é uma importante estratégia para a agricultura de precisão e se caracteriza como um novo conceito de semeadura ―multi-cultivares‖

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Colombàs, Borràs Margalida. "Nivells d'elements traça i macroelements als sòls de les Illes Balears." Doctoral thesis, Universitat de les Illes Balears, 2014. http://hdl.handle.net/10803/663752.

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[cat] S'estudia l’estat actual del contingut de set macroelements (Ca, Mg, Al, Fe, K, Na i P) i nou elements traça (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) en els sòls de les Illes Balears. A partir de la determinació del contingut total de macroelements i elements traça mitjançant la digestió de les mostres de sòl per via humida amb aigua règia i s’estudien les relacions que hi ha entre ells i amb les característiques fisicoquímiques del sòl. També s’estudia el comportament dels elements en funció de l’illa, la profunditat i a una sèrie de sòls representatius de les Illes Balears. Finalment, s’estableix una proposta de nivells de fons i valors de referència dels elements traça a les Illes Balears comparant diferents mètodes, amb la finalitat de poder tenir criteris que permetin identificar una possible alteració dels continguts d’aquests elements. Els continguts medians (mg kg-1) obtinguts pels elements traça estudiats a les mostres superficials han estat: As 15,8, Cd 0,42, Co 9,6, Cr 57,3, Cu 18,7, Mn 467,1, Ni 29,3, Pb 18,7, Zn 53,9. Respecte el comportament en funció de l’illa, el Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn presenten valors més baixos de concentració a Formentera i els més alts a Menorca, amb situacions intermèdies a les altres dues illes, més semblants a Menorca en el cas de Mallorca i més semblants a Formentera en el cas d’Eivissa. L’As no presenta diferències de concentració entre illes. Aquest comportament dels elements traça és invers al del CCE i del pH, així, llocs on tenen un contingut elevat de carbonats tenen un baix contingut d’elements traça. Les correlacions entre la majoria de paràmetres estudiats són significativament altes (p<0,05) o molt altes (p<0,001). Tot i això, els coeficients dels llims, CO, pH, Na, P i Mg amb la resta de paràmetres són relativament baixos, indicant un baix efecte d’aquests paràmetres sobre els elements traça. Les relacions entre l’Al, Fe, K, As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn són altament significatives i presenten majoritàriament coeficients positius elevats entre ells, suggerint un origen comú i natural d’aquests. Pel que fa l’estudi dels elements traça sobre sòls representatius de les Illes Balears s’ha observat que sobre materials calcaris, els sòls menys diferenciats presenten els continguts més baixos d’elements traça i els més evolucionats són els que presenten els continguts més elevats. Per ordre, els continguts més baixos corresponen als Arenosols de sistemes dunars litorals, seguits de Cambisols sobre margues, Calcisols, Cambisols sobre margues i, finalment, Luvisols com a tipologies més diferenciades i amb continguts d’elements traça més elevats. D’altra banda, sobre les roques olivíniques del Keuper es desenvolupen sòls amb alts continguts de P, Fe, Co, Cr, Mn i Ni i baixos de Cd. Els rangs de concentració (mg kg-1) de la població de fons dels diferents elements traça per als sòls de les Illes Balears amb el mètode del gràfic de probabilitat han estat: As 2,5-28,2, Cd 0,03-0,74, Co 1,7-16,9, Cr 12,9-95,3, Cu 2,6-32,6, Mn 53,3-793,5, Ni 5,5-49,6, Pb 0,3-34,7, Zn 9,6-96,4. Els valors mitjans de la població de fons han resultat molt semblants amb els cinc mètodes utilitzats. Tot i això, s’aprecia que el rang més ampli de població de fons, i per tant el valor de referència més alt, s’ha obtingut amb el mètode del diagrama de caixes, seguit dels mètodes del rang normal d’una mostra, del de la funció de la distribució calculada, del mètode del gràfic de probabilitat i, per acabar, del mètode de la mediana, amb el que s’obté el rang més estret, i per tant del valor de referència més baix.
[spa] Se han investigado 508 perfiles de las Islas Baleares y la variabilidad en ellos de los niveles de macroelementos (Ca, Mg, Al, Fe, K, Na i P), elementos traza (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) y algunas propiedades del suelo (arenas, limos, arcillas, carbonato cálcico equivalente -CCE-, carbono orgánico, pH y capacidad de intercambio catiónico). Los puntos de muestreo seleccionados presentaban una mínima influencia antropogénica y las muestras de suelo fueron recogidas para cada horizonte de cada perfil. Para el análisis de macroelementos y elementos traza las muestras fueron digeridas usando agua regia y horno microondas. Las concentraciones medias de elementos traza (mg kg-1) obtenidas en horizontes superficiales fueron: As 15,8, Cd 0,42, Co 9,6, Cr 57,3, Cu 18,7, Mn 467,1, Ni 29,3, Pb 18,7, Zn 53,9. Los resultados obtenidos del análisis estadístico revelan correlaciones significativas entre la mayoría de elementos y el contenido de CCE, arcillas y materia orgánica, indicando que las concentraciones de estos elementos se encuentran controladas por las características del suelo. La concentración de elementos traza es relativamente baja en áreas con elevado contenido de CCE, así la concentración de carbonatos en el suelo es un factor determinante en la presencia y distribución de elementos traza en los suelos del área estudiada. Con respecto a la profundidad, se observa un incremento del contenido de arcillas y pH al aumentar ésta y una disminución de la materia orgánica. Respecto los elementos traza, el Cu, Pb Cd, Mn y Zn presentan una disminución en función de la profundidad, mientras que el As, Co, Cr i Ni no presentan diferencias significativas entre los horizontes comparados. Por lo que se refiere a los suelos desarrollados en cada grupo de referencia se encontraron claras diferencias: sobre calcáreas, los suelos poco desarrollados presentan las concentraciones más bajas de elementos traza, mientras que los suelos diferenciados presentan las mayores concentraciones. En orden ascendente de concentración, el menor contenido corresponde a Arenosols de sistemas dunares litorales, seguidos por los Cambisols sobre margas, Calcisols, Cambisols sobre margas y, finalmente, Luvisols como la tipología más diferenciada y con el mayor contenido de elementos traza. Por otro lado, en suelos desarrollados sobre rocas olivínicas del Keuper aparecen altos contenidos de P, Fe, Co, Cr, Mn y Ni y bajas concentraciones de Cd. Por último se estableció la concentración de niveles de fondo y de referencia. Los valores de referencia obtenidos a partir de gráficos de probabilidad fueron(mgkg): As 28,2, Cd 0,74, Co 16,9, Cr 95,3, Cu 32,6, Mn 793,5, Ni 49,6, Pb 34,7, Zn 96,4.
[eng] In this work, 508 soil profiles of Balearic Islands (European Mediterranean region) were investigated, and the variability in the levels of major elements (Ca, Mg, Al, Fe, K, Na i P), trace elements (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) and some soil properties (sands, silts, clays, calcium carbonate equivalent -CCE-, organic carbon, pH and cation exhange capacity) was examined. Sampling sites with minimal antrhropogenic influence were selected and soil profile samples were analysed for major and trace element content. The soil samples were collected from every horizon in each profile and the samples were digested using aqua regia and microwave oven for pseudo-total trace elements. The median concentrations of trace elements (mg kg-1) obtained in surface horizons were: As 15.8, Cd 0.42, Co 9.6, Cr 57.3, Cu 18.7, Mn 467.1, Ni 29.3, Pb 18.7, Zn 53.9. The results obtained from the statistical analysis reveal significant correlations between most elements and CCE, clay and organic matter contents, indicating that metal concentrations are controlled by soil composition. The trace element concentration is relatively low in areas of high CCE, therefore carbonate concentration in soil is the determining factor in the presence and distribution of trace elements in the soils of the studied area. According to depth, Cu, Pb, Cd, Mn and Zn show an increase with depth, in the same way of clays and pH. As, Co, Cr and Ni do not show statistical differencies between horizons. A clear distinction was found between the metal content of the soils developed in each Reference Soil Group: Over limestones, poor-developed soils show the lowest concentrations of trace elements while well-developed soils have the highest concentrations. In ascending order of concentration, the lowest content correspond to Arenosols of litoral dune systems, followed by Cambisols over marls, Calcisols, Cambisols over marls and, finally, Luvisols as most differenciated tipologies and with higher trace element contents. On the other hand, over Keuper olivinic rocks soils with high concentrations of P, Fe, Co, Cr, Mn and Ni and low concentrations of Cd are developed. The background concentration and reference values have also been stablished. The reference values obtained in this study through probability plots were (mgkg): As 28.2, Cd 0.74, Co 16.9, Cr 95.3, Cu 32.6, Mn 793.5, Ni 49.6, Pb 34.7, Zn 96.4.

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Danielsson, Joakim, and Björkman Emilie. "Kan digitala hjälpmedel användas förmer ståndortsanpassade föryngringar?" Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-85578.

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The aim of this study was to investigate if SI from HPR-data from harvesters and soil moisture classes from digital depth to water maps could be used to support site adaption of regenerations within stands. The study was made on pine and spruce stands in central Sweden. The number of plants/ha, plant height, growth and damage were measured at plot level and for these plots also soil moisture classes and SI were derived from digital maps and HPR. The study shows a potential using SI from HPR and depth to water maps for site adaption of regenerations and to vary tree species within stands. Variations of SI and soil moisture are important within stands regarding different tree species establishment, growth and damage. But also, for sites with medium SI were the choice between pine and spruce is not obvious and in stands with a high spread in SI.

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Bauman, David. "Analyses spatialement explicites des mécanismes de structuration des communautés d'arbres." Doctoral thesis, Universite Libre de Bruxelles, 2018. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/276814.

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La compréhension des processus écologiques qui sous-tendent l’assemblage des communautés végétales et la coexistence des espèces est un objectif central en écologie. Ces processus sont potentiellement nombreux et de natures contrastées. Ainsi, la composition d’une communauté de plantes dépend de processus déterministes liés aux conditions environnementales abiotiques (climat, conditions physiques et chimiques du sol, lumière) et d’interactions biotiques complexes, positives (facilitation, symbioses) comme négatives (compétition, prédation, pathogènes). En outre, les communautés sont influencées par des processus stochastiques (capacité de dispersion limitée, dérive écologique). Si les mécanismes à l’origine de ces processus sont très différents, ils ont néanmoins en commun la génération de motifs (patterns) spatiaux de distribution d’espèces dans les communautés. L’analyse de la structure spatiale des communautés permet ainsi une étude indirecte des processus régissant les communautés. La nature complexe de ces patterns spatiaux a mené au développement de nombreuses méthodes statistiques de détection et de description de patterns. Les méthodes basées sur des vecteurs propres spatiaux sont parmi les plus puissantes et précises pour détecter des patterns complexes et multi-échelles. Ces vecteurs propres, utilisés comme prédicteurs spatiaux, peuvent être combinés à un ensemble de variables environnementales dans un cadre de partition de variation. Celui-ci permet, en théorie, de démêler les effets uniques et l’effet conjoint des variables environnementales et spatiales sur la variation de composition d’une communauté. Il mène ainsi à une quantification de l’action des processus déterministes et des processus stochastiques sur l’assemblage de la communauté. Néanmoins, je montre dans cette thèse qu’un certain flou méthodologique concernant deux étapes déterminantes des analyses basées sur les vecteurs propres spatiaux a mené une proportion élevée d’études à utiliser ces méthodes de manière sous-optimale, voire fortement biaisée. Ceci compromet la fiabilité des patterns spatiaux détectés et des processus écologiques inférés. Une autre limitation de ce cadre d’analyse concerne la fraction de la partition de variation décrivant l’effet environnemental spatialement structurés qu’aucune méthode ne permet de tester.Cette thèse présente des solutions non biaisées, puissantes et précises à ces différentes limitations méthodologiques et permet d’élargir le cadre de l’inférence de processus écologique à partir de patterns spatiaux de communautés. Les différentes étapes d’amélioration de ces méthodes ont également été illustrées dans la thèse au travers de trois cas d’études fournis par deux communautés d’arbres tropicale et tempérée et une communauté de champignons symbiotiques des arbres.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Winter, Daniel. "Resistência, rigidez e durabilidade de solos arenosos estabilizados com materiais mais sustentáveis." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/174398.

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Com uma necessidade cada vez maior da utilização de materiais mais sustentáveis na construção civil, existe uma grande busca por novas substâncias que possam suprir as nossas necessidades de maneira mais “limpa”. O presente trabalho tem como foco propor uma metodologia de dosagem para a obtenção de solos artificialmente cimentados, com determinadas resistências e rigidezes, de maneira que eles sejam duráveis, com a adição de diferentes resíduos. O solo inicialmente estudado é a areia de Osório e os resíduos são a cal de carbureto e o pó de vidro. A cal de carbureto consiste basicamente de hidróxido de cálcio e o pó de vidro de sílica em estado amorfo, gerando assim uma combinação adequada para a ocorrência das reações pozolânicas. A metodologia de dosagem proposta relaciona as propriedades dos materiais com o fator η/Biv0,28, aos sete dias de cura, sendo η a porosidade do solo artificialmente cimentado e, Biv o teor volumétrico de agente cimentante no interior do mesmo (neste caso pó de vidro e cal de carbureto). O expoente externo 0,28 se assemelha ao encontrado em outras metodologias de dosagem para solos artificialmente cimentados com cimento Portland Com a finalidade de validar a metodologia proposta, para condições distintas das analisadas, foram executados ensaios com diferentes períodos de cura (180 dias), diferentes resíduos (cinza de casca de arroz) e um solo distinto (arenito Botucatu), chegando também a correlações do comportamento mecânico destes materiais com o fator η/Biv0,28. Os dados obtidos nesta pesquisa foram comparados com os resultados de outros pesquisadores que utilizaram cal com cinza volante de usinas de carvão juntamente com cal hidratada e de outros trabalhos que utilizaram cimento Portland, todos para criar solos artificialmente cimentados, e, mais uma vez, a metodologia proposta se mostrou eficaz. Foi possível ainda normalizar em função de um valor médio todos os resultados de rigidez, resistência e durabilidade obtendo assim equações únicas em função de η/Biv0,28 para todos os materiais analisados, chegando a uma correlação com mais de 1000 pontos no caso da resistência.
With a growing need for the use of more sustainable materials in construction, there is a great search for new substances that can meet our needs in a "cleaner" way. The present work aims to propose a dosing methodology for obtaining artificially cemented soils, with certain strengths and stiffness, so that they are durable, with the addition of different residues. The initially studied soil is the Osório sand and the residues are carbide lime and glass powder. The carbide lime basically consists of calcium hydroxide and the glass powder consists of silica in the amorphous state, thus generating a great combination for the occurrence of the pozolanic reactions. The proposed dosage methodology relates the properties of the materials with the factor η/Biv0.28, at the seven days of curing, in which η is the porosity of the artificially cemented soil and Biv is the volumetric content of the cementitious agent inside it (in this case powder glass and carbide lime) The external exponent 0.28 resembles that found in other dosing methodologies for artificially cemented soils with Portland cement. The methodology led to a unique correlation for all the dosages used. To validate the hypothesis which was raised, tests were carried out with different curing periods (180 days), different residues (rice husk ash) and a different soil (Botucatu sandstone), reaching optimum correlations. The data obtained in this research were compared with the results of other researchers who used lime with fly ash from coal plants together with hydrated lime and from other works that used Portland cement, all to create artificially cemented soils, and, once again, the proposed methodology proved to be excellent. It was also possible to normalize all the results of stiffness, strength and durability thus obtaining unique equations as a function of η/Biv0.28 for all materials analyzed, reaching a correlation with more than 1000 points.

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Bhattacharyya, Ranjan. "Using palm-mat geotextiles for soil conservation on arable loamy sands in the United Kingdom." Thesis, University of Wolverhampton, 2009. http://hdl.handle.net/2436/88536.

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To date, most studies on the effectiveness of geotextiles on soil erosion rates were conducted in laboratory experiments for <1 h. Hence, at Hilton, East Shropshire, UK, this study investigated the effectiveness of palm-mat geotextiles (Borassus and Buriti mats) in reducing rainsplash erosion, runoff and soil loss and changing selected soil properties under field conditions over two years (January 2007-January 2009). Mat-cover effects on rainsplash erosion were studied in two sets on a loamy sand soil (0o slope). In both sets, six randomly-selected plots (each 1 m2) were completely matcovered and six were bare. Unlike Buriti mats, Borassus mat-cover on bare soil significantly (P<0.001) decreased rainsplash erosion (by ~89%). Duplicate runoff plots (10 x 1 m on a 15o slope) had five treatments (bare, permanent grass, Borassus completely-cover, Borassus buffer strip and Buriti buffer strip). Using Borassus buffer strips (area coverage ~10%) on bare soil decreased runoff by ~71% (P>0.05) and soil erosion by ~92% (P<0.001). Borassus buffer strip, Buriti buffer strip and Borassus completely-covered plots had similar effects in decreasing runoff and soil loss. However, the longevity of Borassus mats was ~twice that of Buriti mats. Despite physical protection, runoff control and sediment entrapment, biomat buffer zones may considerably alter and protect flow direction by presenting barriers and creating several cross-drains. Except Borassus completely-covered plots, all plots had significant (P<0.05) increases in topsoil (0-5 cm) bulk density and decreased aggregate stability. However, buffer strips were more effective in trapping fine particles than Borassus completely-covered plots. No treatments had significant (P>0.05) effects on changes in pH, soil organic matter, total soil carbon or N. Plots with Borassus mats significantly (P<0.05) increased total P and decreased total Ca. Treatments had no significant effects on changes in total S, Mg, Zn, Cu, Fe, Mn, Mo or Cl concentrations. Borassus buffer strips can effectively conserve soil and water and improve and maintain selected soil properties, with results similar to Borassus completely-covered plots. The mechanisms explaining the effectiveness of buffer zones require further studies under varied pedo-climatic conditions.

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Pontelli, Charles Bolson. "CARACTERIZAÇÃO DA VARIABILIDADE ESPACIAL DAS CARACTERÍSTICAS QUÍMICAS DO SOLO E DA PRODUTIVIDADE DAS CULTURAS, UTILIZANDO AS FERRAMENTAS DA AGRICULTURA DE PRECISÃO." Universidade Federal de Santa Maria, 2006. http://repositorio.ufsm.br/handle/1/7543.

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In this work were investigated the spatial variability existent on the soil attributes utilized for soil fertility evaluation and its grade of participation on the yield crop variability. An experiment was conducted over five years (2000 to 2005) in an area of 57 ha in the municipality of Palmeira das Missões in a Latossolo Vermelho distrófico típico (EMBRAPA, 1999). Geopositioned soil samples were collected in May 2002, with a regular grid of 100x100 meters and at a depth of 0 to 10 cm. Yield data of soybean 2000/01, corn 2001/02, wheat 2002, soybean 2002/03, wheat 2003, soybean 2003/04 and corn 2004/05 were analyzed. The yield data was collected with a machine equipped with a system that take and register georeferenced data. Yield averages for each soil sample point were calculated, using yield data collected at a radius of 30 meters around the point. The yield and soil data were analyzed using the Pearson correlation Matrix. Average quadratic polynomial equations were calculated for the yields of soybean 2001/02 and 2003/03, where the nutrient pH, Organic Mater (OM), Phosphorus (P) and yield average were divided into five categories: very low (VL), low (L), mean (M), high (H) and very high (VH). For P was used categories proposed by Schlindwein (2003), for pH and OM are used categories adapted from Comissão (2004). Maximum efficiency technical (MET) and maximum economical efficiency (MEE)considering 90% of relative yield are calculated using the adjusted equations. A small correlation was found between the soil chemical attributes and the yield productivity. A negative correlation from 0,25 to 0,46 was found between the clay texture and corn yield 2005 and soybean yield 2004 respectively. The average soybean yield response to soil attributes curves shows the values of maximum technical efficiency (MTE) of the attributes in the soil. The MTE for P, pH and OM are 14,4 mg dm-3; 5.9 and 4.1%, respectively. Higher values of MTE can reduce the crop yield. The MEE for P, pH and OM are 4,4 mg dm -3; 5.5 e 3.2%, respectively.
Neste trabalho foi investigada a variabilidade espacial existente nos atributos do solo utilizados na avaliação da fertilidade dos solos, bem como seu grau de participação na variabilidade da produtividade das culturas. Foi conduzido um experimento por 5 anos (2000 a 2005) em uma área comercial de 57 ha no município de Palmeira das Missões em um Latossolo Vermelho distrófico típico (EMBRAPA, 1999). Em maio de 2002 foram coletadas amostras de solo georeferenciadas em malha regular de 100 x 100 metros a uma profundidade de 0 a 10 cm. As safras de soja 2000/01, milho 2001/02, soja 2002/03, trigo 2003, soja 2003/04 e milho 2004/05 foram analisadas. Os dados de produtividade foram coletados com uma colhedoura com sistema de tomada e registro de informações georeferenciadas. Para cada ponto de coleta de solo foi calculada uma produtividade média utilizando-se os dados num raio de 30 m ao redor do ponto. Os dados de produtividade e solo foram analisadas pela matriz de correlação de Pearson. Para a cultura da soja nas safras de 2000/01 e 2002/03 foram determinadas equações polinomiais quadráticas médias, onde se determinou os valores médios do pH, matéria orgânica (MO), fósforo (P) e da produtividade para cinco classes: muito baixa (MB), baixa (B), média (M), alta (A) e muito alta (MA). Para o fósforo foram adotadas as classes propostas por Schlindwein, (2003) e para pH e MO usou-se classes adaptadas da Comissão (2004). Através das equações ajustadas foi calculado a máxima eficiêcia técnica (MET) e a máxima eficiencia economica MEE) que foi obtida considerando 90 % do rendimento relativo. Os atributos químicos do solo e a produtividade apresentaram baixas correlações. A argila apresentou correlação negativa de 0.25 a 0.46 com as produtividades de milho 2005 e soja 2004 respectivamente. Os valores de MET para P, pH e MO foram de 14,4 mg dm-3; 5,9 e 4,1%, respectivamente. Valores acima destes, podem incorrer em decréscimo de produtividade. A MEE para P, pH e MO foram de 4,4 mg dm-3; 5,5 e 3,2%, respectivamente.

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Federman, Sonia Regina. "Recobrimento de aço inoxidável ABNT 409 empregando filme fino bioativo obtido via sol-gel." Universidade Federal de Minas Gerais, 2007. http://hdl.handle.net/1843/MAPO-7REN7E.

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In the present study, composites made up of ABNT 409 stainless steel was obtained where films produced according to the sol-gel route were deposited using the immersion method. A film of the binary system SiO2-CaO, and another one of the ternary system SiO2-CaOP2O5, were employed. The structure and properties of these films were characterized through the scanning electron microscopy (SEM) technique, coupled with the energy dispersive spectroscopy, atomic force microscopy, Fourier Transformed Infrared spectroscopy (FTIR), Raman spectroscopy, and glow discharge optical emission spectroscopy and thermal analysis. The use of these techniques revealed the formation of a homogeneous sol-gel film, which adhere to the substrate (degree of 0 in the tape test) with no indication of cracks nor pores. After the film densification stage, AFM images showed the presence of calcium nitrate protuberances on the surface of the films. These protuberances made it possible to design the surface area of the film simply by manipulating easily accessed parameters, such as the temperature and duration of the film drying stage. The variation in temperature and duration of the thermal treatment made it possible to obtain surfaces presenting innumerous protuberances as well as surfaces exempt from such protuberances. Since one of the key aims of this work is the utilization of these coatings in the clinical area, the biocompatibility of the films was accessed through two methods: one method using a solution simulated to corporeal fluids and another using cell culture tests. The method using the corporeal solution suggested biocompatibility through the recipitation of a hydroxyapatite precursor (monocalcium phosphate) on the surface of the films. The method of cell cultures also proved the biocompatibility of the films as no toxic effects were detected in any of the samples analyzed. Another important finding was the cell viability index of the sol-gel films, which ranged from 90% to 100%, in comparison with that of the control used.
Nesse trabalho foram obtidos compósitos constituídos de aço inox ABNT 409 onde foram depositados filmes produzidos segundo a rota sol-gel, através do método de imersão. Foram empregados um filme, binário do sistema SiO2-CaO e outro, ternário, do sistema SiO2-CaO-P2O5. Tanto a caracterização estrutural quanto à das propriedades desses filmes se deu através das técnicas de microscopia eletrônica de varredura acoplada ao espectrômetro dispersivo de energia, microscópio de força atômica, espectroscopia na região do infravermelho por Transformada de Fourier, Raman e espectroscopia de centelhamento e análise térmica. A utilização dessas técnicas constatou a formação de um filme sol-gel homogêneo, aderente ao substrato (grau 0 no teste de fita) sem indicativo da presença de trincas e poros. Após a etapa de densificação dos filmes, imagens de AFM constataram a presença de protuberâncias constituídas de nitrato de cálcio na superfície desses filmes. Essas protuberâncias possibilitaram projetar a área superficial do filme, simplesmente manipulando parâmetros de fácil acesso como a temperatura e duração da etapa de secagem dos filmes. A variação da temperatura e duração do tratamento térmico permitiu obter superfícies apresentando inúmeras protuberâncias até superfícies isentas delas. Como um dos objetivos do trabalho é a utilização desses revestimentos na área clínica, a biocompatibilidade dos filmes foi acessada através de dois métodos: o da solução similar ao fluido corpóreo e do ensaio de cultura de células. O método utilizando a solução corpórea sugeriu a biocompatibilidade através da precipitação de um precursor da hidroxiapatita (fosfato monocálcico) na superfície dos filmes. O método de cultura de células, por sua vez, comprovou a biocompatibilidade dos filmes, uma vez que, em nenhuma das amostras analisadas foi detectado qualquer efeito tóxico. Uma outra informação importante foi o índice de viabilidade celular dos filmes sol-gel encontrado na faixa de 90% a 100% em relação ao controle utilizado.

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Muir, Autumn M. "The Psalter Mappaemundi: Medieval Maps Enabling Ascension of the Soul within Christian Devotional Practices." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1300733958.

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Reis, Emmerson Moises. "Síntese e caracterização de híbridos porosos à base de sílica e quitosana obtidos através do processo sol-gel para aplicação em engenharia de tecidos." Universidade Federal de Minas Gerais, 2007. http://hdl.handle.net/1843/MAPO-7REJMN.

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The fabrication of biomaterials based on inorganic and organic species combined at a nanoscale level has increased in the last years due to their varied characteristics and application possibilities. Chitosan is a natural polysaccharide and has attracted much interest because of their non-toxicity, biodegradability, biocompatibility, bacteriostatic properties. Since chitosan has two hydroxyl groups and one amino group per glucoseamine unit, new chitosan derivatives and interactions with other materials can be produced. On the other hand,silica based bioactive glasses have been widely studied since they have the capacity to promote bone-tissue formation at their surface. In this work the sol-gel method was used for preparation of macroporous 3D hybrid scaffolds based on silica and chitosan in various compositions (10, 20 and 30% wt). The results showed that porous hybrids were successfully synthesized by the sol-gel method at low temperature. The drying methods using oven at 50oC and low vacuum were suitable to obtain dry and intact hybrid foams. The use of 10 and 20% of chitosan in weight to produce the hybrids resulted in macroporous scaffolds with larger pore size range (100-500µm). The hybrids H30 showed pore sizes from 50 to 250µm. The estimated porosity by Archimedes method was around 90%, 86% and 78% for hybrids H10,H20 and H30, respectively. XRD patterns of the samples showed the amorphous character of the hybrids, while chitosan, a semi-crystalline polymer, was characterized by a clear peak at 2 equal 200. The mechanical behavior of the hybrids was evaluated in compression and showed higher strength than silica glasses. The FTIR spectroscopy showed a band relative to Si-O-C bond that was also found to increase with the increasing the amounts of chitosan in the hybrid. This fact can suggest an interaction between the organic-inorganic phases in the material. The cytotoxicity evaluation exhibited successful viability of osteoblasts and the hybrids presents in the culture does not interfered with alkaline phosphatase production, confirming the low toxicity level of the hybrids prepared, despite the collagen secretion was decreased in the presence of the samples when compared to control group.
A produção de híbridos organo-inorgânicos sintetizados em escala nanométrica tem crescido nos últimos tempos devido às suas propriedades favoráveis e às varias possibilidades de aplicação na engenharia de tecidos. A quitosana é um polissacarídeo natural caracterizado pela baixa toxicidade, biodegradabilidade, biocompatibilidade e por suas propriedades bacteriostáticas. Tendo em vista que a quitosana possui dois grupos hidroxilas e um grupo amina por unidade de glucosamina, derivados de quitosana e interações com outros materiais podem ser obtidos. Estudos na literatura têm associado aos vidros bioativos baseados na sílica a capacidade de formar uma forte ligação superficial com o tecido ósseo. Neste trabalho, o processo sol-gel foi utilizado para a síntese de matrizes híbridas macroporosas compostas por sílica e quitosana em várias proporções (10, 20 e 30% em peso). Os resultados mostraram que a produção dos híbridos foi satisfatória através do método sol-gel. A utilização da quitosana numa proporção de 10 e 20% resultou em matrizes macroporosas com ampla distribuição de tamanho de poros (100 a 500m). Os híbridos com 30% de quitosana apresentaram distribuição de poros de 50 a 150m. As porosidades obtidas através do método da balança de Arquimedes foram 90%, 86% e 78% para os híbridos H10, H20 e H30, respectivamente. A análise por difração de raios-X mostrou o caráter amorfo dos híbridos sintetizados, enquanto que a quitosana foi caracterizada por um pico cristalino a 200 em 2?. O comportamento mecânico dos híbridos foi avaliado através do ensaio de compressão e os resultados mostraram valores de tensão máxima à fratura significativamente superiores aos apresentados pelos vidros puros. A espectroscopia por infravermelho mostrou bandas relativas aos componentes envolvidos na síntese e um banda associada ao grupamento Si-O-C que se tornou mais acentuada à medida que a quantidade de quitosana aumentou no híbrido, o que poderia sugerir uma interação entre as fases orgânicas e inorgânicas presentes nos híbridos. Os testes de citotoxicidade realizados com osteoblastos mostraram adequadas viabilidade celular e produção de fosfatase alcalina, confirmando os baixos níveis de toxicidade apresentados pelos híbridos sintetizados, apesar da baixa produção de colágeno quando comparados com o grupo controle.

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Edwards, Michael. "Characterization of Fillite as a Planetary Soil Simulant in Support of Rover Mobility Assessment in High-Sinkage/High-Slip Environments." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/292.

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This thesis presents the results of a research program characterizing a soil simulant called Fillite, which is composed of alumino-silicate hollow microspheres harvested from the pulverized fuel ash of coal-fired power plants. Fillite is available in large quantities at a reasonable cost and it is chemically inert. Fillite has been selected by the National Aeronautics and Space Administration (NASA) Glenn Research Center to simulate high-sinkage/high-slip environment in a large test bed such as the ones encountered by the Spirit rover on Mars in 2009 when it became entrapped in a pocket of soft, loose regolith on Mars. The terms high-sinkage and high-slip used here describe the interaction of soils with typical rover wheels. High-sinkage refers to a wheel sinking with little to no applied force while high-slip refers to a spinning wheel with minimal traction. Standard material properties (density, specific gravity, compression index, Young's modulus, and Poisson's ratio) of Fillite were determined from a series of laboratory tests conducted in general accordance with ASTM standards. Tests were also performed to determine some less standard material properties of Fillite such as the small strain shear wave velocity, maximum shear modulus, and several pressure-sinkage parameters for use in pressure-sinkage models. The experiments include an extensive series of triaxial compression tests, bender element tests, and normal and shear bevameter tests. The unit weight of Fillite on Earth ranges between 3.9 and 4.8 kN/m3, which is similar to that of Martian regolith (about 3.7 - 5.6 kN/m3) on Mars and close to the range of the unit weight of lunar regolith (about 1.4 - 2.9 kN/m3) on the Moon. The data presented here support that Fillite has many physical and mechanical properties that are similar to what is known about Martian regolith. These properties are also comparable to lunar regolith. Fillite is quite dilatant; its peak and critical angles of internal friction are smaller than those of most other simulants. Smaller shear strength, coupled with much smaller bulk unit weight as compared to other simulants, results in smaller bearing and shearing resistances allowing for better simulation of the intended high-sinkage, high-slip behavior for rover mobility studies. The results of the normal bevameter tests were used to determine parameters for two models available in the literature - the Bekker model and the New Model of Mobility (N2M) model. These parameters were then used to predict the sinkage of a Spirit rover wheel if the rover were to be used on Fillite. The predicted sinkage of a Spirit rover wheel in Fillite was 84% of the wheel diameter, which was within the observed sinkage of 50 to 90% of the wheel diameter of the Spirit rover on Mars. Shear bevameter tests were also performed on Fillite to assess the shear stresses and shear deformations imparted by wheels under torsional loads. The results compared well to the estimated shear stresses and deformations of Martian soil caused by the wheels of the Spirit rover. When compared to other simulants (e.g. GRC-1), the pressure-sinkage and shear stress-shear deformation behaviors of Fillite confirm that Fillite is more suitable for high-sinkage and high-slip rover studies than other typical simulants derived from natural terrestrial soils and rocks.

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Santos, Paulo Ricardo Alves dos. "Corn consortium with forage: attributes physical soil and productivity." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17324.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
The intensification of agricultural production systems is increasing in the current agriculture. In this sense, the simultaneous planting forage to grain crops, constitutes an alternative in the intensification of the production system, which can increase or not the productivity of the main crop, and produce straw for mulching. In order to check the occurrence of changes in the physical properties of the soil and in corn yield and dry matter production due to the corn consortium / forage in two sowing dates, this study was conducted in the experimental area of the Department of Agricultural Engineering of the Federal University of CearÃ. The design was used in a randomized block design in a factorial scheme (3x2) + 1 with four replications, totaling 28 experimental units. The treatments consisted of three forages: Brachiaria, Panicum maximum cv. MombaÃa and Crotalaria spectabilis intercropped with maize in two of fodder sowing dates, between the lines of simultaneous sowing maize (season 1 - E1) and corn leading the V4 stage of corn (season 2 - E2), and the control. The results showed that intercropping maize / forage did not interfere in phytotechnical characteristics of corn, nor in productivity, however produced changes in soil physical properties when the day of sowing in season 1. Despite the changes that have occurred in the soil, they were not sufficient to enhance the productivity of maize, which could possibly be related assessments on only one crop cycle. But when the goal was the production of dry straw, it is concluded that fodder Brachiaria brizantha and Mombasa at the time 1 (E1) are recommended
A intensificaÃÃo dos sistemas de produÃÃo agrÃcola Ã cada vez maior na atual agricultura. Nesse sentido, o plantio simultÃneo de forrageiras com culturas produtoras de grÃos, constitui em uma alternativa na intensificaÃÃo do sistema de produÃÃo, que poderÃ incrementar ou nÃo a produtividade da cultura principal, alÃm de produzir palha para cobertura do solo. Com o objetivo de verificar a ocorrÃncia de mudanÃas nas propriedades fÃsicas do solo, bem como na produtividade do milho e produÃÃo de matÃria seca em funÃÃo do consÃrcio milho/forrageiras em duas Ãpocas de semeadura, o presente trabalho foi conduzido na Ãrea experimental do Departamento de Engenharia AgrÃcola da Universidade Federal do CearÃ. Foi utilizado o delineamento em blocos ao acaso, no esquema fatorial (3x2) + 1 com quatro repetiÃÃes, totalizando 28 unidades experimentais. Os tratamentos foram constituÃdos por trÃs forrageiras: Brachiaria brizantha, Panicum maximum cv. MombaÃa e CrotalÃria spectabilis consorciadas com o milho em duas Ãpocas de semeadura das forrageiras, na entrelinha do milho simultÃneo a semeadura (Ãpoca 1 â E1) e na entrelinha do milho no estÃdio V4 do milho (Ãpoca 2 â E2), alÃm da testemunha. Os resultados permitiram concluir que a consorciaÃÃo milho/forrageiras nÃo interferiram nas caracterÃsticas fitotÃcnicas do milho, nem tampouco, na produtividade, porÃm proporcionaram modificaÃÃes nas propriedades fÃsicas do solo quando da realizaÃÃo da semeadura na Ãpoca 1. Apesar das modificaÃÃes ocorridas no solo, as mesmas nÃo foram suficientes em incrementar a produtividade do milho, o que possivelmente pode estar relacionado as avaliaÃÃes em apenas um ciclo da cultura. JÃ quando o objetivo foi a produÃÃo de matÃria seca de palha, conclui-se que as forrageiras Brachiaria Brizantha e MombaÃa na Ãpoca 1 (E1) sÃo recomendadas

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31

Ouattara, Korodjouma. "Improved soil and water conservatory managements for cotton-maize rotation system in the western cotton area of Burkina Faso /." Umeå : Dept. of Forest Ecology and Management, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200754.pdf.

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32

Claverie, Etienne. "Modélisation de la température du sol avec un bilan d’énergie, application à la prédiction de l’émergence du maïs (Zea mais)." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLC028/document.

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La croissance en début de cycle des grandes cultures est principalement influencée par la température et la teneur en eau du sol. Nous avons développé un modèle capable de prédire ces variables grâce à l’utilisation de données climatiques largement disponibles. Des analyses de la sensibilité du modèle nous ont permis d’identifier les composants qui contribuent à son incertitude. Après calibration, une erreur moyenne relative de moins de 10 % est constatée pour la température et la teneur en eau à 30 cm de profondeur.Dans des conditions de semis standard en Suisse, l’émergence du maïs a été mieux prédite en utilisant notre température de sol simulée plutôt que la température de l’air, plus couramment utilisée. Ce travail est une application d’un modèle biophysique complexe à un problème agronomique. Les résultats participeront à l’optimisation de l’effort de sélection des variétés tolérantes au froid. Deux pistes de recherche peuvent être considérées pour des futurs travaux: une meilleure modélisation de l’évaporation et une décomposition de l’émergence
The beginning of crop growth is influenced by soil temperature and water content near the surface. We have developed a model that predicts the local temperature and water content surrounding the seed using easily available meteorological data. Our global sensitivity analysis helped us identify the components of the model with the largest contribution to the output uncertainty. After calibration, the model showed less than 10 % relative error for temperature and water content at 30 cm. In standard sowing conditions in north-western Switzerland, the emergence was better predicted when using our simulated seed bed temperature than air temperature, the classical proxy variable. Combining the emergence model with soil temperature simulation, an accurate prediction of emergence was achieved. This work is an example of applying complex biophysics model for understanding an agronomic problem. The results of this work will participate in optimising breeding efforts for cold-tolerant crop varieties. Future investigations should consider a finer modelling of processes for evaporation and emergence

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Herbst, Mark Alan. "Impact of Mass Mixing on the Lateral Resistance of Driven-Pile Foundations." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2353.pdf.

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Barron, Jennie. "Dry spell mitigation to upgrade semi-arid rainfed agriculture : Water harvesting and soil nutrient management for smallholder maize cultivation in Machakos, Kenya." Doctoral thesis, Stockholm : Institutionen för systemekologi, Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-98.

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35

Smith, Peter Hollingsworth. "Water at the Phoenix landing site." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194791.

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The Phoenix mission investigated patterned ground and climate in the northern arctic region of Mars for 5 months starting May 25, 2008. A shallow ice table was uncovered by the robotic arm in a nearby polygon's edge and center at depths of 5-15 cm. In late summer snowfall and frost blanket the surface at night; water ice and vapor constantly interact with the soil. Analysis reveals an alkaline Ph with CaCO3, aqueous minerals, and salts making up several wt% of the soil; liquid water is implicated as having been important in creating these components. In combination with the oxidant perchlorate (~1 wt%), an energy source for terrestrial microbes, and a prior epoch of higher temperatures and humidity, this region may have been a habitable zone.

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Dutton, Anona L. "Process-based simulations of near-surface hydrologic response for a forested upland catchment: the impact of a road /." May be available electronically:, 2000. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.

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37

Shorts, Daniel Calvert. "Impact Characterization of Earth Entry Vehicle for Terminal Landing (on Soil)." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/87727.

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In order to more accurately predict loads subjected to the EEV (Earth Entry Vehicle) upon impact with a variety of materials, finite element simulations of soil/EEV impact were created using the program LS-DYNA. Various modeling techniques were analyzed for accuracy through comparison with physical test data when available. Through variation of numerical methods, mesh density, and material definition, an accurate and numerically efficient representation of physical data has been created. The numerical methods, Lagrangian, arbitrary Lagrangian-Eulerian (ALE), and spherical particle hydrodynamics (SPH) are compared to determine their relative accuracy in modeling soil deformation and EEV acceleration. Experimentally validated soil material parameters and element formulations were then used in parametric studies to gain a perspective on effects of EEV mass and geometry on its maximum acceleration across varying soil moisture content. Additionally, the effects of EEV orientation, velocity, and impact material were explored. Multi-material arbitrary Lagrangian-Eulerian (MMALE) formulation possess the most effective compromise between its ability to: accurately display qualitative soil behavior, accurately recreate empirical test data, be easily utilized in parametric studies, and to maintain simulation stability. EEV acceleration can be minimized through increase of EEV mass (with constant geometry), allowing for maximum penetration depth, and longest deceleration time. A critical orientation was discovered at 30⁰ from normal, such that maximum EEV surface area impacts the soil surface instantaneously, resulting in maximum acceleration. Off-nominal impact with concrete is predicted to increase acceleration by up to 630% from impact with soil.
MS

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Israelsson, Filip. "Sustainable mass handling : Modelling quantities of excavated soil and rock in residential construction projects." Thesis, KTH, Kraft- och värmeteknologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-146225.

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An efficient handling process of aggregates and excavated soil and rock will be of increasing importance in expanding urban regions. The construction of residences, infrastructure and commercial areas generate significant amounts of soil and rock that can be re-used more efficiently as construction material, minimizing transportation and environmental impact. A key element is the implementation of central intermediate storage sites for re-use purposes and cooperation between several construction projects in a region. The evaluation of storage capacities and optimal site locations is in turn dependent on comprehensive knowledge about what quantities of aggregates and excavated soil and rock that will be generated and utilized in the region. The calculation model presented in this thesis provides a way of estimating the amount of excavated soil and rock generated during the construction of new residential areas at an initial stage of the planning process. The excavated volume is expressed as a function of the number of residents and the number of floors in the buildings of the planned area, allowing for an early estimation that may effectively influence the logistical planning of the mass handling process. The simplified calculation model applied to a case study of the existing residential area Annedal in Stockholm produces an estimated amount of 577 500 ton excavated soil and rock, approximately 3.8 % lower than the reference value of 600 000 ton. Regional storage sites are advantageous as different construction projects generate and utilize different types of soil, rock and aggregates, resulting in a higher possible re-use share than in individual projects. When regarding the energy usage in transportation, it is shown that intermediate storage sites located within 10 km of the construction site may allow for more than 15 % energy reduction if re-using 25 % of the excavated amount of soil and rock. A distance of 5 km may yield more than 20 % reduction of transportation energy for the same share of re-use.

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Filho, Osmar Bazaglia. "Comparação entre mapas de solos obtidos pelos métodos convencional e digital numa área complexa." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-24042012-102912/.

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Mapas de solos são essenciais para o desenvolvimento de áreas agrícolas de maneira economicamente viável e ambientalmente correta. Até o momento, o Brasil conta apenas com mapas de solos de escala pequena (1:250.000 a 1:1.000.000), cuja utilização é limitada para planejamento agrícola e ambiental a nível de propriedade rural. Apesar de sua importância, no Brasil poucos mapeamentos têm sido realizados pelos órgãos públicos competentes, principalmente por restrições orçamentárias e falta de pedólogos. Além disso, o 5º e 6º níveis categóricos do Sistema Brasileiro de Classificação de Solos (SiBCS), que devem ser utilizados em levantamentos detalhados, não estão definidos. Dessa forma, pouco se sabe a respeito da qualidade/similaridade dos mapas desse nível que vem sendo executados no país. Os principais motivos para essa situação são: elevado custo, mão-de-obra e tempo requeridos nos trabalhos de mapeamento. Uma alternativa para redução desses entraves é o mapeamento digital de solos (MDS). Sendo assim, objetivou-se: (i) comparar quatro mapas de solos convencionais de uma mesma área complexa, de mesma escala (1:10.000), elaborados por diferentes pedólogos de maneira independente, e (ii) comparar estes com um mapa de solos obtido por técnica de MDS. Para tanto, utilizou-se uma área de estudo de 182 ha, cultivada com cana-de-açúcar, localizada no município de Rafard (SP). Foram fornecidas aos pedólogos as mesmas informações: mapas geológico e pedológico semidetalhado (ambos escala 1:100.000), mapa planialtimétrico e fotografias aéreas (ambos escala 1:10.000). Viagens a campo, resultados de análise e exame de perfis foram realizados conforme estes julgaram necessário. Para o mapa digital de solos foram utilizados atributos de terreno (elevação, declividade, poder de fluxo dágua, fator LS, plano e perfil de curvatura), calculados a partir do modelo digital de elevação gerado com base no mapa planialtimétrico, e informação espectral superficial do solo de uma imagem de satélite Landsat 5 (sensor TM) obtida em período que a superfície do solo estava desnuda. Tais informações foram sintetizadas através da análise por componentes principais, sendo posteriormente feita uma compartimentação da área com auxílio da análise Fuzzy K-médias. Nos compartimentos foram realizadas observações para classificá-los como unidades de mapeamento. Os mapas foram então comparados dois a dois, sendo medida a correspondência espacial para cada um dos quatro níveis categóricos estabelecidos no SiBCS, e além destes acrescida a informação textural. Tanto para as comparações entre mapas convencionais, quanto para comparações com o mapa digital, houve redução da correspondência espacial para os níveis categóricos mais detalhados. A maior correspondência final (4º nível + textura) entre mapas convencionais se deu entre os mapas A e B (24,3 %). As maiores correspondências espaciais em relação ao mapa digital se deram entre este e o mapa A (35,2 %) e o mapa B (28,7 %). Portanto confirma-se que os mapas de solos convencionais variam conforme critérios subjetivos do executor, cuja mensuração é impraticável. O mapa de solos digital gerado pela metodologia proposta obteve índices de correspondência aos mapas convencionais semelhantes aos obtidos entre estes, sendo uma boa opção no processo de otimização dos trabalhos de mapeamento.
Soil maps are essential for the development of agricultural areas in an economically viable and environmentally friendly manner. So far, Brazil only has soil maps of small scale (1:250,000 to 1:1,000,000), whose use is limited to agricultural and environmental planning at the farm. Despite its importance, in Brazil a few mappings have been carried out by public authorities, primarily because budget constraints and lack of soil scientists. In addition, 5 and 6 categorical levels of the Brazilian System of Soil Classification (SiBCS), which should be used for detailed surveys, are not defined. Thus, little is known about the quality and level of similarity of the maps that have been undertaken in the country. The main reasons for this situation are: high cost, manpower and time required of mapping. An alternative to reducing these barriers is the digital soil mapping (DSM). Therefore, the objectives were to: (i) compare four conventional soil maps of the same complex area of the same scale (1:10,000), prepared by different independent soil scientists independently, and (ii) compare these with a soil map obtained by the DSM technique. For this purpose, we used a study area of 182 ha cultivated with sugar cane in the municipality of Rafard (SP). The same information was provided to the soil scientists: a geological map anda a semi-detailed pedological map (both scale 1:100,000), planialtimetric map and aerial photographs (both scale 1:10,000). Field trips, results of analysis and examination soil profiles were performed as deemed necessary. The information for the digital soil map included terrain attributes (elevation, slope, stream power, LS factor, plan and profile curvature), calculated from the digital elevation model generated based on the topographic map, and data reflectance of the surface soil of a satellite image Landsat 5 (TM sensor) obtained in the period that ground was bare. Such information has been summarized by principal component analysis, and subsequently made a subdivision of the area using Fuzzy K-means analysis. Observations were made in each compartment to classify them as a mapping unit. The maps were then compared two by two, the spatial correspondence being measured for each of the four levels established in the Brazilian System of Soil Classification, and beyond the increased textural information. Both for comparisons between conventional maps, and for comparisons to the digital map, there was a reduction of spatial correspondence to the more detailed categoric levels. The longest match final (4th level + texture) occurred between conventional maps A and B (24.3%). The highest spatial correlation in relation to the digital map that occurred was between it and the map A (35.2%) and the map B (28.7%). Therefore it is confirmed that the conventional soil maps vary according to subjective criteria of the soil scientist, whose measurement is impractical. The digital soil map generated by the proposed method achieved similar rates of correspondence with the conventional maps as those obtained among these, being a good choice in the optimization process of mapping work.

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Barros, Inácio de. "Soil related limitation to crop production in the semiarid Northeast of Brazil : identification and modeling /." Stuttgart : Inst. für Bodenkunde und Standortslehre, 2002. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=010218120&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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41

Fuhrmann, Andrew. "Effect Of Rainfall Events On The Thermal And Moisture Exposure Of Underground Electric Cables." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/331.

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Cable ampacity analysis is generally performed assuming constant worst-state environmental conditions, which often correspond to a dry soil condition or to a condition with uniform ambient soil moisture content. The characteristic time scale of thermal variation in the soil is large, on the order of several weeks, and is similar to the time scale between rainfall events in many geographic locations. Intermittent rainfall events introduce significant transient fluctuations that influence the thermal conditions and moisture content around a buried cable both by increasing thermal conductivity of the soil and by increasing the moisture exposure of the cable insulation. This paper reports on a computational study of the effect of rainfall events on the thermal and moisture transients surrounding a buried cable. The computations were performed with a finite-difference method using an overset grid approach, with an inner polar grid surrounding the cable and an outer Cartesian grid. The thermal and moisture transients observed in computations with periodic rainfall events were compared to control computations with a steady uniform rainfall. Under periodic rainfall conditions, the temperature and moisture fields are observed to approach a limit-cycle condition in which the cable surface temperature and moisture content oscillate in time, but with mean values that are significantly different than the steady-state values.

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42

Acosta, Juan José Bonnin [UNESP]. "Índice de cone, capacidade de suporte de carga e teor de água de quatro solos da Fazenda Lageado, Botucatu/SP : correlações r mapas de isocompactação." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/101696.

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O presente trabalho objetivou avaliar a ocorrência e distribuição da compactação, bem como a influência temporal do teor de água do solo na sua resistência à penetração medida através do índice de cone (IC), correlacionando-a com o modelo de capacidade de suporte de carga do solo, visando estabelecer um procedimento que permita localizar e visualizar pontos ou zonas compactadas. Os experimentos foram realizado na Fazenda Lageado da UNESP/FCA, Botucatu/SP., sendo selecionados quatro diferentes tipos de solos, sendo: solo 1: LATOSSOLO VERMELHO (LV), textura média, teores de argila entre 15 a 34 %, e elavdo grau de intemperização; solo 2: NEOSSOLO FLÚVICO (RU), oriundo de materiais não consolidados, de deposição recente, desenvolvidos sob releve plano, revelando camadas nitidamente estratificadas, ou seja, extratos granulometricamente muito distintos, podendo aparecer camadas argilosas sobrepostas a camadas arenosas ou vice-versa; solo 3: NITOSSOLO VERMELHO distroférrico, de textura argilosa, com teores de argila superiores a 50 %, manejada em sistema de plantio direto e solo 4: NITOSSOLO VERMELHO distroférrico, de textura argilosa, com teores de argila superiores a 50 %, preservada em pousio por vários anos. Utilizou-se um penetrômetro hidráulico-eletrônico para a amostragem da resistência mecânica do solo à penetração, em 5 épocas diferentes, nas profundidades de 0 a 0,10; 0,10 a 0,20; 0,20 a 0,30; 0,30 a 0,40 m. O teor de água do solo foi monitorado durante a avaliação do IC, nas profundidades de 0 a 0,20 e de 0,20 a 0,40 m. A análise espacial foi realizada através da geoestatística, para a construção do semivariograma e através da técnica de interpolação, construíram-se os mapas de isocompactação do solo. A evidência da relação entre o teor de água do solo e o IC de mapas interpolados nem sempre foi possível...
The aim of this work was to evaluated the soil compaction and its distributions, soil water content influence on the soil resistance measured by the soil cone index (CI), correlating the soil load capacity model in order to establish a procedure able to locate points or zones with soil compaction. The experimental area was at Lageado Experimental Farm, UNESP/FCA, Botucatu/Sao Paulo. Different soil type was used and a hydraulic-electronic penetrometer was used to measure the soil resistance at 0-0.10; 0.10-0.20; 0.20-0.30 and 0.30-0.40 m. During the soil cone index sampling, soil core samples were taken at 0-0.20m and 0.20-0.40m depths in 5 different dates. Geostatistic was used to analyze the spatial variability and semivariograms were done. Using interpolation techniques isocompaction maps were made. The relation between soil water content and soil cone index sometimes was not possible, mainly in place where the soil was extremely wet or extremely dry. Mean soil cone index values and water content value for area 1 were between 1.42 to 8.99 MPa and 9.59 to 17.63%, respectively. On the area 2 the soil cone index was between 0.3 to 5.65 MPa and water content value was between 13.64% to 27.92%. On the area 3 the CI was between 1.58 to 8.17 MPa and water content value was between 17.46% to 31%, and for the area 4 the IC and water content value was 1.16 to 6.24 MPa and 16.76 to 23.49%, respectively. Those results showed a spatial heterogeneity for those parameters. Models of soil load capacity esteem quite well the preconsolidation pressure ( p) in function of soil water content, allowing identifying, in each area, the layer with higher mechanical resistance probably more affected by the traffic and soil tillage. The p could be determined in function of CI and reviewed to be an excellent tool to identify point or zone with soil compaction or with higher mechanical resistance...(Complete abstract, click electronic access below)

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43

Smith, Heather D. "Designing an Instrument Based nn Native Fluorescence to Determine Soil Microbial Content at a Mars Analog Site." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/614.

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For this research project we designed an instrument to detect bacteria via biomolecular fluorescence. We introduce the current understanding of astrobiology, our knowledge of life beyond Earth, and the commonality of Earth life as it pertains to the search for life on Mars. We proposed a novel technique for searching for direct evidence of life on the surface of Mars using fluorescence. We use the arid region of the Mojave Desert as an analog of Mars. Results indicate the fluorescence of the biotic component of desert soils is approximately as strong as the fluorescence of the mineral component. Fluorescence laboratory measurements using the portable instrument reveal microbial concentration in the Mojave Desert soil is 107 bacteria per gram of soil. Soil microbial concentrations over a 50 meter area in the Mojave Desert, determined in situ via fluorescence, show that the number varies from 104 to 107 cells per gram of soil. We then designed an instrument for detection of biomolecular fluorescence, and considered also fluorescence from polycyclic aromatic hydrocarbons and minerals on the Martian surface. The majority of the instrument is designed from Mars surface operation flight qualified components, drastically reducing development costs. The basic design adapts the ChemCam instrument package on-board Mars Science Laboratory rover Curiosity to detect organics via fluorescence. By placing frequency multipliers in front of the 1064 nm laser, wavelengths suitable for fluorescence excitation (266 nm, 355 nm, and 532 nm) will be achieved. The emission system is modified by the addition of band pass filters in front of the existing spectrometers to block out the excitation energy. Biomolecules and polycyclic aromatic hydrocarbons are highly fluorescent at wavelengths in the ultra violet (266 nm, 355 nm), but not as much in the visible 532 nm range. Preliminary results show minerals discovered, such as perchlorate, fluoresce highest when excited by 355 nm. Overall, we conclude the fluorescent instrument described is suitable to detect soil microbes, organics, biomolecules, and some minerals via fluorescence, offering a high scientific return for minimal cost with non-contact applications in extreme environments on Earth and on future missions to Mars.

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44

Archer, Paul Douglas. "The Martian Near Surface Environment: Analysis of Antarctic Soils and Laboratory Experiments on Putative Martian Organics." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195892.

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Understanding the physical properties as well as the potential for organic material in the Martian near-surface environment can give us a glimpse into the history of the site with regards to water, soil formation processes, as well as the conditions necessary for life. This work is done to support the interpretation of data from the Phoenix Mars Lander as well as other past and future landed missions. The Antarctic Dry Valleys are a hyper-arid cold polar desert that is the most Mars-like place on Earth. Soils from two different soil and climate regimes are analyzed to determine their physical properties such as mineralogy, particle size, shape, color, and specific surface area. These data are used to describe the sample locations in Antarctica and infer properties of Martian soils by comparison to Antarctic sites. I find that the particle size distribution can be used to determine the water history of the site and that the behavior of soluble species in the soil can also be used to trace the movement of water through the soil and could be instructive in understanding how soil organic material is processed by the environment. Continuing with the theme of soil organic matter, we revisit the Viking conclusions with regards to organics on Mars and look at the Phoenix data on the same subject. First, we assume that Mars receives organic material from meteoritic infall. These organics will be processed by chemical oxidants as well as UV light down to 200 nm. Chemical oxidation is predicted to produce molecules such as mellitic acid, which could preserve up to 10% of the original organic mass. Using mellitic acid and other similar organic molecules, we irradiate these molecules with Mars-like ultraviolet light, analyzing the gases that come off as irradiation takes place. We find that organic molecules can survive Mars-like UV conditions as layers of UV-resistant organics build up, shielding the remaining organic material. Additionally, the gas products of irradiation depend on the composition of the original organic molecule, implying that even irradiated molecules will carry some information about the composition of the original molecule. Finally, we take this irradiated organic/soil stimulant mixture and analyze it via pyrolysis, similar to the Viking GC/MS and TEGA instruments that are the only instruments operated on Mars capable of detecting organics. We find that the pyrolysis of mellitic acid (and other similar) molecules primarily produces inorganic fragments but that the reduced carbon fragments released depend on the composition of the original organic. However, the introduction of perchlorate, discovered on Mars by the Phoenix Lander, complicates the issue by creating the conditions for molecular oxidation. The high-oxygen content and high pyrolysis temperatures lead to organic combustion during thermal analysis, meaning that, regardless of the initial composition, most soil organics will be oxidized to CO₂ during the detection process. By assuming that organic material was oxidized to CO₂ in the Phoenix and Viking samples. We show that this assumption gives organic concentrations consistent with meteoritic accumulation rates. This finding reopens the possibility for organic molecules in the near-surface environment at the Viking and Phoenix landing sites.

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45

Tawfik, Rahmy. "A Novel Approach to the Discovery of Natural Products From Actinobacteria." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6766.

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Actinobacteria, primarily the genus Streptomyces, have led to the development of a number of antibiotics, which result from their secondary metabolites or modified derivatives. Secondary metabolite production can result from competition with neighboring microbes in an effort to disrupt growth, aiding in the competition for vital nutrients in impoverished conditions. Such secondary metabolites have the potential to affect a plethora of cellular functions in target cells, including, cell wall development, protein synthesis, protein function and fatty acid synthesis/metabolism. Due to the pandemic spread of antibiotic resistant bacteria, it is imperative to continue the search for new therapeutic agents targeting these deadly organisms. As such, our group explored soil and marine samples from Tampa Bay’s surrounding farmlands and waterways for secondary metabolite producing microbes using culture methods specific to Actinobacteria. Through these efforts we isolated over 750 bacterial species, of which almost half are confirmed Actinobacteria. In an attempt to derive new and novel chemistry from these organisms, we used our novel collection, and developed techniques for epigenetic modification to un-silence dormant and cryptic metabolic pathways. Our work reveals that a number of these Actinobacteria produce secondary metabolites that are effective against the ESKAPE pathogens, some at very low concentrations. Although the bioactivity from secondary metabolites is a well-known source for antibiotic drug discovery, our epigenetic methods suggest a potential to isolate previously overlooked compounds that have a very real possibility for use as antibacterial therapeutics.

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46

Karunatillake, Suniti, James J. Wray, Olivier Gasnault, Scott M. McLennan, Rogers A. Deanne, Steven W. Squyres, William V. Boynton, J. R. Skok, Nicole E. Button, and Lujendra Ojha. "The association of hydrogen with sulfur on Mars across latitudes, longitudes, and compositional extremes." AMER GEOPHYSICAL UNION, 2016. http://hdl.handle.net/10150/621428.

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Midlatitudinal hydrated sulfates on Mars may influence brine pH, atmospheric humidity, and collectively water activity. These factors affect the habitability of the planetary subsurface and the preservation of relict biomolecules. Regolith at grain sizes smaller than gravel, constituting the bulk of the Martian subsurface at regional scales, may be a primary repository of chemical alteration, mechanical alteration, and biosignatures. The Mars Odyssey Gamma Ray Spectrometer with hundreds of kilometers of lateral resolution and compositional sensitivity to decimeter depth provides unique insight into this component of the regolith, which we call soil. Advancing the globally compelling association between H2O and S established by our previous work, we characterize latitudinal variations in the association between H and S, as well as in the hydration state of soil. Represented by H2O:S molar ratios, the hydration state of candidate sulfates increases with latitude in the northern hemisphere. In contrast, hydration states generally decrease with latitude in the south. Furthermore, we observe that H2O concentration may affect the degree of sulfate hydration more than S concentration. Limited H2O availability in soil-atmosphere exchange and in subsurface recharge could explain such control exerted by H2O on salt hydration. Differences in soil thickness, ground ice table depths, atmospheric circulation, and insolation may contribute to hemispheric differences in the progression of hydration with latitude. Our observations support chemical association of H2O with S in the southern hemisphere as suggested by Karunatillake et al. (2014), including the possibility of Fe sulfates as a key mineral group.

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47

Moro, Valério. "Manejo de alturas da pastagem de aveia preta mais azevém e uso de suplementação para cabras pré e pós parto." Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/275.

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O experimento foi conduzido na área experimental do IAPAR (Instituto Agronômico do Paraná) em Pato Branco - PR, de abril a outubro de 2009 para avaliar duas alturas da pastagem (12 e 21 cm) associadas ou não com suplementação energética (0,0 e 1,5% PV), em esquema fatorial 2x2, em blocos casualizados com três repetições. Os animais foram 36 cabras boer (55 kg de peso inicial) no estágio fisiológico de pré e pós parto, em pastagem de aveia (Avena strigosa Schreb) mais azevém (Lolium multiflorum Lam). A pastagem foi manejada sob lotação contínua e taxa de lotação variável para manter as alturas pretendidas para cada intensidade de pastejo. Foi avaliado o comportamento dos nutrientes no solo e de alguns atributos químicos em três profundidades amostradas (0-5, 5-10, 10-20 cm). Atributos químicos como pH-CaCl2, saturação de alumínio, soma de bases e saturação de bases, bem como alguns macro e micronutrientes, como potássio, magnésio, fósforo, ferro, manganês, cobre e zinco tiveram efeito apenas da profundidade amostrada. Conclui-se que manejando a pastagem a 12 cm com uso de suplementação, evita-se o aumento de teores de alumínio trocável em profundidade, assim como, aumentou os teores de Ca, o que minimiza problemas de degradação química do solo nas áreas de pastejo. A taxa média de acúmulo da forragem foi de 60 kg MS.ha־¹.dia־¹ e a produção total obtida em 180 dias foi 10.283 kg MS.ha־¹. A oferta de forragem foi influenciada pelas interações entre período e altura da pastagem, período e suplemento, assim como suplemento e altura da pastagem. A oferta média de forragem foi 8,32 e 4,30 kg MS.100-1 kg de PV na altura de 21 e 12 cm da pastagem, respectivamente. A carga animal total teve efeito da suplementação, sendo obtido 3.433 e 1.789 kg PVha-1dia-1 com e sem suplementação, respectivamente. Tanto o ganho médio diário como ganho por área foram negativos. O escore de condição corporal das cabras foi influenciado pelos tratamentos, com menores perdas na pastagem conduzida a 21 cm e com suplementação. O peso ao nascer dos cabritos não teve influencia dos tratamentos, nem do sexo. Cabritos acompanhados de suas mães na ausência de suplemento pastejaram 57,76% do tempo das mães, e com isso obtiveram melhor desempenho a partir de 25 dias de idade. O tempo de pastejo das cabras foi maior na ausência de suplementação, enquanto, o tempo de ócio foi maior nas cabras suplementadas.
The trial was carried out at IAPAR (Instituto Agronômico do Paraná) in Pato Branco - PR, from April to October 2009 to evaluate two canopy height (12 and 21 cm) either associated or not with energetic supplementation. It was compared two grazing intensities associated or not with energetic supplementation (0.0 e 1.5% of body weight - BW) in 2x2 split-plot design in Completely randomized blocks and three replicates. There were evaluated 36 boer breed goats (55 kg of initial weight) during either pre and pos lambing on black oat (Avena strigosa Schreb) plus annual ryegrass (Lolium multiflorum Lam) pasture. The pastures were continuously stocked using the put and take technique to maintain the height target to each grazing intensity. It was evaluated nutrients and chemical compound dynamic into three depths soil (0-5, 5-10, 10-20 cm). pH-CaCl2, Al saturation, sum of cation, cation saturation, likewise some macro and micronutrients (K, Mg, P, Fe, Mn, Cu, and Zn) were influenced just by sample depth. It can be concluded that 12 cm canopy height plus supplementation, the increase of exchangeable Al can be avoided at deep. As well as, Ca concentration in the soil was increased, which minimize chemical degradation of the soil in grazing lands. Forage accumulation rate was 60 kg DM.ha־¹.day־¹ and 10,283 kg DM.ha־¹ of total forage production was obtained whithin 180 days. Herbage allowance was influenced by period * height, period * supplementation, and supplementation * height interactions. Average herbage allowance was 8.32 and 4.30 kg MS.100-1 kg of BW for 21 and 12 cm of canopy height, respectively. Supplementation affected stocking rate which values were 3,433 and 1,789 kg BW.ha-1day-1 in presence and absence of supplementation, respectively. Average daily weight gain and gain per area were negative. Goat body condition score was affected by treatments, lesser body weight loss was verified in the 21 cm canopy height plus supplementation. Birth weight of kids had no effect neither treatments nor sex. Kids accompanied for their mothers without supplementation grazed 57.76% of grazing time of the goats, and performed better since 25 days old. Goat grazing time was higher in no supplementation treatments, whereas idling time was higher for goats supplemented.

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48

South, Patrick. "Discovery of a Novel Inhibitory Compound Produced by the Soil Bacterium Rhodococcus sp. MTM3W5.2." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/honors/458.

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Due to increases in antibiotic resistance stemming from the overuse of commercial antibiotics, the need to discover novel antibacterial compounds is becoming more urgent. A species of Rhodococcus, MTM3W5.2, has been discovered and was found to produce a metabolite with inhibitory activity against closely related species. The aim of this study is to elucidate the structure of the inhibitory metabolite by isolating and purifying it; then characterizing it using spectroscopic techniques. The compound was isolated from MTM3W5.2 RM broth cultures using n-butanol extraction, which yielded an active crude extract. The crude extract was then subjected to fractionation using a Sephedex LH-20 column with a 100% methanol solvent. The inhibitory activity of the fractions was tested through disk diffusion assay using Rhodococcus erythropolis as an indicator. Further preparation was completed using preparative reverse-phase high-performance liquid chromatography. Advanced purification was conducted by multiple rounds of analytical reverse-phase HPLC. Throughout the study the HPLC fractions were characterized and stability was monitored using UV-Visible spectroscopy. Two pure samples at 58.xx and 72.xx minutes from HPLC collections were selected for further structural identification and are currently being studied using spectroscopic techniques, most notably 2D NMR

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49

Lewis, Matthew A. "Soil-Specific, Late-Season Nitrogen and Potassium Applications to Increase Corn Yields in the Mid-Atlantic Coastal Plain." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/31860.

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Corn grain yields can be limited by nitrogen (N) and potassium (K) availability on sandy coastal plain soils when soil moisture is adequate for high yields. This study evaluated irrigated corn grain yield response to late-season (just prior to tassel) N and K fertilizer applications, and enabled the proposal of a method to predict potential for corn to utilize late-season N applications based on soil moisture. In an experiment to evaluate late-season fertilizer application rates, N and K were applied in a complete factorial of five N and K rates ranging from 0 to 112 kg ha-1. Additionally, water use of high yielding corn was measured, and historical weather patterns evaluated in an effort to predict the need for late-season fertilizer applications based on soil moisture. Grain yield was increased significantly by late-season N applications in three of four experiments. Potassium applications did not affect yield, and there were no interactions between N and K. Significant drainage due to high rainfall levels in 2000 prohibited further refinement of corn water use data for Virginia climatic conditions. Historical weather patterns, potential evapotranspiration of corn, and soil water holding properties were evaluated. In order to provide corn with adequate moisture during a two-week moisture-sensitive critical period beginning at tassel, soils must be near field capacity at the start of the period and receive above-average (75th percentile) rainfall during the period.
Master of Science

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50

Acosta, Juan José Bonnin 1970. "Índice de cone, capacidade de suporte de carga e teor de água de quatro solos da Fazenda Lageado, Botucatu/SP : correlações r mapas de isocompactação /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/101696.

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Resumo: O presente trabalho objetivou avaliar a ocorrência e distribuição da compactação, bem como a influência temporal do teor de água do solo na sua resistência à penetração medida através do índice de cone (IC), correlacionando-a com o modelo de capacidade de suporte de carga do solo, visando estabelecer um procedimento que permita localizar e visualizar pontos ou zonas compactadas. Os experimentos foram realizado na Fazenda Lageado da UNESP/FCA, Botucatu/SP., sendo selecionados quatro diferentes tipos de solos, sendo: solo 1: LATOSSOLO VERMELHO (LV), textura média, teores de argila entre 15 a 34 %, e elavdo grau de intemperização; solo 2: NEOSSOLO FLÚVICO (RU), oriundo de materiais não consolidados, de deposição recente, desenvolvidos sob releve plano, revelando camadas nitidamente estratificadas, ou seja, extratos granulometricamente muito distintos, podendo aparecer camadas argilosas sobrepostas a camadas arenosas ou vice-versa; solo 3: NITOSSOLO VERMELHO distroférrico, de textura argilosa, com teores de argila superiores a 50 %, manejada em sistema de plantio direto e solo 4: NITOSSOLO VERMELHO distroférrico, de textura argilosa, com teores de argila superiores a 50 %, preservada em pousio por vários anos. Utilizou-se um penetrômetro hidráulico-eletrônico para a amostragem da resistência mecânica do solo à penetração, em 5 épocas diferentes, nas profundidades de 0 a 0,10; 0,10 a 0,20; 0,20 a 0,30; 0,30 a 0,40 m. O teor de água do solo foi monitorado durante a avaliação do IC, nas profundidades de 0 a 0,20 e de 0,20 a 0,40 m. A análise espacial foi realizada através da geoestatística, para a construção do semivariograma e através da técnica de interpolação, construíram-se os mapas de isocompactação do solo. A evidência da relação entre o teor de água do solo e o IC de mapas interpolados nem sempre foi possível...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this work was to evaluated the soil compaction and its distributions, soil water content influence on the soil resistance measured by the soil cone index (CI), correlating the soil load capacity model in order to establish a procedure able to locate points or zones with soil compaction. The experimental area was at Lageado Experimental Farm, UNESP/FCA, Botucatu/Sao Paulo. Different soil type was used and a hydraulic-electronic penetrometer was used to measure the soil resistance at 0-0.10; 0.10-0.20; 0.20-0.30 and 0.30-0.40 m. During the soil cone index sampling, soil core samples were taken at 0-0.20m and 0.20-0.40m depths in 5 different dates. Geostatistic was used to analyze the spatial variability and semivariograms were done. Using interpolation techniques isocompaction maps were made. The relation between soil water content and soil cone index sometimes was not possible, mainly in place where the soil was extremely wet or extremely dry. Mean soil cone index values and water content value for area 1 were between 1.42 to 8.99 MPa and 9.59 to 17.63%, respectively. On the area 2 the soil cone index was between 0.3 to 5.65 MPa and water content value was between 13.64% to 27.92%. On the area 3 the CI was between 1.58 to 8.17 MPa and water content value was between 17.46% to 31%, and for the area 4 the IC and water content value was 1.16 to 6.24 MPa and 16.76 to 23.49%, respectively. Those results showed a spatial heterogeneity for those parameters. Models of soil load capacity esteem quite well the preconsolidation pressure ( p) in function of soil water content, allowing identifying, in each area, the layer with higher mechanical resistance probably more affected by the traffic and soil tillage. The p could be determined in function of CI and reviewed to be an excellent tool to identify point or zone with soil compaction or with higher mechanical resistance...(Complete abstract, click electronic access below)
Orientador: Kléber Pereira Lanças
Coorientador: José Manuel Miras Avalos
Banca: Saulo Philipe Sebastião Guerra
Banca: Silvio José Bicudo
Banca: Antonio Gabriel Filho
Banca: Antonio José da Silva Maciel
Doutor

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