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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Riktvärden för förorenad mark : En undersökning av hur riktvärden för förorenad mark har förändrats gentemot tidigare riktvärden samt hur de påverkas av variationer i geologiska och hydrogeologiska parametrar

Levin, Sara January 2009 (has links)
Risk assessment is made to determine risks with contaminated areas and to determine which treatment the area requires. In Sweden, risk assessment is divided into three levels: risk analysis, facilitated risk assessment and detailed risk assessment. In detailed risk assessment site-specific guideline values are developed to compare with values of contaminants that are measured in the area. Site-specific guideline values vary with geological and hydrogeological parameters. The purpose of this report is to examine which of these parameters that affect the guideline values. The examination was done using a calculating program for consideration from the Swedish Environmental Protection Agency from the year of 1997. The study shows that some of the geological and hydrogeological parameters affect the site-specific guideline values for metals in different ways and others do not.   Using the program from the Swedish Environmental Protection Agency is a simple way to calculate site-specific guideline values. It’s important to make sure that relevant values are chosen to get correct results. The calculating program is still not definitive so it’s important to be careful when using it. Another purpose of the report is to compare how guideline values have developed from the Swedish Environmental Protection Agency’s model for calculating guideline values from the year of 1997 with their new report whit the same purpose from the year of 2007. Guideline values for all metals that have been considered are lower in the new model from the year of 2007 compared to the model from the year of 1997.
202

The role of Caulobacter crescentus XerC and XerD recombinases in site-specific recombination

Liu, Hua 12 1900 (has links)
XerC et XerD, deux recombinases impliquées dans la recombinaison site spécifique, résolvent les multimères d’ADN en monomères. Cette réaction se produit au niveau du site dif du chromosome, et nécessite le domaine C-terminale de la protéine de division cellulaire FtsK. Caulobacter crescentus est une bactérie aquatique de type Gram-négative qui se retrouve dans plusieurs environnements. Elle présente un cycle cellulaire asymétrique avec deux types de cellules distinctes. Cette propriété peut être utilisée pour synchroniser la croissance d’une population bactérienne pour permettre l’étude de l’expression de gènes à travers le temps et les liens entre le cycle cellulaire et le développement de la bactérie. La liaison à l’ADN et la capacité de former des complexes covalents (phosphotyrosyl) avec le site dif de C. crescentus (ccdif) ont été testé pour les recombinases de C. crescentus (ccXerC et ccXerD). Les deux recombinases ont eu une meilleure liaison au demi-site gauche de ccdif et sont incapable d’effectuer une liaison coopérative, contrairement à ce qui se produit au niveau du site dif de E. coli. La formation de complexes covalents a été testé en utilisant des «substrats suicides avec bris» marqués à la fluorescence ainsi que des protéines de fusion (marquées ou non à la fluorescence). Des complexes ADN-protéines résistants à la chaleur et au SDS ont été observé lors de la réaction de ccXerC et ccXerD de type sauvage avec ccdif, mais pas lors de la réaction de mutants avec le même ADN. Des complexes covalents phosphotyrosine sont formés de façon plus efficace sur les substrats suicides avec un bris au niveau du brin supérieur que ceux ayant un bris au niveau du brin inférieur. Dans les deux cas, c’est ccXerC qui est resté lié de façon covalente à l’ADN de ccdif. / In most bacteria, the chromosomal dimer resolution process is mediated by two tyrosine recombinases, XerC and XerD, which bind cooperatively and perform the recombination reaction at the dif site near the terminus of replication. This reaction also requires the C-terminal domain of the cell division protein FtsK. Caulobacter crescentus is an aquatic Gram-negative bacterium found in various environments. This bacterium has an asymmetric cell cycle which can be used to synchronize cell growth in order to study the temporal expression of a gene and the interconnection between the cell cycle and development. The binding activity and the formation of phosphotyrosyl complex of the C. crescentus recombinases, ccXerC and ccXerD, were tested on the C. crescentus dif (ccdif) site. Both ccXerC and ccXerD bound preferentially to the left half-site of ccdif and showed reduced cooperative binding, unlike what was found with the E. coli dif site. Covalent complex formation activity was tested by using fluorescently labelled linear “nicked suicide substrates” and labelled proteins. Heat and SDS-resistant protein-DNA complexes were formed when both wild-type ccXerC and ccXerD reacted with ccdif but not in the presence of active-site tyrosine mutant proteins. Phosphotyrosine complexes formed on the top-nicked suicide substrate were found to be more efficient than on the bottom-nicked suicide substrates and surprisingly ccXerC remained bound to both top and bottom-nicked ccdif suicide substrates.
203

Intracellular systems for characterization and engineering of proteases and their substrates

Kostallas, George January 2011 (has links)
Over the years, the view on proteases as relatively non-specific protein degradation enzymes, mainly involved in food digestion and intracellular protein turnover, has shifted and they are now recognized as key regulators of many biological processes that determine the fate of a cell. Besides their biological role, proteases have emerged as important tools in various biotechnical, industrial and medical applications. At present, there are worldwide efforts made that aim at deciphering the biological role of proteases and understanding their mechanism of action in greater detail. In addition, with the growing demand of novel protease variants adapted to specific applications, protease engineering is attracting a lot of attention. With the vision of contributing to the field of protein science, we have developed a platform for the identification of site-specific proteolysis, consisting of two intracellular genetic assays; one fluorescence-based (Paper I) and one antibiotic resistance-based (Paper IV). More specifically, the assays take advantage of genetically encoded short-lived reporter substrates that upon cleavage by a coexpressed protease confer either increased whole-cell fluorescence or antibiotic resistance to the cells in proportion to the efficiency with which the substrates are processed. Thus, the fluorescence-based assay is highly suitable for high-throughput analysis of substrate processing efficiency by flow cytometry analysis and cell sorting, while the antibiotic resistance assay can be used to monitor and identify proteolysis through (competitive) growth in selective media. By using the highly sequence specific tobacco etch virus protease (TEVp) as a model in our systems, we could show that both allowed for (i) discrimination among closely related substrate peptides (Paper I & IV) and (ii) enrichment and identification of the best performing substrate-protease combination from a background of suboptimal variants (Paper I & IV). In addition, the fluorescence-based assay was used successfully to determine the substrate specificity of TEVp by flow cytometric screening of large combinatorial substrate libraries (Paper II), and in a separate study also used as one of several methods for the characterization of different TEVp mutants engineered for improved solubility (Paper III). We believe that our assays present a new and promising path forward for high-throughput substrate profiling of proteases, directed evolution of proteases and identification of protease inhibitors, which all are areas of great biological, biotechnical and medical interest. / QC 20110516
204

Functional domains of P450 1A1 and 1A2 molecular modeling-guided structure-function study /

Tu, Youbin. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains vii, 143 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
205

Analyzing the interconnectedness between space, place, and human interaction with the natural environment: "Ecological reawakening: Organic DNA and evolution"

Moos, Sarah 24 April 2009 (has links)
I have organized this paper into four chapters: "The Environmental Situation," "Space and Place," "Art and the Natural Environment," and "Creating Work of My Own." Chapter 1 explains human beings' intrinsic interconnection to the natural environment, outlining why humans should be concerned about the current degraded state of the natural world. Chapter 2 discusses the concepts of space and place. It analyzes how human beings interact with and experience spaces, developing their sense of place - within physical, theoretical, and spiritual realms. It finally illustrates the importance that spaces and places have in humans' lives. Chapter 3 describes the Land Art phenomenon: its development, the different forms within it, and artists producing Land Artworks. The forms and artists included are those that have been inspirational for the development of my own work. It also emphasizes Land Art as a fundamental form for improving humans' relationship with the natural environment and the new realm of eco-feminism that resonates with Land Art ideals. Chapter 4 recounts the development of my art throughout my college career. It describes my work as site-specific, sculptural installations that use natural materials. It also states why this format is the most effective for my senior art thesis project. Focusing mainly on "Ecological Reawakening: organic DNA," it explains the mentality in designing, creating, installing, and completing the work. Overall, Chapter 4 emphasizes the work's two main goals: to demonstrate a new avenue for comprehending humankind's place within earth's environmental spaces, and to advocate for an environmental paradigm shift during the twenty-first century. Finally, Chapter 5 describes the transformation of "Ecological Reawakening: organic DNA" as it developed over time during the spring honors senior thesis course. It details my mentalities in adding living plant matter to the structure, incorporating a stool into the piece, and creating "Evolution," the digital photography composition that documents "Ecological Reawakening" and was included in the Scripps Senior Art Exhibition in the Ruth Chandler Williamson Gallery from May 1 – May 17, 2009.
206

MANEJO DE LAGARTAS E PERCEVEJOS DA SOJA COM CONTROLE LOCALIZADO / SITE-SPECIFIC MANAGEMENT OF CATERPILLARS AND STINK BUGS IN SOYBEAN CROP

Aita, Valmir 18 February 2013 (has links)
Soybean [Glycine max (L.) Merrill] is the most important crop grown in Brazil and worldwide. Nevertheless, the yield is still limited by several issues in which the damages by caterpillars and stink bugs are main ones if not controlled efficiently. The pest control is usually achieved by insecticide application, which results in an increased production cost, disturb biological control, and causes contamination in harvest and environment, so it is necessary to develop news techniques aiming to reduce the amount of sprayed insecticides. The preset study was carried out in five soybean grown areas during 2010/11 and 2011/12. This experiment aimed to analyze the spatial and temporal distribution in order to perform site-specific control of caterpillars and stink bugs by using agriculture-precision tools for mapping and control of insects. In addition, the technical and economic effects of this approach were surveyed. The first chapter shows the site-specific control for caterpillars while the chapter two for stink bugs. The population of soybean caterpillars can be suppressed by site-specific approach where the population exceeds the economic threshold and therefore saving insecticide. The site-specific control for stink bugs in soybean allows save insecticide and decreases the bugs population, but causes outbreaks far beyond the economic threshold. Economically speaking, the site-specific control of caterpillars and stink bugs is possible, but requires further studies to optimize the sampling procedure. / A soja [Glycine max (L.) Merrill] é uma cultura de grande expressão no Brasil e no mundo, no entanto a sua produtividade ainda é limitada por diversos fatores, onde destacam-se os danos significativos causados pelas lagartas e percevejos quando não manejadas eficientemente. O controle destes insetos é geralmente feito com aplicações de inseticidas, o que ocasiona o aumento dos custos da lavoura, prejudica o controle biológico pela morte de inimigos naturais, e deixa resíduos tóxicos no produto colhido e no ambiente, por isso, se faz necessário desenvolver técnicas visando a sua utilização mais eficiente, que resulte em menores quantidades aplicadas. Este estudo foi realizado em cinco áreas de cultivo com soja nas safras 2010/11 e 2011/12 objetivando analisar a distribuição espacial e temporal e realizar o controle localizado de lagartas e percevejos em soja, utilizando técnicas de agricultura de precisão para o mapeamento e controle dos insetos. Também foi realizada a análise técnica e econômica deste sistema de manejo. O primeiro capítulo apresenta o estudo do controle localizado de lagartas e o segundo capítulo o estudo do controle localizado de percevejos em soja. A população de lagartas da soja pode ser controlada de forma localizada nos pontos onde a população ultrapassa o nível de controle, proporcionando economia de inseticida. O controle localizado de percevejos em soja permite economia de inseticida e reduz a população, mas não impede a reinfestação da área acima do nível de controle. Em termos econômicos, o controle localizado de lagartas e percevejos é viável, porém são necessários estudos para aperfeiçoar o sistema de amostragem.
207

The states and status of clay : material, metamorphic and metaphorical values

Buzz, Lu La January 2018 (has links)
This doctoral project combines a performance-led practice with contextual research in order to demonstrate how arts practice can challenge historical perceptions of clay and enhance its material status. The core knowledge deduced from this research is that embodied performance transforms connectivity between artist and clay and produces a unified incarnation of both elements. Through the use of immersive research methods I gained insights which could not have been predicted - particularly that my experiential performances were a process of ‘clay becoming’ in which I ultimately became the clay. In terms of locality, the practice, comprising eight performance-led works and related documentation, focuses on the China Clay and Ball Clay of South West England. Traditionally in the arts, these materials are associated with ceramics, where through heating, clay becomes rigid and fixed. In contrast, my research investigates the textural fluidity and metamorphic potential of these clays in their raw state. The practice encompasses two interrelated groups of work; the In-breath and Out-breath. These terms are significant in three respects. Firstly they define two different modes and moments of practice. Secondly they refer to myself as a living component of these practices. Thirdly they reflect the cultural associations of clay as a metaphor for life. During the initial exploratory ‘In-breath’ phase of my practice, comprising four site-specific pieces, I engaged with clay at sites of historical relevance, building an expansive knowledge of my material. During the later ‘Out-breath’ phase, identification with site was relinquished. These works took place within neutral spaces, allowing the clay to be explored in relation to my body. The introduction of layering, where photographic elements of private clay rituals were situated within the context of a live performance, allowed a texturally dynamic and immersive experience to be created for both artist and viewer. By collecting and preserving clay traces from these live performances (e.g. foot and body prints) additional value was given to the embedded significance of the clay.
208

Variabilidade espacial de atributos do solo que influenciam a produção de arroz vermelho no Vale do Apodi - RN / Spatial variability of soil attributes influencing red rice production in Apodi Valley, RN, Brazil

Barreto, Herlon Bruno Ferreira 29 June 2012 (has links)
Made available in DSpace on 2016-08-31T13:24:16Z (GMT). No. of bitstreams: 1 HerlonBFB_DISSERT.pdf: 1494254 bytes, checksum: bd30d753b8f120d23416ecf468c1672c (MD5) Previous issue date: 2012-06-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Irrigated red rice has been cultivated for decades in Apodi Valley, Brazil, where it is a cash crop and main economic resource for many small farm families. However, in other regions of Brazil red rice is little known and little cultivated. This study had as objective to assess spatial variability of soil attributes that influence irrigated red rice production in Apodi Valley, and characterize spatial dependence of those attributes and also of rice yield. The work was carried out in two farms of the county of Apodi, RN, Brazil, in a lowland region where is established the Apodi Valley Association of Red Rice Growers. Each farm had a production area divided in fifteen subareas, from which were determined soil chemical and physical-hydric characteristics. Samples were taken at 0 - 15 and 15 30 cm depths, according to a grid with regular spacing of 20 x 20 m in Area 1 and 10 x 10 m in Area 2. Sampling spots were georeferenced according to Cartesian coordinates that allowed the use of geostatistics in the study of spatial variability. Physical-hydric determinations included soil texture, permanent wilting point, field capacity, soil density, particle density and available water content. Soil chemical determinations included organic matter content and contents of Ca2+, Mg2+, K+, Na+, P, Cu2+, Mn2+, Fe2+ and Zn2+. Rice yield components determined were panicle number per area, mass of hundred grains and yield. Descriptive statistics was used for analyzing data general behavior and to identify outliers. Spearman correlation and multiple linear regression analysis were used for identifying probable causes of variability. Mean yields obtained were 7527 kg ha-1 and 3832 kg ha-1, in areas 1 e 2, respectively. Soil physical-hydric variables correlated to production components were: available water content, permanent wilting point, soil density and contents of clay and silt. Soil chemical variables correlated to rice yield components were: calcium, magnesium, phosphorus, sodium, potassium, zinc, copper, manganese, iron and organic matter / O arroz vermelho vem sendo cultivado há dezenas de anos no Vale do Apodi, onde gera renda e é o principal sustentáculo econômico para muitas famílias de pequenos agricultores. Entretanto, o arroz vermelho, é pouco conhecido e, portanto, pouco cultivado em outras regiões. O objetivo do presente trabalho foi o de determinar a variabilidade espacial de atributos físico-hídricos e químicos do solo que influenciam a produção do arroz vermelho irrigado na região do Vale do Apodi, e caracterizar a dependência espacial dos atributos do solo e da produção visando fornecer subsídios para um posterior planejamento da produção. O trabalho foi realizado no município de Apodi, RN, na região conhecida como várzea do rio Apodi, compreendendo a área de abrangência da Associação dos Produtores de Arroz do Vale do Apodi. O trabalho foi realizado em duas propriedades, nas quais foi delimitada uma área, subdividida em quinze subáreas, sendo cada caracterizada em suas características químicas e físico-hídricas do solo. As amostragens e coletas foram realizadas nas profundidades de 0-15 e 15-30 cm, segundo malhas de amostragem com espaçamento regular, o qual foi de 20x20 m na Área 1, na comunidade Santa Rosa, e 10x10 m na Área 2, na comunidade Reforma. Os pontos de amostragem foram referenciados segundo coordenadas cartesianas (x,y), permitindo assim o uso da geoestatística para estudar a variabilidade espacial das características. A determinação das características físico-hídricas do solo foi realizada a partir de amostras deformadas e indeformadas, as quais foram obtidas em anéis volumétricos de aço. As determinações físico-hídricas do solo foram análise textural, ponto de murcha permanente, capacidade de campo, densidade aparente, densidade de partículas e água disponível. As determinações químicas do solo foram os teores de matéria orgânica, Ca2+, Mg2+, K+, Na+,P, Cu2+, Mn2+, Fe2+ e Zn2+. Os componentes de produção determinados foram número de panículas por área, massa de 100 grãos e produtividade. A estatística descritiva foi empregada para analisar o comportamento geral dos dados e identificar possíveis valores discrepantes. O coeficiente de correlação de Spearman e a análise de regressão linear múltipla foram utilizados para identificar causas prováveis de variabilidade. As produtividades médias foram de 7.527 kg ha-1 e 3.832 kg ha-1, para área 1 e 2, respectivamente. As variáveis físico-hídricas do solo que se correlacionaram com os componentes de produção foram: água disponível, ponto de murcha, densidade aparente, argila e silte. As variáveis químicas do solo que se correlacionaram com os componentes de produção foram: cálcio, magnésio, fósforo, sódio, potássio, zinco, cobre, manganês, ferro e matéria orgânica
209

Qualidade física de um latossolo sob plantio direto submetido à escarificação de sítio específico e o rendimento da soja / Oxisol s physic quality afyer site specific chisel tillage and soybean yield under no-till

Girardello, Vitor Cauduro 26 February 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The soil compaction has been noted under no-till especially in clay soil texture. One important characteristic of soil compaction in cropland is non-uniform occurrence. With precision farming (PF) is possible determine spatially the soil compaction allowing the site specific management defined as site specific chisel (SSC). This work was carried out in a cropland managed with PF in Victor Graeff, RS. The soil is Red Latossol with Cfa climate following Koppen classification. The treatments were: a) conventional chisel tillage (CCT); b) site specific chisel with uniform depth (SSCU); c) site specific chisel with variable depth (SSCV) and d) check plot - non disturbed soil (NC). The main evaluations were: water infiltration and other soil physic characteristics: macroporosity, microporosity, total porosity, relative density and aggregate stability soil layers: 00-0.05, 0.05 0.1, 0,1 0.15 e 0.15 -0.20 m , yield map, soil cover, soil resistance assessed by penetrometer, fuel consumption. The soil resistance indicated the soil compaction occurrence in zones of the cropland. The chisel tillage improved the soil physic characteristics, but it didn t improve the soybean yield. Besides that, the infiltration rate was increased five times, but after seven months the infiltration rate decreased 70%. The site specific chisel maintains 70% of soil cover, while conventional chisel only 25%. It was found high relationship between soil resistance and soybean yield (r2=0.87) and soil resistance and temporal yield variability (r2=0.97). / A compactação tem sido observada no sistema de plantio direto (SPD), principalmente em solos com textura argilosa. Uma característica importante da compactação é que a sua ocorrência é desuniforme dentro da área. Com técnicas de agricultura de precisão (AP) é possível identificar os locais onde ela ocorre, possibilitando a intervenção localizada, chamada de escarificação de sitio especifico (ESE). Este trabalho foi conduzido em uma área comercial, manejada sob o SPD utilizando técnicas de AP no município de Victor Graeff, RS. O solo do local é um Latossolo Vermelho com clima subtropical do tipo Cfa úmido segundo a classificação de Koppen. Os tratamentos foram: a) Escarificador Convencional (EC); b) escarificador de atuação sítio específico com profundidade Fixa (ESE-Prof. Fixa); c) escarificador sítio específico com variação de profundidade (ESE-Prof. Variada); e d) testemunha - Sem Escarificar (SE). As avaliações foram: infiltração de água, macroporosidade, microporosidade, porosidade total, densidade relativa do solo e agregação, avaliação de mapas de rendimento, determinação da cobertura vegetal, geração de mapas de resistência a penetração com penetrômetro (RP), consumo de combustível na operação de escarificação. O mapa de RP indicou a ocorrência da compactação de forma localizada na área. A escarificação apresentou melhoria nas propriedades físicas do solo, mas não incrementou o rendimento. Aumentou a taxa de infiltração de água no solo em cinco vezes em relação à testemunha, porém estes valores decresceram em até 70% após sete meses que ela foi realizada. O escarificador sítio específico manteve cerca de 70% de cobertura vegetal, enquanto o escarificador convencional 25%. Encontrou-se elevada correlação entre a RP (R2=0,87) e o rendimento e RP e variabilidade temporal do rendimento e (R2=0,97) respectivamente.
210

AGRICULTURA DE PRECISÃO: MANEJO DA FERTILIDADE COM APLICAÇÃO A TAXA VARIADA DE FERTILIZANTES E SUA RELAÇÃO COM A PRODUTIVIDADE DE CULTURAS / AGRICULTURE OF PRECISION: MANAGEMENT OF THE FERTILITY WITH APPLICATION OF THE VARIED RATE OF FERTILIZERS AND ITS RELATION WITH CROP YIELDS

Bellé, Gustavo Luiz 27 March 2009 (has links)
The agriculture of precision has been an important tool for the characterization of the spatial variability of soil attributes and crops. Thus, there is many options to elaborate thematic digital maps that can improve the soil and crop management. In this work, two croplands that has been managed with precision agriculture during several years were selected. One of them was called field Lagoa, it is a 132 ha, and the other, is field Schmidt, it is a 125 ha. In both croplands soil samples were collected with regular grid of 100 x 100 m. In the field Lagoa three soil sampled were done while in the field Schmidt two soil sampled were done along four years of evaluation. In order to investigate the crop yield variability, the yields data were collected with a combine MF34, equipped with yield sensor, GPS (Global Position System), board computer (Datavision). In the field Talhao, the yield maps were made to corn 2004/05, wheat 2005, soybean 2005/06, soybean 2006/07, corn 2007/08 and, in the field Schmidt, crop data were collected to soybean 2004/05, soybean 2005/06, soybean 2006/07 and corn 2007/08. The yield data and soil data were processed in the softwares SGIS® and Campeiro 6.0. The variable rate fertizer was done with equipment Hércules 10.000 equipped with disks system to immediate change the fertilizer rate . The evolution of soil fertility indicate that, in areas with high phosporus and potassium levels, the range of variation was maintained through the years, although, with a decrease in extreme values. The correlations of soil attributes with crop yield maps were higher in the field Schmidt mainly to CEC, Mg, organic matter, Ca, and, in the field Lagoa there was correlation, mainly, with organic matter. The match distribution and potassium the varied rate allowed that the nutrient supply was enlarged e/ou above below the export of the cultures, not interfering in the revenue. The crop yield map was an efficient tool to define yield zones driving the site specific management of fertilizers and soil management. / A agricultura de precisão tem se mostrado uma ferramenta importante, principalmente, para a caracterização da variabilidade espacial de atributos de solo e das culturas. Assim, há varias possibilidades de elaboração de mapas temáticos que poderão melhorar as intervenções de manejo no solo e ou na cultura. Neste trabalho foram avaliadas duas áreas que vem sendo manejadas com técnicas de AP ao longo dos anos, sendo uma delas, denominada talhão Lagoa, contendo 132 ha, e a outra, talhão Schmidt, contendo 125 ha. Em ambos os talhões foram coletadas amostras de solo com grade regular de 100 x 100 m, sendo que, no talhão lagoa foram três coletas de solo e no talhão Schmidt foram duas coletas de solo ao longo de quatro anos de avaliação. Para a caracterização da variabilidade das culturas, foi utilizada a coleta de dados através de uma colhedora MF34, equipada com sensor de rendimento, GPS (Sistema de Posicionamento Global), computador de bordo (Datavision). No talhão Lagoa, foram confeccionados mapas de colheita nas culturas de milho 2004/05, trigo 2005, soja 2005/06, soja 2006/07, milho 2007/08 e, no talhão Schmidt, foram coletados dados de colheita nas culturas de soja 2004/05, soja 2005/06, soja 2006/07 e milho 2007/08. Os resultados de colheita e solo foram processados nos softwares SGIS® e Campeiro 6.0. As aplicações a taxa variada foram realizadas com o equipamento Hércules 10.000 equipado com sistema de disco para distribuição a lanço dos fertilizantes com variação instantânea das doses. Os resultados de fertilidade indicaram que, em áreas com altos teores de fósforo e potássio, a amplitude de variação foi mantida ao longo dos anos, porém, com a diminuição de valores extremos. As correlações de atributos de solo com mapas de colheita foram maiores no talhão Schmidt para os atributos Schmidt para os atributos CTC, magnésio, matéria orgânica e cálcio e, no talhão Lagoa houve correlação positiva, principalmente, com matéria orgânica, ao longo das safras agrícolas. A distribuição de fósforo e potássio a taxa variada permitiu que fosse ampliado o fornecimento de nutriente acima e/ou abaixo da exportação das culturas, não interferindo no rendimento. Com isso, o mapeamento do rendimento da cultura foi uma ferramenta eficiente na definição de zonas com potencial produtivo, orientando as intervenções localizadas de fertilizantes e de manejo do solo.

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