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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.
181

Hastes instrumentadas com controle automatizado do escarificador atuando em profundidades variáveis

Machado, Thiago Martins [UNESP] 14 June 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-06-14Bitstream added on 2014-06-13T21:02:55Z : No. of bitstreams: 1 machado_tm_dr_botfca.pdf: 902673 bytes, checksum: 5e756aa779285eb51954dcbe8f5eeb37 (MD5) / A compactação do solo é um problema que atinge a maioria das áreas agricultáveis do Brasil, sendo provocada por diversos fatores, tais como o excesso de carga e o tráfego intenso de máquinas, uso de pneus inadequados para a carga aplicada e pressões de inflação fora do recomendado, tráfego de máquinas no campo com o teor de água do solo não recomendado e vários outros problemas. Existem disponíveis vários modelos e sistemas de medição da compactação do solo no Brasil; porém, os sensores desses equipamentos necessitam de processamento e interpretação dos dados. O objetivo deste trabalho foi projetar e avaliar um protótipo de hastes instrumentadas para identificar as camadas compactadas dos solos agrícolas em tempo real e em profundidades variáveis. O equipamento foi desenvolvido para ser montado na parte frontal do trator “tendo o movimento vertical, para introdução no solo”, controlado pelo sistema hidráulico central do trator. As partes constituintes do protótipo frontal são o chassi, hastes, células de carga, coletor de dados, GPS, sensor de posição e controlador de fluxo de óleo que comanda o escarificador, acoplado na traseira do trator que é utilizado para descompactar o solo. O protótipo frontal do trator envia os dados de tensão do solo lidos pelas células de carga, sendo armazenados e sincronizados com os arquivos vindos do GPS e enviados por um coletor de dados, ao controlador de fluxo de óleo do escarificador, de acordo com os dados do sensor de posição, considerando o limite de tensão programado para que o escarificador atue, ou seja, penetre no solo na profundidade indicada, quando for maior ou igual a 2 MPa, promovendo a movimentação vertical do escarificador quando necessário. A calibração... / The soil compaction is a problem that affects most of agriculture fields in Brazil, aggravated for many factors, for example excess weight in the traffic and intense traffic machinery, tires used inadequately for the load weight applied and calibration pressures not recommended, the machineries enters on the field with water content in soil not recommended, and there are others problems. There are several models and systems available to measure the compaction in the soil in Brazil, but the data of equipment sensors need to be interpreted and processed. The objective of this work was to design and evaluate a prototype to indentify the compacted layers in the agricultural soil in real time and on the go in various depths. The equipment was design to be mounted in front of the tractor with vertical movement, to be introduced in the soil, controlled by central hydraulic system of the tractor. The constituent parts of frontal sensor are chassis, tines, load's cells, electronic system to collect files, GPS, position sensors, and oil flow controllers that transfers the command to the chiseled that is mounted behind the tractor and is used to mobilize the soil. The frontal sensor of tractor feeds together with the GPS files the pressure files of the soil read by load cells and this files are stored and sent by one data collector and to controller's oil flow of chisel according by positions sensor considering the programmed limit to the moves of chisel. In other words introduce the soil in initial depth if the pressure is equal or bigger than 2 MPa for initiate the vertical movement of the chisel, when needed. The equipment's calibration was made in area from the NEMPA's test track - Núcleo de Ensaio de Máquinas e Pneus Agrícolas - used as calibrator of the detector equipment of compaction a penetrometer and the Cone Index (IC) was inserted in the data... (Complete abstract click electronic access below)
182

Agricultura de precisão por metodologia geoestatística: aplicação em solo do Estado de Rondônia

Nascimento, Gerson Flôres [UNESP] 05 September 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-05Bitstream added on 2014-06-13T19:21:49Z : No. of bitstreams: 1 nascimento_gf_dr_rcla.pdf: 1247848 bytes, checksum: 89c8f2950afff4ac2857fc4e72433047 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve por objetivo verificar a variabilidade espacial de atributos químicos do solo, referentes à macronutrientes utilizando métodos estatísticos e geoestatísticos, em uma área considerada homogênea, contendo campo com pastagem e área de floresta. A área escolhida foi a da Fazenda Mata Verde, situada no município de Candeias do Jamari – RO, a cerca de 30 km da capital. Na fase inicial da pesquisa foi elaborado um plano amostral, a partir de uma préamostragem georreferenciada, que resultou na determinação do tamanho da amostra para cada uma das áreas estudadas, cuja opção foi coletar 130 amostras no perfil 00,20 m distribuídas em malha quadrada para cada uma das áreas. Os dados foram analisados em duas fases: análise química e análise estatística. A análise química das amostras foi realizada para identificar os teores de alumínio (Al), cálcio (Ca), matéria orgânica (MO) e potencial de hidrogênio (pH). Para a realização da análise quantitativa, os valores resultantes da análise química foram armazenados em planilhas eletrônicas com os respectivos posicionamentos geográficos. Na análise descritiva e inferências estatísticas clássicas, foram efetuados os cálculos da média, variância, desvio padrão, coeficiente de variação, coeficiente de assimetria e coeficiente de curtose, dos dados amostrados. Foram ajustados modelos teóricos de variogramas aos dados experimentais e realizado o teste de validação cruzada, bem como a construção de mapas de atributos de solo, fazendo uso de krigagem ordinária. A partir dos resultados obtidos, foi possível concluir que a ocorrência de disparidades nos mapas dos atributos Al, Ca, MO e pH, nas áreas estudadas, é um indicativo da necessidade de adoção de metodologias diferenciadas para uso da área de pastagem, considerando o manejo adotado pelo pecuarista. / The purpose of this work is to verify spatial variability of soil’s macro nutrients chemical attributes using statistical and geostatistical tools, in an area considered homogeneous containing pasture and forest. The chosen area was the Mata Verde Farm situated in Candeias do Jamari City – Rondonia State, distant 30 km from the State capital. In the initial stage a sampling plan was elaborated based upon a georeferencing presampling. This resulted in sample sizes for each one of studied areas. The chosen option was the collect of 130 samples in soil profile 00.20 m grid distributed for each one of the areas. The data was analyzed in two phases: chemical analysis and statistical analysis. The samples’ chemicals analysis were done to identify macronutrients contents Al, Ca, organic matter (MO) and pH and the values of the chemical analysis were recorded in spreadsheets with respective geographic positions. To descriptive analysis and classic statistical inferences were carried out calculating means, variance, standard deviation, variation coefficient, asymmetry coefficient and kurtosis coefficient of sampled data. The theoretic model of variograms were adjusted to experimental data and carried out a cross validation test, as well as the maps construction of soil attributes using ordinary kriging. From results was possible to conclude that the occurrence of disparities in spatial distribution maps of aluminum, calcium, organic matter and pH in studied areas is an indicative of necessity of adoption of differentiated methodologies for use of the pasture area, considering the management adopted by the cattle farmers.
183

Developing a dealer customer support center strategy

Hauger, Jarah January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Vincent R. Amanor-Boadu / As the integration of technology and data rises in production agriculture, John Deere dealers in North America are in a constant quest to differentiate themselves and be more than just an equipment provider. Customers with more technologically advanced products are requiring more support from the dealerships. Each dealership has a unique opportunity to provide unprecedented levels of support and each may do it in a slightly different way. This creates a challenge for Deere & Company in providing resources and support to those dealers in their endeavors. This thesis was requested by Deere & Company (John Deere) to provide the company with information on Dealer Customer Support Centers in North America. In order to provide resources and tools for dealers to be successful, it is necessary to understand what they are currently doing with customer support centers and the barriers to implementing more. An online survey was sent out to the Integrated Solutions Manager at every John Deere Dealer organization in North America. From that survey there were a total of 127 responses. The two most common forms of customer support systems that dealers are using are having Integrated Solutions Staff members take calls directly from customers and having someone within the dealership answer the phone and manually route the call to the right person for support. Data also shows that some of the less common but more technologically advanced methods of support have been implemented more in the past 12 months. Survey analysis indicates that only a small percentage of dealers have a true centralized dedicated support center for customers. This subset of dealers is utilizing several different methods to support customers. The two indicative methods are having a 1- 800 number for customers to utilize for support and having a dedicated staff to help customers remotely. Dealers are frequently using several types of tools and resources to help support customers, the most frequently occurring ones include JDLink™ and Data Management Services. Respondents indicated using many other tools to provide value to customers including John Deere Remote Display Access, clinics and optimization sessions and many others. Barriers to implementing more complex forms of customer support are numerous, the biggest of which is the cost of implementation and lack of resources to support a more sophisticated customer support system. With this information, John Deere is better positioned to provide resources and support to our dealer channel facing these challenges.
184

Value of map sharing between multiple vehicles in the same field while using automated section control

Bennett, Jeffrey D. January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Terry Griffin / Large acreage farms and even moderate sized farms employing custom applicators and harvesters have multiple machines in the same field at the same time conducting the same field operation. As a method to control input costs and minimize application overlap, these machines have been equipped with automatic section control (ASC). For nearly all these multiple-vehicle operations, over application is a concern especially for more irregularly shaped fields; however modern technology including automated guidance combined with automatic section control allow reduced doubling of input application including seeds, fertilizer, and spray. Automatic section control depends on coverage maps stored locally on each vehicle to determine whether or not to apply input products and up to now, there has not been a clear method to share these maps between vehicles in the same field. Without sharing coverage maps, an individual ASC planting unit only has location data where it has applied individually and no location data for where other planting units have applied seed in that same field. Automatic section control relies upon shared coverage maps to be continually updated between each planting unit and utilizes existing machine telematics infrastructure for map data sharing. Telematics utilizes a cloud computing platform and cellular connectivity which in rural areas is known to have limited service levels. Planting operations were simulated for two 16-row planters, each using two John Deere GreenStar3 2630 monitors, simulated GPS location data stream, electronic rate control units, and individual row unit clutches to have control at the finest granularity. Each simulated planting unit is equipped with automatic section control and telematics gateways to share coverage map data from the first planting unit to JDLink cloud infrastructure then out to the second. This study evaluates the impact that field size and shape have on using multiple ASC planters and coverage map sharing, and estimates seed cost savings from reducing over application because coverage maps are shared between planting units. The impact of sharing coverage maps with both planting units using field boundaries with automatic section control and without using field boundaries were evaluated. Guidance line headings were determined using AgLeader SMS’s mission planning feature to minimize the number of passes across each field based on the field boundary and implement width. Each field was run twice using parallel tracking, once each with and without coverage map sharing to observe the extent of over application. The field level data were then taken to examine a fictious 3,000 acre farming operation where the field level data was used as a partial composition of the farm operation. An embedded Microsoft Excel macro was used to create 8,008 different composition scenarios to determine farm level savings. The average farm savings was $58,909 per year. Additionally, using the 8,008 scenarios, time value of money was examined to determine the the minimum area required annually for five years for this technology to pay back. The average was 133 acres each year for five years. Equipment manufacturers and farmers have interest in these results. In general, equipment manufacturers desire to create a service-based product to be sold such that continual revenue path provides value added services after the precision agriculture hardware is sold. In this study, the existing telematics product offerings are tied to shared coverage maps to provide a value-add to an existing service. Farmers want to ensure this is a sound equipment investment with payback in a relatively short time period. As farm input costs continue to rise especially relative to crop prices, reducing over application will be critical to limit waste.
185

Evaluation of optical sensor technologies to optimize winter wheat (Triticum aestivum L.) management

Lorence, Ashley Abigail January 1900 (has links)
Master of Science / Department of Agronomy / Antonio R. Asebedo / Sensor technology has become more important in precision agriculture, by real time sensing for site specific management to monitor crops during the season especially nitrogen (N). In Kansas N available in the soils can vary year to year or over a course of a year. The objective of this study was to compare current available passive (PS) and active optical sensor technologies (AOS) performance in regards to sky conditions effects and derive the NDVI (normalized difference vegetation index) relationship to wheat yield, as well as evaluate KSU optical sensor-based N recommendations against KSU soil test N recommendation system and sUAS (small unmanned aircraft systems) based recommendation algorithms with the PS and AOS platforms. Each year (2015-2016 & 2016-2017) five field trails across Kansas were conducted during the winter wheat crop year in cooperation with county ag agents, farmers, and KSU Agronomy Experiment Fields. Treatments consisted of N response curve, 1st and 2nd generation KSU N recommendation algorithms, sUAS based recommendation algorithms, and KSU soil test based N recommendations applied in the spring using N rates ranging from 0 to 140 kg ha⁻¹. Results indicate the Holland Scientific Rapid Scan and MicaSense RedEdge NDVI data was strongly correlated and generated strong relationships with grain yield at 0.60 and 0.57 R² respectively. DJI X3 lacks an NIR band producing uncalibrated false NDVI and no relationship to grain yield at 0.03 R². Calibrated NDVI from both sensors are effective for assessing yield potential and could be utilized for developing N recommendation algorithms. However, sensor based treatments preformed equal to higher yields compared the KSU soil test recommendations, as well as reduced the amount of fertilizer applied compared to the soil test recommendation. The intensive management algorithm was the most effective in determining appropriate N recommendations across locations. This allows farmers to take advantage of potential N mineralization that can occur in the spring. Further research is needed considering on setting the NUE (nitrogen use efficiency) in KSU N rec. algorithms for effects of management practice, weather, and grain protein for continued refinement.
186

Variabilidade espacial de atributos do solo e da produtividade de soja

Beraldo, José Marcos Garrido [UNESP] 30 June 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-06-30Bitstream added on 2014-06-13T19:16:31Z : No. of bitstreams: 1 beraldo_jmg_me_jabo.pdf: 650280 bytes, checksum: 1d6c7c599f6098080536b0c3fe64624a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve como objetivo avaliar a distribuição espacial de atributos do solo antes e após a aplicação em doses variadas de calcário e fertilizante fosfatado e estudar as correlações entre os atributos químicos e físicos do solo com a produtividade da soja. Foram coletadas amostras de solo geo-referenciadas na intensidade de uma amostra por hectare na profundidade de 0-0,20 m em três talhões. Foram determinados: pH, teores de matéria orgânica, P, K, Ca, Mg, H+Al, textura do solo e calculado a CTC e o V%. O solo foi corrigido com calcário e fertilizado com adubo fosfatado, utilizando uma distribuidora dotada de um sistema para aplicação em doses variadas, procedendo-se a semeadura da soja. A colheita foi monitorada utilizando uma colhedora equipada com um monitor de produtividade. Após a colheita coletou-se amostras de solo nos mesmos pontos de amostragem. Os dados foram analisados com análise estatística descritiva e geoestatística. O manejo do solo através da aplicação variada de calcário e fósforo diminuiu a variabilidade espacial dos teores de P e os valores de V%. O P foi o atributo do solo que mais se correlacionou com a produtividade da soja. O mapa de produtividade possibilitou identificar onde as baixas e altas produtividades estão localizadas na área. / The objective of this work was to evaluate soil properties maps developed by different methods, before and after lime and phosphorus fertilizer application at variable rates, using geoestatistics techniques to develop maps showing spatial dependence of soil properties, and relationship chemical and physical attributes of the soil with the production of soybean. Soil georeferenced samples were obtained at from 0 - 0,20 m depths in three fields. P, Ca, Mg, K, H+Al, pH, CEC, texture and base saturation (V%) were determined in each sample. Lime and phosphorus requirement were calculated to increase the base saturation to 70% and phosphorus level to 40 mg dm-3. Prescription lime and phosphorus maps were developed using the SSToolbox program. Based on these maps, lime and phosphorus fertilizer were applied at variable rates. The harvest of a soybean yield was monitored continuously using a harvest machine equipped with a real-time global positioning system unit (GPS) for yield monitoring. After a soybean growing season the soil was sampled again at the same points, and condition maps after variable rate application. Lime and phosphorus, were developed using the SSToolbox program and geoestatistics parameters. Descriptive statistics of soil data were calculated and geostatistical analysis were performed to mesure and model the spatial variability of soil properties. The results showed that the maps developed using SSToolbox program and geoestatistics parameters were similar. Lime and phosphorus variable rate application reduced the spatial variability of base saturation and phosphorus level in the experimental area. The yield map allowed to identify the location of the high and low soybean yield in the area.
187

Densidade de amostragem de dados para análise da correlação espacial da produtividade do eucalipto em função de atributos do solo / Density for analysis of space correlation of eucalyptus productivity in the function of soil attributes

Corrêa, Adriany Rodrigues 02 March 2018 (has links)
Submitted by ADRIANY RODRIGUES CORRÊA (adriany@agronoma.eng.br) on 2018-04-27T21:15:18Z No. of bitstreams: 1 Adriany Rodrigues Corrêa.pdf: 2537499 bytes, checksum: 5f019ab13b90f73e544050f3efa14a28 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-05-02T13:59:01Z (GMT) No. of bitstreams: 1 correa_ar_dr_ilha.pdf: 2537499 bytes, checksum: 5f019ab13b90f73e544050f3efa14a28 (MD5) / Made available in DSpace on 2018-05-02T13:59:01Z (GMT). No. of bitstreams: 1 correa_ar_dr_ilha.pdf: 2537499 bytes, checksum: 5f019ab13b90f73e544050f3efa14a28 (MD5) Previous issue date: 2018-03-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Um dos fatores limitantes para o uso da agricultura de precisão é o número de amostras necessárias para representar espacialmente a distribuição do nutriente ou insumo aplicado de forma variada. Portanto objetivou-se com a presente pesquisa avaliar com base na análise geoestatística o número ideal de subamostras para compor uma composta que melhor determine as zonas específicas de manejo e ratificar a existência de um atributo (solo e/ou planta) que possa, espacialmente, funcionar como indicador de qualidade, isto é, caracterizar as zonas específicas de manejo, com o intuito de aumentar a produtividade do Eucalyptus camaldulensis com sete anos de idade. O estudo foi desenvolvido em 2015, na Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia de Ilha Solteira – UNESP, em Selvíria (MS, Brasil), latitude 20° 20’ 31” S, longitude 51° 24’ 12” W. Para tanto, foram analisadas as correlações lineares e espaciais entre atributos do eucalipto e de um LATOSSOLO VERMELHO Distrófico, os quais foram: circunferência à altura do peito (CAP), altura da árvore (ALT), o volume médio anual de madeira com a casca (VOL), densidade do solo (DS), resistência do solo à penetração (RP), teor umidade gravimétrica (UG), porosidade total (PT), potencial hidrogeniônico (pH), matéria orgânica (MO) e estoque de carbono (EC). Foi instalada uma malha geoestatística com 120 pontos, sendo constituída de seis transeções paralelas (sentido N-S), espaçadas em 14 m, com 20 pontos amostrais cada, espaçados em 18 m, deixando uma bordadura de 10 m. Com três composições amostrais, sendo a composição amostral de um único dado (CA1), composição amostral com média de cinco dados (CA5) e composição amostral com média de dez dados (CA10). O volume da madeira pôde ser estimado por meio da cokrigagem com a resistência a penetração do solo, ratificando assim a RP como um atributo potencial para atuar como indicador de qualidade visando o aumento da produtividade da madeira. Do ponto de vista espacial a Composição Amostral com Média de Dez Dados (CA10): apresentou-se como a mais satisfatória, sendo a única capaz de caracterizar a variabilidade dos atributos do Eucalyptus camaldulensis, possibilitando criar mapas relacionando-se com o solo, podendo determinar as zonas específicas de manejo. / One of the limiting factors for the use of precision agriculture is the number of samples needed to spatially represent the distribution of the nutrient or input applied in a varied way. Therefore, the objective of this research was to evaluate the ideal number of subsamples to compose a composite that better determines the specific areas of management and ratify the existence of an attribute (soil and / or plant) that can, spatially, to function as a quality indicator, that is, to characterize the specific areas of management, in order to increase the productivity of Eucalyptus camaldulensis at seven years of age. The study was conducted in 2015, at the UNESP - São Paulo State University, in Selvíria (MS, Brazil), latitude 20 ° 20 '31 "S, longitude 51 ° 24' 12" W. In order to do so, we analyzed the linear and spatial correlations between eucalyptus attributes and a Distrofic RED LATOSOLO, which were: circumference at breast height (CBH), height of the tree (HT), mean annual volume of wood with bark (VOL), soil bulk density (SB), soil penetration to resistance (PR), gravimetrical moisture contents (GM), total porosity (TP), hydrogenation potential (pH), organic matter (OM) and carbon stock content (CS). A geostatistical mesh was installed with 120 points, consisting of six parallel transects (N-S direction), spaced at 14 m, with 20 sample points each, spaced at 18 m, leaving a 10 m border. With three sample compositions, the sample composition of a single data (CA1), sample composition with a mean of five data (CA5) and sample composition with a mean of ten data (CA10). The volume of the wood could be estimated by means of cokriging with resistance to soil penetration, thus confirming the PR as a potential attribute to act as a quality indicator aiming at increasing wood productivity. From the spatial point of view, the Composition Sampling with Average of ten data (CA10): presented the most satisfactory, being the only one able to characterize the variability of the attributes of Eucalyptus camaldulensis, making it possible to create maps relating to the soil, specific management areas.
188

Atributos do solo e componentes produtivos da soja: Uma abordagem linear, multivariada e geoestatística /

Lovera, Lenon Henrique. January 2015 (has links)
Orientador: Rafael Montanari / Co-orientador: Alan Rodrigo Panosso / Banca: Marcelo Andreotti / Banca: Zigomar Menezes de Souza / Resumo: O estudo dos atributos do solo e da planta utilizando a geoestatística, e a consequente geração de mapas de krigagem, resultam na utilização racional de fertilizantes e, assim na redução de custos para o produtor. No ano agrícola de 2013/2014, no município de Selvíria (MS), objetivou-se avaliar a dependência espacial e a análise multivariada dos atributos físicos, químicos, teores de nutrientes foliares e macrofauna de um Latossolo Vermelho distroférrico em duas profundidades, com os componentes da produção e produtividade de grãos cultivada em sistema plantio direto. Foi instalada uma malha amostral, para a coleta de dados do solo, planta e macrofauna, com 100 pontos amostrais distribuídos aletoriamente, em uma área de 7980 m 2 . As maiores variabilidades dos atributos analisadas pelo coeficiente de variação ocorreram na camada de 0,00-0,10 m do solo. Alguns dos atributos pesquisados apresentaram dependência espacial, sendo possível mapear a área em estudo. Os valores dos alcances geoestatísticos recomendados para os atributos pesquisados deverão estar compreendidos entre 9,9 e 91,8 m. Espacialmente falando, a produtividade de grãos da soja pôde ser estimada por meio da co-krigagem com o valor do DS2, DMG, DMP do solo e fósforo foliar. Assim, valores baixos e altos destes atributos indicaram sítios com as maiores ou menores produtividades de grãos e soja. A análise multivariada permitiu que apenas alguns atributos se destacassem como componentes principais, sendo considerados os mais importantes para o manejo do solo dessa área / Abstract: The study of soil properties and plant using geostatistics, and the subsequent generation of kriging maps result in the rational use of fertilizers and thus to reduce costs for producers. In the agricultural year 2013/2014, in Selvíria (MS) aimed to evaluate the spatial dependency and multivariate analysis of physical, chemical attributes, foliar nutrient content and macrofauna of Oxisol in two depths, with yield components and grain yield grown in no-till system. A sampling grid was installed to collect soil data, plant and macrofauna, with 100 sampling points distributed random, in an area of 7980 m 2 . The greatest variability of the attributes analyzed by the coefficient of variation occurred at a depth of 0.00 to 0.10 m above the ground. Some of the attributes studied presented spatial dependence, it is possible to map the area under study. The values of geostatistical ranges recommended for the surveyed attributes should be between 9,9 and 91,8 m. Spatially speaking, the productivity of the soybeans could be estimated by means of co-kriging with the value DS2, DMG, DMP soil and foliar phosphorus. So, low and high values of these attributes indicate sites with higher or lower yields of grain and soybeans. Multivariate analysis has allowed only a few attributes to stand out as main components, being considered the most important for soil management in this area / Mestre
189

Variabilidade espacial de atributos do solo e da produtividade de soja /

Beraldo, José Marcos Garrido. January 2004 (has links)
Orientador: José Eduardo Corá / Banca: José Paulo Molin / Banca: Gener Tadeu Pereira / Resumo: O presente trabalho teve como objetivo avaliar a distribuição espacial de atributos do solo antes e após a aplicação em doses variadas de calcário e fertilizante fosfatado e estudar as correlações entre os atributos químicos e físicos do solo com a produtividade da soja. Foram coletadas amostras de solo geo-referenciadas na intensidade de uma amostra por hectare na profundidade de 0-0,20 m em três talhões. Foram determinados: pH, teores de matéria orgânica, P, K, Ca, Mg, H+Al, textura do solo e calculado a CTC e o V%. O solo foi corrigido com calcário e fertilizado com adubo fosfatado, utilizando uma distribuidora dotada de um sistema para aplicação em doses variadas, procedendo-se a semeadura da soja. A colheita foi monitorada utilizando uma colhedora equipada com um monitor de produtividade. Após a colheita coletou-se amostras de solo nos mesmos pontos de amostragem. Os dados foram analisados com análise estatística descritiva e geoestatística. O manejo do solo através da aplicação variada de calcário e fósforo diminuiu a variabilidade espacial dos teores de P e os valores de V%. O P foi o atributo do solo que mais se correlacionou com a produtividade da soja. O mapa de produtividade possibilitou identificar onde as baixas e altas produtividades estão localizadas na área. / Abstract: The objective of this work was to evaluate soil properties maps developed by different methods, before and after lime and phosphorus fertilizer application at variable rates, using geoestatistics techniques to develop maps showing spatial dependence of soil properties, and relationship chemical and physical attributes of the soil with the production of soybean. Soil georeferenced samples were obtained at from 0 - 0,20 m depths in three fields. P, Ca, Mg, K, H+Al, pH, CEC, texture and base saturation (V%) were determined in each sample. Lime and phosphorus requirement were calculated to increase the base saturation to 70% and phosphorus level to 40 mg dm-3. Prescription lime and phosphorus maps were developed using the SSToolbox program. Based on these maps, lime and phosphorus fertilizer were applied at variable rates. The harvest of a soybean yield was monitored continuously using a harvest machine equipped with a real-time global positioning system unit (GPS) for yield monitoring. After a soybean growing season the soil was sampled again at the same points, and condition maps after variable rate application. Lime and phosphorus, were developed using the SSToolbox program and geoestatistics parameters. Descriptive statistics of soil data were calculated and geostatistical analysis were performed to mesure and model the spatial variability of soil properties. The results showed that the maps developed using SSToolbox program and geoestatistics parameters were similar. Lime and phosphorus variable rate application reduced the spatial variability of base saturation and phosphorus level in the experimental area. The yield map allowed to identify the location of the high and low soybean yield in the area. / Mestre
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Agricultura de precisão por metodologia geoestatística : aplicação em solo do Estado de Rondônia /

Nascimento, Gerson Flôres. January 2008 (has links)
Orientador: Paulo Milton Barbosa Landim / Banca: Célia Regina Lopes Zimback / Banca: Dilermando Perecin / Banca: Marcelo Monteiro da Rocha / Banca: Roberto Wagner Lourenço / Resumo: O presente trabalho teve por objetivo verificar a variabilidade espacial de atributos químicos do solo, referentes à macronutrientes utilizando métodos estatísticos e geoestatísticos, em uma área considerada homogênea, contendo campo com pastagem e área de floresta. A área escolhida foi a da Fazenda Mata Verde, situada no município de Candeias do Jamari - RO, a cerca de 30 km da capital. Na fase inicial da pesquisa foi elaborado um plano amostral, a partir de uma préamostragem georreferenciada, que resultou na determinação do tamanho da amostra para cada uma das áreas estudadas, cuja opção foi coletar 130 amostras no perfil 00,20 m distribuídas em malha quadrada para cada uma das áreas. Os dados foram analisados em duas fases: análise química e análise estatística. A análise química das amostras foi realizada para identificar os teores de alumínio (Al), cálcio (Ca), matéria orgânica (MO) e potencial de hidrogênio (pH). Para a realização da análise quantitativa, os valores resultantes da análise química foram armazenados em planilhas eletrônicas com os respectivos posicionamentos geográficos. Na análise descritiva e inferências estatísticas clássicas, foram efetuados os cálculos da média, variância, desvio padrão, coeficiente de variação, coeficiente de assimetria e coeficiente de curtose, dos dados amostrados. Foram ajustados modelos teóricos de variogramas aos dados experimentais e realizado o teste de validação cruzada, bem como a construção de mapas de atributos de solo, fazendo uso de krigagem ordinária. A partir dos resultados obtidos, foi possível concluir que a ocorrência de disparidades nos mapas dos atributos Al, Ca, MO e pH, nas áreas estudadas, é um indicativo da necessidade de adoção de metodologias diferenciadas para uso da área de pastagem, considerando o manejo adotado pelo pecuarista. / Abstract: The purpose of this work is to verify spatial variability of soil's macro nutrients chemical attributes using statistical and geostatistical tools, in an area considered homogeneous containing pasture and forest. The chosen area was the Mata Verde Farm situated in Candeias do Jamari City - Rondonia State, distant 30 km from the State capital. In the initial stage a sampling plan was elaborated based upon a georeferencing presampling. This resulted in sample sizes for each one of studied areas. The chosen option was the collect of 130 samples in soil profile 00.20 m grid distributed for each one of the areas. The data was analyzed in two phases: chemical analysis and statistical analysis. The samples' chemicals analysis were done to identify macronutrients contents Al, Ca, organic matter (MO) and pH and the values of the chemical analysis were recorded in spreadsheets with respective geographic positions. To descriptive analysis and classic statistical inferences were carried out calculating means, variance, standard deviation, variation coefficient, asymmetry coefficient and kurtosis coefficient of sampled data. The theoretic model of variograms were adjusted to experimental data and carried out a cross validation test, as well as the maps construction of soil attributes using ordinary kriging. From results was possible to conclude that the occurrence of disparities in spatial distribution maps of aluminum, calcium, organic matter and pH in studied areas is an indicative of necessity of adoption of differentiated methodologies for use of the pasture area, considering the management adopted by the cattle farmers. / Doutor

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