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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Reestruturação produtiva e qualificação profissional : um estudo de caso sobre a cadeia do fumo /

Faria, Andréia Farina de. January 2010 (has links)
Orientador: Leila de Menezes Stein / Banca: Fabiane Santana Previtalli / Banca: Darlene Aparecida de Oliveira Ferreira / Resumo: A dissertação busca retratar a dinâmica da cadeia produtiva do fumo. O objetivo geral envolve dois aspectos: discutir a reestruturação produtiva do setor que se estende do campo à produção fabril, e problematizar a qualificação profissional dos trabalhadores envolvidos na cadeia do fumo, visto que se trata de uma cadeia coordenada por multinacionais que detém as inovações tecnológicas utilizadas ao longo da cadeia produtiva do fumo/cigarro. O objetivo específico é discutir tais aspectos a partir de um estudo de caso, envolvendo a empresa Souza Cruz S/A, visto que esta está presente nos dois ramos da produção, ou seja, na produção agrícola integrada e na fabricação de cigarros. O controle da cadeia se dá então de forma específica, coordenada por uma política integrada, denominada Supply Chain, na qual a ausência de qualificação profissional no campo torna-se um instrumento de controle no campo, ao passo que na indústria o discurso da qualificação profissional aumenta a intensificação do trabalho na fábrica. Ademais também caracterizamos uma nova forma de relação interfirmas existente entre empresas fumageiras, empresas agro-químicas e agricultores integrados. O estudo de caso realizado no ano de 2009 deu-se a partir de entrevistas com agricultores e entidades representativas localizadas no município de Santa Cruz do Sul/RS (maior complexo fumageiro do mundo). A pesquisa realizada na unidade produtiva da Souza Cruz S/A em Uberlândia/MG deu-se durante o ano de 2008 e compreende o período 1990-2007 no qual a empresa implementou seu projeto de reestruturação produtiva. / Abstract: Not available / Mestre
12

Proposta de método de controle integrado entre produção e qualidade com mensuração de perdas por making-do e pacotes informais

Fireman, Marcus Costa Tenorio January 2012 (has links)
O controle de perdas tem sido apontado como uma das principais estratégias para melhoria do desempenho e para redução de custos de sistemas de produção. Entretanto, apesar de sua importância, este é um tema pouco abordado na literatura sobre gestão da construção, principalmente no que se refere a sistemas de controle da produção. Alguns estudos recentes chamaram a atenção para a existência de uma perda típica do setor, denominada de making-do, a qual pode ser definida como a redução de desempenho do sistema produtivo devido à execução de atividades em condições subótimas. Este tipo de perda ainda tem sido apontada como uma das causas fundamentais de problemas da qualidade, e de outras perdas, tais como retrabalho e trabalho em progresso. Falhas na análise de restrições realizadas no planejamento de médio prazo têm sido apontadas como a principal razão para o surgimento de perdas por making-do, pois na ausência dos requisitos necessários para execução das atividades normalmente as equipes realizam improvisações, que podem afetar o desempenho da produção. O presente trabalho propõe um método de controle integrado produção e qualidade que permita mensurar perdas por making-do e também a ocorrência de pacotes de trabalho informais. Este método está dividido em três módulos: (a) identificação de perdas por making-do; (b) identificação de pacotes informais; e (c) controle integrado produção e qualidade. O desenvolvimento da pesquisa foi dividido nas seguintes etapas: (a) compreensão do problema; (b) estruturação do método; (c) consolidação do método; (d) avaliação dos resultados e proposição do método final. Como principais contribuições do trabalho, além do próprio método proposto, o estudo propõe uma conceitualização de perdas por making-do, retrabalho e falta de terminalidade. Ainda, os resultados demonstram a existência de uma forte relação entre as perdas por making-do, a execução de pacotes informais e o aumento do trabalho em progresso. / Waste control has been pointed out as one of the key strategies for improving the performance and reducing costs of production systems. However, despite its importance, this is a topic poorly discussed in the construction management literature, especially in relation to production control systems. Some recent studies have called the attention for a type of waste that is typical of the construction sector, named making-do, which can be defined as a loss in performance due to the execution of activities in sub-optimal conditions. It has been suggested that this type of waste is one of the root causes of quality failures, and also of other types of waste, such as rework and work in progress. Failures in constraint analysis at the medium term planning level have been pointed out a major cause of makingdo waste, as the crews tend to improvise when faced with the lack of prerequisites for the execution of tasks, which may affect the production performance. This research work proposes a method for integrated production and quality control, which enables the measurement making-do waste and also the occurrence of informal work packages This method is divided into three modules: (a) identification of making-do waste; (b) identification of informal work packages; and (c) integrated and production and quality control. The development of this research work was divided into the following stages: (a) understanding the problem; (b) structuring the method; (c) consolidating the method; (d) evaluation of results and proposition of the final version of the method. As main contributions, besides the integrated control method, this investigation proposes a conceptualization for three categories of waste: making-do, rework, and unfinished work. Moreover, the results indicate that there is a strong relationship making-do waste, the execution of informal packages and the increase of work in progress.
13

As Comunidades rurais e o seu novo significado como lugar a partir da introdução dos sistemas de produção integrada em Orleans - SC

Antunes, Marcio Fenili January 2006 (has links)
Esta pesquisa examina o significado e o papel que as comunidades rurais do interior do município de Orleans assumiram na região Sul de Santa Catarina tendo em vista a penetração e expansão dos sistemas de produção integrada, especialmente de frangos. Resgata os conceitos de região, território e lugar para analisar os processos de formação territorial e a importância da técnica para o estabelecimento das relações do homem com o seu meio. As comunidades são tomadas como lugares, caracterizados neste trabalho em dois momentos históricos: o início de sua formação, época dos primeiros imigrantes e o tempo atual, após as transformações sofridas pela penetração da fumicultura, da suinocultura e da avicultura integrada. O objetivo é revelar um novo lugar, seja pelo papel que exercem estas comunidades nas atuais redes de produção e comércio, seja pelas novas relações que seus moradores estabelecem com o meio. / This research examines the meaning and the role that rural communities of the countryside of the town of Orleans took in the South Region of Santa Catarina, focusing on the penetration and expansion of the systems of integrated production, especially concerning chicken. It brings back the concepts of region, territory and place to analyze the processes of territorial formation and the importance of the technique for the establishment of the relationship among men and its environment. The communities are taken as places, characterized in this paper in two historical moments: the beginning of its formation, time of the first immigrants and nowadays, after the transformation occurred through the penetration of the tobacco culture, the pig-raising and the integrated aviculture. The aim of this paper is to reveal a new place, either for the role this communities play in the current production nets and commerce or for its new relations that the inhabitants establish with the environment.
14

Dinâmica dos gases de efeito estufa do sistema solo-planta em sistemas de integração / Greenhouse gas dynamics in the soil-plant system in integrated systems

Milene Gondim de Oliveira Alves 17 August 2017 (has links)
A agricultura está relacionada à concentração atmosférica de gases de efeito estufa (GEE) através dos processos básicos que ocorrem no sistema solo-planta. Mudanças no uso e manejo do solo podem causar tanto efeito negativo como positivo no que se refere à emissão de gases de efeito estufa para a atmosfera. O objetivo deste trabalho foi avaliar o fluxo de óxido nitroso e metano em diferentes sistemas de produção agropecuários e na vegetação natural durante as estações do ano, analisando os fatores edafoclimáticos que influenciam as emissões desses gases de efeito estufa. O experimento foi desenvolvido na Empresa Brasileira de Pesquisa Agropecuária, na cidade de São Carlos - SP (21 ° 57\'S, 47 ° 50\'W), no período de outubro de 2013 a agosto de 2014, onde se avaliou o fluxo de gases de efeito estufa em todas as estações do ano. Foram avaliadas as emissões de óxido nitroso (N2O) e metano (CH4) das pastagens pelo solo dos sistemas de integração lavoura-pecuária floresta - ILPF, integração lavoura-pecuária - ILP, silvipastoril - IPF, pastagem sob manejo intensivo - INT, pastagem sob manejo extensivo - EXT e a vegetação natural (Floresta Estacional Semidecidual do Bioma Mata Atlântica) - Floresta. O delineamento experimental foi em blocos ao acaso com repetições. Foram usadas duas repetições para cada área de pastagem, que consistiram nos blocos. Os fluxos líquidos de emissão de óxido nitroso e metano foram coletados de amostras de ar provenientes de \"câmaras estáticas\", seis por tratamento, sendo três câmaras (repetições) por bloco (área de pastagem ou parcelas na floresta) em cada amostragem. As coletas das amostras gasosas foram feitas em três tempos (0, 30 e 60 minutos) durante 10 dias em cada estação do ano (meados) e analisadas por cromatografia gasosa. Simultaneamente às coletas de gases, coletaram-se amostras de solo em áreas adjacentes para determinação dos teores de N-total, N-NH+4 e N-NO-3 e da umidade gravimétrica. Nessas amostras foram mensuradas a fertilidade do solo, as densidades aparente e de partícula do solo e a porcentagem do espaço poroso do solo ocupado por água. Nas taxas de emissões de metano, os sistemas de produção intensivo e extensivo tiveram as maiores contribuições, ambos com uma emissão média diária de 0,067g de CH4 ha-1 d-1. O verão foi a estação do ano que apresentou a maior emissão de metano, com uma taxa média de 0,110 g CH4 ha-1 d-1. Em relação ao óxido nitroso, os sistemas de iLP e intensivo, apresentaram os menores índices de emissão, 0,007 g de N2O ha-1 d-1. Entre as estações do ano, não houve diferença estatística na emissão média de N2O. Dentre as variáveis edafoclimáticas correlacionadas com a emissão dos gases, somente temperatura média e máxima apresentaram correlação significativa com o fluxo de N2O ha-1 d-1 e para o metano, temperatura média e mínima, umidade relativa do ar, precipitação, espaço poroso do solo, amônio e nitrato do solo obtiveram correlação com a emissão de CH4 ha-1 d-1, entretanto as correlações foram muito fracas. Houve interação entre as estações do ano e os sistemas de produção para os fluxos dos gases de efeito estufa. As emissões de metano e óxido nitroso foram bastante baixas em todos os sistemas de produção e na floresta e variaram em função das estações do ano, havendo pequenos fluxos de emissão e, em algumas ocasiões, influxos na dinâmica dos gases metano e óxido nitroso. / Agriculture is related to the atmospheric concentration of greenhouse gases (GHG) through the basic processes that occur in the soil-plant system. Changes in land use and management can cause both negative and positive effects on GHG emission into the atmosphere. The objective of this work was to evaluate the flow of nitrous oxide (N2O) and methane (CH4) in different agricultural production systems and in the natural vegetation during the four seasons, analyzing the edaphoclimatic factors that influence the emissions of these gases. The experiment was carried out at the Brazilian Agricultural Research Corporation, in São Carlos, SP (21 ° 57\'S, 47 ° 50\'W), from October 2013 to August 2014. Nitrous oxide and methane emissions were evaluated in the soil of the crop-livestock-forest (CLF), crop-livestock (CL) and livestock-forest (LF) integrated systems, traditional intensively manged pasture (INT), pasture under extensive management - EXT and the natural vegetation - Seasonal Semideciduous Forest of the Atlantic Forest Biome - FOR. The experimental design was in randomized blocks (two replicates per treatment). Nitrous oxide and CH4 emission net flows were collected from air samples from six \"static chambers\" allocated per treatment (three replicates) per block (pasture area or forest plots) at each sampling. The gas samples were collected three times (0, 30 and 60 minutes) and analyzed by gas chromatography. Simultaneously to the gas sampling, soil samples were collected in adjacent areas to determine N-total, N-NH+4 and N-NO-3 contents and gravimetric moisture. The soil fertility, apparent and particle densities and the percentage of soil porous space occupied by water were measured. In the methane emission rates, intensive and extensive production systems had the highest contributions, both with an average daily emission of 0.067g CH4 ha-1 d-1. Summer was the season with the highest methane emission, with an average rate of 0.110 g CH4 ha-1 d-1. In relation to nitrous oxide, the iLP and intensive systems had the lowest emission rates, 0.007 g of N2O ha-1 d-1. Among the seasons, there was no statistical difference in the mean emission of N2O. Among the edaphoclimatic variables correlated with the gas emission, only mean and maximum temperature showed a significant correlation with the N2O ha-1 d-1 flow and for methane, mean and minimum temperature, relative humidity, precipitation, pore space Soil, ammonium and soil nitrate obtained correlation with the emission of CH4 ha-1 d-1, however the correlations were very weak. There was interaction between the seasons of the year and the production systems for the flows of greenhouse gases. The emissions of methane and nitrous oxide were quite low in all production systems and in the forest and varied according to the seasons, with small emission fluxes and, at times, influxes in the dynamics of methane and nitrous oxide gases.
15

Métodos de solução aplicados ao problema de produção e distribuição / Solution methods applied to production and distribution problem

Henrique Hiroshi Motoyama Watanabe 07 June 2016 (has links)
Neste mestrado estudamos o problema integrado de produção e distribuição (PIPD). Ao resolver o PIPD, tenta-se obter de maneira integrada as decisões de produção, controle de estoque, distribuição e roteamento de veículos. Neste tipo de problema, em cada período, um único ou múltiplos itens são produzidos e distribuídos para os clientes com o objetivo de atender uma determinada demanda a um custo total mínimo. Ou seja, no PIPD deve-se decidir quando e quanto produzir de cada item e as rotas e distribuições de cada veículo tal que o custo final, que inclui custos de produção, estoque e distribuição, seja mínimo. Estudamos o problema e modelo matemático considerado em Armentano et al. (2011). Para tratar o PIPD propomos heurísticas baseadas em programação matemática e geramos instâncias com múltiplos itens para testar o desempenho destas heurísticas. Comparamos os resultados obtidos pelas heurísticas com o solver comercial Cplex. Os resultados mostram que algumas das abordagens propostas obtiveram soluções de boa qualidade considerando as instâncias geradas. / In this work, the integrated production and vehicle routing problem (IPVRP) was studied. IPRP is solved by deciding on a integrated way the production, inventory control, distribution and vehicle routing decisions. In this type of problem, in each period, a single or multiple items are produced and distributed to costumers in order to meet a certain demand while minimizing the total cost, i.e., decide when and how much to produce of each item and the routes and distribution for each vehicle such that the final cost, which includes production, inventory and distribution costs is minimal. We considered the problem and mathematical model studied in Armentano et al. (2011). In order to deal with IPRP, heuristics based on mathematical programming were proposed together with multiple items instances to test the performance of those heuristics. We compare their results with the comercial solver Cplex. Results showed that some proposed heuristics obtained good quality solutions considering the generated instances.
16

Integrated Production and Distribution Planning for a Food Processing Company

Madhvarayan, Vishnu 24 May 2016 (has links)
No description available.
17

A production and inventory control system design for the fenton art glass company

Archibald, George January 1983 (has links)
No description available.
18

Computer-aided design of integrated production planning and inventory control systems

Handal, Dawud Kamal January 1987 (has links)
No description available.
19

Modeling, Analysis, and Algorithms for Some Supply Chain Logistics Optimization Problems

Sun, Fangzhou 18 June 2019 (has links)
In today's competitive market place, all the components of a supply chain must be well coordinated to achieve economic and service goals. This dissertation is devoted to the modeling, analysis, and development of solution approaches for some logistics problems with emphasis on coordination of various supply chain components and decisions. Specifically, we have addressed four problems in this domain that span various decision levels. The first problem deals with integrated production and shipping scheduling for a single manufacturer and multiple customers. We develop an optimum-seeking algorithm and a fast heuristic, both of which exploit structural properties of the problem. The second problem is a joint production and delivery scheduling problem in which a single vendor supplies goods to a single buyer over a finite horizon. We model this multi-period problem by using a dynamic programming framework and develop an effective Lagrange multiplier method for the solution of the single-period problem, which is then used to solve the multi-period problem. We show that the optimal shipments in each period follow a pattern of geometric-then-equal sizes except for the last shipment, which may be of a larger size. We also show that an optimal solution for the infinite horizon problem can be derived as a special case of our finite horizon approach. In addition, we propose two fast heuristic methods, which, as we show, can obtain almost optimal solutions. We also address the design and logistics operation of biomass feedstock supply chain. To that end, we consider two problems. The first of these problems arises in the context of delivering biomass sorghum to a biorefinery. We propose multi-period, mixed integer linear programming models, which prescribe the strategic and tactical logistics decisions. Our aim is to investigate different logistical configurations available in a sorghum biomass feedstock logistics system. The second of these problems further allows sharing of loadout equipment among storage facilities. We develop an efficient Benders decomposition-based algorithm, and also, two heuristic methods that are capable of effectively solving large-scale instances. We also show the advantage of using mobile equipment. / Doctor of Philosophy / Invariably, logistics cost constitutes a significant portion of the total cost incurred in operating a supply chain. In today’s fierce market competition, it is imperative to reduce this cost to a maximum extent. To that end, our work in this dissertation is devoted to the modeling, analysis, and development of solution approaches for some supply chain problems with the aim of reducing logistics cost. Specifically, we address four problems that span strategic-, tactical- and operational-level decisions in supply chain optimization. The first problem that we address deals with integrated production and shipping scheduling for a single manufacturer and multiple customers. Our aim is to integrate the production and shipping functions of a manufacturer for the objective of minimizing the sum of the shipping cost and the penalty incurred for late deliveries. We develop an optimum-seeking algorithm and a fast heuristic both of which exploit structural properties of the problem. The results of our computational investigation reveal efficacy of our approaches and a significant benefit that accrues from integrating the production and distribution functions. In the second problem, we address a joint production and delivery scheduling problem in which a single vendor supplies goods to a single buyer over a finite horizon. The vendor’s production rate and buyer’s demand rate can vary from period to period and are known in advance. The objective is to determine a production/shipment schedule that minimizes the total cost of production setup, shipment of orders, and holding of inventory at both the vendor and the buyer. We model this problem as a dynamic program, each stage of which constitutes a single-period problem with prescribed starting and ending inventory levels. We develop an effective approach for the solution of this single-period problem, which is then embedded within the dynamic programming framework. We show that the optimal shipments in each period follow a pattern of geometric-then-equal sizes except for the last shipment, which may be larger in size. We show that an optimal solution for the infinite horizon problem can be obtained as a special case of our finite horizon approach. In addition, we propose two fast heuristic methods, which, as we show, can obtain almost optimal solutions. For the third problem, we aim to address the design and operation of a biomass feedstock supply chain. We first present a comprehensive taxonomic literature review of the work in this area that exploits the operations research (OR) methodologies. Then, we study sorghum-biomass-to-biofuel logistics supply chain, and call it as a sorghum biomass feedstock logistics system (S-BFLS). We propose a multi-period, mixed integer linear programming model which prescribes the strategic locations and sizes of storage facilities, number of equipments to purchase, and allocation of farms to satellite storage facilities (SSLs), as well as tactical decisions including period-to-period biomass transportation flows and period-to-period biomass inventory plans. We study a wide spectrum of available harvest, preprocessing, transportation, and storage options as a part of the sorghum biomass feedstock logistics system. We have also investigated the option of just-in-time (JIT) delivery in conjunction with regular delivery, and call it as a hybrid delivery system. Our model is applied to a real-life-inspired case. Based on our analysis, the most cost-effective S-BFLS consists of forage-chopping for harvesting, bunkers or bags for ensiling, and hybrid delivery. Ensiling by modules is not found to be as cost-effective as by bags or bunkers due to the occurrence of high equipment ownership cost and operating cost. Compression of biomass is also not found to be cost-effective. It incurs extra equipment ownership and operating costs while not amounting to sufficient reduction in transportation cost because of the requirement of over 50% moisture content for ensiling. Forage-chop harvest and whole-stalk harvest have little difference in economic effectiveness. The hybrid delivery system is found to be effective since it reduces logistics cost for all the configurations. In the fourth and last problem, we permit sharing of mobile equipment among SSLs for loading biomass on tractor-trailers. We develop an efficient Benders decomposition algorithm (BA) to solve this problem. Our model formulation implicitly takes into account transportation of loadout equipment among SSLs. The BA further takes advantage of this feature of our formulation and Benders cuts. We have also proposed two fast approximate methods called Heuristics H1 and H2, both of which exploit the decision hierarchy of the problem. Computational experiments reveal efficacy of the proposed methods. Heuristic H2 generates fast and high quality solutions. However, the BA generates solution of desired accuracy (optimality gap) when not optimal. Our real-life-inspired case study has shown that 1.73–4.13% of cost reduction can be achieved by mobilizing loadout equipment in a BFSC. Also, expensive equipment leads to a greater benefit due to mobilization.
20

Din?mica da mat?ria org?nica, fertilidade e agrega??o do solo em ?reas sob diferentes sistemas de uso no Cerrado goiano. / Organic matter dynamic, soil fertility and aggregation in areas under different agricultural systems in Cerrado, Goi?s State.

Loss, Arc?ngelo 10 June 2011 (has links)
Submitted by Leticia Schettini (leticia@ufrrj.br) on 2016-10-04T15:54:19Z No. of bitstreams: 1 2011 - Arcangelo Loss.pdf: 3517882 bytes, checksum: 70d6fb3cef54e289b9abe89818c070c1 (MD5) / Made available in DSpace on 2016-10-04T15:54:19Z (GMT). No. of bitstreams: 1 2011 - Arcangelo Loss.pdf: 3517882 bytes, checksum: 70d6fb3cef54e289b9abe89818c070c1 (MD5) Previous issue date: 2011-06-10 / Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ, FAPERJ, Brasil / The Integrated Agriculture and Cattle-raising System (IACRS) is an excellent option for Cerrado soils, since the association with grasses (Brachiaria) intensify biomass production, especially in the year dry season. The No-till System (NTS) interspersed with brachiaria (Urochloa ruziziensis) and in consortium with maize (IACRS), when compared to the IACRS without brachiaria provides the best balance between distribution of C in the more labile and recalcitrant fractions of soil organic matter (SOM), and increases C and N stock, and soil aggregation. The general objective of this study was to evaluate the contribution of IACRS system on soil fertility, in chemical and physical fractions of SOM, in the distribution of oxidized carbon fractions, in soil aggregation, and C and N stocks in different land use systems in Cerrado, Goias State. Two areas with crop rotation were evaluated in Montividiu municipality, Goias State, identified as: IARCS (Brachiaria + corn/bean/cotton/soybean) and NTS (sunflower/millet/soy/corn). A natural area of Cerrado was taken as natural soil reference. Soil was sampled at 0.0-5.0; 5.0-10.0; 10.0-20.0 and 20.0-40.0 depths, and also up to 100.0 cm, in a randomized design. In Chapter I it was evaluated bulk density (BD), mineralogy properties, and soil fertility. Due to the animal range used in the IACRS, it was not observed increase in BD in comparison to the area without cattle (NTS). The values of SiO2/Al2O3 (ki) soil ratio indicate dominance of gibbsite in the Cerrado natural area, and kaolinite in the cultivated areas. The IACRS, associated with crop and pasture fertilization, resulted in higher soil fertility and nutrient stocks, compared with the NTS. In Chapter II physical and chemical indicators of SOM were evaluated. The total organic carbon (TOC), stocks of C in the humic acid fraction (C-HAF) and oxidizable carbon, and the physical indicators, particulate organic carbon (POC), light organic matter (LOM) and free light fraction (FLF), allowed inferring that IACRS increased these SOM fractions when compared with the NTS. The IACRS also provided a balanced distribution of C labile forms (F1) and recalcitrant (F4) in the soil, a higher degree of SOM humification, and better stratification of POC than the NTS area. In chapter III it was evaluated the soil aggregation, distribution of C and N, natural abundance of 13C and 15N in aggregates and C-CO2 (mineralization carbon) from soil aggregates incubation. IACRS increased: soil aggregation indexes (0-5 and 5-10 cm), TOC and N (0-5 cm), formation of water stable aggregates (5-10 cm), and also had higher accumulation of C-CO2 than NTS. In Chapter IV the distribution of TOC, N total, natural abundance of 13C and 15N were assessed, and quantified the TOC and nitrogen values. The usage of Urochloa ruziziensis associated with IACRS, increased the TOC levels (0-30 cm) and N (0-20 cm), when compared with NTS. It was possible to conclude that IACRS was more efficient to storage TOC than the natural Cerrado area in the 10.0-20.0 and 20.0-30.0 cm layers, and for the sum of the layers 0.0-40.0, and 0.0-60.0 cm. The use of legumes in the crop systems resulted in higher values of 15N compared to Cerrado area. The replacement of the original Cerrado vegetation by agriculture resulted in changes in 13C, as proven after 17 years of cultivation, by incorporation of carbon from grasses in areas of NTS and IACRS. / O sistema de Integra??o Lavoura-Pecu?ria (ILP) ? uma excelente op??o de uso para solos do Bioma Cerrado, pois a associa??o com esp?cies po?ceas (braqui?ria) intensifica a produ??o de palhada, principalmente no per?odo seco do ano. O Sistema Plantio Direto (SPD) intercalado com braqui?ria (Urochloa ruziziensis) e consorciado ao milho safrinha (ILP), comparado ao SPD sem braqui?ria, pode conduzir a equil?brio entre a distribui??o do C das fra??es da mat?ria org?nica do solo (MOS) mais l?beis e recalcitrantes e aumentar estoques de C e N e a agrega??o do solo. O objetivo geral do estudo foi avaliar contribui??es do sistema de ILP na fertilidade do solo, nas fra??es qu?micas e f?sicas da MOS, na distribui??o das fra??es de carbono oxid?vel, na agrega??o do solo e nos estoques de C e N em diferentes sistemas de uso do solo no Cerrado goiano. Foram avaliadas duas ?reas com rota??o de culturas em Montividiu, GO: ILP (milho+braqui?ria/feij?o/algod?o/soja) e SPD (girassol/milheto/soja/ milho). Uma ?rea de Cerrad?o natural foi tomada como condi??o original do solo. Foram coletadas amostras de terra nas profundidades de 0,0-5,0; 5,0-10,0; 10,0-20,0 e 20,0-40,0 cm, e, tamb?m at? 100 cm, em delineamento inteiramente casualizado. No Cap?tulo I foram avaliadas a densidade do solo (Ds), caracteriza??o mineral?gica e fertilidade do solo. Devido a lota??o animal utilizada no ILP n?o foram constatados aumentos da Ds em compara??o ? ?rea sem pisoteio animal (SPD). Os valores da rela??o SiO2/Al2O3 (ki) no solo indicam predom?nio de gibbsita na ?rea de Cerrad?o e de caulinita nas ?reas cultivadas. O sistema de ILP, mais ?s aduba??es das culturas e na braqui?ria, acarretou maior fertilidade do solo e estoques de nutrientes comparados ao SPD. No Cap?tulo II foram avaliados indicadores f?sicos e qu?micos da MOS. Os indicadores carbono org?nico total (COT), estoques de C da fra??o ?cido h?mico (C-FAH) e C oxid?vel e, os indicadores f?sicos, C org?nico particulado (COp), mat?ria org?nica leve (MOL) e fra??o leve livre (FLL), permitiram inferir que o sistema de ILP aumentou essas fra??es da MOS comparado ao SPD. No sistema de ILP a distribui??o das formas de carbono l?beis (F1) e recalcitrantes (F4) no solo foi mais equilibrada, com maior grau de humifica??o da MOS e melhor estratifica??o do COp, comparado ao SPD. No cap?tulo III foram avaliados os ?ndices de agrega??o do solo, a distribui??o dos teores de C e N e a abund?ncia natural de 13C e 15N dos agregados e o C-CO2 (carbono mineraliz?vel) proveniente da incuba??o de agregados do solo. A ILP aumentou os ?ndices de agrega??o do solo (0-5 e 5-10 cm), os teores de COT e N (0-5 cm), a forma??o de agregados est?veis em ?gua (5-10 cm) e tamb?m o ac?mulo de C-CO2, comparada ao SPD. No Capitulo IV foi avaliada a distribui??o do COT, N total, abund?ncia natural de 13C e 15N, e quantificados os estoques de COT e N do solo. A utiliza??o da Urochloa ruziziensis com rota??o de culturas (ILP) aumentou os teores de COT (0-30 cm) e N (0-20 cm), comparada ? rota??o de culturas (SPD). Conclui-se que o sistema de ILP foi mais eficiente em estocar COT no solo que a ?rea de Cerrad?o nas camadas de 10,0-20,0 e 20,0-30,0 cm e, na soma das camadas de 0,0-40,0 e 0,0-60,0 cm. O uso de leguminosas nas ?reas cultivadas acarretou em maiores valores de 15N em compara??o a de Cerrad?o. A substitui??o da vegeta??o original de Cerrad?o para implantar lavouras acarretou mudan?as do 13C, sendo comprovada, ap?s 17 anos de cultivo, a incorpora??o de C das po?ceas nas ?reas de SPD e ILP.

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