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Filtrato dinamika Jėrubaičių sąvartyne / Landfill leachate dynamic in JėrubaičiaiSimaitis, Donatas 16 June 2010 (has links)
Vienu iš pagrindiniu geologinės aplinkos teršėju yra laikomi sąvartynai. Todėl daugelyje šalių jie yra inventorizuojami ir tiriami, prognozuojamas jų poveikis gamtinei aplinkai. Lietuvai sąvartynų poveikio aplinkai problema taip pat labai aktuali. Todėl imtasi konkrečių priemonių informacijos apie sąvartynus kaupimui ir jų taršos mąsto įvertinimo. Tuo tikslu buvo atliekama ir iki šiol tebevykdoma sąvartynų inventorizacija. Kai kuriuose sąvartynuose buvo vykdomi įvairaus detalumo geologiniai-hidrogeologiniai tyrimai. Šiame darbe analizuojama Jerubaičių sąvartyno filtrato dinamika. Pateikiama sąvartyne susikaupusio filtrato judėjimo schema. Bei jo valymas atvirkštinės osmozės būdu. Tiriamas filtrato kiekio kitimas keičiantis meteorologinėm sąlygom, analizuojamas laikotarpis nuo 2008.05.15 iki 2008.12.31. Tiriamas laikotarpis, nuo gegužės 15 iki sausio 1, apima visus metų laikus bei atspindi tipines Lietuvos meteorologinės sąlygos. Darbe tiriama filtrato susidarymo priklausomybė sąvartyne nuo atvežamų šiukšlių kiekio ir meteorologinių sąlygų. Duomenys pateikiami grafiškai juos apdorojus, duomenų statistiniam apdorojimui panaudota programa STATISTICA. / Landfill is considered as one of the main geo-environmental polluters. Therefore, in most countries they are inventoried, analyzed and forecast their impact for the natural environment. Lithuania landfill’s environmental problem is also relevant. Consequently, there are taken appropriate actions about landfills and their accumulation of pollution assessment. This was done and it is still ongoing landfill inventory. In some landfills there were carried out a wide range of detail geological-hydrogeological researches. This document analyzes Jėrubaičiai landfill leachate dynamics. There is available landfill leachate accumulated movement scheme and its cleaning by reverse osmosis method. This analysis shows leachate flow dynamics in different meteorological conditions. Research period was from 2008.05.15 to 2008.12.31. Selected research period is covering all seasons and represents Lithuanian meteorological conditions. In this document explored formation of leachate dependency from incoming garbage amount and weather conditions. Research data are represented graphically; program STATISTICA was used for statistical data processing.
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Queimadas de cana-de-açúcar e condições climáticas: mapeamento e estudo das relações com a saúde da população na região de Araraquara - SP / Burning of sugarcane and weather conditions: mapping and study of the relationship with the health of the population in the region of Araraquara - SPFaccini, Luiz Gustavo 26 February 2013 (has links)
Introdução: A cana-de-açúcar é cultivada no Brasil desde o período colonial, e está se expandindo desde a década de 1970. A queima da cana-de-açúcar na pré-colheita ocorre para facilitar o trabalho de corte, reduzir o volume de resíduos, controlar pragas, evaporar e concentrar o açúcar na haste e eliminar animais perigosos do canavial. A queima da cana-de-açúcar e os efeitos à saúde humana é o objeto de diversas pesquisas recentes. Objetivos: Verificar a evolução das queimadas e da produção de cana-de-açúcar, e sua correlação com as leis vigentes na região de Araraquara, no período de 2003 a 2011. Estudar, por diferentes métodos, a relação entre fatores climáticos, variáveis socioeconômicas, queimadas de cana-de-açúcar e doenças respiratórias e cardiovasculares. Metodologia: Revisão bibliográfica. Composição de banco de dados geográficos com as variáveis em estudo. Análise da qualidade dos dados. Elaboração de mapas temáticos e gráficos das variáveis. Cálculo do índice de Moran global das variáveis de estudo. Estatística por varredura, aglomerados espaço-temporais de dados de focos de queimadas e internações. Modelagem e análise por atribuição de pesos. Elaboração de mapas temáticos de comparação e análise a partir dos aglomerados espaço-temporais. Descrição dos resultados. Resultados: A revisão bibliográfica, entre outras coisas, mostrou que em diferentes países estão ocorrendo avanços em relação às queimadas de cana-de-açúcar, inclusive no Brasil. A produção de cana-de-açúcar aumentou nos últimos anos, consequentemente aumentando a quantidade de queimadas em oposição ao previsto nas leis vigentes. A análise por pesos não foi satisfatória os resultados de vulnerabilidade obtidos não representaram bem as relações entre as variáveis estudadas. A elaboração dos aglomerados espaço-temporais foi satisfatória. Os aglomerados espaciais dos focos de queimadas mostraram as áreas com maior intensidade de queimadas ao longo dos anos. Os aglomerados temporais dos focos de queimadas mostraram que a maior quantidade de focos ocorreu durante o período de safra da cana. Com os aglomerados espaciais das internações foi possível observar as áreas mais sensíveis, principalmente para as doenças respiratórias. Os aglomerados temporais das doenças mostraram os períodos do ano que a população sofre mais com as doenças. Os mapas de comparação mostraram os fatores climáticos que podem influenciar nas internações por doenças associados às queimadas de cana-de-açúcar foram: alta amplitude térmica, baixas temperaturas, queda de temperatura e direção dos ventos. Conclusões: No período de 2003 a 2011 ocorreu aumento no número de focos de queimadas associado ao aumento da produção de cana-de-açúcar. A diminuição das queimadas objetivada pelas leis vigentes não ocorre. Os aglomerados espaço-temporais representam as áreas e os períodos dos anos que têm maior influência das queimadas de cana-de-açúcar, das variáveis socioeconômicas e do clima sobre as doenças na população. No geral as restrições para as queimadas de cana-de-açúcar estão melhorando, mas novas pesquisas e ações do poder público devem continuar existindo / Introduction: The sugarcane is grown in Brazil since colonial times, and is expanding since the 1970s. The burning of sugarcane in the pre-harvest occurs to facilitate the work of the cutting, reduce the volume of waste, pest control, evaporate and concentrate the sugar in the cane and eliminate dangerous animals of the plantation. The burning of sugarcane and the effects on human health is the subject of several recent studies. Aims: Check the evolution of fires and the production of sugarcane, and its correlation with the current laws in the region of Araraquaras city, Brazil, in the period from 2003 to 2011. Study by different methods, the relationship between climatic factors, socioeconomic variables, burning of sugarcane and respiratory and cardiovascular diseases. Methods: Literature review. Compose geographic database with the study variables. Data quality analysis. Preparation of thematic maps and graphs of the variables. Calculation of global Moran index of variables. Stats for scanning, space-time clusters of fires and admissions. Modeling and analysis by assigning weights. Preparation of thematic maps for comparison and analysis from the space-time clusters. Description of results. Results: The literature review, among other things, showed that advances are occurring in different countries over the burning of sugarcane, including Brazil. The production of sugarcane grown in recent years, thereby increasing the amount of fires in opposition to the planned laws. The analysis weights was unsatisfactory results obtained vulnerability did not represent well the relationships between variables. The development of space-time clusters was satisfactory. The spatial clusters of fires showed the areas with greatest intensity of fires over the years. The temporal clusters of fires showed that the largest number of fires occurred during the sugarcane harvest. With the clusters of hospitalizations was possible to observe the most sensitive areas, especially for respiratory diseases. The temporal clusters of disease showed periods of the year that people suffer more from diseases. The comparison maps showed the climatic factors that can influence admissions for diseases associated with the burning of sugarcane were high thermal amplitude, low temperature, temperature drop and wind direction. Conclusions: In the period 2003 to 2011 there was an increase in the number of fires associated with increased production of sugarcane. The decrease of burning objectified by laws does not occur. The space-temporal clusters represent areas and periods of the years that there are most influence of sugarcanes burning, socioeconomic variables and climate on diseases in the population. In general restrictions for the burning of sugarcane are improving, but further research and actions of the government should continue to exist
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Queimadas de cana-de-açúcar e condições climáticas: mapeamento e estudo das relações com a saúde da população na região de Araraquara - SP / Burning of sugarcane and weather conditions: mapping and study of the relationship with the health of the population in the region of Araraquara - SPLuiz Gustavo Faccini 26 February 2013 (has links)
Introdução: A cana-de-açúcar é cultivada no Brasil desde o período colonial, e está se expandindo desde a década de 1970. A queima da cana-de-açúcar na pré-colheita ocorre para facilitar o trabalho de corte, reduzir o volume de resíduos, controlar pragas, evaporar e concentrar o açúcar na haste e eliminar animais perigosos do canavial. A queima da cana-de-açúcar e os efeitos à saúde humana é o objeto de diversas pesquisas recentes. Objetivos: Verificar a evolução das queimadas e da produção de cana-de-açúcar, e sua correlação com as leis vigentes na região de Araraquara, no período de 2003 a 2011. Estudar, por diferentes métodos, a relação entre fatores climáticos, variáveis socioeconômicas, queimadas de cana-de-açúcar e doenças respiratórias e cardiovasculares. Metodologia: Revisão bibliográfica. Composição de banco de dados geográficos com as variáveis em estudo. Análise da qualidade dos dados. Elaboração de mapas temáticos e gráficos das variáveis. Cálculo do índice de Moran global das variáveis de estudo. Estatística por varredura, aglomerados espaço-temporais de dados de focos de queimadas e internações. Modelagem e análise por atribuição de pesos. Elaboração de mapas temáticos de comparação e análise a partir dos aglomerados espaço-temporais. Descrição dos resultados. Resultados: A revisão bibliográfica, entre outras coisas, mostrou que em diferentes países estão ocorrendo avanços em relação às queimadas de cana-de-açúcar, inclusive no Brasil. A produção de cana-de-açúcar aumentou nos últimos anos, consequentemente aumentando a quantidade de queimadas em oposição ao previsto nas leis vigentes. A análise por pesos não foi satisfatória os resultados de vulnerabilidade obtidos não representaram bem as relações entre as variáveis estudadas. A elaboração dos aglomerados espaço-temporais foi satisfatória. Os aglomerados espaciais dos focos de queimadas mostraram as áreas com maior intensidade de queimadas ao longo dos anos. Os aglomerados temporais dos focos de queimadas mostraram que a maior quantidade de focos ocorreu durante o período de safra da cana. Com os aglomerados espaciais das internações foi possível observar as áreas mais sensíveis, principalmente para as doenças respiratórias. Os aglomerados temporais das doenças mostraram os períodos do ano que a população sofre mais com as doenças. Os mapas de comparação mostraram os fatores climáticos que podem influenciar nas internações por doenças associados às queimadas de cana-de-açúcar foram: alta amplitude térmica, baixas temperaturas, queda de temperatura e direção dos ventos. Conclusões: No período de 2003 a 2011 ocorreu aumento no número de focos de queimadas associado ao aumento da produção de cana-de-açúcar. A diminuição das queimadas objetivada pelas leis vigentes não ocorre. Os aglomerados espaço-temporais representam as áreas e os períodos dos anos que têm maior influência das queimadas de cana-de-açúcar, das variáveis socioeconômicas e do clima sobre as doenças na população. No geral as restrições para as queimadas de cana-de-açúcar estão melhorando, mas novas pesquisas e ações do poder público devem continuar existindo / Introduction: The sugarcane is grown in Brazil since colonial times, and is expanding since the 1970s. The burning of sugarcane in the pre-harvest occurs to facilitate the work of the cutting, reduce the volume of waste, pest control, evaporate and concentrate the sugar in the cane and eliminate dangerous animals of the plantation. The burning of sugarcane and the effects on human health is the subject of several recent studies. Aims: Check the evolution of fires and the production of sugarcane, and its correlation with the current laws in the region of Araraquaras city, Brazil, in the period from 2003 to 2011. Study by different methods, the relationship between climatic factors, socioeconomic variables, burning of sugarcane and respiratory and cardiovascular diseases. Methods: Literature review. Compose geographic database with the study variables. Data quality analysis. Preparation of thematic maps and graphs of the variables. Calculation of global Moran index of variables. Stats for scanning, space-time clusters of fires and admissions. Modeling and analysis by assigning weights. Preparation of thematic maps for comparison and analysis from the space-time clusters. Description of results. Results: The literature review, among other things, showed that advances are occurring in different countries over the burning of sugarcane, including Brazil. The production of sugarcane grown in recent years, thereby increasing the amount of fires in opposition to the planned laws. The analysis weights was unsatisfactory results obtained vulnerability did not represent well the relationships between variables. The development of space-time clusters was satisfactory. The spatial clusters of fires showed the areas with greatest intensity of fires over the years. The temporal clusters of fires showed that the largest number of fires occurred during the sugarcane harvest. With the clusters of hospitalizations was possible to observe the most sensitive areas, especially for respiratory diseases. The temporal clusters of disease showed periods of the year that people suffer more from diseases. The comparison maps showed the climatic factors that can influence admissions for diseases associated with the burning of sugarcane were high thermal amplitude, low temperature, temperature drop and wind direction. Conclusions: In the period 2003 to 2011 there was an increase in the number of fires associated with increased production of sugarcane. The decrease of burning objectified by laws does not occur. The space-temporal clusters represent areas and periods of the years that there are most influence of sugarcanes burning, socioeconomic variables and climate on diseases in the population. In general restrictions for the burning of sugarcane are improving, but further research and actions of the government should continue to exist
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Perspectives on the vulnerability of the Swedish electricity distribution system : Extreme weather conditions and climate changePlejert, Tina January 2005 (has links)
<p>This study deals with the perspective of vulnerability of the Swedish electricity distribution system to climate and weather related risks. How and to what extent the electricity sector is adapting to the risk and what possibilities are formed in this respect are investigated. This is a quantitative and qualitative analysis where statistical data has been used to apprehend the extent of disturbances of the electricity distribution system and their causes. Interviews have been used in order to investigate different views among actors working within the electricity distribution system sector.</p><p>The result shows that the dominating cause of disturbances in the electrical network in Sweden is the weather, giving most hours of breaks. The countryside has more often disturbances than urban areas. It also emerges that it is the lines overhead that are most affected by disturbances. The system is flexible. If one line is disturbed the electricity can be distributed using another line (redundancy). It seems like there is a diversion between the respondents on how and if a future climate change really is a risk for the electricity distribution system. It is clear that the vulnerability has increased in the society during the past 10-20 years, and so has the societal costs of the disturbances because of the increasing dependence on electricity. Reducing the consequences of a weather related impact on the electrical system will make society more resilient and less vulnerable. The respondents in this study are somewhat adapting to the weather related risks that they have identified with technical solutions. It is important to learn more about how the electrical system properties influence the sensitivity in society. There is a need to investigate the dependency of electricity in society. It is also important that all the actors have the same interpretation of the difference between a recurrent event and a nature disaster. More work should be done to clarify where the responsibility for adapting the electrical sector to the possible climate change lies. This complex responsibility issue with all affected actors influences the sensitivity of society and the electrical system.</p>
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Perspectives on the vulnerability of the Swedish electricity distribution system : Extreme weather conditions and climate changePlejert, Tina January 2005 (has links)
This study deals with the perspective of vulnerability of the Swedish electricity distribution system to climate and weather related risks. How and to what extent the electricity sector is adapting to the risk and what possibilities are formed in this respect are investigated. This is a quantitative and qualitative analysis where statistical data has been used to apprehend the extent of disturbances of the electricity distribution system and their causes. Interviews have been used in order to investigate different views among actors working within the electricity distribution system sector. The result shows that the dominating cause of disturbances in the electrical network in Sweden is the weather, giving most hours of breaks. The countryside has more often disturbances than urban areas. It also emerges that it is the lines overhead that are most affected by disturbances. The system is flexible. If one line is disturbed the electricity can be distributed using another line (redundancy). It seems like there is a diversion between the respondents on how and if a future climate change really is a risk for the electricity distribution system. It is clear that the vulnerability has increased in the society during the past 10-20 years, and so has the societal costs of the disturbances because of the increasing dependence on electricity. Reducing the consequences of a weather related impact on the electrical system will make society more resilient and less vulnerable. The respondents in this study are somewhat adapting to the weather related risks that they have identified with technical solutions. It is important to learn more about how the electrical system properties influence the sensitivity in society. There is a need to investigate the dependency of electricity in society. It is also important that all the actors have the same interpretation of the difference between a recurrent event and a nature disaster. More work should be done to clarify where the responsibility for adapting the electrical sector to the possible climate change lies. This complex responsibility issue with all affected actors influences the sensitivity of society and the electrical system.
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A probabilistic impact-focussed early warning system for flash floods in support of disaster management in South AfricaPoolman, Eugene Rene January 2015 (has links)
The development of the Severe Weather Impact Forecasting System (SWIFS) for flash flood
hazards in South Africa is described in this thesis. Impact forecasting addresses the need to
move from forecasting weather conditions to forecasting the consequential impact of these
conditions on people and their livelihoods. SWIFS aims to guide disaster managers to take early
action to minimise the adverse effects of flash floods focussing on hotspots where the largest
impact is expected. The first component of SWIFS produced an 18-hour probabilistic outlook of
potential occurrence of flash floods. This required the development of an ensemble forecast
system of rainfall for small river basins (the forecasting model component), based on the
rainfall forecast of a deterministic numerical weather prediction model, to provide an 18-hour
lead-time, taking into account forecast uncertainty. The second component of SWIFS covered
the event specific societal and structural impacts of these potential flash floods, based on the
interaction of the potential occurrence of flash floods with the generalised vulnerability to flash
floods of the affected region (the impact model component). The impact model required an
investigation into the concepts of regional vulnerability to flash floods, and the development of
relevant descriptive and mathematical definitions in the context of impact forecasting. The
definition developed in the study links impact forecasting to the likelihood and magnitude of
adverse impacts to communities under threat, based on their vulnerability and due to an
imminent severe weather hazard. Case studies provided evidence that the concept of SWIFS
can produce useful information to disaster managers to identify areas most likely to be
adversely affected in advance of a hazardous event and to decide on appropriate distribution of
their resources between the various hotspots where the largest impacts would be. SWIFS
contributes to the current international research on short-term impact forecasting by focussing
on forecasting the impacts of flash floods in a developing country with its limited spatial
vulnerability information. It provides user-oriented information in support of disaster manager
decision-making through additional lead-time of the potential of flash floods, and the likely
impact of the flooding. The study provides a firm basis for future enhancement of SWIFS to
other severe weather hazards in South Africa. / Thesis (PhD)--University of Pretoria, 2015. / gm2015 / Geography, Geoinformatics and Meteorology / PhD / Unrestricted
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Visual arctic navigation: techniques for autonomous agents in glacial environmentsWilliams, Stephen Vincent 15 June 2011 (has links)
Arctic regions are thought to be more sensitive to climate change fluctuations, making weather data from these regions more valuable for climate modeling. Scientists have expressed an interest in deploying a robotic sensor network in these areas, minimizing the exposure of human researchers to the harsh environment, while allowing dense, targeted data collection to commence. For any such robotic system to be successful, a certain set of base navigational functionality must be developed. Further, these navigational algorithms must rely on the types of low-cost sensors that would be viable for use in a multi-agent system. A set of vision-based processing techniques have been proposed, which augment current robotic technologies for use in glacial terrains. Specifically, algorithms for estimating terrain traversability, robot localization, and terrain reconstruction have been developed which use data collected exclusively from a single camera and other low-cost robotic sensors. For traversability assessment, a custom algorithm was developed that uses local scale surface texture to estimate the terrain slope. Additionally, a horizon line estimation system has been proposed that is capable of coping with low-contrast, ambiguous horizons. For localization, a monocular simultaneous localization and mapping (SLAM) filter has been fused with consumer-grade GPS measurements to produce full robot pose estimates that do not drift over long traverses. Finally, a terrain reconstruction methodology has been proposed that uses a Gaussian process framework to incorporate sparse SLAM landmarks with dense slope estimates to produce a single, consistent terrain model. These algorithms have been tested within a custom glacial terrain computer simulation and against multiple data sets acquired during glacial field trials. The results of these tests indicate that vision is a viable sensing modality for autonomous glacial robotics, despite the obvious challenges presented by low-contrast glacial scenery. The findings of this work are discussed within the context of the larger arctic sensor network project, and a direction for future work is recommended.
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Devine qui vient dîner … : graines des villes et graines des champs, ou l'impact de l'agriculture péri-urbaine sur les oiseaux des jardins / Guess who comes to dinner ... : seeds of towns and seeds of fields, or the impact of suburban agriculture on garden birdsPierret, Pauline 11 January 2018 (has links)
Nourrir les oiseaux dans les jardins privés est une activité très répandue en Occident. Elle fournit une remarquable opportunité de recherche et de suivi des populations d’oiseaux en hiver sur de larges échelles spatio-temporelles, en impliquant les citoyens dans des programmes de science participative. Nous avons utilisé le programme Oiseaux des Jardins, un programme de science participative coordonné par la Ligue de Protection des Oiseaux, pour étudier sur une grande échelle spatiale les variations d’abondance d’oiseaux en hiver dans les jardins qui fournissent de la nourriture. Le but de cette thèse est de comprendre quels paramètres peuvent expliquer les visites des oiseaux dans les jardins en hiver, saison traditionnellement considérée comme la plus décisive pour leur survie. Nous montrons que les jardins distribuant de la nourriture, proches de milieux agricoles intensifs, attirent les oiseaux en réponse à une raréfaction des ressources alimentaires naturelles, causée par l’intensité des pratiques agricoles. Cette relation est encore plus forte pour les espèces spécialistes des milieux agricoles. Les variations d’abondance d’oiseaux dans les jardins fluctuent selon les années et les conditions météorologiques, sans présenter de pattern de réponse commun entre espèces, en raison de leur biologie et écologie différentes. Ce suivi des oiseaux en hiver reflète également la tendance négative de population de plusieurs granivores, connue en France ou en Europe en période de reproduction, confirmant que l’utilisation des jardins avec mangeoires est un bon moyen de suivre les tendances des populations d’oiseaux. Nous suspectons que les variations d’abondances à l’échelle spatiale peuvent également refléter l’effet d’activités humaines, telles que le braconnage des passereaux, mais un travail supplémentaire est nécessaire pour confirmer cette hypothèse. Les résultats de cette thèse peuvent également aider au maintien des espèces granivores en déclin, en apportant des conseils adaptés à la distribution de nourriture de substitution pour les oiseaux dans les paysages agricoles intensifs, tout en continuant à engager le public dans le suivi et la protection de la nature. / Supplementary feeding of wild birds in private backyards is a globally widespread pastime. It provides a wonderful opportunity for research and survey of winter bird populations at spatial and temporal large-scales by involving householders in citizen science programs. We used data from the French national garden birdwatch scheme, a citizen science program operated by the Ligue de Protection des Oiseaux, to study winter bird abundance variations in gardens which provided food supply, at a large spatial scale. This thesis aims to understand which factors influence the visit of gardens by birds during winter, a season traditionally pointed out to have the greatest impact on passerine survival. We highlighted that gardens with feeders located close to intensively cultivated farmland attract birds as a response of the countryside natural resource scarcity leads by intensive agricultural practices. This relationship being stronger for farmland seedeater species. Variations in the use of garden by birds also fluctuate between years and with weather conditions, but the variations were not similar among species. This being consistent with the expected influence of their ecological and biological differences. This garden bird survey in winter also reflected the global negative trends observed for some granivorous species in France or Europe during the breeding season, confirming that the use of garden bird feeders by wild bird species offers a new tool to survey the global population trends. We also suspect that variation in abundance could mirror spatial differences, and maybe mirror human activities impacts such as poaching, but this part requires further investigation. Finally, our work could be beneficial for maintaining declining seedeater species, by advising to supply birds with winter food in garden located in intensive agricultural landscape, while continuing to engage the public with nature.
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Época de semeadura e local de produção na germinação de sementes do algodoeiro / Sowing epoch and place of cultivation in the germination of cottonseedsPereira, Marcelo Oliveira 31 October 2012 (has links)
The place where cotton-plant is cultivated to produce seeds and its sowing time are extremely important, especially due to local climatic conditions. Based on this premise, this work aimed at verifying the influence distinct epochs of sowing in two different places had on the germination of cottonseed genotypes in the season 2007/2008. This study was carried out in two municipalities: Itumbiara, Goiás state, and Uberlândia, Minas Gerais state. Sowing of DeltaOpal, NuOpal, DP90B, DP604B, and Delta Penta genotypes seeds took place in the first half of November and in this first and second half of December. The experimental design was completely randomized in split plot with six replications. Evaluation included genotypes in the plots and sowing epochs in the subplots. After being manually harvested, cottonseeds were processed, delinted with sulfuric acid and then subjected to germination test to verify normal and abnormal (deformed, damaged and deteriorated) seedlings as well as dead seeds. Results statistical analysis allow concluding that in Itumbiara the first and second half of December are the best sowing time to produce cottonseeds from genotypes NuOpal, DP604G, and DP90B; while in Uberlândia the best sowing time were the second half of November and first half of December, no matter the genotype used. / O local de produção de sementes do algodoeiro e a época de semeadura da cultura são extremamente importantes, sobretudo por causa das condições climáticas regionais. Tendo em vista essa premissa, este trabalho objetivou avaliar a influência que épocas distintas de semeadura em dois locais de produção teve na germinação de sementes de genótipos de algodoeiro no ano agrícola 2007/2008. O trabalho foi realizado em Itumbiara, GO, e Uberlândia, MG. As semeaduras ocorreram na segunda quinzena de novembro e na primeira e segunda quinzenas de dezembro. Foram usadas sementes de algodão dos genótipos: DeltaOpal, NuOpal, DP90B, DP604B e DeltaPenta. O delineamento experimental foi inteiramente casual, em parcelas subdivididas com seis repetições. A avaliação nas parcelas incluiu os genótipos; nas subparcelas, as épocas de semeadura. Após a colheita manual, o algodão em caroço foi beneficiado e as sementes foram deslintadas com ácido sulfúrico, para depois ser submetidas ao teste de germinação a fim de avaliar plântulas normais, plântulas anormais (deformadas, danificadas e deterioradas) e sementes mortas. A análise estatística dos resultados obtidos permitiu concluir que, em Itumbiara, as duas quinzenas de dezembro são épocas mais adequadas para semear o algodoeiro a fim de produzir semente (para os genótipos NuOPAL, DP90B e DP604G); e que, em Uberlândia, as melhores épocas são a segunda quinzena de novembro e a primeira de dezembro (independentemente do genótipo usado). / Mestre em Agronomia
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Liberação de nitrogênio em diferentes solos e épocas de cultivo sob adubação orgânica / Nitrogen release in different soils and growing seasons under organic fertilizationFioreze, Claudio 30 April 2010 (has links)
Organic fertilizers promote improvements in soil properties and are important in providing balanced nutrients to plants. The officials parameters adopted by the Commission of Chemistry and Soil Physics in the States of Rio Grande do Sul Santa Catarina to calculate the amount of organic fertilizer are its mean composition and the efficiency index of nutrient release (EINR) to fulfill the demand of each system crops. This indicator is related mainly to the type of organic residual, but the other factors affecting the mineralization are not adequately addressed, such as climatic conditions and soil texture, among others. The expectation of this work is that these factors are especially relevant in regions with large variation of soil types and climatic conditions, such as the South of Brazil region. So, the factors cropping season and soil texture were studied under the application of two different organic sources (pig slurry and chicken litter) in the field and in laboratory experiments. The texture effect was analyzed in an incubation of three soils containing 238, 470 and 605 mg clay kg soil-1, which was evaluated during 112 days of evolution of mineral nitrogen (N-NH4+ + N-NO3-), the net mineralization and % mineralization of total N and organic added. The influence of growing season was tested under field conditions in two crop series starting with the potato (summer and winter), which evaluated the productivity and nutrient cycling in three crops per system. The results of incubation showed that soil type affects the N dynamics in the soil after the addition of organic fertilizers. Most clayey soils make slowly immobilization and nitrification of ammonium, independently of addition of the broiler litter or pig slurry, which reduces the N pollution potential. The net N mineralization was greater in sandy soil due to lower physical-chemical protection of colloids. Also were greater with the chickens litter due to the amount of total N added have been much higher compared to pig slurry. The results of N available to plants (%NAP) and net mineralization of nitrogen in the soil (%Nminnet) with the addition of organic fertilizers indicate that EINR is overestimated in relation to N effectively added to the soils, and can result in depletion of soil organic matter in the long term growing. Also concludes that, to sandy soils or when manure are rich in available N, that must be done a N fractionated application between plantation and cover fertilization. In field experiments, there would significant differences in the efficiency of release of N in cropping systems of "summer" and "winter". The immediate effect was equal in the summer period to all fertilization sources, but in the winter the mineral source was 10-20% more efficient, showing the effect of temperature and soil moisture in the availability of N in soils under organic fertilization. The residual effect of chickens litter in the second crops was lower than expected in comparison to the pig slurry and mineral fertilizer, since the efficiency index of N liberation would be 20% for chickens litter and zero for the slurry. However only in the third crop that litter exceeded the slurry in dry matter production of summer crop (maize) and winter (black oat). Finally, due very different climatic conditions in South of Brazil, the results indicate that it necessary more and integrated studies about the impact of crop date and soil type to refine the parameters of the recommendation of organic fertilizer, making it thus more sustainable. / Os adubos orgânicos promovem melhorias nas propriedades do solo e são importantes no fornecimento equilibrado de nutrientes às plantas. Os parâmetros oficiais adotados pela Comissão de Química e Física do Solo dos Estados do Rio Grande do Sul Santa Catarina para calcular a quantidade de adubo orgânico, são a sua composição média e o índice de eficiência de liberação dos nutrientes (IELN) frente à demanda de cada sistema de cultivos. Este último indicador está associado essencialmente ao tipo de resíduo, porém os demais fatores que afetam a mineralização não são devidamente considerados, como as condições climáticas e a textura do solo, entre outros. A expectativa do presente trabalho é de que esses fatores sejam especialmente relevantes em regiões de grande variação edafoclimática, como o Sul do Brasil. Assim, os fatores época de plantio e textura do solo foram estudados sob a aplicação de duas fontes orgânicas distintas (dejeto líquido suíno e cama de aves de corte), a campo e em laboratório. O efeito da textura foi discutido numa incubação de três solos contendo 238, 470 e 605 mg argila kg de solo-1, onde se determinou a evolução do N mineral (N-NH4+ + N-NO3-) durante 112 dias e se calculou a mineralização líquida e a % de mineralização do N total e orgânico adicionados. Já o efeito da época de cultivo foi testado a campo em duas sucessões iniciadas com cultura da batata (denominados de cultivos de verão e de inverno), onde se avaliou a produtividade e a ciclagem de nutrientes de três culturas por sistema. Os resultados da incubação mostraram que o tipo de solo afeta a dinâmica do N no solo após a adição de adubos orgânicos. Solos mais argilosos retardam a imobilização e a nitrificação do amônio, independente de se utilizar cama de aves de corte ou dejeto líquido de suínos, contribuindo para diminuir o potencial poluente do N. A mineralização líquida do N foi maior no solo arenoso devido à menor proteção físico-química da sua fração coloidal. Também foi maior com o uso da cama de aves de corte, em todos os solos, em função quantidade de N total adicionado ter sido bem maior em relação ao dejeto de suínos. Os resultados de N disponível às plantas (%NDP) e de mineralização líquida do N no solo (%NminL), com a adição dos adubos orgânicos, sinalizam que o IELN está superestimado em relação ao N que é efetivamente adicionado aos solos, podendo levar à depleção da matéria orgânica do solo a longo prazo. Também se infere que, para solos mais arenosos ou quando se dispõe de dejetos ricos em N disponível, faça-se a aplicação fracionada do N entre o plantio e em cobertura. Nos experimentos de campo, por sua vez, houve diferenças significativas na eficiência de liberação do N nos sistemas de cultivo de verão e de inverno . O efeito imediato foi igual no verão para as fontes cama de aves, dejeto suíno e adubo mineral, mas no cultivo de inverno a fonte mineral foi entre 10 a 20% mais eficiente, demonstrando o efeito da temperatura e da umidade na disponibilização de N nos solos sob adubação orgânica. O efeito residual da cama de aves no segundo cultivo foi inferior ao esperado na comparação com o dejeto suíno e adubo mineral, visto que o índice de eficiência de N seria de 20% para a cama e zero para o dejeto. Porém, foi só no terceiro cultivo que a cama superou o dejeto na produção de matéria seca no cultivo de verão (milho) e de inverno (aveia preta). Por fim, dada a grande diversidade edafoclimática no Sul do Brasil, os resultados apontam que se devem fazer mais estudos e de forma integrada sobre o impacto da época de plantio e tipo de solo para aperfeiçoar os parâmetros de recomendação da adubação orgânica, tornando-a assim mais sustentável.
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