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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.
151

Compostos nitrogenados e de carboidratos em pastos de capim-elefante (Pennisetum purpureum) cv. Cameroon manejados com intervalos de desfolhação fixo e variáveis / Nitrogen and carbohydrate fractions in elephant grass pastures (Pennisetum purpureum cv. Cameroon), managed with fixed and variable defoliation intervals

Romero, Jakeline Vieira 29 September 2008 (has links)
O presente estudo teve como objetivo a caracterização das frações protéicas e de carboidratos em pastagem de capim-elefante (Pennisetum purpureum cv. Cameroon), manejada com altas taxas de lotação no período das águas. O experimento foi realizado nas instalações do Departamento de Zootecnia da Esalq/USP. A forragem foi coletada nas estações do outono/2006, primavera/2006 e verão/2006-07, adotando-se intervalos de desfolhação fixos de 27 dias e variáveis, onde a entrada dos animais ocorreu quando o capim atingiu 1,05 m de altura (95 % IL). Foi determinada a composição bromatológica, frações protéicas e de carboidratos tanto por métodos químicos quanto pelo método de degradação in situ da forragem. A pastagem também foi avaliada quanto à massa de forragem (kg de MS por ha-1), composição morfológica e alturas do dossel na entrada e saída dos animais. Para as determinações no pasto utilizou-se o delineamento inteiramente aleatorizado com medidas repetidas no tempo. Para as frações protéicas A, B e C, foi realizado ensaio de degradabilidade in situ utilizando-se 4 garrotes castrados e canulados no rúmen. As amostras de forragem secas e moídas a 5 mm foram acondicionadas em sacos de nylon e incubadas no rúmen por 0, 3, 6, 12, 24, 48, 60, 72, 96 e 120 horas. O delineamento experimental foi em quadrados latinos 2x2 replicados. A duração do intervalo entre desfolhas não diferiu entre os tratamentos (P>0,05), em nenhuma das estações avaliadas. As alturas do dossel no pré-pastejo foram maiores (P<0,05) nos tratamentos com ID variável. Para altura do dossel em pós-pastejo, houve efeito somente da estação (P<0,05), com menores alturas na primavera (0,43 e 0,51 m), e maiores no verão (0,56 e 0,57 m) para os tratamentos com ID fixo e variável. Não foi verificada diferença (P>0,05) para produção de forragem entre os tratamentos. Apenas os teores de PB da forragem foram afetados pelos tratamentos (P<0,05), com menores valores para ID variável. Os teores de MS, FDN, FDA, lignina e PIDA não diferiram (P>0,05) entre os tratamentos. Somente a fração protéica B2 foi afetada, com maiores valores para ID variável (P<0,05). As frações A e B3 diferiram nas estações do ano (P<0,05), com o outono apresentando menores valores de A e maiores da B3. Não houve diferença para as frações B1 e C (P>0,05). No verão, a fração A+B1 dos carboidratos apresentou os menores valores dentre as estações (13,80 e 16,22 % para ID fixo e variável), e a fração B2, os maiores valores (76,59 e 73,42 %) (P<0,05). Não houve diferenças (P>0,05) para as variáveis de degradabilidade da MS e MO. Na degradabilidade da FDN, diferenças significativas foram observadas apenas para variável de DP e DE com taxa de passagem de 2 %/h no tratamento com ID fixo. A correção da contaminação microbiana resultou em aumento nos valores da fração protéica A e redução na B. Não houve efeito (P>0,05) para as variáveis da PB corrigida pela contaminação, exceto para a fração B, onde os valores foram maiores no outono (73,3 e 73,69%) e menores na primavera com ID variáveis (55,87%). / The present study designed to characerize the protein and carbohydrate fractions of elephant grass pasture (Pennisetum purpureum) cv. Cameroon, intensively grazed at high stocking rate during the rainy season. The experiment was carried in the Animal Sciences Department of the University of São Paulo (USP/ESALQ). Forage samples were collected during autumn and spring/2006 and summer/2006-07. Two defoliation intervals (DI) were adopted, fixed and variable. For the fixed DI treatment experimental animals had access to the paddocks every 27 days, and for the variable DI treatment experimental animals had access to the paddocks when the sward reached 1,05m height, corresponding to 95% light interception. Forage samples were analyzed for chemical composition and protein and carbohydrate fractions by chemical methods and with \"in situ\" degradation technique. Pasture was also analyzed for pre-grazing forage mass (kg DM ha-1) , morphologic composition, pre and post grazing sward heights. A completely randomized design with repeated measures was used for pasture determinations. For protein fractions (A, B, C) determinations, an in situ trial was developed using four rumen canulated steers. 5mm ground forage samples were conditioned in nylon bags and incubated in the rumen for 0, 3, 6, 12, 24, 48, 60, 72, 96 and 120 hours. The experimental design was a replicated 2x2 Latin square. The defoliation interval length did not differ (P>0,05) among treatments, in any season. Pre-grazing sward heights were higher (P<0,05) for the variable DI treatment. A season effect (P<0,05) was observed for post-grazing heights, with lower values observed on spring (0,43 and 0,51m) and higher on summer (0,56 and 0,57m) for both treatments. No differences (P>0,05) were observed among treatments for total forage mass. Only forage CP content was affected by treatments, with lower values (P<0,05) for variable DI. DM, NDF, ADF, lignin and ADIN were not different (P>0,05) among treatments. Protein B2 fraction was affected, showing higher values (P<0,05) for variable DI treatment. Fractions A and B3 were different among seasons, with lower fraction A and higher fraction B3 values during autumn (P<0,05). No differences were observed for fractions B1 and C (P>0,05). During summer carbohydrate fractions A + B1 showed the lowest values among seasons (13,80 and 16,22% for fixed and variable DI), and B2 fraction showed the highest values (76,59 and 73,42 %) (P<0,05). No differences were observed for DM and OM degradabilities variables (P>0,05). For NDF degradability significant differences were observed only PD and ED variables with 2%/h passage rate for fixed DI treatment. Microbial contamination adjustment resulted in higher protein A and lower protein B fraction values. No effects were observed (P>0,05) for microbial contamination adjusted CP variables, except for B fraction that showed higher values during autumn (73,3 and 73,69%) and lower during spring with variable DI (55,87%).
152

Morfogênese, acúmulo de forragem e teores de nutrientes de Panicum maximum cv. Tanzânia submetido a diferentes severidades de desfolhação e fertilidades contrastantes / Morphogenesis, forage net accumulation and nutritional status of Panicum maximum cv Tanzânia under contrasting fertilization rates and grazing intensities

Resende Junior, Alonso José de 05 December 2011 (has links)
O nitrogênio, dentre os nutrientes, é o elemento que apresenta maior efeito sobre a produção de gramíneas forrageiras. As respostas da planta forrageira a adubação nitrogenada podem ser alteradas devido à condição, de área foliar remanescente e teores de nutrientes, que esta planta apresenta quando este nutriente é aplicado. Os objetivos deste trabalho foram avaliar as características morfogênicas e estruturais, o intervalo entre pastejos, acúmulo de forragem e os teores de nutrientes do capim Tanzânia submetido a distintas severidades de desfolhação e fertilidades contrastantes. Os tratamentos corresponderam a combinações entre três alturas de resíduo pós pastejo (20, 30 e 50 cm) e dos níveis de fertilidade de solo (sem adubação e com adubação equivalente a 500, 300 e 150 Kg/ha de nitrogênio, K2O e P2O5 respectivamente), totalizando seis tratamentos sendo que cada tratamento contou com cinco repetições dispostas em blocos totalizando 30 unidades experimentais. Cada unidade experimental correspondia a um piquete de 400 m2. O pastejo foi efetuado quando o dossel forrageiro interceptava 95% da luz incidente. A morfogênese foi avaliada pelas seguintes características: taxa de aparecimento de folhas (TApF), filocrono (FIL), taxa de alongamento de folhas (TAlF), taxa de alongamento de colmos (TAlC), taxa de senescência de folhas (TSeF), duração de vida da folha (DVF), comprimento final da folha (CFF), número de folhas vivas por perfilho (NFV), número de folhas em expansão por perfilho (NFEx), número de folhas expandidas por perfilho (NFE), número de folhas senescentes por perfilho (NFS) e comprimento do colmo (CC). Foram avaliados os teores de nutrientes presentes nas duas folhas recém-expandidas. A amostra foi composta pelo terço médio do limbo foliar de 100 folhas retiradas de 50 perfilhos sendo que a amostragem foi realizada na condição de pré pastejo nos meses de abril e maio de 2010. As adubações criaram um contraste nutricional entre os tratamentos avaliados. O tratamento adubado com maior severidade de desfolhação apresentou os melhores resultados quanto ao acúmulo líquido de forragem e taxas de alongamento foliar. Os resultados obtidos neste experimento indicam a possibilidade de melhoria da eficiência de pastejo e de produtividade animal quando alta fertilidade de solo é combinada a maior severidade de desfolhação. / Nitrogen is the most important nutrient regulating pasture production. Response to N fertilization depends on residual leaf area index and other nutrient availability. The aim of this study was to evaluate morphogenetic and structural characteristics, grazing interval, forage yield and nutritional status of Tanzania guinea grass under contrasting defoliation severities and fertilization rates. The six treatments evaluated were factorial combinations between three post grazing heights (20, 30 e 50 cm) and two fertilization rates (unfertilized and fertilized with 500, 300 and 150 kg/ha of nitrogen, K2O e P2O5 respectively), arranged in five completed blocks, totaling 30 paddocks (experimental units) of 400 m² each.25 beef cattle animals were introduced into paddocks to graze every time sward reached 95% of light interception.Measured responses were leaf appearance rate, phyllochron, leaf elongation rate, stem elongation rate, leaf senescence rate, leaf life span, leaf mature length, live leafs per tiller, elongating leafs per tiller, mature leafs per tiller,senescent leafs per tiller and stem length.Nutritional status was measured in the two younger mature leavesof each tiller, considering 100 leaves sampled from 50 tillers of each paddockbetween May and April 2010. Fertilized and unfertilized treatments presented contrasting nutritional status. A high fertilization level combined with the lowest post grazing height resulted in the higher forage yields and leaf elongation rates. The results point to the possibility of enhancing grazing efficiency and animal production when high fertilizations are combined with high grazing intensity
153

Eficiência da área de sombreamento artificial no bem-estar de novilhas leiteiras criadas a pasto / Artificial shadow area efficiency in milk heifers welfare in pastures

Mellace, Elisabete Maria 17 June 2009 (has links)
Este estudo teve como objetivo avaliar e quantificar o efeito do sombreamento artificial proporcionado por diferentes áreas de sombra sobre a fisiologia e o comportamento de novilhas leiteiras, em ambiente de pastagens. A pesquisa foi realizada no período de fevereiro a abril de 2008. A área experimental foi dividida em 20 parcelas adjacentes com 84m² para os tratamentos 1, 2 e 3 e com 70m² para os tratamentos 4 e 5. Foram comparados a testemunha (tratamento 1, sem sombra) com 4 áreas de sombreamento por animal, tratamento 2 (com 1,5m²), tratamento 3 (3,0m²), tratamento 4 (5,0m²) e tratamento 5 (8,0m²), As dimensões dos abrigos foram 1,0m x 1,5m x 3,5m (largura, comprimento e altura) (1,5m² de sombra.animal-1), 1,5m x 2,0m x 3,5m (3,0m² de sombra.animal-1), 2,0m x 2,5m x 3,5m (5,0m² de sombra.animal-1) e 2,0m x 4,0m x 3,5m (8,0m² de sombra.animal-1), sem paredes laterais. Foram utilizadas 20 novilhas mestiças, 3/4 Jersey, ½ Holandesa e Jersey e Holandesas puras, com idade entre 12 e 25 meses e peso médio variando de 240 a 360kg, pareadas em função da uniformidade de peso e idade. As novilhas permaneciam em piquetes de Penissetum purpureum e complementação da dieta no cocho, durante a noite e após as 8:00 horas eram conduzidas para as parcelas. A Tgn foi registrada por um minidatalogger da marca LOGEN LS 8856 ALPAX. As variáveis meteorológicas foram obtidas no posto agrometeorológico da ESALQ/USP. Durante nove dias não consecutivos foram registradas FR e TS. As observações comportamentais foram realizadas em dias não consecutivos (nove dias) no período das 10:00 ás 16:00 horas pelo método focal. As condições ambientais em 66,7% do período da pesquisa foram em condição de estresse térmico para as novilhas. Os valores de FR e TS foram menores sob a maior área de sombra (P<0,05) e semelhantes entre os 1,5m², 3,5m² e 5,0m² (P>0,05). Houve correlação da Tgn com a FR e a TS. Não foram observadas alterações comportamentais entre os tratamentos, os animais ficaram sob as sombras nas horas mais quentes do dia, preferencialmente em pé, o comportamento seguiu os padrões conhecidos para bovinos. Para novilhas leiteiras a melhor área de sombreamento artificial é de 3m². / This study had as objective to evaluate and quantify the effect of artificial shading proportioned by different shadow areas under physiology and behavior of milk heifers, in pastures. Research was realized in the period from February to April, 2008. Experimental area was divided in 20 adjacent parcels with 84m2 to treatments 1, 2 and 3 and with 70m2 to treatments 4 and 5. Were compared witness (treatment 1, no shadow) with 4 shading areas per animal, treatment 2 (with 1,5 m²), treatment 3 (3,0 m²), treatment 4 (5,0 m²) and treatment 5 (8,0 m²). Shelters dimensions were 1,0m x 1,5m x 3,5m (width, length and height) (1,5m² of shade.animal-1), 1,5m x 2,0m x 3,5m (3,0m² of shade.animal-1), 2,0m x 2,5m x 3,5m (5,0m² of shade.animal-1) and 2,0m x 4,0m x 3,5m (8,0m² of shade.animal-1), without walls in the sides. Twenty crossbred heifers were used, 3/4 Jersey, ½ Holstein and pure Jersey and Holstein, with ages among 12 and 25 months and average weight varying from 240 to 360 kg, paired in function of weight and age uniformity. Heifers remained in Penissetum purpureum paddocks and had a diet complementation in the trough, during the period of night and after 8:00am they were conducted to the parcels. Tgn was registered by a minidatalogger from LOGEN LS 8856 ALPAX trend. Meteorological variables were obtained in the agrometeorological post from ESALQ/USP. During nine non consecutive days were registered FR and TS. Behavioral observations were realized in non consecutive days (nine days) in the period from 10:00am to 16:00pm by the focal method. 66,7% of environmental conditions in the period of research were in thermal stress conditions to the heifers. Values of FR and TS were minor under the major area of (P<0,05) and similar among 1,5m², 3,5m² and 5,0m² (P>0,05). There was a correlation of Tgn with FR and TS. Behavioral alterations among the treatments were not observed, animals stayed under the shadow in the hotter hours of the day, preferably on foot, behavior followed the known patters to bovine. For milk heifers the better of artificial shading area is 3m².
154

Digital Methods for Soil Mapping and Fertilizer Management in Oil Palm

Alberto Martinez (6617777) 10 June 2019 (has links)
<p>Oil palm (<i>Elaeis guineensis</i> Jacq.) is the world’s leading source of vegetable oil and an important driver of rural economic activity in Southeast Asia, West Africa, and the equatorial region of Latin America. In the Llanos region of Colombia, palm oil production is additionally an important vehicle for legal employment and social stability in a region deeply affected by the country’s longstanding and recently-concluded armed conflict. The economic viability of palm oil production is thus of great interest to both those directly employed in the industry and to the larger society around them, and yet oil palm remains a relatively understudied cropping system.</p> <p>Spending on fertilizer is one of the largest costs in palm oil production, and plantations face considerable pressure to apply fertilizer as efficiently as possible in order to maintain the profitability of their operations. However, developing strategies for optimizing fertilizer applications in oil palm can be considerably challenging given the particular characteristics of palm oil production systems. Oil palm has a typical life-cycle of 25 years, with harvesting done manually approximately every fifteen days for the duration of the palms productive life-cycle. The morphology of oil palm’s reproductive system makes it possible for environmental changes to affect yield in irregular ways, with the same soil or climate-related stressors having the potential to affect yields either immediately or multiple years after the event. It can therefore be difficult for plantations to link changes in yield patterns to individual management changes or environmental factors. Additionally, since unlike all other major oilseeds oil palms must be harvested manually, plantation managers do not have access to the kind of detailed yield data made possible by mechanized harvesting equipment, but must rely on much more irregular and coarser-resolution information to examine yield variability within plantations. Understanding how the particular soil conditions and fertilizer management history of an individual oil palm plantation drive variability in yields requires employing innovative approaches to maximize the insights to be learned from the available data. </p> <p> For this study, we worked with a 5,220 hectare oil palm plantation in the Colombian Llanos, in the municipality of Villanueva, Casanare. Despite uniform fertilizer applications and management practices, along with uniform climatic conditions within the plantation, significant yield variability existed within the plantation, with plantation managers initially unable to determine the underlying causes. We proposed and evaluated a methodology for using digital terrain and soil mapping for generating continuous soil data within an oil palm production system, based on Functional Soil Mapping (FSM) methods using the SRTM Global Digital Elevation model and geo-referenced soil sampling, with the goal of identifying soil physical, chemical and hydrological properties that could be directly linked to different yield responses to fertilizer application at the field scale. Furthermore, the economic implications for the plantation of infield variability in yield response to fertilizer arising from variation in soil properties were examined. </p> <p>The perennial nature and particularities in reproductive morphology of oil palm, including an approximately 8-10 year growth period before mature yields are reached, mean that developing site-specific yield response curves to different nutrient application levels in oil palm requires extensive time and resources. The PORIM model, developed by the Malaysian Palm Oil Board (MPOB) across multiple decades of extensive and continuous field testing, is one of the most commonly used methods by which plantations can estimate yield response at different levels of fertilizer application. Traditionally, the PORIM model is run by using site-specific low-resolution vector-layer soil analysis to adjust various parameters in multiple equation systems developed using statistical methods and many decades worth of field tests by the MPOB. In this study, the PORIM model is used as the basis for a methodology to employ a precision approach to fertilizer management in oil palm using high-resolution raster-layer soil property maps and a constrained-optimization model programmed in the General Algebraic Modeling System (GAMS). </p>
155

Niche Modeling of the economical important Mahanarva species in South and Central America (HEMIPTERA, CERCOPIDAE)

Sch?bel, Christian 22 February 2018 (has links)
Submitted by PPG Zoologia (zoologia-pg@pucrs.br) on 2018-04-20T12:08:51Z No. of bitstreams: 1 Disserta??o corre??o final - Christian.pdf: 2735367 bytes, checksum: 73fdc67c9898d886fdbd0e0cce1dfad3 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-05-08T16:47:52Z (GMT) No. of bitstreams: 1 Disserta??o corre??o final - Christian.pdf: 2735367 bytes, checksum: 73fdc67c9898d886fdbd0e0cce1dfad3 (MD5) / Made available in DSpace on 2018-05-08T16:53:43Z (GMT). No. of bitstreams: 1 Disserta??o corre??o final - Christian.pdf: 2735367 bytes, checksum: 73fdc67c9898d886fdbd0e0cce1dfad3 (MD5) Previous issue date: 2018-02-22 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Mahanarva fimbriolata, M. spectabilis, M. liturata and M. posticata (Hemiptera: Cercopidae) s?o conhecidas como pragas de planta??es de cana-de-a??car e pastagem em todo Brasil. Por alimentarem-se diretamente da seiva das plantas, esses cercop?deos causam fitotoxicidade e devido a isso diminuem a produ??o. A modelagem da distribui??o de esp?cies permite analisar a poss?vel occurencia das quatro esp?cies na Am?rica do Sul e Central. Para criar modelos de distribui??o de esp?cies foram utilizados em R, os algoritmos Bioclim, Domain, diferentes modelos lineares generalizados e Maxent. Nesses modelos foram utilizadas vari?veis bioclim?ticas atuais e futuras, al?m da eleva??o e outras vari?veis agr?colas. As vari?veis clim?ticas futuras s?o para os anos 2050 e 2070 com diferentes repentant concentration pathways. As esp?cies apresentam habitats adequados em diferentes pa?ses da Am?rica do Sul e Central, onde as planta??es de cana-de-a??car s?o abundantes. Os resultados das an?lises clim?ticas futuras n?o apresentaram diferen?as em rela??o ?s an?lises clim?ticas atuais. No geral, o algoritmo Maxent mostrou os maiores valores de AUC e o Bioclim os menores. As vari?veis que mais contribu?ram para os modelos s?o: eleva??o, isothermality e diferentes vari?veis de precipita??o. As mudan?as clim?ticas e ciclos de vida de insetos adicionais n?o t?m impacto em habitats adequados dos insetos. Em geral, o Maxent ? o melhor algoritmo para realizar modelos de distribui??o de esp?cies com um n?mero baixo de pontos de ocorr?ncia e an?lises de mudan?as clim?ticas. / Mahanarva fimbriolata, M. spectabilis, M. liturata and M. posticata (Hemiptera: Cercopidae) are known pests for sugarcane and pasture plantations throughout Brazil. By direct sap feeding on the plants they cause phytotoxicity and due to this they decrease the production of plantations. With species distribution modeling it is possible to analyze the possible occurence of the four species in South and Central America. To create species distribution models the algorithms Bioclim, Domain, different generalized linear models and Maxent were used in R. For those models current and future bioclimatic variables as well as elevation and other agricultural variables were used. The future climatic variables are for the years 2050 and 2070 with different repentant concentration pathways. The species show suitable habitats in different countries in South and Central America where sugarcane plantations are abundant. The results of the future climate analyzes do not show differences compared to the current climate analyzes. Overall the Maxent algorithm showed the highest AUC scores and Bioclim the lowest. The variables which contributed the most to the models are elevation, isothermality and different precipitation variables. Climate change and therefore additional insect lifecycles do not have an impact on the insect?s suitable habitats. Overall Maxent is the best algorithm to perform species distribution models with a low number of occurrence points and for climate change analyzes.
156

Atributos físicos e químicos do solo sob diferentes sistemas de manejo em áreas de ecótono Cerrado – Amazônia

Reis, Amanda da Silva 19 February 2018 (has links)
Os indicadores de qualidade do solo são propriedades mensuráveis (quantitativas ou qualitativas) que vão permitir caracterizar, avaliar e acompanhar as alterações ocorridas em dado ecossistema. Esses indicadores podem ser físicos, químicos biológicos e servem para quantificar as alterações ocorridas no solo. O presente estudo parte da hipótese que existe diferença entre sistemas de manejo adotados em diferentes tipos de solos. Foram avaliadas dez áreas, cada uma compreende um sistema de manejo, que estão divididas em duas classes de solo (Argissolo Vermelho e Neossolo Quartzarênico) com cinco sistemas de manejo (1-silvipastoril com 30% de sombreamento; 2- silvipastoril com 60% de sombreamento, 3- capoeira; 4- mata nativa secundária; 5- pastagem com manejo convencional). O estudo foi realizado na Escola de Medicina Veterinária e Zootecnia (EMVZ) da Universidade Federal do Tocantins (UFT), Araguaína-TO. Para avaliar os atributos químicos foi realizada a amostragem da área coletas foram realizadas nas profundidades de 0-10, 10-20 e 20-40 cm. Os atributos analisados foram pH, P, K+, Ca²+, Mg²+, H + Al³+, Al³+, soma de bases (SB), capacidade de troca catiônica (CTC) efetiva, CTC a pH 7, saturação por bases (V%), saturação por alumínio (m%). Os dados foram submetidos a análise de componentes principais e posteriormente a análise de variância e teste de Tukey (p< 0,05) para comparação de médias. Constatou-se que houveram pequenas mudanças nos atributos analisados dentro dos sistemas de manejo no Neossolo, no entanto o sistema Silvipastoril com 30% de sombreamento mostrou-se mais adequado, uma vez que elevou os valores de pH, e cátions essenciais do solo; enquanto que no Argissolo os sistemas silvipastoril com 60% de sombreamento e pastagem convencional apresentaram maiores médias nos atributos analisados, os colocando como os melhores sistemas estudados. Pana analisar os atributos físicos do solo foram coletadas dez amostras de solo indeformadas para quantificar a densidade do solo e porosidade total. Para determinação da textura e matéria orgânica (MO), foi realizada amostragem em duas profundidades 0-10 e 10-20 cm. Na determinação do estoque de carbono (EC) utilizou-se os valores do MO e DA para estimar os valores de EC. Os dados de textura, MO e EC foram submetidos a análise estatística e teste de comparação múltiplas de médias, Tukey (p< 0,05), os dados referentes à densidade do solo e porosidade total. No Neossolo Quartzarênico os diferentes sistemas de manejo não alteraram os atributos físicos avaliados, quando comparado a área de referência, porém, a área 1 apresentou melhor incremento no EC e MO, o que pode torna-lo mais eficiente para esse tipo de solo. No Argissolo Vermelho o sistema 2 teve um maior incremento EC e, portanto, MO, proporcionou melhoria nos atributos analisados. / Soil quality indicators are measurable (quantitative or qualitative) properties that will allow you to characterize, evaluate and monitor the changes that have occurred in the given ecosystem. These indicators can be physical, biological chemists and are used to quantify the soil changes. This study is part of the hypothesis that there is a difference between management systems adopted in different types of soils. Ten areas were evaluated, each comprising a management system, which are divided into two soil classes (Ultisol and Entisol Quartzipsamment) with five management systems (1-silvipastoril with 30% shading; 2-silvipastoril with 60% of shading, 3-capoeira; 4-native secondary Mata; 5-pasture with conventional handling). The study was carried out at the School of Veterinary Medicine and Animal Science (EMVZ) of the Federal University of Tocantins (UFT), Araguaína-to. To evaluate the chemical attributes was performed sampling the area collections were carried out at the depths of 0-10, 10-20 and 20-40 cm. The analyzed attributes were PH, P, K +, Ca ² +, Mg ² +, H + Al ³ +, Al ³ +, Sum of bases (SB), cationic exchange Capacity (CTC) Effective, CTC at PH 7, base saturation (V%), aluminium saturation (m%). The data were subjected to analysis of main components and subsequently analysis of variance and test of Tukey (p < 0.05) for comparison of averages. It was found that there were small changes in the attributes analyzed within the management systems in the Neossolo, however the Silvipastoril system with 30% shading proved to be more appropriate, since it elevated the PH values, and essential cations of the soil; While in upper the silvipastoril systems with 60% shading and conventional pasture showed higher averages in the analyzed attributes, placing them as the best studied systems. Pana analyze the physical attributes of soil were collected ten undeformed soil samples to quantify soil density and total porosity. For the determination of the texture and organic matter (MO), sampling was carried out at two depths 0-10 and 10-20 cm. In the determination of the carbon Stock (EC) The values of the Mo and of the value were used to estimate the EC values. The texture data, MO and EC were subjected to statistical analysis and multiple comparison test of averages, Tukey (p < 0.05), data pertaining to soil density and total porosity. In the Neossolo Quartzarênico the different management systems did not change the physical attributes evaluated, when compared to the reference area, however, area 1 presented a better increase in the EC and MO, which can make it more efficient for this type of soil. In the red upper System 2 had a higher EC increment and therefore MO, provided improvement in the analyzed attributes.
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Analyse des Entscheidungsverhaltens landwirtschaftlicher Unternehmer: Anwendung von Discrete Choice Experimenten in den Bereichen Tierwohl, Weidehaltung und Ackerbau / Analysis of farmers decision behaviour: Application of discrete choice experiments in different agricultural decision situations

Danne, Michael 07 May 2018 (has links)
No description available.
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Palynologická analýza pylu sebraného včelou medonosnou (Apis mellifera) v oblasti Praha-západ / Pallynological Analysis of Pollen Collected by Honey Bee (Apis mellifera) in the Prague-West District

Štrachová, Markéta January 2018 (has links)
Title of the Thesis The Palynological Analysis of the Pollen Collected by Honey Bee (Apis mellifera) in the Prague-West Area Abstract This diploma thesis underlines the importance and significance of bee pasture. The first part of the thesis contains the presentation of the honey bee (Apis mellifera). It also describes the structure of the pollen grain, pollen as such, and its use regarding bee nutrition, the factors determining bee harvest of pollen, the means of its collecting and the use of bee pollen and bee bread. Furthermore, there are characteristics of pollen pasture in the time of early spring, spring, summer, late summer and autumn. The second part is dedicated to the palynological analysis of the area of Prague-West, Úhonice. The diploma thesis contains the evaluation of the food offer for the bees from the aforementioned location, and the summary of pollen-yielding plants blooming between 1 April 2017 and 27 June 2017. The sampling of pollen balls, which had taken place within this time span, provided the initial information about the nutrition of bees as well as the data regarding the diversity of plant species in the chosen location. In total, the samples contained 98 kinds of plants, out of which 31 were dominantly present above the limit of 6 percent. The longest lasting source of pollen was...
159

Substituição da Brachiaria decumbens pela Brachiaria brizantha cv. Marandu em sistema de plantio direto /

Campidelli, Oscar, 1970- January 2006 (has links)
Orientador: Sérgio Lázaro de Lima / Banca: Sérgio Pascoal de Campos / Banca: Ciniro Costa / Resumo: O presente trabalho objetivou avaliar a produção da Brachiaria brizantha Stapf cv. Marandu semeada na palhada da Brachiaria decumbens. O experimento foi instalado em condição de campo, no ano agrícola 2005/06, na Fazenda Experimental Lageado da Faculdade de Ciências Agronômicas - Campus de Botucatu/UNESP. O delineamento experimental foi o de blocos casualizados, com cinco repetições. As parcelas foram implantadas com espaçamento único de 15 cm entre linhas. Os tratamentos aplicados foram: tratamento 1 (T1 - dessecou-se a B. decumbens e aplicou-se 6 Lha-1 de glifosato e 30 dias depois aplicou-se uma subdosagem com 2 Lha-1 e após 2 dias efetuo-se a semeadura da B. brizantha, com 20 kgha-1 de semente), tratamento 2 (T2 - aplicou-se 6 Lha-1 de glifosato e imediatamente fez-se a semeadura da B. brizantha, com 20 kgha-1 de semente), tratamento 3 (T3 - fez-se a semeadura da B. brizantha, com 20 kgha-1 de semente e imediatamente aplica-se 6 Lha-1 de glifosato), e tratamento 4 (T4 - aplicou-se 6 Lha-1 de glifosato e após 2 dias fez-se a semeadura da B. brizantha com 20 kgha-1 de semente). Foram avaliados a cobertura morta proporcionada pela B. decumbens sobre o solo e o percentual de cobertura verde da Brachiaria brizantha, bem como sua matéria verde e seca, aos 30, 50 e 70 dias após semeadura (DAS). A quantidade de matéria morta cobrindo o solo aos 30, 50 e 70 dias após a semeadura (DAS), da Brachiaria brizantha, apresentou resultados negativos para a germinação, emergência, produção de massa verde e seca e porcentagem de cobertura verde, da mesma, nos tratamentos T2, T3 e T4, e um melhor resultado para o T1. Desta forma, pode- 2 se concluir que o melhor manejo é dessecar a cultura antecessora 30 dias ou mais, antes da semeadura da nova cultura. / Abstract: The present research aimed at to evaluate the production of Brachiaria brizantha Stapf cv. Marandu sowed in the palhada of the Brachiaria decumbens. The experiment was installed in field condition, in the agricultural year 2005/06, in Fazenda Experimental Lageado da Faculdade de Ciências Agronômicas - Campus de Botucatu / UNESP. The treatments were set as a complete randomized experiment, with five repetitions. The portions were implanted with only spacing of 15 cm among lines. The applied treatments were: treatment 1 (T1 - the B. decumbens was desiccated and it was applied 6 Lha-1 of glifosato and 30 days later a dosage was applied with 2 Lha-1 and after 2 days make her the sowing of B. brizantha, with 20 seed kgha-1), treatment 2 (T2 - 6 Lha-1 of glifosato was applied and immediately it was made the sowing of B. brizantha, with 20 seed kgha-1), treatment 3 (T3- it was made the sowing of B. brizantha, with 20 seed kgha-1 and immediately 6 Lha-1 of glifosato is applied), and treatment 4 (T4 - 6 Lha-1 of glifosato was applied and after 2 days it was made the sowing of B. brizantha with 20 seed kgha-1). They were appraised the proportionate covering for B. decumbens on the soil and the percentage of green covering of the B. brizantha, as well as his green and dry matter, to the 30, 50 and 70 days after sowing (DAS). The amount of dead matter covering the soil to the 30, 50 and 70 days after the sowing (DAS), of the Brachiaria brizantha, it presented negative results for the germination, emergency, production of green and dry mass and percentage of green covering, of the same, in the treatments T2, T3 and T4, and a better result for T1. This way, it can be 4 concluded that the best handling is to desiccate the culture predecessor 30 days or plus, before the sowing of the new culture. / Mestre
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Ocorrência de Escherichia coli O157:H7 em bovinos abatidos em estabelecimento habilitado à exportação na cidade de Barretos - SP, Brasil /

Prata, Camila Barbieri. January 2009 (has links)
Orientador: Manoel Victor Franco Lemos / Banca: Fernando Antonio de Ávila / Banca: Felipe Perecin / Resumo: Escherichia coli O157:H7 é uma cepa de importância crescente por estar associada a vários surtos graves de doença em humanos, a maioria derivada do consumo de carne bovina crua ou mal cozida. Os bovinos constituem seu reservatório mais importante, aventando-se a hipótese de que mudanças do regime alimentar em confinamentos atuariam favoravelmente ao aparecimento de cepas shigatoxigênicas. Neste estudo objetivou-se verificar, comparativamente durante o abate, a prevalência desse sorotipo e o comportamento de métodos indicadores como a contagem total de microrganismos viáveis (CTMV) e de contaminação fecal - coliformes totais e E. coli, em amostras de fezes e em carcaças de bovinos terminados a pasto e em confinamento, possibilitando a disponibilização de subsídios necessários aos programas de Análise de Perigos e Pontos Críticos de Controle (APPCC) e de Análise de Risco (RA), empregados na redução do risco de doenças transmitidas por alimentos. Identificados os lotes de acordo com a terminação (dez de cada tipo), desses foram aleatoriamente colhidas e analisadas 100 amostras de suabe retal, 100 amostras de carcaças e 67 amostras de "recortes" da desossa (carne industrial) utilizando-se, para a E. coli O157- H7, técnica automatizada de PCR. À exceção de uma única amostra de recortes (0,37%), as demais, tanto de fezes quanto de carcaças, foram negativas para a cepa pesquisada. Além de contatar-se uma prevalência muito baixa, não se evidenciou diferenças entre os tipos de terminação dos animais. Os resultados dos indicadores - CTMV, de coliformes totais e E. coli, foram considerados aceitáveis em 91%, 85% e 93% das amostras, respectivamente, oferecendo suporte e concordância com a baixa prevalência encontrada. / Abstract: Escherichia coli O157:H7 is an important strain that has been associated with outbreaks of serious disease in humans, most being derived from consumption of raw or poorly cooked beef. It is likely that cattle are an important reservoir, suggesting the possibility that changes in feedlot diet favor the emergence of shigatoxigenic strains of E. coli. This study is intended to verify, comparatively during bovine slaughter, the occurrence of E. coli O157:H7 associated with the sampling results obtained by means of general indicator methods (total viable count) and fecal contamination indicators (coliforms and E. coli). Samples will be taken from both excreta and carcasses of cattle finished either on pasture or feedlot, allowing the provision of subsidies necessary for Hazard Analysis and Critical Control Points (HACCP) and Risk Analysis (RA) programs and applied in the reduction of the risk of foodborne diseases. After identification of batches according to the type of finishing (feedlot or pasture), samples were randomly collected and analyzed. 100 rectal swabs, 100 samples from carcasses sponging, and 67 samples of "sliced meat" from the boning room (industrial meat). An automatic PCR technique for detection of E. coli O157:H7 was used. Except for one sample of sliced meat (0.37%), all others, both for excreta and carcasses, were negative for the O157:H7 E. coli strain. There were no significant differences in prevalence between the types of cattle finishing of the animals. The results of the indicators methods (TVC, coliforms and E. coli); were considered acceptable in 91%, 85% and 93% of tested samples, respectively, supporting and in agreement with low prevalence of O157:H7 found. / Mestre

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