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CONTROLE DA ACIDEZ DO SOLO EM SISTEMAS DE PRODUÇÃO DE AZEVÉM ANUAL E MILHO SILAGEM: ESTUDO EM MÉDIO PRAZO / Soil acidity control in systems production of annual ryegrass and maize silage: study in medium-termSantos, Jéssica Alves dos 20 February 2015 (has links)
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Previous issue date: 2015-02-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The liming is essential for building soil fertility, enabling exploitation more sustainable of production systems. However, the efficiency and the residual effect of lime used are dependent on the degree of soil disturbance, which has been distinguished in conservation production systems. The objectives of this work are (i) quantify the yields of dry matter (DM) and content crude protein (CP) in maize silage during the years 2008-2014; and (ii) evaluate
the changes in soil fertility attributes: active acidity (pH), potential acidity (H+Al), exchangeable acidity (Al3+) and base saturation (V) 24 and 60 months after of liming, in
different methods tillage and uses of annual ryegrass during the autumn-winter. The experiment was conducted in Castro (PR) in an Oxisol dystrophic clayey. The design
experimental was a randomized complete block design with split plots and four replications. In the plots were studied four methods of soil tillage: conventional tillage (CT), minimum tillage (MT), no-tillage (NT) and chiseled no-tillage (CNT). In the subplots were studied three
purposes of use of annual ryegrass: cover crop (CC), silage (S) and grazing of the dairy heifers in integrated crop-livestock (ICL). In medium-term, the tillage methods (CT, MT, NT, and CNT) do not influence the yield of DM and CP content of maize silage. The uses annual ryegrass for S and ICL not influence yield of DM and provide high CP in corn silage. Using the preceding crop just as CC provides least amount of benefits systems to annual ryegrass
production and maize silage. Lower acidity and higher V were observed in layer the 0-5 cm in NT. Compared to the NT, the CNT not improve the acidity and V. The annual ryegrass for the S and ICL provided, over time, decrease in the acidity of the soil in layers below 10 cm depth.
The NT combined with ICL provides improvement in soil acidity conditions after 60 months
after liming. / A correção da acidez é fundamental para a construção da fertilidade do solo, possibilitando a exploração mais sustentável dos sistemas de produção. Todavia, a eficiência e o efeito residual do corretivo utilizado são dependentes do grau de perturbação do solo, que tem sido distinto nos sistemas de produção. Os objetivos deste trabalho são (i) quantificar os rendimentos de matéria seca (MS) e teor de proteína bruta (PB) no milho silagem durante os anos 2008-2014; e (ii) avaliar as alterações nos atributos de fertilidade do solo: acidez ativa (pH), potencial (H+Al) e trocável (Al3+) e saturação por bases (V) aos 24 e 60 meses após a calagem, em diferentes métodos de preparo do solo e usos do azevém anual durante o outonoinverno. O experimento foi instalado no município de Castro (PR), em um Latossolo Bruno distrófico de textura argilosa. O delineamento experimental utilizado foi o de blocos completos casualizados, com parcelas subdivididas e quatro repetições. Nas parcelas (10 x 30 m) foram empregados quatro métodos de preparo do solo: cultivo convencional (CC), cultivo mínimo (CM), plantio direto (PD) e PD com subsolagem bianual (PDS). Nas subparcelas (10
x 10 m) foram estudadas três propósitos de uso do azevém anual: cobertura do solo (CS), silagem pré-secada (SPS) e pastejo animal em sistema integrado de produção agropecuária (SIPA). Em médio prazo, os métodos de preparo do solo (CC, CM, PD e PDS) não influenciam o rendimento de MS e teor de PB de milho silagem. Os usos de azevém anual para SPS e em SIPA não influenciam o rendimento de MS e proporcionam incremento nos
teores de PB no milho silagem. O uso da cultura antecessora apenas como CS proporciona menor quantidade de benefícios aos sistemas de produção de azevém anual e milho silagem. No decorrer do período, menor acidez e maior V foram observadas na camada de 0-5 cm no PD. Quando comparado ao PD, o PDS não proporcionou melhoria nas condições de acidez e V. O azevém anual destinado à SPS e SIPA proporcionou, ao longo do tempo, diminuição da acidez do solo nas camadas abaixo de 10 cm de profundidade. O PD aliado ao SIPA proporciona melhoria nas condições de acidez do solo após 60 meses da aplicação do calcário.
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Produção de milho e capins Marandu e Mombaça em função de modos de implantação do consórcio /Borghi, Emerson, 1978- January 2007 (has links)
Orientador: Carlos Alexandre Costa Crusciol / Banca: Ciro Antonio Rosolem / Banca: Francisco Antonio Monteiro / Banca: Paulo Cesar Ocheuze Trivelin / Banca: João Kluthcouski / Resumo: O trabalho de pesquisa teve por objetivo: 1) avaliar a produtividade de grãos da cultura de milho em épocas de consorciação com Brachiaria brizantha cv. Marandu e Panicum maximum cv. Mombaça em SPD; 2) avaliar o desempenho das plantas forrageiras consorciadas em épocas e a resposta à adubação nitrogenada aplicada após a colheita do milho, quanto à produtividade e valor nutritivo; 3) verificar, na B. brizantha, o acúmulo de nitrogênio total e proveniente do fertilizante nitrato de amônio (NPPF) com doses de nitrato de amônio (15NH4NO3) aplicado em cobertura nas plantas forrageiras após a colheita da cultura do milho; 4) avaliar o residual da adubação nitrogenada nas plantas forrageiras na cultura do milho cultivado em sucessão; 5)avaliar o aproveitamento do nitrogênio (15N), aplicado em cobertura na B. brizantha, pela cultura sucedânea do milho. Para atingir tais propósitos, foram conduzidos três estudos simultaneamente, conduzidos em condições de campo durante os anos agrícolas de 2003/04, 2004/05 e 2005/06 na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas - Campus de Botucatu, em NITOSSOLO VERMELHO Estruturado, cultivado em SPD. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições. No estudo I, os tratamentos foram: 1) cultivo do milho solteiro; 2) milho com Brachiaria brizantha cv. Marandu consorciada na semeadura; 3) milho com Brachiaria brizantha cv. Marandu consorciada na adubação de cobertura; 4) milho com Panicum maximum cv. Mombaça consorciado na semeadura; 5) milho com Panicum maximum cv. Mombaça consorciado na adubação de cobertura. No segundo e terceiro anos de condução do experimento (anos agrícolas 2004/05 e 2005/06), após a colheita da cultura do milho, foi aplicado nitrato de amônio em cobertura nas quantidades equivalentes a 0, 30, 60 e 120 kg ha-1 de N...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work aimed to: 1) evaluate corn grain yield under different intercropping epochs with Brachiaria brizantha cv. Marandu and Panicum maximum cv. Mombaça under no-tillage system; 2) evaluate the performance of the forages intercropped and the answer of these crops to nitrogen rates applied after corn harvest, considering the productivity and nutritional value; 3) verify, in B. brizantha, the total nitrogen accumulation and the nitrogen accumulated from the fertilizer ammonium nitrate (NPPF) under different ammonium nitrate rates (15NH4NO3) applied in the forages as cover crop after corn harvest; 4) evaluate the nitrogen profit (15N), applied as cover crop in B. brizantha, by corn cultivated in succession. To reach the proposed objectives, it was carried on three simultaneous studies, carriers on at field conditions, during the cropping years of 2003/04, 2004/05 and 2005/06 at Lageado Experimental Farm, College of Agricultural Sciences, in Botucatu, State of São Paulo, Brazil, in a structured Oxisol cultivated under no-tillage system. The experimental design was in blocks completely randomized, with four replicates. In the experiment I, the treatments were: 1) corn cultivated alone; 2) corn with Brachiaria brizantha cv. Marandu as consortium seeded at corn seeding; 3) corn with B. brizantha cv. Marandu as consortium seeded at corn cover fertilization; 4) corn with Panicum maximum cv. Mombaça as consortium seeded at corn seeding; 5) corn with P. maximum cv. Mombaça as consortium seeded at corn cover fertilization. In the second and third experimental years (2004/05 and 2005/06), after corn grain harvest, it was applied cover rates of ammonium nitrate, equivalent to 0, 30, 60 and 120 kg ha-1 of N. Only under B. brizantha were allocated micro parcels in which it was applied enriched ammonium nitrate (15NH4NO3), to evaluate the N recovery by Brachiaria ...(Complete abstract click electronic access below) / Doutor
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Influência do gado e da monocultura de eucalyptus sp. em florestas ripárias do sul do BrasilDe Marchi, Tiago Closs 11 January 2011 (has links)
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Previous issue date: 2011 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A mudança do uso da terra decorrente de atividades agrícolas provoca uma modificação na paisagem que leva à criação de fragmentos florestais isolados que se mantém imersos em uma matriz que pode apresentar uma maior ou menor agressividade de acordo com o seu uso. Este estudo foi realizado em duas fazendas vizinhas localizadas no município de Eldorado do Sul, RS. A Fazenda Terra Dura, pertence à empresa Celulose Riograndense S/A e a maior parte da área é utilizada para a monocultura de eucalipto (Eucalyptus spp.). Os remanescentes de floresta nativa estão exclusivamente associados aos diversos cursos d’água que cruzam a área e cercados pelo plantio de eucalipto de diversas idades e estágios de produção. A área é utilizada para o plantio de eucalipto há cerca de 30 anos e há 20 foi isolada do gado. A Fazenda Eldorado destina-se à criação extensiva de gado e sua cobertura vegetal é caracterizada por um predomínio de campo com fragmentos de florestas ripárias que o gado utiliza como local de pastejo e desedentação. Em cada uma das dez áreas selecionadas foram alocados dois transectos paralelos ao curso d’água a 20 metros de distância um do outro nos quais foram aleatorizadas cinco unidades amostrais de 10 x 10m para amostragem do componente arbóreo dos fragmentos. Em cada unidade amostral foram registradas a circunferência de todos os indivíduos com diâmetro a altura do peito maior ou igual a 5 cm (DAP ≥ 5cm). O componente juvenil foi amostrado em unidades amostrais de 5 x 5m concêntricas em cada parcela de 10 x 10m, onde foram amostrados todos os indivíduos com mais de um metro de altura e com menos de 5 cm de diâmetro e estimou-se sua altura total e seu diâmetro à altura do solo (DAS). A densidade e composição do estrato herbáceo foi amostrada em parcelas de 1 x 1 m concêntricas às unidades amostrais de 5 x 5 m. Nestas unidades amostrais foi removida toda vegetação de até 1 m de altura e identificadas taxonômicamente as espécies e separadas em formas de vida (árvore, arbusto, erva, gramíneas, pteridófita, trepadeiras, epífitos). Para avaliação do sub-bosque nos plantios de eucalipto foram selecionados quatro talhões onde foram alocados três transectos de 100 m de comprimento em diferentes distâncias da borda (5, 25 e 50 m) e dois transectos (5 e 25 m) para o interior da mata ciliar. Em cada transecto foram sorteadas cinco unidades amostrais de 5 x 5 m e amostrados todos os indivíduos juvenis utilizando os mesmos critérios anteriormente citados para este estrato. Nos fragmentos adjacentes aos plantios de eucalipto, foram encontradas 61 espécies para os adultos e 77 para os juvenis e o estoque de carbono estimado foi de 106 Mg.ha-1 para os indivíduos adultos e de 4,3 Mg.ha-1 para os herbáceos. Nas áreas com presença de gado foram amostradas 62 espécies para os adultos e 48 para juvenis, com um estoque de carbono de 85,5 Mg.ha-1 para adultos e 0,9 Mg.ha-1 para herbáceo. No sub-bosque dos plantios de eucalipto foram amostradas 32 espécies, sendo 16 exclusivas e 71 no interior da floresta ripária, com 55 exclusivas. Os resultados mostraram que florestas em pequenos fragmentos incorporados em plantações de eucalipto parecem ser melhor preservadas do que aqueles expostos à pecuária. Além disso, áreas com presença de gado apresentaram uma redução no estoque de carbono de 23,8% para o estrato arbóreo e de 79,4% no estrato herbáceo em relação às áreas sem a presença de gado. A plantação de eucalipto possui um importante papel, embora restrito devido ao curto período de corte das árvores, para a manutenção da diversidade de espécies de florestas nativas adjacentes em seu sub-bosque e podem atuar como uma catalizadoras da regeneração da vegetação nativa e na manutenção da diversidade local. / The change in land use due to agricultural activities causes a landscape change that leads to the creation of isolated forest fragments that remain embedded in a matrix that may present a greater or lesser aggressiveness according to their use. The environmental quality of this matrix can affect species composition and forest structure through several factors that impact the surrounding environment, but on the other hand, depending on its type, the array can act as an important source of biodiversity conservation. This study was conducted in two neighboring farms located in Eldorado do Sul, RS. Terra Dura Farm, owned by Celulose Riograndense S/A and most of the area is used for the monoculture of eucalyptus (Eucalyptus spp.). The remnants of native forest are exclusively associated with the various streams that cross the area and surrounded by eucalyptus plantations of various ages and stages of production. The area is used for the planting of eucalyptus during 30 years. The cattle was isolated 20 years ago. Eldorado Farm is intended for extensive cattle ranching and its vegetation is characterized by a predominance of field with fragments of riparian forests that livestock use for grazing. We survey ten riparian fragments, five in each farm, were allocated two transects parallel to the stream to 20 m away from each other in which five were randomized plots of 10 x 10 m sampling of the tree component of the fragments. In each sampling unit circumference were recorded for all individuals with diameter at breast height greater than or equal to 5 cm (DBH ≥ 5 cm). The juvenile component was sampled in 5 x 5 m plots concentric in each plot of 10 x 10 m was sampled all individuals with more than one meter in height and less than 5 cm in diameter and estimated its total height, and its diameter at ground level (DAS). The density and composition of the herbaceous layer was sampled in plots of 1 x 1 m plots of concentric to 5 x 5 m. In these sample units of all vegetation was removed up to 1 m high, which were taxonomically identified and separated in life forms (tree, shrub, herb, grass, fern, lianes and epiphytes). To evaluate the understory in the eucalyptus plantations were selected four plots were allocated three transects of 100 m length at different distances from the edge (5, 25 and 50 m) and two transects (5 and 25 m) into the riparian vegetation. In each transect were randomly selected five samples of 5 x 5 m and sampled all juveniles using the same criteria previously cited for this stratum. In fragments adjacent to eucalyptus plantations, 61 species were found for adults and 77 for juveniles and the estimated carbon storage was 106 Mg.ha-1 for adults and 4.3 Mg.ha-1 for the herbs. In areas with presence of cattle were sampled for 62 adults and 48 for juveniles, with a carbon stock of 85.5 Mg.ha-1 for adults and 0.9 Mg.ha-1 for herbaceous. In the understory of the eucalyptus plantations were found 32 species, with 16 exclusive and 71 within the riparian forest, with 55 exclusive. Our results showed that in small forest fragments embedded in eucalypt plantations seem to be better preserved than those exposed to livestock. In addition, areas with the presence of cattle showed a reduction in carbon stock of 23.8% for the upper stratum and 79.4% in the herbaceous layer compared to areas without the presence of livestock and the planting of eucalyptus has an important role, although limited, due to shortcut the trees for the maintenance of species diversity of native forest adjacent to their understory and can act as a catalyst of the regeneration of native vegetation and maintenance of local diversity.
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Dinâmica de comunidade de espécies arbóreas em manchas de Mata Atlântica com matrizes de pecuária e silvicultura de eucalipto no extremo sul do BrasilVier, Iliane Freitas de Souza 27 August 2013 (has links)
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Previous issue date: 2013-08-27 / CMPC - Celulose Riograndense / A vegetação do sul do Brasil é composta pelos biomas Pampa e Mata Atlântica. Nossas áreas de estudo situam-se próximo aos limites destes dois biomas, formando um mosaico campo-floresta. A pecuária e a silvicultura de eucalipto são atividades largamente difundidas ao longo destas formações. A mudança de manejo da matriz, da pecuária para a silvicultura de eucalipto, pode levar a alterações nas características autoecológicas de espécies arbóreas florestais. O estudo das características autoecológicas em ambientes com diferentes históricos de uso da terra pode ajudar a compreender como as espécies arbóreas respondem às alterações de habitat ou das condições ambientais. Este estudo objetiva analisar como atributos autoecológicos entre espécies arbóreas florestais variam segundo uma mudança de manejo da matriz no extremo sul da Mata Atlântica, de campos nativos com pecuária extensiva para plantações de eucaliptos sobre essas pastagens. De forma específica, pretende-se (i) determinar o efeito da mudança de manejo sobre atributos autoecológicos entre espécies, e havendo este efeito, (ii) que padrões de alteração autoecológica podem ser identificados entre espécies. De acordo com nossos resultados, a mudança de manejo da matriz da paisagem causou alterações nos padrões autoecológicos das espécies arbóreas. A amplitude destas variações foi diferente para cada espécie e dependeu de sua plasticidade fenotípica e das condições ambientais locais. A longo prazo, os padrões de alterações autoecológicas encontrados podem refletir uma mudança na composição de espécies em decorrência da mudança de manejo. / The vegetation of southern Brazil is composed of Pampa and Atlantic Rain Forest biomes. Our study areas are located near the boundaries of these two biomes, forming a 24 grassland-forest mosaic. The livestock and eucalyptus plantations are widely diffused throughout these formations. The change of matrix management, of livestock for eucalyptus plantations, can lead to changes in the autoecological attributes of forest tree species. The study of the autoecological attributes in environments with different historical of land use can help to understand how tree species respond to changes in habitat or environmental conditions. This study aims to analyze how autoecological attributes between forest tree species varies as a consequence of change in management matrix at the southern Atlantic Rain Forest, of grasslands with extensive livestock for eucalyptus plantations on these pastures. Specifically, we intend to (i) determine the effect of changing management on autoecological attributes among species, and having this effect, (ii) what patterns of autoecological change can be identified between species. According to our results, the change in management of landscape matrix caused changes in autoecological patterns of tree species. The extent of these variations was different for each species and depended on their phenotypic plasticity and local environmental conditions. Long-term, patterns of autoecological change found may reflect a change in species composition due to the change in management of landscape matrix.
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Nutrients dynamics in corn-Brachiaria intercropping systems / Dinâmica de nutrientes nos sistemas de consórcio milho-BrachiariaSilas Maciel de Oliveira 29 January 2018 (has links)
Corn (Zea mays L.) intercropped with Brachiaria spp. plays an important role in tropical agriculture management, providing residues or forage to areas intensively cropped. Although previous studies provide useful information about effects of intercropping on soil management and crop yield, a better understanding of how corn-Brachiaria intercropping systems impacts exogenous and endogenous nutrient dynamic is needed. Two experiments were performed in the both conventional and late planting season. In the first, corn and palisadegrass (Brachiaria brizantha cv. Marandu) monoculture were compared with two intercropping patterns, directed for production of residues or forage, with simulated animal grazing. Biomass, crop nitrogen (N) content, N derived from fertilizer and N budget were measured. Among farming systems, variable responses remained almost unchanged during period of simultaneous growth. After corn harvest, intercropping patterns achieved greater biomass (0.6-11 Mg ha-1) and N content (12-318 kg ha-1) relative to fallow preceded by corn monoculture, but it results in overall gains (pre and post-harvest) only to conventional planting season. N fertilizer recovery was not affected by intercropping patterns. When corn and Brachiaria were intercropped to establish pasture, simulated grazing after grain harvest had a tightly influence on N budget, approximately -221 kg ha-1. The second experiment investigated the influence of Brachiaria species on corn nutrients partitioning and their cycling after corn harvest. Biomass, N, phosphorus (P) and potassium (K) content were evaluated using corn intercropped with three species of Brachiaria (B. Brizantha cv Marandu, B. ruziziensis, and B. hybrid cultivar Mulato II, Convert HD 36) and corn monoculture. Biomass and nutrient content was not affect when corn was intercropped with Brachiaria species. After corn harvest, Brachiaria nutrient content and biomass yield were ranking from greater to lower following the order: B. brizantha > B. ruziziensis > B. convert. Relative with the corn monoculture, intercropping treatments enhanced the total biomass (corn + Brachiaria) and the nutrient accumulation only when planted at conventional season. Over 6 site-yr, benefits of intercropping appear after corn harvest, particularly at conventional planting season. Corn intercropped with Brachiaria species either had no effect N fertilizer recovery or affect N-fertilizer distribution within components of soil-plant system. Nonetheless, intercropping provide greater biomass accumulation after harvest compared with corn monoculture, resulting in larger nutrient content stored in plant component. Our results suggest a larger N requirements when crop-livestock activities was integrated. Corn intercropped with B. brizantha during conventional season was the best approach to enhanced crop yield and nutrient cycle for corn production systems. / O consórcio entre milho (Zea mays L) e espécies de Brachiaria spp. (syn. Urochloa spp.) desempenha importante função no manejo da agricultura tropical, produzir resíduos ou forragem em áreas intensivamente cultivadas. Apesar de estudos anteriores fornecerem valiosas informações sobre efeitos do consórcio sobre o manejo do solo e produção de biomassa, um melhor entendimento de como este sistema de cultivo afeta a dinâmica de nutrientes (exógenos ou endógeno) é necessário. Dois experimentos foram conduzidos durante a safra e segunda safra. No primeiro, os monocultivos de milho e braquiária (Brachiaria brizantha cv. Marandu) foram comparados com dois padrões de consórcio, direcionado a produção de resíduos ou forragem, com simulação do pastejo animal. Biomassa, acúmulo de nitrogênio (N), N- fertilizante e balanço de N foram avaliados. As variáveis respostas praticamente não foram afetadas pelos sistemas de cultivos durante o período de coexistência. Após a colheita do milho, os sistemas consórciados acumularam mais biomassa (0,6 -11 Mg ha-1) e N (12-318 kg ha-1) comparado ao pousio precedido pelo monocultivo de milho, apesar destes incrementos afetarem apenas o acúmulos totais (pré+pós-colheita) do cultivo de safra. A recuperação do N-fertilizante foi semelhante entre os sitemas de cultivo. Quando o consórcio objetivou a implantação de pasto, o pastejo simulado após a colheita do milho influênciou o balanço de N, com deficit de aproximadamente -221 kg ha-1.O segundo experimento foi conduzido para investigar a influência das espécies de Brachiaria sobre o particionamento de nutrientes no milho e a ciclagem pós-colheita de grãos. Produção de biomassa, quantidades de N, fósforo (P) e postássio (K) acumuladas foram avaliadas no monocultivo de milho e em três espécies de Brachiaria spp. (B. Brizantha cv Marandu, B. ruziziensis, and B. hibrido cultivar Mulato II, Convert HD 36) em consórcio com milho. Biomassa e acúmulo de nutrientes não foram afetados no consórcio do milho com as espécies de Brachiaria. Após a colheita do milho, o acúmulo de biomassa e nutrientes das espéceis de braquiária classificadas em ordem decrescente foram: B. brizantha > B. ruziziensis > B. convert. Comparado ao monocultivo de milho, o consórcio aumentou a biomassa total (milho+braquiária) e o acúmulo de nutrientes apenas quando cultivado na safra. Entre os 6 locais/anos, os benefícios do consórcio ocorreu após acolheita do milho, especialmente para o cultivo de safra. O milho consorciado com espécies de Brachiaria não afetou a recuperação do N-fertilizante nem sua distribuição nos componentes do sistema solo-planta. Entretanto, o consórcio proporcionou maior acúmulo de biomassa após a colheita do milho se comparado ao pousio precedido pelo monocultivo de milho, aumentando a porção de nutrientes alocados no compartimento planta do sistema. Nossos resultados sugerem que a integração entre atividades de lavoura e pastejo aumenta a demanda por N do sistema de produção. O consórcio entre milho e Brachiaria brizantha cv Marandu no cultivo de safra foi a melhor estratégia para aumentar a produção de biomassa e a ciclagem de nutrientes no sistema de produção do milho.
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Padrões de diversidade em comunidades de aves relacionadaos a varáveis de habitat em campos temperados do sudeste da América do SulDias, Rafael Antunes January 2013 (has links)
Indivíduos, populações e espécies tendem a usar e selecionar habitats de modo não-aleatório. Consequentemente, a perda e a degradação de habitats geram impactos distintos sobre os organismos dependendo de seus atributos. Os efeitos da perda de habitat são claros – os organismos são eliminados ou desalojados por falta de habitat ou baixo sucesso reprodutivo. As consequências da degradação de habitat são mais sutis, e resultam na incapacidade de um ecossistema sustentar determinadas espécies. Como a perda e a degradação de habitat reduzem a disponibilidade de nichos, espera-se que táxons ecologicamente especializados e com requerimentos estreitos de nicho sejam mais propensos à extinção que generalistas. Organismos que são negativamente afetados por perda e degradação de habitat em geral exibem porte muito grande ou muito pequeno, baixa mobilidade, baixa fecundidade, reduzido recrutamento e estreitos requerimentos de nicho. Campos temperados constituem ambientes particularmente afetados por perda e degradação de habitat. No sudeste da América do Sul, como em muitas outras regiões do planeta, a expansão da agricultura e silvicultura são os principais responsáveis pela perda de habitat campestre. Os remanescentes de vegetação natural são usados para criação de gado, estando sujeitos à degradação pelo sobrepastejo, pisoteio e técnicas de manejo. Avaliar como a perda e degradação de habitat afetam a diversidade de organismos campestres é vital para o desenvolvimento de estratégias de conservação e manejo. A presente tese tem por objetivo investigar como a degradação e perda de habitat induzidas pela pecuária e silvicultura afetam a diversidade e a composição das comunidades de aves. Inicialmente, exploramos as relações entre variáveis de habitat e a composição da comunidade de aves num gradiente de altura da vegetação determinado por pastejo em campos litorâneos do Rio Grande do Sul. Posteriormente, avaliamos como variações no relevo interagem com variáveis de habitat e afetam a diversidade de aves em áreas de pecuária na Campanha gaúcha. Finalmente, avaliamos de que forma a perda de habitat resultante do estabelecimento de plantações industriais de celulose em áreas de campo afeta a composição de comunidades de aves campestres. Nossos resultados demonstram que a degradação de habitat decorrente do manejo de gado em campo nativo afeta a comunidade de aves de forma diferencial. Aves adaptadas a campos ralos ou generalistas tendem a ser beneficiadas pelo pastejo, ao passo que as espécies associadas à vegetação alta e densa são desfavorecidas. As variações na topografia reduzem os impactos da degradação de habitat nos campos. Essas variações interagem com o habitat e afetam de forma diferencial os distintos componentes da diversidade. Por outro lado, a perda de habitat decorrente da silvicultura gera um impacto de maior magnitude, alterando a composição das comunidades de aves e favorecendo aves não-campestres. Nesse contexto, impedir que novas áreas de campo nativo sejam convertidas em plantações de árvores passa a ser imperativo. Embora o manejo do gado aumente a diversidade em nível de paisagem ao criar um mosaico de manchas de vegetação de alturas distintas, maior atenção deve ser dada à manutenção e recuperação de formações densas de herbáceas de grande porte. Isso somente pode ser assegurado através de mudanças no regime do pastejo ou do desenvolvimento de técnicas de manejo alternativas. / Individuals, populations and species tend to select habitats in a non-random way. Consequently, habitat loss and degradation will have different impacts on organisms according to their traits. The effects of habitat loss are straightforward – organisms are eliminated or displaced because of the inexistence of adequate habitat or of low breeding success. Effects of habitat degradation are more subtle and result in the reduction of the capacity of an ecosystem to support some subsets of species. Since habitat loss and degradation reduce niche availability, ecologically specialized taxa with narrow niche requirements are expected to be more extinction prone than habitat generalists. Temperate grasslands have been strongly impacted by habitat loss and degradation. In southeastern South America, the expansion of agriculture and industrial pulpwood plantations are the main sources of habitat loss. Remnants of natural grassland vegetation are used for livestock ranching, being subject to habitat degradation from overgrazing, trampling and inadequate management techniques. The evaluation of how habitat loss and degradation affect the diversity of grassland organisms is vital for the development of management and conservation techniques. The main goal of this thesis is to evaluate how habitat degradation and loss related to cattle ranching and pulpwood plantations affect the diversity and composition of bird communities. We began by exploring the relationship between habitat variables and the composition of the bird community along a gradient of vegetation height determined by grazing in coastal grasslands of the state of Rio Grande do Sul. We then assessed how variations in the relief interact with habitat variables e affect the diversity of birds in rangelands of the Campanha gaúcha. Finally, we evaluated how habitat loss related with grassland afforestation for pulpwood plantations affects the composition of grassland bird communities. Our results demonstrate that habitat degradation resulting from livestock ranching in natural grasslands affects bird communities in a differential way. Birds adapted to stunted grasslands or habitat generalists tend to benefit from grazing, whereas tall-grass specialists are negatively affected. Variations in topography are responsible for reducing the impacts of habitat degradation in grasslands. These variations interact with habitat and have a differential effect on distinct components of diversity. On the other hand, the magnitude of the impact of habitat loss from afforestation is larger, altering the composition of bird communities and favoring a series of non-grassland species. In this sense, protecting remaining grasslands from afforestation is imperative. Although cattle ranching increases diversity at the landscape level by creating a mosaic of vegetation patches of different height, more attention should be given in maintaining and recovering dense formations of tall grassland plants. This can only be achieved by changing grazing regimes or developing alternative management techniques.
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Monitoring Vegetation Change in the Kosciuszko Alpine Zone, AustraliaScherrer, Pascal, n/a January 2004 (has links)
This thesis examined vegetation change over the last 43 years in Australia's largest contiguous alpine area, the Kosciuszko alpine zone in south-eastern Australia. Using historical and current data about the state of the most common vegetation community, tall alpine herbfield, this thesis addressed the questions: (1) what were the patterns of change at the species/genera and life form levels during this time period; (2) what were the patterns of recovery, if recovery occurred, from anthropogenic disturbances such as livestock grazing or trampling by tourists; (3) what impacts did natural disturbances such as drought have on the vegetation and how does it compare to anthropogenic disturbances; and (4) What are the benefits, limitations and management considerations when using long-term data for assessing vegetation changes at the species/genera, life form and community levels? The Kosciuszko alpine zone has important economic, cultural and ecological values. It is of great scientific and biological importance, maintaining an assemblage of vegetation communities found nowhere else in the world. It is one of the few alpine regions in the world with deep loamy soils, and contains endemic flora and fauna and some of the few periglacial and glacial features in Australia. The area also forms the core of the Australian mainland's most important water catchment and is a popular tourist destination, offering a range of recreational opportunities. The vegetation of the Kosciuszko alpine zone is recovering from impacts of livestock grazing and is increasingly exposed to pressures from tourism and anthropogenic climate change. At the same time, natural disturbances such as drought and fire can influence the distribution, composition and diversity of plants. Thus, there is a need for detailed environmental data on this area in order to: (1) better understand ecological relationships; (2) understand existing and potential effects of recreational and management pressures on the region; (3) provide data against which future changes can be assessed; and (4) provide better information on many features of this area, including vegetation, for interpretation, education and management. The research in this thesis utilised three types of ecological information: (1) scientific long-term datasets; (2) photographic records; and (3) a comparison of disturbed and undisturbed vegetation. This research analysed data from one of the longest ongoing monitoring programs in the Australian Alps established by Alec Costin and Dane Wimbush in 1959. Permanent plots (6 transects and 30 photoquadrats) were established at two locations that differed in the time since grazing and have been repeatedly surveyed. Plots near Mt Kosciuszko had not been grazed for 15 years and had nearly complete vegetation cover in 1959, while plots near Mt Gungartan showed extensive impacts of grazing and associated activities which only ceased in 1958. Some transect data from 1959 to 1978 have been analysed by the original researchers. The research presented in this thesis extends this monitoring program with data from additional surveys in 1990, 1999 and 2002 and applies current methods of statistical evaluation, such as ordination techniques, to the whole data set for the first time. Results indicated that the recovery from livestock grazing and the effects of drought have been the main factors affecting vegetation. Recovery from livestock grazing at the three transects at Gungartan was slow and involved: (1) increasing genera diversity; (2) increasing vegetation cover; (3) decreasing amounts of bare ground; and (4) a directional change over time in species composition. Patterns of colonisation and species succession were also documented. In 2002, 44 years after the cessation of grazing, transects near Mt Gungartan had similar vegetation cover and genera diversity to the transects near Mt Kosciuszko, but cover by exposed rock remained higher. A drought in the 1960s resulted in a temporary increase of litter and a shift in the proportional cover of life forms, as grasses died and herb cover increased at both locations. Proportions of cover for life forms reverted to pre-drought levels within a few years. The results also highlighted the spatial variability of tall alpine herbfield. The photoquadrats were surveyed in the years 1959, 1964, 1968, 1978 and 2001 and are analysed for the first time in this thesis. After comparing a range of methods, visual assessment using a 130 point grid was found to be the most suitable technique to measure vegetation cover and genera diversity. At the 18 quadrats near Mt Gungartan, there was a pattern of increasing vegetation cover as bare areas were colonised by native cudweeds and the naturalized herb Acetosella vulgaris. Revegetation from within bare areas largely occurred by herb species, while graminoids and shrub species predominately colonised bare ground by lateral expansion from the edges, eventually replacing the colonising herbs. At the 12 quadrats near Mt Kosciuszko, vegetation cover was almost complete in all years surveyed except 1968, which was at the end of a six year drought. Similar to the results from the transect study, the drought caused an increase in litter at both locations as graminoid cover declined. Initially herb cover increased, potentially as a result of decreased competition from the graminoids and a nutrient spike from decaying litter, but as the drought became more severe, herb cover also declined. Graminoid cover rapidly recovered after the drought, reaching pre-drought levels by 1978, and was at similar levels in 2001. Herb cover continued to decline after peaking in 1964. The photoquadrat study also documented the longevity and growth rates of several species indicating that many taxa may persist for several decades. It further provided insights into replacement patterns amongst life forms. In addition to assessing vegetation change following livestock grazing and drought at the long-term plots, recovery from tourism impacts was examined by comparing vegetation and soils on a closed walking track, with that of adjacent undisturbed tall alpine herbfield at a series of 22 paired quadrats. Fifteen years after the track was closed there was limited success in restoration. Over a quarter of the closed track was still bare ground with non-native species the dominant vegetation. Plant species composition differed and vegetation height, soil nutrients and soil moisture were lower on the track which had a higher compaction level than adjacent natural vegetation. The results presented in this thesis highlight that tall alpine herbfield is characterised by nearly entire vegetation cover which is dominated by graminoids, followed by herbs and shrubs in the absence of disturbance by livestock grazing, trampling or drought. The studies also showed that under quot;average" conditions, the relative cover of herbs and graminoids remained fairly stable even though there can be considerable cycling between them. Spatial variability in terms of taxa composition was high. The only common introduced species in unrehabilitated sites was Acetosella vulgaris, which was effective at colonising bare ground but was eventually replaced by other native species. However, in areas actively rehabilitated, such as on the closed track, non-native species introduced during revegetation efforts still persist with high cover 15 years after their introduction. Monitoring of vegetation change is also important at the landscape scale. This thesis provides a review of the potential use, the limitations and the benefits of aerial photography to examine vegetation change in the Kosciuszko alpine zone. Numerous aerial photography runs have been flown over the area since the 1930s for government agencies, industry and the military. Some of these records have been used to map vegetation communities and eroding areas at a point in time. Other studies compared different types and scales of photographs, highlighting in particular the benefits and potential of large scale colour aerial photography to map alpine vegetation. However, despite their potential to assess vegetation change over time, a temporal comparison of vegetation in the Kosciuszko alpine zone from aerial photographs has not been completed to this date. Historical photographs may not be easy to locate or access and difficulties with vegetation classification may restrict the practicality of using historical aerial photographs to assess vegetation change. Despite these issues, aerial photography may provide a very useful and efficient tool to assess changes over time when applied appropriately, even in alpine environments. The development of digital classification techniques, the application of statistical measures of error to both methodology and data, and the application of geographic information systems are likely to further improve the practicality of historical aerial photographs for the detection of vegetation change and assist in overcoming some of the limitations. The results presented in this thesis highlight the need for limiting disturbance, for ongoing rehabilitation of disturbed areas and for long-term monitoring in the Kosciuszko alpine zone. The results contribute to our understanding of how vegetation may change in the future and may be affected by new land use activities and climate change. This type of information, which otherwise would require the establishment of long-term studies and years of monitoring, can assist land managers of this and other important protected areas. The study highlights how the use and expansion of already existing datasets to gather ecological information can save considerable money and time, providing valuable data for current and emerging issues.
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Management of stock effluent spillage from trucks in New ZealandThull, Jean-Paul January 1999 (has links)
The key objective of this multi-disciplinary research was to seek for feasible solutions to avoid effluent from livestock trucks spilling onto roads. Stock effluent spillage mainly poses road safety hazards and environmental damage, and also causes offence to road users and tourists. This task required reviewing previous institutional actions, assessing the power of the existing legislation, and evaluating the interests and attitudes of the stakeholder groups involved in the overall livestock supply chain. It was also necessary to consider politics, administration, public policy and economics, gaining the willing cooperation and confidence of the stakeholder groups through application of 'Soft Systems Methodology' (SSM). A key component was the creation of a 13 minute video and its associated brochure as a primary tool for a stakeholder educational awareness programme. It was necessary to analyse the complex relationships between livestock preparation prior to transport; effluent produced in-transit; and end product quality factors. Detailed information pertaining to the nature of livestock shipments by truck in the South Island of New Zealand had to be collected and verified. All the above information were fed into the calculation of an ideal network of in-transit effluent discharge sites on State Highways in the South Island of New Zealand. Assuming the adoption of best practice throughout the supply chain, it was possible to recommend sustainable solutions. The problem is amenable to solution. Adoption of a strong Industry Code of Practice, coupled with the construction of a strategic network of dump sites will enable the industry to avoid the heavy-handed legal consequences of allowing the status quo to continue.
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Modélisation spatiale des flux organiques et minéraux assurant la productivité durable des systèmes culture-élevage dans le sahel nigérien dans le sahel nigérienDjaby, Bakary 30 August 2010 (has links)
Lagriculture et lélevage occupent plus de 80% de la population des zones semi-arides de lAfrique de lOuest. Ces populations en tirent lessentiel de leur alimentation et de leurs revenus. Lun des problèmes de cette agriculture est la pauvreté des sols. Dans les pays comme le Niger où prédominent les agroécosystèmes culture- élevage, le rôle du bétail dans le recyclage de la matière organique et des éléments minéraux azote, phosphore et potassium peut constituer un atout pour laugmentation de la production agricole et animale et assurer une sécurité alimentaire durable. Les bilans et flux de ces matières organiques et éléments minéraux ont été utilisés comme indicateurs détat qui caractérisent la durabilité des systèmes de production.
Cette recherche porte sur lévaluation de ces flux et bilans organiques et minéraux aux échelles de l'exploitation agricole et du terroir dans le sud-ouest du Niger et la mise au point d'un indicateur de risque d'épuisement de la fertilité des terres des exploitations. L'étude porte sur trois terroirs agropastoraux de cette région couvrant une superficie de 500 km2 et sur un échantillon de 461 exploitations agropastorales. Les trois terroirs diffèrent essentiellement par leur pression agricole sur les terres, et par l'importance de l'élevage. Dans ces systèmes mixtes culture-élevage, la dualité de l'organisation spatiale qui les caractérise avec une gestion des cultures à l'échelle parcellaire centralisée à l'échelle de l'exploitation agricole et une gestion de l'élevage liée aux ressources pastorales communautaires de tout le terroir, fait que les modèles classiques de gestion sont confrontés à cette intégration d'échelles. Deux modèles ont été donc été utilisés pour lévaluation des flux et bilans partiels de N, P, K à des échelles différentes, celle de lexploitation agricole et celle des occupations de sol à léchelle du terroir. NUTMON, un modèle existant, est utilisé dans la détermination des flux à léchelle de lexploitation et de ses composants. La modélisation spatiale des flux à laide des systèmes dinformation géographique est opérée par articulation de NUTMON avec loutil NUTPAST développé dans cette thèse. Cet outil développé avec les systèmes d'information géographique prend en compte la dynamique spatio-temporelle de la végétation et du cheptel pour lévaluation de lingestion et de lexcrétion animale à léchelle de l'ensemble des occupations au sein d'un terroir. Un indicateur de risque intégré d'épuisement de la fertilité des terres a été conçu par exploitation à partir de variables de viabilité biophysiques relatives à l'utilisation de l'espace communautaire et de variables socio-économiques en lien avec la propriété des terres et du cheptel.
Les bilans partiels obtenus à l'échelle du terroir montrent globalement un équilibre entre les flux de gestion agricoles et de l'élevage à l'échelle des terres des exploitations, avec des valeurs de N,P,K moyens respectifs de 0.3 ± 0.6, 1.2 ±0.2, 0.9 ± 0.5 kg/ha.Ce bilan fait ressortir une grande disparité entre les exploitations qui montrent un bilan fortement positif chez les propriétaires de bétail et négatif chez les villageois ayant très peu de bétail. Les indicateurs de risque, basés sur les facteurs de pression sur les terres, les dotations en terres et bétail par habitant, laissent apparaître qu'en dépit d'une faible intensification par la fumure, la pression agricole sur les terres combinée à la faible dotation des exploitations agricoles en bétail est un facteur de risque d'épuisement relatif de la fertilité des sols très élevé à l'échelle des villages. Ce qui peut compromettre la durabilité de l'agriculture dans ces régions. Les problèmes d'utilisation des ressources communautaires au profit des seuls propriétaires de bétail posent le problème en termes de politique foncière dans ces agroécosystèmes. Avec la pression agricole actuelle, un autre mode d'intensification agricole est à rechercher avec une politique foncière d'accès aux ressources équitable.
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台灣畜產品導入生產履歷制度之研究—以豬隻生產為例 / The Research on Introduction of Agro-Biographical to Livestock Products in Taiwan - Take the Production of Pigs for Example詹正中, Chan, Cheng Chung Unknown Date (has links)
隨全球經濟發展、環保意識抬頭,以及食品安全衛生議題的日益重視,運用資訊科技維護人們食的安全已是一股不可擋的趨勢。本論文以資訊科技導入農產品生產控管以及維護生產品質、建立所謂農產履歷為研究目的;並以豬隻生產為例,深入探討在豬隻的生產過程中如何導入這新的科技技術,以及所搭配的生產履歷資訊平台。
文中首先針對所謂「農產履歷」作一詳細介紹,其中包括農產履歷的來由、推動農產履歷原因,以及目前各國所推展的農產履歷的現況如何。另外,在導入農產履歷之前也必須先了解所謂的「追溯系統」,在農產品整個生產過程中有哪些東西或流程是必須追蹤記錄。
本研究案在眾多的農產品中選擇以豬隻的生產過程作為導入「農產履歷」的研究標的其原因是因為:
1、 豬隻為我國農產品中產值最高。
2、 豬隻的生產過程短,從出生到送入屠宰僅六個半月。
3、 豬隻的生產過程中所需控管的項目較多,例如:飼料、添加劑、藥品、種源等。
本研究選擇以RFID作為農產履歷的記錄介質,在豬隻的身上打上所謂的RFID晶片,借以控管並記錄豬隻的生產過程,然,RFID晶片的外在形式有兩種,一種是外在耳掛式的晶片,稱之為「RFID耳標」,另ㄧ種是皮下植入式的,我們稱之為「植入式晶片」,本研究亦會針對這兩種不同的晶片同時導入加以評估,選擇一個最適合於豬隻生產所應搭配的形式。
除此之外,搭配RFID晶片所需的生產資訊系統,意即「畜牧場管理系統」也是不可或缺的,本研究案同時也針對了該管理系統有一深入的研究並提出該系統的設計理念,以及相關的系統設計方式,以期在本研究結束後能夠提出一套完整的豬隻生產過程的「農產履歷系統」。 / As the global economic development, environmental awareness and the attention to food safety, applying technology to safeguard people's food security is an irreversible trend. The purposes of this paper are to addresses the methods of introducing technology into agricultural production and control, and the maintenance of production quality. Take the production of pigs for example to investigate the introduction of technology to agricultural production as well as the operation and usage of information platform.
The thesis is aimed at so-called “agro-biographical”, containing the origins, the motivations and the current status of introduction of agro-biographical all around the world. On the other hand, the so-called "tracing system" is acknowledged before the introduction of agro-biography, which indicates what and how the detailed data should be included or recorded.
The case studies were selected in many agricultural production processes as a force to pigs "agro-biographical" because of the research subjects:
1. Pigs generate the highest value among Taiwan’s agricultural products and they are the necessity.
2. The production process of pigs is short, only six and a half months from birth to slaughter.
3. The more attentions are required to pigs production process and control, such as feed, additives, drugs, plant sources.
The study selected RFID as agro-biographical recording media, which control and record pig production process. These RFID chips are in two forms, one is the external ear TAGs, the so called “RFID ear TAG”, and the other is in subcutaneous implantation style in the heads, known as “Subcutaneous Implantation TAG”. The study made comparison between these two kinds of RFIDs and the evaluated them to choose the better one.
In addition, the mix of RFID chips for the production of information systems, namely, “The livestock management system” is also indispensable. The research also investigated in the management system , concepts of design, and related systems topics. Finally, the results are hoped to make contribution to the introduction of technology to agro-biography.
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