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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.
1

Fertilizantes de leguminosas: tecnologia inovadora de aduba??o verde para provis?o de nitrog?nio em sistemas org?nicos de produ??o. / Legume fertilizers: innovative technology of green manuring for nitrogen supply in organic farming systems.

Almeida, Maxwell Mer?on Tezolin Barros 16 March 2007 (has links)
Made available in DSpace on 2016-04-28T14:58:33Z (GMT). No. of bitstreams: 1 2007- Maxwell Mercon Tezolin Barros Almeida.pdf: 1302858 bytes, checksum: 1bdf7888e20d418ce73170bea64d112e (MD5) Previous issue date: 2007-03-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / One of the main limitations to the organic food production is the reduced availability of low cost and efficient nitrogen (N) sources. Green manuring practices, in rotation or intercropped, have been used, but hardly are they able to supply crop needs. This dissertation presents an innovative technology of green manuring, derived of the cutting, dehydration and milling of the aerial biomass of some plants from Leguminosae family (with high potential of biological N2 fixation, N accumulation and handling easiness), with posterior storage and use of the produced material, called legume fertilizer. The technology allows the green manure storage, the production systematization and its use in more appropriate amounts and times, favoring the synchronization/efficiency of N provision. The objects of this study were: the development and evaluation of different production forms of legume fertilizers three herbaceous species: velvet bean (Mucuna pruriens), sunn hemp (Crotalaria juncea) and arachis (Arachis pintoi), and two species of tree: gliricidia (Gliricidia sepium) and leucaena (Leucaena leucocephala) ; the physical and chemical characterization of these materials, the utilization potential as alternative sources of N for organic farming systems, their influence on the shelf life of lettuce (Lactuca sativa cv. Vera), on chemical and biological soil attributes and on germination and establishment of arugula (Eruca sativa cv. Cultivada) seedlings. Three experiments have been conducted: one in field with lettuce, and two in green house with arugula. Legume fertilizers were compared at N basis with poultry bed manure from meat industry. The gliricidia fertilizer showed better physical and chemical attributes (lower C/N and lignin/N ratios) implying higher potential for biodisponibilization of N. This potential was corroborated for two experiments, in which the concentration and accumulation of N in the aerial part of lettuce and arugula was significantly superior to the other organic sources of N (velvet bean fertilizer and poultry bed manure). However, in the other experiment of arugula, the efficiency of five legume fertilizers and poultry bed manure were similar. The incorporation and the reduction of the applied doses of N had increased the efficiency of the provision of N for arugula. Antagonistic effect had been only observed on the germination and establishment of arugula seedlings when the legume fertilizers had been incorporated in the soil, but not when applied in surface. Lettuce shelf life was not affected by application of these organic sources of used N. The legume fertilizers and the poultry bed manure had favored the accumulation of C and total N, and the soil microbial activity with similar magnitudes. This dissertation indicates that legume fertilizers are promising sources of N for the organic farming systems, capable to replace the factory poultry bed manure at the same N level. This potential assumes relevance since poultry bed manure, one of the most used and efficient sources of organic of N, has some restrictions for its use in organic agriculture. / Um dos principais entraves ? produ??o org?nica de alimentos ? a reduzida disponibilidade de fontes de nitrog?nio (N) eficientes e de baixo custo. Pr?ticas de aduba??o verde, em rota??o ou cons?rcio, t?m sido utilizadas, mas dificilmente conseguem garantir as exig?ncias das culturas. Esta disserta??o apresenta uma tecnologia inovadora de aduba??o verde, derivada do corte, desidrata??o e moagem da biomassa a?rea de determinadas plantas da fam?lia Leguminosae (com elevado potencial de fixa??o biol?gica de N2, ac?mulo de N e facilidade de manejo), com posterior armazenagem e uso do material produzido, denominado fertilizante de leguminosa. A tecnologia permite a estocagem do adubo verde, a sistematiza??o da produ??o e seu uso em quantidades e ?pocas mais adequadas, favorecendo a sincronia/efici?ncia da provis?o de N. Foram objetos deste estudo: o desenvolvimento e a avalia??o de diferentes formas de produ??o de fertilizantes de leguminosas tr?s de esp?cies herb?ceas: mucuna cinza (Mucuna pruriens), crotal?ria (Crotalaria juncea) e arachis (Arachis pintoi), e dois de esp?cies arb?reas: gliric?dia (Gliricidia sepium) e leucena (Leucaena leucocephala) ; a caracteriza??o f?sica e qu?mica desses materiais, o potencial de uso como fontes alternativas de N para sistemas org?nicos de produ??o, a influ?ncia das aduba??es sobre a vida ?til p?s-colheita de alface (Lactuca sativa cv. Vera), sobre atributos qu?micos e biol?gicos do solo e sobre a germina??o e estabelecimento de pl?ntulas de r?cula (Eruca sativa cv. Cultivada). Tr?s experimentos foram conduzidos: um em campo com a cultura da alface, e dois em vasos com r?cula. Em todos eles, as aduba??es com os fertilizantes de leguminosas foram comparadas com cama de avi?rio industrial, proveniente de galp?o de frangos para abate, assegurando-se doses equivalentes de N-total. O fertilizante de gliric?dia foi o que apresentou maior potencial f?sico e qu?mico para biodisponibiliza??o de N (rela??es C/N e lignina/N, baixas). Esse potencial foi corroborado por dois experimentos, nos quais a concentra??o e ac?mulo de N na parte a?rea de alface e r?cula foram significativamente superiores aos proporcionados pelas demais fontes org?nicas de N (fertilizante de mucuna cinza e cama de avi?rio). No entanto, no outro experimento de r?cula, a efici?ncia dos cinco fertilizantes de leguminosas e da cama de avi?rio foi semelhante. A incorpora??o e a diminui??o das doses de N aplicadas aumentaram a efici?ncia da provis?o de N para a r?cula. Efeitos antag?nicos, s? foram observados sobre a germina??o e estabelecimento das pl?ntulas de r?cula quando os fertilizantes de leguminosas foram incorporados ao solo, mas n?o quando aplicados em cobertura. A vida ?til p?s-colheita das alfaces n?o foi influenciada quanto ? fonte org?nica de N utilizada. Os fertilizantes de leguminosas e a cama de avi?rio favoreceram ao ac?mulo de C e N-total, e a atividade microbiana no solo com magnitudes semelhantes. Esta disserta??o indica que os fertilizantes de leguminosas s?o fontes promissoras de N para os sistemas org?nicos de produ??o, capazes de substituir a cama de avi?rio industrial, em dosagem equivalente de N-total. Esse potencial assume relev?ncia, tendo em vista que a cama de avi?rio, uma das fontes de org?nicas de N mais usadas e eficazes, sofre restri??es quanto ao seu emprego em agricultura org?nica.

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