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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.
271

Systemic communication and performance : a humanist learning approach to agricultural extension and rural development /

Khatoonabadi, Ahmad. January 1994 (has links)
Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury,1994. Thesis (Ph.D.) -- University of Western Sydney, Nepean,1994. / A thesis submitted to the School of Agriculture and Rural Development, University of Western Sydney, Hawkesbury, and The Faculty of Visual and Performing Arts, University of Western Sydney Nepean, in part fulfilment of the requirements for the Degree of Doctor of Philosophy. Includes bibliography - leaves 310 - 328 and appendices.
272

Geographical information system for integrated management of agriculture and the environment

Smit, Christian 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The agricultural sector plays a valuable role in the South African economy. However, agriculture is embedded in the natural environment. The research problem revolves around the lack of an information management system, capable of integrated agricultural and environmental management to promote sustainable agricultural development on farm level. This study aimed to develop a spatial information management system to aid with integrated agricultural and environmental management. The study area consisted of a seven-farm production unit, Howbill Properties, which provided the necessary agricultural and environmental elements for this study. Spatial data requirements were identified by unpacking the relevant imperatives directing integrated agricultural and environmental management. Data was collected with a recreational outdoor GPS device, digitised from remotely sensed images and obtained from various sources. Spatial data consisted of infrastructure data, such as water pumps, power lines, and fruit orchard boundaries, whereas environmental spatial data consisted of natural resource data, and topographic data. The study further details the process of selecting the necessary components for an enterprise GIS and building the system. PostgreSQL with the PostGIS spatial extension was selected as the spatial database and QGIS was selected as the desktop GIS application. It was found that the prototype integrated spatial information system could be effectively applied to assist integrated agricultural and environmental management. The prototype spatial information system was able to serve the needs of novice to advanced users. However, insufficient spatial data were identified as a limitation, and spatial data should be improved and updated regularly. / AFRIKAANSE OPSOMMING: Landbou speel „n belangrikke rol in die Suid-Afrikaanse ekonomie. Landbou is egter vervat in die natuurlike omgewing. Die probleem wentel om die gebrek aan 'n geografiese inligtingstelsel wat in staat is om geïntegreerde landbou- en omgewingsbestuur op plaasvlak te bevorder. Hierdie studie het ten doel gehad om 'n ruimtelike inligtingsbestuurstelsel te ontwikkel om die voorafgaande probleem aan te spreek. Die studie area bestaan uit 'n sewe-plaas produksie-eenheid, Howbill Properties, wat die nodige landbou- en omgewingselemente vir hierdie studie bevat het. Ruimtelike datavereistes is geïdentifiseer deur die relevante internasionale, nasionale, provinsiale, en mark vereistes wat geïntegreerde landbou en omgewingsbestuur rig, te ondersoek. Data is ingesamel met 'n behulp van „n GPS-toestel, gedigitaliseer van afstandswaarnemingsdata en ingesamel van verskeie bronne. Ruimtelike data het bestaan uit infrastruktuur data, soos water pompe, kraglyne, en vrugte boord grense, terwyl die ruimtelike omgewing data bestaan het uit natuurlike hulpbron data en topografiese data. Verder behandel die studie die proses van hoe die nodige komponente vir 'n ondernemings GIS gekies was en hoe die stelsel ontwikkel was. PostgreSQL met die PostGIS ruimtelike uitbreiding is gekies as die ruimtelike databasis en QGIS is gekies as die GIS program. Daar is gevind dat die prototipe geïntegreerde ruimtelike inligtingstelsel doeltreffend toegepas kan word vir geïntegreerde landbou en omgewingsbestuur. Die prototipe ruimtelike inligtingstelsel was in staat om aan die behoeftes van „n beginner gebruiker sowel as gevorderde gebruikers te voorsien. Daar was ook bevind dat onvoldoende ruimtelike data die stelsel beperk, en dat data sal voordurend verbeter en opgedateer moet word.
273

Entre resistências e inserções : a construção da agroecologia na Embrapa

Camargo, Vanessa Ortiz de 28 August 2009 (has links)
Made available in DSpace on 2016-06-02T20:39:11Z (GMT). No. of bitstreams: 1 2645.pdf: 637881 bytes, checksum: 4aec1fbbf1c340b1dfb6372e58408184 (MD5) Previous issue date: 2009-08-28 / Financiadora de Estudos e Projetos / The goal of this dissertation is to investigate as agroecology, alternative approach to agriculture characterized by socio-environmental concerns, becomes a prospect that internalises in public institutions of research devoted to agriculture. Analyzing the case of Empresa Brasileira de Pesquisa Agropecuaria (Embrapa), which was historically linked to agricultural modernization in Brazil, the research aims to investigate what the conditions of insertion of the agroecology theme is how the process of legitimation of this. The research consisted of a case study on the institutional process of legitimization of agroecology in EMBRAPA. First, we analyze the official discourse of the company, the institutional position, defined in documents published on the subject. A second step of analysis aims to evaluate how this process is reflected in the level of daily practices of agents. For this, interviews were conducted with experts and researchers from Embrapa Meio Ambiente, located in Jaguariúna- SP. Understanding the Embrapa Meio Ambiente as a field of provisions in dispute, where the agents compete for the accumulation of specific, we show that the environmental issue, and particularly the discussion agroecology, introduce new elements and provide conflicting dynamics. The agroecological perspective takes a marginal seat, or dominated the field in relation to conventional farming, and thus the defenders of agroecology looking agents make use of various strategies, seeking state their views and their understanding of science. If on the one hand social movements seeking intervention in the company entering new perspectives on the other hand, the institution makes use of a series of devices to accommodate new practices to their routines. / O objetivo desta dissertação consiste em investigar como a agroecologia, abordagem alternativa de agricultura caracterizada por preocupações sócio-ambientais, passa a ser uma perspectiva que se internaliza em instituições públicas de pesquisa voltadas ao setor agropecuário. Analisando o caso da Empresa Brasileira de Pesquisa Agropecuária (Embrapa), que historicamente esteve vinculada à modernização agrícola no Brasil, a pesquisa pretende investigar quais as condições da inserção da temática da agroecologia e como se dá o processo de legitimação desta perspectiva. A pesquisa consistiu em um estudo de caso sobre o processo de legitimação institucional da agroecologia na EMBRAPA. Num primeiro momento, analisamos o discurso oficial da empresa, a posição institucional, definida nos documentos publicados, relativa ao tema. Um segundo passo da análise buscou verificar como esse processo se traduz no nível das práticas cotidianas dos agentes. Para tanto, foram realizadas entrevistas com técnicos e pesquisadores da unidade descentralizada Embrapa Meio Ambiente, localizada em Jaguariúna-SP. Entendendo a Embrapa Meio Ambiente como um campo de disposições em disputa, onde os agentes concorrem para a acumulação de capital específico, mostramos que a temática ambiental e, em especial, o debate agroecológico, introduzem elementos novos e estabelecem dinâmicas conflitivas. A perspectiva agroecológica toma um lugar marginal, ou dominado no campo, em relação à agricultura convencional e, assim, os agentes defensores da agroecologia procuram lançar mão de diversas estratégias, buscando afirmar seu ponto de vista e seu entendimento de ciência. Se por um lado os movimentos sociais buscam intervir na empresa inserindo novas perspectivas, por outro, a instituição lança mão de uma série de dispositivos para acomodar novas práticas às suas rotinas.
274

Permaculture as an aspect of environmental learning: an investigation into secondary school communities in Zimbabwe

Nyika, Mugove Walter January 2002 (has links)
The Schools and Colleges Permaculture (SCOPE) Programme in Zimbabwe has developed a process for use by schools in planning for the sustainable management of their land. The process is called Integrated Land-Use Design (ILUD) and is based on Permaculture principles. The ILUD process has so far been implemented in 54 pilot schools where it has been used to facilitate the re-design of the school grounds through the active participation of the students, staff and parents. The aim of this research was to investigate what environmental learning takes place during the implementation of the ILUD process and related activities, with a view to informing the improvement of the process. The research was conducted within the interpretive paradigm with particular use being made of the Symbolic Interactionist theoretical framework to explore the social situations in which the ILUD process has been applied. A purposive sample of two schools and five form 4 (grade 11) pupils from each school was selected for the study. The main data collection method was the structured interview. Other data were collected from nonparticipant observations and the analysis of documents, particularly photographs. The data was analysed using the constant comparative method. The findings point towards a significant contribution from the Permaculture activities to the environmental knowledge, environmental management skills and the positive environmental attitudes of the pupils. The work done at the two schools indicates the usefulness of the ILUD process as a tool for environmental action in the schools but its application in the communities was found to be limited by constraints such as lack of resources and the limited capacity of teachers to work in the field of adult education and training. It is recommended that Permaculture should be integrated into the secondary school curriculum if the momentum of the progress made so far is to be maintained. The SCOPE Programme itself needs to be strengthened for its work with communities. There is, for example, a need for adult education and training methods if the introduction of ILUD to the communities is to be successful.
275

Sistema de irrigação de baixa pressão e baixo custo para culturas em fileiras e adensadas

Xavier, Alyssandny Francisco Matos 28 July 2016 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-01-31T20:46:57Z No. of bitstreams: 1 AlyssandnyFMX_DISSERT.pdf: 1896016 bytes, checksum: 1029c37a590c0861713067752d4df5e4 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T14:53:04Z (GMT) No. of bitstreams: 1 AlyssandnyFMX_DISSERT.pdf: 1896016 bytes, checksum: 1029c37a590c0861713067752d4df5e4 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T14:53:18Z (GMT) No. of bitstreams: 1 AlyssandnyFMX_DISSERT.pdf: 1896016 bytes, checksum: 1029c37a590c0861713067752d4df5e4 (MD5) / Made available in DSpace on 2017-03-21T15:06:48Z (GMT). No. of bitstreams: 1 AlyssandnyFMX_DISSERT.pdf: 1896016 bytes, checksum: 1029c37a590c0861713067752d4df5e4 (MD5) Previous issue date: 2016-07-28 / The semi-arid to present unfavorable weather conditions for agriculture, with water deficit during most time of the year, poorly distributed rainfall and high temperatures, require irrigation for crop development. In the perspective of sustainable agriculture, drip irrigation is the method of more efficient use of water, which has attracted farmers and agricultural companies. Irrigation systems by gravity in closed conduits are the most suitable for family farmers, due to low cost and operate at low pressures. This study aimed to develop a similar irrigation system to the bubbler which will enable water form located in crop plants in rows and dense. Flow-diameter-length-hydraulic load curves were established. A sizing model was fitted to the irrigation system where feed tests were carried out in the field in different soil, to establish a model that relates flow rate, length of the irrigation bowl-time and eventually the installation of the irrigation system which evaluated the uniformity of flow in the area. The installation of the irrigation system was carried out in the municipality of Upanema / RN, in a Cambisol medium texture, cultivated with forage cactus using water supply Regarding the water breakthrough curves test soil, it can be said that the potential equations were similar logarithmic equations. It is recommended the use of potential model to represent the data of the water feed test on the ground curve. The prototype of the load losses virtually showed no change and were minimal, since the installed project this was very significant and with some variations. The project installed presented distribution uniformity coefficients (CUD) and statistical uniformity coefficient (CUE) with values ranging from good to excellent / O semiárido por apresentar condições climáticas desfavoráveis para agricultura, com déficit hídrico durante grande época do ano, chuvas mal distribuídas e altas temperaturas, necessita da irrigação para o desenvolvimento das culturas. Na ótica da agricultura sustentável, a irrigação localizada é o método de maior eficiência no uso da água, o que tem atraído os produtores rurais e as empresas agrícolas. Os sistemas de irrigação por gravidade em condutos fechados são os mais indicados para os produtores familiares, devido baixo custo e por operarem a baixas pressões. O presente trabalho teve como objetivo desenvolver um sistema de irrigação similar ao bubbler que permita aplicar água de forma localizada em plantas de cultivos em linhas e adensadas. Foram estabelecidas curvas de vazão-comprimento-carga hidráulica. Foi montado um modelo de dimensionamento para o sistema de irrigação, onde foram realizados testes de avanço em campo em diferentes solos, para estabelecer um modelo que relacione vazão-comprimento da bacia-tempo de irrigação e, por fim, a instalação do sistema de irrigação onde se avaliou a uniformidade da vazão na área. A instalação do sistema de irrigação foi realizada no município de Upanema/RN, em um Cambissolo de textura média, cultivado com palma forrageira, utilizando água de abastecimento. Em relação às curvas do teste de avanço da água no solo, pode-se dizer que as equações potenciais foram similares as equações logarítmicas. Recomenda-se o uso do modelo potencial para representar os dados da curva do teste de avanço de água no solo. As perdas de carga do protótipo praticamente não apresentaram variação e foram mínimas, já no projeto instalado este foi bastante expressivo e com algumas variações. O projeto instalado apresentou coeficientes de uniformidade de distribuição (CUD) e coeficientes de uniformidade estatístico (CUE) com valores variando de bom a excelente / 2017-01-31
276

Viabilidade econômica e sanitária do cultivo da alface em sistema hidropônico com diferentes tipos de água.

ARAÚJO, Ariosto Céleo de. 10 October 2018 (has links)
Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-10T13:18:10Z No. of bitstreams: 1 ARIOSTO CÉLEO DE ARAÚJO - DISSERTAÇÃO (PPGRN) 2017.pdf: 1741406 bytes, checksum: c5b7496be1aa18f048d9de4601d35aed (MD5) / Made available in DSpace on 2018-10-10T13:18:10Z (GMT). No. of bitstreams: 1 ARIOSTO CÉLEO DE ARAÚJO - DISSERTAÇÃO (PPGRN) 2017.pdf: 1741406 bytes, checksum: c5b7496be1aa18f048d9de4601d35aed (MD5) Previous issue date: 2017-03-31 / Capes / Atualmente, uma das grandes preocupações refere-se à qualidade das águas superficiais, que vêm sendo utilizadas como suporte para a eliminação dos resíduos produzidos pelo homem. Objetivou-se avaliar o uso de águas residuais e salinas na produção de variedades da alface (Lactuca sativa L.) em sistema hidropônico no CCT/UEPB de Lagoa Seca – PB, visando contribuir com a viabilidade de sua aplicação na agricultura familiar regional. O experimento foi conduzido em sistema hidropônico adotando-se a técnica do fluxo laminar de nutrientes (NFT). O delineamento experimental adotado foi o de blocos casualizados com os tratamentos dispostos em parcelas subdivididas em esquema fatorial 7x3, com três repetições, cujos fatores foram 7 soluções hidropônicas e três cultivares de alface. As soluções nutritivas otimizadas foram formuladas tomando-se como referência a solução nutritiva de Furlani. A parcela experimental foi constituída pelas soluções nutritivas (S): S1 = solução de Furlani; S2 = água residuária doméstica; S3 = água residuária doméstica otimizada; S4 = água salobra de poço tubular para captação de água subterrânea; S5 = água salobra de poço tubular para captação de água subterrânea otimizada; S6 = solução água residuária provenientes do reator UASB e S7 = solução água residuária provenientes do reator UASB otimizada). Os resultados desta pesquisa evidenciaram a viabilidade (econômica, social e ambiental) na utilização de efluentes e águas salobras no cultivo hidropônico, propiciando hortaliças com níveis sanitários adequados ao consumo. Porém, mediante o apoio governamental ao crédito e auxílio de assistência técnica a fim de promover o conhecimento técnico, bem como a educação ambiental que propiciem um correto manejo agrícola. A utilização das soluções sugeridas nessa pesquisa (S5, S6 e S7) reduzem o impacto negativo ao ambiente ao se evitar seu lançamento em corpos d'água, como também permite uma economia quanto ao uso de fertilizantes na agricultura e consequentemente aumenta a viabilidade econômica do produto.Todos os tratamentos atenderam ao padrão estabelecido pela RDC nº 12 de 02/01/2001 da ANVISA, que foram ausentes para coliformes termotolerantes e possuindo níveis toleráveis de coliformes totais. / Currently, one of the major concerns is the quality of surface water, which has been used as a support for the disposal of waste produced by man. The objective of this study was to evaluate the use of residual and salt water in the production of lettuce (Lactuca sativa L.) varieties in a hydroponic system at the CCT / UEPB of Lagoa Seca - PB, aiming to contribute to the viability of its application in regional family agriculture. The experiment was conducted in a hydroponic system using the laminar nutrient flow technique (NFT). The experimental design was randomized blocks with the treatments arranged in split plots subdivided in a 7x3 factorial scheme, with three replications, whose factors were 7 hydroponic solutions and three lettuce cultivars. Optimized nutrient solutions were formulated by reference to Furlani's nutrient solution. The experimental portion consisted of the nutritive solutions (S): S1 = solution of Furlani; S2 = domestic wastewater; S3 = optimized domestic wastewater; S4 = brackish water from tubular wells to collect groundwater; S5 = brackish tubular well water for optimal groundwater abstraction; S6 = wastewater solution from the UASB reactor and S7 = wastewater solution from the optimized UASB reactor). The results of this research evidenced the viability (economic, social and environmental) in the use of effluents and brackish water in hydroponic cultivation, providing vegetables with sanitary levels adequate to consumption. However, through government support for credit and technical assistance assistance in order to promote technical knowledge and environmental education that provide a correct agricultural management. The use of the solutions suggested in this research (S5, S6 and S7) reduces the negative impact on the environment by avoiding its introduction into water bodies, as well as saving on the use of fertilizers in agriculture and, consequently, increasing the economic viability of All treatments met the standard established by RDC No. 12 of January 2, 2001 of ANVISA, which were absent for thermotolerant coliforms and having tolerable levels of total coliforms.
277

Velhos conhecimentos, novos desenvolvimentos : transições no regime sociotécnico da agricultura : a produção de novidades entre agricultores produtores de plantas medicinais no sul do Brasil

Marques, Flávia Charão January 2009 (has links)
A noção de que o desenvolvimento é um processo relacionado a um progresso técnico positivo e linear contribuiu para gerar um cenário social e ambiental insustentável e, aparentemente, tem conduzido a sociedade contemporânea para uma homogeneização cultural e material. Ao contrário, observando amiúde os espaços rurais, se identifica que há a emergência de dinâmicas sócio-espaciais heterogêneas e multifuncionais. Neste contexto, a agricultura exerce papel fundamental como atividade relevante na construção de desenvolvimentos rurais sustentáveis. No entanto, o modelo de modernização agrícola, orientado pelo regime sociotécnico dominante, não responde a este imperativo, tornando fundamental identificar possibilidades de transições para tal regime, de modo a permitir à agricultura a retomada de seu sentido como 'co-produção'. A partir de uma abordagem multinível, multi-ator e multi-aspecto, construída com elementos da Perspectiva Multinível e da Perspectiva Orientada pelo Ator, este trabalho de tese objetivou explorar a potencialidade da 'produção de novidades' para a promoção de transições no regime sociotécnico dominante na agricultura, através da análise de novidades desenvolvidas por agricultores na produção ecológica de plantas medicinais no Sul do Brasil. O estudo qualitativo de cinco casos de famílias de agricultores, que produzem plantas medicinais sob sistema ecológico, mostrou intensa produção de novidades e potencialidade para o estabelecimento de um nicho de inovação, considerando que há ativos processos de articulação de aprendizagens e de estabelecimento de redes sociais. A maior vulnerabilidade na emergência do nicho é a falta de alinhamento de expectativas entre distintos atores envolvidos, que está relacionada à dificuldade em superar barreiras sustentadas pelo regime prevalente. Considerando o nicho como lócus privilegiado para a inovação, essa superação parece depender de uma 'gestão da transição', que pode ser entendida como a criação de condições sócio-institucionais que favoreçam a construção de novas institucionalidades, identidades e compromissos sociais. / The notion that development is a process related to a positive and linear technical progress has generated an unsustainable social and environmental scenario and apparently led to a cultural and material homogenization of society. Rather, closely observing rural spaces, we can identify emergences of heterogeneous socio-spatial and multifunctional dynamics. In this context, agriculture plays an active role in the construction of sustainable rural developments. However, the agricultural modernization patterns, oriented by the dominant sociotechnical regime, is not responding this claim, thus proposing transitions to such regime is fundamental to recover agriculture meaning as 'co-production'. Since a multilevel, multiactor and multi-aspect framework, built taking elements from Multilevel Perspective and Actor Oriented Approach, this thesis aimed to explore the potential of 'novelty production' for promoting transitions in dominant agriculture sociotechnical regime, through the analysis of novelties developed by farmers in medicinal plants ecological production in southern Brazil. Qualitative studies of five cases of farmers' families who produce medicinal plants under ecological system showed an impressive novelty production and potentialities in establishing a niche of innovation, considering that there are active processes of learning articulation and social networks building. The main vulnerability in the niche emergence is the absence of expectations alignment between different enrolled actors, which is related to the difficulty in overcoming prevalent regime. Taking into account that the niche is the core for innovation, this overcoming seems to depend on 'transition management', which can be understood as the creation of enabling social and institutional conditions for construction of new institutionalities, identities and social commitments.
278

The effect of nutritional Nucleotides and parenteral Glucocorticoids on improving immunoglobulin absorption and growth by neonate calves : reducing the carbon footprint of dairy calves

Schoombee, Wilhelm Sternberg 03 1900 (has links)
Antibiotics are routinely used in modern livestock production systems to treat and prevent disease as well as to enhance livestock production and/or outputs. This widespread use of antibiotics has led to a growing worldwide interest in antibioticfree animal production. The addition of feed supplements such as nucleotides to improve intestinal health as well as the early development of the immune system needs to be investigated as an environmentally-friendly nutritional management activity. In this study four (4) groups of newborn Holstein calves (n=24) were evaluated after being treated as follows: Group 1 (Negative control), Group 2 (Investigational Veterinary Product (IVP) 1 – Oral supplement containing nucleotides, vitamins, essential fatty acids, essential amino acids, pre-biotics and trace-minerals), Group 3 (IVP 2 – Oral supplement containing nucleotides only at concentration and dosage equal to IVP1) and Group 4 (IVP 3 - Parenteral glucocorticoids). Results of the study indicated that: Pre-colostral Serum IgG titres – After titration of the serum the anti-BVDV results showed no difference between the study groups. All calves recorded a SP ratio of zero value (0.00 ± 0.2) indicating that they had not been nursed by their mothers prior to the start of the study. This was an entrance requirement for the calves to be enrolled into the study. Apparent Efficiency of Absorption % (AEA%) – Literature shows that an AEA% result of between 20%-30% is good and 35% is excellent. The AEA% recorded for this study fell within this range although there was no statistically significant difference shown between the groups. In spite of a strictly controlled study protocol, 7 of the 24 calves (29%) still suffered from FPT in this study. The result falls within the range of 19% - 37% reported on United States of America (USA) farms by Doepel and Bartier in 2014. Serum cortisol - When compared to the control group, there were no statistical significant difference evident for group 2 and group 3. However, the difference between the Glucocorticoid – Group 4 and the control and other groups was statistically significant (P = 0.0001; table 12) at the various time intervals. It was also evident that the inclusion of parenteral glucocorticoids (group 4) may have assisted in prolonging the natural “gut closure”. Gut closure – a positive 2 point linear regression forecast line indicated an increasing trend in IgG absorption post-24 hours for group number 4 whilst groups 1, 2 and 3 each had a negative 2 point linear regression forecast line (figure 23). Weight / ADG (D42) - Group 2 showed a statistically significant increase in mean D42 weight (P = 0.0042) of 59.167 kg ± 3.545 kg when compared to the other study groups and compared to the control group (P = 0.0227). A comparison of the relative increase in mass of groups indicated that Group 2 efficiently achieved this result with a statistically significant ADG of 0.536 kg (P = 0.014) compared to the other study groups and compared to the control group (P = 0.022). In addition, weight / FCR – FCR was calculated for all groups as follows: G1 – 4.000 kg, G2 - 2.593 kg, G3 – 2.703 kg and G4 - 3.012 kg feed required for the production of 1 kg meat. The results indicated that the group 2 feed input was the most economical followed by groups 3, 4 and control respectively. In conclusion, it is evident that a nutritional supplement containing nucleotides, vitamins, trace- minerals, essential fatty acids, essential amino acids and pre-biotics may contribute significantly to important economic indicators such as weight gain, ADG and FCR on a commercial dairy farm. / Environmental Sciences / Ph. D. (Environmental Science)
279

Os sistemas agroflorestais à base de cacau e mogno como alternativa sustentável de cobertura vegetal para recuperação de áreas degradadas pelo desmatamento na Amazônia brasileira

Reis, Sylvan Martins dos January 2015 (has links)
O desmatamento da floresta amazônica tem causado preocupação na sociedade civil e científica mundial demandando pesquisas que busquem mitigar os impactos ambientais provocados por esse fenômeno. Esta tese tem como objetivo central analisar o uso dos sistemas agroflorestais à base de cacau como alternativa para recuperação de áreas degradadas pelo desmatamento da floresta Amazônica brasileira. Portanto, são aprestados três trabalhos que abordam essa temática. O primeiro estudo realiza uma pesquisa documental da produção científica na Amazônia brasileira sobre os sistemas agroflorestais com cacau (Theobroma cacao L.) buscando identificar os principais escopos nos quais essas pesquisas estão inseridas, assim como, subsidiar a prospecção de escopos complementares para futuras pesquisas. O segundo estudo analisa a utilização de sistemas agroflorestais à base de cacau como alternativa de cobertura vegetal sustentável para recuperação das áreas degradadas na Amazônia brasileira, assim como, compara os rendimentos de dois sistemas agroflorestais, um indicado pela pesquisa agropecuária e outro alternativo, implantado em área de produtor rural. Finalmente, o terceiro estudo analisa o crescimento e rendimento de madeira das plantas de mogno (Swietenia macrophylla King) utilizadas como sombreamento definitivo em sistemas agroflorestais à base de cacau implantadas em uma propriedade rural localizada no Estado do Pará, na Amazônia brasileira, em solos do tipo Terra Rocha Estruturada e Podzólico Vermelho Amarelo. Os resultados mostram que mais de 47 espécies vegetais de valor comercial nativas da região ou exóticas são contempladas nos diferentes sistemas agroflorestais à base de cacau cultivados na região. Os indicadores de rentabilidade obtidos dos dois sistemas analisados indicam que esses sistemas são viáveis financeiramente e podem ser financiados pelo programa oficial de crédito rural destinado a implantação de sistemas agroflorestais na Amazônia, o FNO-Biodiversidade, assim como, que as quantidades de carbono atmosférico sequestrada por esses sistemas se aproximam as das florestas nativas. E finalmente, que as plantas de mogno utilizadas como sombreamento nesses sistemas tiveram bom desenvolvimento em altura e diâmetro e o rendimento de madeira foi superior ao encontrado em condições naturais nas florestas da região. Esses resultados sugerem que os sistemas agroflorestais à base de cacau são uma alternativa econômica e ecologicamente sustentáveis para recompor a cobertura vegetal das áreas degradadas pelo desmatamento na Amazônia brasileira, além de proporcionar a mitigação dos danos ambientais provocados pelo desmatamento. / The deforestation of the Amazon rainforest has caused concern in civil society and global scientific research in fact demanding mitigate environmental impacts caused by this phenomenon. This thesis aims to analyze use of central agroforestry to cocoa as an alternative for recovery of degraded areas by deforestation of the Amazon rainforest in Brazil. So are three works that discuss this dressed. The first study performs a documentary research of the scientific production in the Brazilian Amazon on agroforestry systems with Cacao (Theobroma cacao l.) seeking to identify the main scopes in which these searches are included, as well as subsidizing the prospect for additional scopes for further research. The second study examines the use of agroforestry systems based on cocoa as an alternative sustainable vegetation cover for recovery of degraded areas in the Brazilian Amazon, as well as, compares the income of two agroforestry systems, an agricultural research and indicated another alternative, deployed in the area of rural producer. Finally, the third study examines the growth and yield of wood plants of mahogany (Swietenia macrophylla King) used as final shading in agroforestry cocoa base deployed in a country estate in the Pará State, in the Brazilian Amazon, in soils of the Earth type Structured Rock and Red Yellow Podzolic. The results show that over 47 species of plants native to the region or business value are considered exotic in different agroforestry systems based on cacao grown in the region. The profitability indicators obtained from two systems analyzed indicate that these systems are financially viable and can be financed by the program officer rural credit aimed at implementation of agroforestry systems in the Amazon, the FNO-biodiversity, as well as the amounts of atmospheric carbon sequestered by these systems approach the native forests. And finally, the plants of mahogany used as shading on these systems have had good development in height and diameter, and yield of wood was superior to that found in natural conditions in the forests of the region. These results suggest that the cocoa-based agroforestry systems are an economically and ecologically sustainable alternative to recompose the vegetal covering of areas degraded by deforestation in the Brazilian Amazon, in addition to providing the mitigation of environmental damage caused by deforestation.
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Velhos conhecimentos, novos desenvolvimentos : transições no regime sociotécnico da agricultura : a produção de novidades entre agricultores produtores de plantas medicinais no sul do Brasil

Marques, Flávia Charão January 2009 (has links)
A noção de que o desenvolvimento é um processo relacionado a um progresso técnico positivo e linear contribuiu para gerar um cenário social e ambiental insustentável e, aparentemente, tem conduzido a sociedade contemporânea para uma homogeneização cultural e material. Ao contrário, observando amiúde os espaços rurais, se identifica que há a emergência de dinâmicas sócio-espaciais heterogêneas e multifuncionais. Neste contexto, a agricultura exerce papel fundamental como atividade relevante na construção de desenvolvimentos rurais sustentáveis. No entanto, o modelo de modernização agrícola, orientado pelo regime sociotécnico dominante, não responde a este imperativo, tornando fundamental identificar possibilidades de transições para tal regime, de modo a permitir à agricultura a retomada de seu sentido como 'co-produção'. A partir de uma abordagem multinível, multi-ator e multi-aspecto, construída com elementos da Perspectiva Multinível e da Perspectiva Orientada pelo Ator, este trabalho de tese objetivou explorar a potencialidade da 'produção de novidades' para a promoção de transições no regime sociotécnico dominante na agricultura, através da análise de novidades desenvolvidas por agricultores na produção ecológica de plantas medicinais no Sul do Brasil. O estudo qualitativo de cinco casos de famílias de agricultores, que produzem plantas medicinais sob sistema ecológico, mostrou intensa produção de novidades e potencialidade para o estabelecimento de um nicho de inovação, considerando que há ativos processos de articulação de aprendizagens e de estabelecimento de redes sociais. A maior vulnerabilidade na emergência do nicho é a falta de alinhamento de expectativas entre distintos atores envolvidos, que está relacionada à dificuldade em superar barreiras sustentadas pelo regime prevalente. Considerando o nicho como lócus privilegiado para a inovação, essa superação parece depender de uma 'gestão da transição', que pode ser entendida como a criação de condições sócio-institucionais que favoreçam a construção de novas institucionalidades, identidades e compromissos sociais. / The notion that development is a process related to a positive and linear technical progress has generated an unsustainable social and environmental scenario and apparently led to a cultural and material homogenization of society. Rather, closely observing rural spaces, we can identify emergences of heterogeneous socio-spatial and multifunctional dynamics. In this context, agriculture plays an active role in the construction of sustainable rural developments. However, the agricultural modernization patterns, oriented by the dominant sociotechnical regime, is not responding this claim, thus proposing transitions to such regime is fundamental to recover agriculture meaning as 'co-production'. Since a multilevel, multiactor and multi-aspect framework, built taking elements from Multilevel Perspective and Actor Oriented Approach, this thesis aimed to explore the potential of 'novelty production' for promoting transitions in dominant agriculture sociotechnical regime, through the analysis of novelties developed by farmers in medicinal plants ecological production in southern Brazil. Qualitative studies of five cases of farmers' families who produce medicinal plants under ecological system showed an impressive novelty production and potentialities in establishing a niche of innovation, considering that there are active processes of learning articulation and social networks building. The main vulnerability in the niche emergence is the absence of expectations alignment between different enrolled actors, which is related to the difficulty in overcoming prevalent regime. Taking into account that the niche is the core for innovation, this overcoming seems to depend on 'transition management', which can be understood as the creation of enabling social and institutional conditions for construction of new institutionalities, identities and social commitments.

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