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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

Sistema silvipastoril com Myracrodruon urundeuva Fr. All. como alternativa de sustentabilidade

Cambuim, José [UNESP] 25 February 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-25Bitstream added on 2014-06-13T18:39:35Z : No. of bitstreams: 1 cambuim_j_me_ilha.pdf: 669446 bytes, checksum: 57cc613e5fa7f02d5c637e7b557d9fa7 (MD5) / No agronegócio brasileiro, em especial na pecuária, a atenção dos pecuaristas com o conforto ambiental e o bem-estar animal cresce anualmente. Os olhares dos criadores estão voltados não apenas para a perfeição do produto final, mas também para todo o processo de produção e para novos mercados internacionais, incluindo o fornecimento de condições ideais para o desenvolvimento dos animais. A engorda dos animais depende de vários fatores, que interligam e são responsáveis pelo bom ou mau desempenho, esses fatores geralmente são pastagens bem manejadas, mineralizadas adequadas, boas aguadas e o sombreamento de pastagens. O sistema silvipastoril (spp.) apresenta como um conjunto de técnicas alternativas de uso da terra, que implicam na combinação simultânea ou sequencialmente no mesmo terreno da produção pecuária com espécies florestais. Os benefícios para o solo resultariam da melhoria, no médio ao longo prazo, na ciclagem de nutrientes, causada pela absorção desses elementos pelas raízes das árvores, e a deposição no solo superficial de parte desses nutrientes, pela decomposição de folhas, raízes, etc. Sem a intervenção das raízes das árvores atuando como “rede de retenção”, parte desses nutrientes seria perdida por lixiviação ou ficaria indefinidamente indisponível para uma monocultura anual. Dentre as espécies que vem sofrendo interferência antrópica e pode ser utilizada em sistemas silvipastoris encontra-se a aroeira Myracrodruon urundeuva Fr AL, como estratégia de conservação e sustentabilidade. Este estudo teve como objetivo avaliar: a quantidade de biomassa da Urochloa (sinonímia Brachiaria decumbens) no sistema, que pode suportar até 1,7 UA (unidade animal) no verão e 1,4 UA (unidade animal) no inverno, e o incremento médio anual em volume da aroeira, aos 5, 10, 15 20, 25 e 54 anos... / In agribusiness, especially in farming, farmers' attention to the environmental comfort and animal welfare grows annually. The looks of the creators are directed not only to the perfection of the final product, but also for the entire production process and new international markets, including providing ideal conditions for the development of animals. The fattening of animals depends on several factors, which interconnect and are responsible for good or bad performance; these factors are generally well managed pastures, mineralized adequate, good shade and watered pastures. The silvopastoral system (spp.) presented as a set of technical alternatives of land use, involving the combination simultaneously or sequentially in the same field of livestock production with forest species. The benefits to the soil resulted in improvement in the medium to long term, nutrient cycling, caused by the absorption of these elements by the roots of trees, the topsoil and the deposition of these nutrients, the decomposition of leaves, roots, etc.. Without the intervention of tree roots acting as net retention, these nutrients would be lost by leaching or indefinitely would be unavailable for an annual monoculture. Among the species that has suffered human interference and can be used in silvopastoral systems is aroeira M. urundeuva Fr Al, as a conservation and sustainability. This study aimed to assess: the amount of biomass Urochloa (synonymy Brachiaria decumbens) system, which can support up to 1.7 AU (animal unit) in summer and 1.4 AU (animal unit) in winter, and the average increase annual volume of mastic, at 5, 10, 15, 20, 25 and 54 years old, ideal for thinning and survival of populations of M. urundeuva Fr All. Economic indicators and compare this system with the implementation of a silvopastoral system today. That consisted... (Complete abstract click electronic access below)
2

Hållbar skolträdgård : Ett designförslag med skogsträdgården som förebild

Edlund, Karin F January 2021 (has links)
Growing is a creative activity in lower school subject matter. It is an outdoor activity that creates movement. Gardening activities give favorable effects for the social teamwork in studentgroups and cultivation is a way to increase students' awareness of our food production. This argument exists in earlier studies that it is significant when school staff have motivated reasons to create school gardens. Of course, school gardens have always created problems. To get enough resources for management and lesson planning and to handle summer supervision presents in modern times as the largest obstacles for growing activities to work. Against this background, the purpose of this thesis is to find a way forward for gardening as a school activity that increases students' consciousness of sustainable food production.  Forest gardening is a cultivation model within the Agro Forestry movement. Using literature study as a methodology, it is found that forest gardening principles can be applied to school gardening to solve the identified isues with cultivation in primary schools.  Regarding forest gardening principles, one can create a cultivation that occupies a small  area and recieves the ideal microclimate with an array of plants with different hights. This cultivation model lowers the work time required and the need for summer supervision. In addition, this cultivation gives the ecosystem increased biodiversity and carbon storage. Another advantage with this cultivation model is that through plant selection, one can control harvest times to spring and autumn, when students are in school. However, it appears that this cultivation model is knowledge- intensive during the construction phase and that it is a good idea to get outside help from an expert, for example, a gardener with expertise in forest gardening. A design proposal for lower school grades is also included, with a plant list and design plan that can be adapted and suited to schools. / Odling är ett kreativt redskap i grundskolans ämnesundervisning. Det är en utomhusaktivitet som skapar rörelse. Trädgårdsaktiviteter ger gynnsamma effekter för det sociala samspelet i elevgruppen och odling är ett sätt att öka elevernas medvetenhet om vår matproduktion. Dessa argument framgår som betydelsefulla i tidigare studier där skolpersonal har motiverat sina skäl till att  driva skolträdgårdar. Skolträdgårdar har dock i alla tider brottats med problem. Att få resurser att räcka till för skötsel och lektionsplanering och att klara av sommartillsynen, framträder i modern tid som de största hindren för att få odlingarna att fungera. Mot den bakgrunden är syftet med denna uppsats att söka en väg frammåt för skolträdgården, som är hållbar i skolornas verksamhet och som ökar elevernas medvetenhet om en miljömässigt hållbar matproduktion.  Skogsträdgården är en odlingsmodell inom Agro Forestry rörelsen. Med litteraturstudie som metod undersöks här vilka av skogsträdgårdens principer som kan tillämpas i en skoltärdgård för att möta de identifierade problemen för odling inom grundskolan.  Det framgår att man med idéer från skogsträdgården kan skapa en odling som tar en liten yta i anspråk och får ett gynsammt microklimat tack vare växter i olika höjdskickt. Odlingsmodellen kräver en låg skötselinsats i förhållande till skörd tack vare ståndortsanpassning, marktäckning, själförsörjning av näring och perenna grödor som tillsammans minskar behovet av bevattning och skötsel. Resultatet påvisar att man med hjälp av flera av skogsträdgårdens odlingsprinciper kan minska behovet av arbetstid och sommarlovsskötsel. Dessutom ger odlingen ekosystemtjänster som ökad biologisk mångfald och kollagring. Ytterliggare en fördel är att man med hjälp av växtval kan styra skördetiden till vår och höst, då eleverna är på plats i skolan. Det framkommer dock att odlingsmetoden är kunskapskrävande under anläggningsfasen och att det är en god idé att vid etableringen ta hjälp utifrån av expertis som tillexempel en trädgårdsmästare med kompetens inom skogsträdgårdsodling.  Här presenteras också ett designförslag fö en grundskola, med växtlista och design som kan anpassas och modifieras till att passa på flera skolor.
3

Impact of climate change on the agro-ecological innovation of coffee agroforestery systems in central Kenya / Impact des changements climatiques sur les innovations agro-écologiques des systèmes agroforestiers du café au Kenya central

Gebreeyesus, Kinfe Asayehegn 28 April 2017 (has links)
Le changement climatique et la variabilité ont des répercussions graves dans le secteur agricole des régions tropicales. Le secteur du café est sensible au changement climatique car il nécessite une température relativement froide et une plus grande durée des pluies. L'adaptation au changement climatique dans l'agroforesterie du café est donc importante pour traiter les impacts, mais il existe des obstacles et des limites. Le but de cette thèse était d'analyser les stratégies d'adaptation au changement climatique au centre du Kenya. Nous avons étudié différentes étapes de l'adaptation qui incluent (1) les connaissances sur le changement climatique et l'adaptation, la motivation à l'adaptation, (2) le choix actuel des stratégies d'adaptation et leurs déterminants, (3) les rôles du système d'innovation et du contexte institutionnel. Cette étude repose sur quatre sources d'information: - (1) groupes de discussion sur des questionnaires pré-définis, (2) enquêtes auprès des ménages, (3) entrevues auprès des intervenants et (4) données climatiques historiques sur le contexte de quatre types de systèmes de productions dans l’agriculture : les cultures vivrières, le café spécialisé, les systèmes diversifiés café-laiterie et les systèmes laitiers spécialisés, dans les zones caféières et vivrières. L'analyse des tendances de Mann-Kendal et l'estimateur de la pente de Sen ont été utilisées pour comparer les connaissances des agriculteurs sur les changements climatiques et l’historique des données climatiques, tandis que le modèle de Heckman a été utilisé pour analyser les stratégies d'adaptation et leurs déterminants. Les résultats soulignent des cohérences entre les connaissances des agriculteurs et l'analyse historique des données pour la température mais des incohérences avec le changement des précipitations. L'analyse de la perception par les agriculteurs révèle que les précipitations diminuent radicalement au fil du temps, alors qu'aucun élément de preuve concernant les précipitations ne permet d'appuyer la perception des agriculteurs. L'incohérence est donc corroborée par l'analyse des modèles. Les agriculteurs du secteur du café et des cultures vivrières se sont adaptés différemment aux changements climatiques. Les agriculteurs qui sont conscients des changements sont plus disposés à explorer les stratégies d'adaptation. Une partie des agriculteurs qui ne perçoivent pas le changement climatique adoptent des stratégies d’adaptation à des facteurs autres. L'adaptation au changement climatique est également déterminée par la performance institutionnelle et les différences de systèmes sectoriels d'innovation. La comparaison entre les secteurs du café et des produits laitiers révèle ainsi que les stratégies des acteurs du café sont limitées. En ce qui concerne l’élaboration des politiques, cette thèse contribue aux politiques d’accompagnement de l’adaptation au niveau des ménages, aux politiques de recherche agronomique et de négociation des accords internationaux. Les recommandations politiques au niveau des ménages se différentient selon trois scénarios. En premier lieu de l’intensification dans le café par l’innovation technologique. Les deux autres options politiques sont dans la diversification sectorielle dans la production laitière qui dépend de leur niveau de rentabilité. Les résultats de cette étude sont issus d’enquêtes sur l’analyse des systèmes d’innovation. D’autres options politiques sont proposées dans le développement de nouvelles infrastructures, des subventions pour accroitre les potentiels d’adaptation. Nous recommandons enfin de nouveaux sujets de recherche pour le futur. / Climate change and variability is the most widespread anthropogenic challenge affecting agricultural production and productivity particularly in the tropics. Coffee sector is sensitive to climate change as it requires relatively cold temperature and higher rainfall duration. Adaptation to climate change in the coffee agroforestry is, therefore, important to address the impacts, but there are barriers, and limits. The aim of this Thesis was to analyze the adaptation strategies to climate change in Central Kenya. We studied the steps in adaptation, which includes (1) the knowledge on climate change and adaptation, the motivation towards adaptation, (2) current choices of households’ adaptation strategies, and their determinants, (3) the roles of innovation system and institutional context to support adaptation. This study was based on four sources of information: - (1) Focus Group Discussions to predefine the questionnaires, (2) household surveys, (3) stakeholders interview, and, (4) historical climate data. The data collection considered four farming typologies; - food crops, specialized coffee, diversified coffee-dairy and specialized dairy farming systems in the coffee and food crops zones. Mann-Kendal trend analysis and Sen’s slope estimator were used to compare the farmers’ knowledge of climate change with the historical climate data, while Heckman model was used to analyze adaptation strategies and their determinants. The findings explore consistent results between farmers’ knowledge and historical data analysis for temperature, while inconsistency is observed in rainfall change. Analysis of farmers’ perception revealed rainfall is radically declining over time, while no evidence in rainfall record is found to support the farmers’ perception. The inconsistency is therefore, substantiated with analysis of patterns. Coffee and food crop farmers are found to adapt to climate change differently. Farmers who are aware of the changes are found more willing to explore adaptation strategies although some of the farmers who do not perceive the climate is changing are also adopting strategies for factors other than perception. The comparison between coffee and dairy sectors found that actors in the coffee are limited, the system is highly centralized with limited options for farmers to process and market their products, while the dairy sector is informally controlled by demand based business and comparatively, numerous actors. We conclude in this study that the patterns in rainfall affects the farming activities of the study area higher than the annual changes. Consequently, farmers adopt a series of adaptation strategies in response to their perception of changes in climate and economic pressure in the farm. This adaptation to climate change also depends on the nature of actors’ interaction and institutional context. In relation to policy development, this Thesis contributes to household level adaptation policies, research policies and international agreements and negotiations. The household level policy recommendations consists of three scenarios. Farmers’ intensification in coffee applying the right technological innovations. The second and third policy options are the diversification to dairy and complete sectoral transformation to dairy depending on the profitability and adaptation level of the sectors. The results in this study are derived from surveys and analysis of innovation systems. Other strategies such as new infrastructural development and institutional subsidies could be potential for adaptation. We therefore, recommend, these could be potential future research topics.
4

A agroecologia como alternativa frente à modernização da agricultura: um estudo de caso no município de Coronel Vivida PR / The agro-ecology alternative faced on the agriculture modernization: a case report in Coronel Vivida town

Stasiak, Ana Paula 08 July 2013 (has links)
Made available in DSpace on 2017-05-12T14:41:54Z (GMT). No. of bitstreams: 1 Ana_Paula_Stasiak.pdf: 6576934 bytes, checksum: 2a7f5dfaa2eccfd9cce5a56afda8f804 (MD5) Previous issue date: 2013-07-08 / The agro-ecological farming has got started by social movements in favor to the rural sustainable development based on environmental, social and economic. Agroecologyis presented as an alternative to modernization of agriculture that repair environmental damage and social damage caused by the green revolution technology disseminated and adopted by the Brazilian government as a development policy based on the economic growth. This paper aims to analyze the agro-ecology alternatively forward the modernization process of the agriculture and the different territorialities provided by the two forms of production, as well as identify the limits and difficulties of territorial agro-ecological practices in Coronel Vivida, held bibliographic review the topic addressed and fieldwork, using a questionnaire addressed to eleven farmers who have comprised three distinct groups related to agro-ecology in the town: Farmers Convention with SAFs; 2) Agro-ecological Farmers; 3) Farmers Convention-Former Agro-ecological Farmers. And interviews with representatives of institutions related to agriculture and agroecology family whose work is in the town. The study of these three groups with different production and commercial organizations had allowed us to observe the process of territorialization and deterritorialization of simultaneous agro-ecological practices, the latter prevails. Another methodology used to characterize the properties sustainable, based on agro-ecological principles, as well as differentiate the analysis was made landscapes through sketches and photographs of the properties studied. This paper outlines the main difficulties faced by the town farmers relationed to agro-ecological production, as well as the main factors which have influenced the abandonment of agro-ecological practices by the Coronel Vivida agro-ecological farmers. / A agricultura agroecológica surge de movimentos sociais em favor de um desenvolvimento rural sustentável, baseado nas condições ambientais, sociais e econômicas. A Agroecologia é apresentada como alternativa a modernização da agricultura visando reparar os danos ambientais e prejuízos sociais causados pela tecnologia disseminada pela revolução verde e adotada pelo Estado brasileiro como política desenvolvimentista baseada no crescimento econômico. Com o objetivo de analisar a Agroecologia como alternativa frente ao processo de modernização da agricultura e as diferentes territorialidades proporcionadas pelas duas formas de produção, assim como, identificar os limites e dificuldades de territorialização das práticas agroecológicas em Coronel Vivida, realizou-se revisão bibliográfica sobre o tema abordado e trabalho de campo, com aplicação de questionário dirigido à onze agricultores familiares que compõem três grupos distintos relacionados com a Agroecologia no município: 1) Agricultores Convencionais com SAFs; 2)Agricultores Agroecológicos; 3)Agricultores Convencionais Ex-Agricultores Agroecológicos. E entrevistas com representantes de instituições ligadas a agricultura familiar e a Agroecologia que atuam no município. O estudo desses três grupos que apresentaram organizações produtivas e comerciais diferentes nos permitiu constatar o processo de territorialização e desterritorialização simultâneas das práticas agroecológicas, prevalecendo esse último. Outra metodologia utilizada para caracterizar os estabelecimentos sustentáveis, baseados nos princípios agroecológicos, assim como, diferenciar as paisagens constituídas foi à análise através de croquis e fotografias dos estabelecimentos em estudo. O presente texto aponta as principais dificuldades enfrentadas pelos agricultores do município em relação à produção agroecológica, assim como, os principais fatores que influenciaram no abandono de práticas agroecológicas por parte dos ex-agricultores agroecológicos de Coronel Vivida.
5

A agroecologia como alternativa frente à modernização da agricultura: um estudo de caso no município de Coronel Vivida - PR / The agro-ecology alternative faced on the agriculture modernization: a case report in Coronel Vivida town

Stasiak, Ana Paula 08 July 2013 (has links)
Made available in DSpace on 2017-07-10T17:30:17Z (GMT). No. of bitstreams: 1 Ana_Paula_Stasiak.pdf: 6576934 bytes, checksum: 2a7f5dfaa2eccfd9cce5a56afda8f804 (MD5) Previous issue date: 2013-07-08 / The agro-ecological farming has got started by social movements in favor to the rural sustainable development based on environmental, social and economic. Agroecologyis presented as an alternative to modernization of agriculture that repair environmental damage and social damage caused by the green revolution technology disseminated and adopted by the Brazilian government as a development policy based on the economic growth. This paper aims to analyze the agro-ecology alternatively forward the modernization process of the agriculture and the different territorialities provided by the two forms of production, as well as identify the limits and difficulties of territorial agro-ecological practices in Coronel Vivida, held bibliographic review the topic addressed and fieldwork, using a questionnaire addressed to eleven farmers who have comprised three distinct groups related to agro-ecology in the town: Farmers Convention with SAFs; 2) Agro-ecological Farmers; 3) Farmers Convention-Former Agro-ecological Farmers. And interviews with representatives of institutions related to agriculture and agroecology family whose work is in the town. The study of these three groups with different production and commercial organizations had allowed us to observe the process of territorialization and deterritorialization of simultaneous agro-ecological practices, the latter prevails. Another methodology used to characterize the properties sustainable, based on agro-ecological principles, as well as differentiate the analysis was made landscapes through sketches and photographs of the properties studied. This paper outlines the main difficulties faced by the town farmers relationed to agro-ecological production, as well as the main factors which have influenced the abandonment of agro-ecological practices by the Coronel Vivida agro-ecological farmers. / A agricultura agroecológica surge de movimentos sociais em favor de um desenvolvimento rural sustentável, baseado nas condições ambientais, sociais e econômicas. A Agroecologia é apresentada como alternativa a modernização da agricultura visando reparar os danos ambientais e prejuízos sociais causados pela tecnologia disseminada pela revolução verde e adotada pelo Estado brasileiro como política desenvolvimentista baseada no crescimento econômico. Com o objetivo de analisar a Agroecologia como alternativa frente ao processo de modernização da agricultura e as diferentes territorialidades proporcionadas pelas duas formas de produção, assim como, identificar os limites e dificuldades de territorialização das práticas agroecológicas em Coronel Vivida, realizou-se revisão bibliográfica sobre o tema abordado e trabalho de campo, com aplicação de questionário dirigido à onze agricultores familiares que compõem três grupos distintos relacionados com a Agroecologia no município: 1) Agricultores Convencionais com SAFs; 2)Agricultores Agroecológicos; 3)Agricultores Convencionais Ex-Agricultores Agroecológicos. E entrevistas com representantes de instituições ligadas a agricultura familiar e a Agroecologia que atuam no município. O estudo desses três grupos que apresentaram organizações produtivas e comerciais diferentes nos permitiu constatar o processo de territorialização e desterritorialização simultâneas das práticas agroecológicas, prevalecendo esse último. Outra metodologia utilizada para caracterizar os estabelecimentos sustentáveis, baseados nos princípios agroecológicos, assim como, diferenciar as paisagens constituídas foi à análise através de croquis e fotografias dos estabelecimentos em estudo. O presente texto aponta as principais dificuldades enfrentadas pelos agricultores do município em relação à produção agroecológica, assim como, os principais fatores que influenciaram no abandono de práticas agroecológicas por parte dos ex-agricultores agroecológicos de Coronel Vivida.
6

A Multi-Scale Assessment of Land-Use Impacts on Hydrologic Ecosystem Services in the Vouga Basin, North-Central Portugal

Hawtree, Daniel Robert 20 December 2019 (has links)
Sustainable water resource management requires understanding how hydrologic processes are impacted by environmental management and land-use decisions across multiple spatial and temporal scales. A key concept in this respect is hydrologic ecosystem services (HES), which are the water related ‘goods’ produced by the environment which are valuable to humans. This dissertation assesses a range of topics concerning HES in the Vouga basin (north-central Portugal), and their connection with land-cover and land-use practices. Specifically, the relationship between changes in forest and agricultural land-cover and management practices, and associated changes in HES were examined using a range of statistical and modeling approaches. To quantify the effects of different agricultural scenarios on both HES and potential stakeholders, the ‘Soil and Water Assessment Tool’ (SWAT) was utilized, in conjunction with economic assessment methods. The first research section (Section 6) of the dissertation assesses the trends in streamflow quantity and yield in the Águeda watershed (a sub-basin of the Vouga) over a 75-yr period which coincided with large-scale afforestation of Pinus pinaster and (later) Eucalyptus globulus. Counter to the findings from meta-analysis studies of the effect of forest change on water availability, this study did not detect statistically significant trends in streamflow. By contrast, these findings support the view that there are prerequisite climatic, pedological, and eco-physiological watershed conditions that are necessary to observe hydrologic impacts at the watershed scale (which are not present in the Águeda watershed). By contrast, the significant changes which were detected are related to baseflow, which correspond with different periods of afforestation, and may be attributable to the promotion of soil water repellency under the mature pine and eucalypt stands. In the second research section (Section 7), an assessment is carried out on the hydrologic and nitrate dynamics at the whole basin scale, using the SWAT model. This assessment indicated that there is a high degree of variability in nitrate export from the different parts of the basin, with the highest rates coming from the lower (agriculturally dominated portion) of the basin. The main flow pathways for nitrate export were found to be leaching from agricultural land-cover types, which consistently had the highest export for all land-use and pathways. These findings indicate that the water bodies at the highest risk of nitrate pollution in the Vouga basin are the groundwater aquifers. The final research section (Section 8) utilizes the SWAT model to examine how reduced rates of fertilizer inputs would affect nitrate leaching, crop yields, and agricultural profitability in the lower Vouga basin. This research found that reduced rates of fertilization would reduce the amount of leached nitrate substantially, but that this would also lead to a large decrease in crop yield and profitability. A large difference in the inefficiency (i.e. crop production vs. nitrate export) between different HRUs was found, which could provide a focus for potential management action. This research strongly indicates that such actions may be needed to reduce the negative impacts of this pollution on the value of the groundwater aquifers, and to avoid associated costs which are otherwise passed on to local water users (e.g. through higher water treatment costs). The overall findings of the dissertation highlight the importance of the upper (forested) basin as a drinking water supply area, given the prevalence of nitrate pollution in the lower basin. However, the historic afforestation in the Vouga basin has resulted in a reduction in baseflow, which is negative from a drinking water supply perspective. Therefore, while the forested uplands are beneficial from water quality standpoint (compared to intensive agriculture), they also have altered flow patterns in a manner which will reduce available supply. The findings from the upper basin contrast sharply with the lower basin, where there are potentially large negative HES impacts due to current agricultural practices. These practices will primarily impact groundwater aquifers, and therefore the water quality within the lower basin receive little benefit from the relatively high-quality water from the upper basin. This highlights the importance of considering the interconnectivity of HES across spatial scales, which will depend on the specific site characteristics of the river basin.

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