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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.
181

Agroecology: an assessment of Campi Aperti transformative potential

Rossi, Giulia January 2022 (has links)
Food systems are central to human well-being and development. Nevertheless, they also represent a significant source of environmental and social negative impacts. Additionally, the recent and multiple disruptions, like the coronavirus pandemic and the Ukraine war, have demonstrated that the systems are unprepared to face unforeseen shocks. For these reasons, in recent years, the concept of agroecology has been rediscovered and emphasized. The holistic framework proposed by agroecology is considered an innovative solution as it not only encompasses environmental measures for agriculture but also social and economic ones. Nevertheless, there is no  official or precise definition of the criteria that need to be satisfied for a system to be considered agroecological. This situation increases the risk that mainstream food systems will appropriate the term  without undergoing the fundamental transformational actions that are needed to create sustainable food systems. This thesis applies a  framework with which to test the level of transformation achieved by Campi Aperti, an agroecological system in northern Italy, to understand the extent  of the transformability they propose through the development of ecological farming methods and local farmer’s markets. The assessment is based on three sources of data: a summary of the association documents, semi-structured interviews, and a survey. The association has obtained an optimal score in almost all the indicators of progress towards transformation. Nevertheless, the results have also identified difficulties, challenges, and some areas for improvement, like access to nature, the ability for everyone to participate, and the relationships with the government. The results have highlighted the importance of undergoing an assessment of agroecological systems, not only to understand their transformability potential but also to help in defining the themes that need to be addressed to create a truly innovative agroecological system.
182

[pt] POLICULTURA NO MUNICÍPIO DE NOVA FRIBURGO, RJ: PROCESSO DE EVOLUÇÃO E RELAÇÕES SOCIEDADE-NATUREZA / [en] POLYCULTURE IN NOVA FRIBURGO, RJ: EVOLUTION PROCESS AND NATURE-SOCIETY RELATIONS

CONRADO CHERMUT STROLIGO 26 October 2016 (has links)
[pt] Como se observa na história de Nova Friburgo-RJ, desde o tratado firmado entre Dom João VI e o empresário suíço Nicolau Gachet, em 1818, para a implantação da colônia, o caráter produtivo de alimentos para a metrópole do Rio de Janeiro estava prescrito. Porém, após a chegada dos primeiros imigrantes suíços em 1819, devido a problemas de adaptação cultural, econômicos e ambientais, os objetivos iniciais da colônia foram substituídos pela necessidade de sobrevivência dos colonos, o que favoreceu a miscigenação cultural entre os mesmos e lusos, e ainda, indígenas e afro-brasileiros, favorecendo a formação de uma agricultura de caráter policultural. No decorrer de seus quase dois séculos de existência, o município presenciou a produção de alimentos diversificados no chamado meio rural, quanto no seu centro urbano, onde, ainda encontram-se presentes cultivos com fins de parcial subsistência em quintais produtivos, mesmo que de modo pulverizado na paisagem friburguense. No presente trabalho serão rastreadas as características comuns entre os cultivos dos entrevistados, sendo quatro presentes no distrito-sede e dois em distritos rurais de Nova Friburgo, a fim de analisar sua relação com o processo histórico, documentado, de formação da agricultura policultural de subsistência no município. Todos os manejos possuem caráter biodiverso e policultural na produção de alimentos sem o uso do fogo com fins de fertilização de solo e nenhum tipo de agroquímico. Portanto, este trabalho visa investigar a relação destes espaços produtivos, com as práticas agrícolas historicamente evidenciadas no município, a fim de verificar a potencial existência de vínculo cultural entre os casos do passado e do presente. E é neste contexto entre o atual e o pretérito, o novo e o velho, o interno e o externo que se dá a presente pesquisa. / [en] As noted in the history of Nova Friburgo-RJ since it s creation through the treaty between Dom João VI and the Swiss businessman Nicholas Gachet in 1818 for the implementation of the colony, the food production regarding the supplying Rio de Janeiro city s demand was prescribed. However, after the arrival of the first Swiss immigrants in 1819, due to problems of cultural adaptation, economic and environmental, the initial objectives of the colony were replaced by the need for survival of the settlers, which favored the cultural miscegenation between them and Portuguese s, indigenous and afroamericans, favoring the formation of a polycultural character of agriculture. During nearly two centuries of existence, the city witnessed the production of diversified food types in the so-called rural areas and in its urban center, where there are still present crops with partial subsistence purposes in productive backyards, notwithstanding they are pulverized in Nova Friburgo s landscape. In this work we will seek to analise the common characteristics between the crops of the enquired people, four of those living in the urban district and two in rural districts of Nova Friburgo, in order to analyze its relationship with the documented historical process, of polycultural agriculture subsistence emergence in the city. All managements have biodiverse character and polycultural in food production without the use of fire for fertilizing the soil neither of agrochemicals. Therefore, this paper aims to investigate the relationship of these productive areas, with agricultural practices historically evidenced in the municipality in order to verify the potential existence of a cultural link between the cases of the past and present. It is in this context between the present and the past, the new and the old, the internal and the external that the present research is proposed.
183

Arte y agricultura: estrategias artísticas para la transición a una agricultura sustentable

Puerto Espinós, Celia 25 October 2021 (has links)
[ES] La presente investigación se centra en buscar los vínculos entre la práctica artística y la agrícola. Tras el estudio de ambas, se demuestra cómo se apoyan y nutren entre sí. Se realiza una breve revisión histórica de los 10.000 años de agricultura evidenciando cómo ha sido un tema muy relevante en las primeras manifestaciones gráfico-plásticas y el papel que ha ocupado en los movimientos artísticos posteriores hasta centrarnos en el arte contemporáneo. El estudio pretende dar a conocer las posibilidades que ofrece el arte utilizando estrategias artísticas y estéticas para fomentar prácticas agrícolas sustentables. Para ello, se hace uso de una metodología cualitativa y de investigación a través del arte con la elección de un repertorio de proyectos artísticos y su análisis. Finalmente, se eligen cinco casos de estudio actuales donde se trabaja el arte y la agricultura desde diferentes vías de investigación para analizarlos con más profundidad. / [CA] La present investigació se centra en buscar els vincles entre la pràctica artística i l'agrícola. Després de l'estudi d'ambdues, es demostra com se secunden i nodreixen entre si. Es realitza una breu revisió històrica dels 10.000 anys d'agricultura evidenciant com ha sigut un tema molt rellevant en les primeres manifestacions gràfic-plàstiques i el paper que ha ocupat en els moviments artístics posteriors fins a centrar-nos en l'art contemporani. L'estudi pretén donar a conéixer les possibilitats que ofereix l'art utilitzant estratègies artístiques i estètiques per a fomentar pràctiques agrícoles sustentables. Per tant, es fa ús d'una metodologia qualitativa i d'investigació a través de l'art amb l'elecció d'un repertori de projectes artístics i la seua anàlisi. Finalment, es trien cinc casos d'estudi actuals on es treballa l'art i l'agricultura des de diferents vies d'investigació per a analitzar-los amb més profunditat. / [EN] This research focuses on the relationship between artistic and agricultural practice. After studying both, it shows how they support and nourish each other. A brief historical review of the 10,000 years of agriculture is carried out, showing how it has been a very relevant theme in the first graphic-plastic manifestations and the role it has played in later artistic movements and, more recently, in contemporary art. The study aims to highlight the possibilities offered by art using aesthetic strategies to promote sustainable agricultural practices. In order to do so, qualitative methodologies and art based research are used to analyse a series of art contemporany projects. Finally, five case studies where art and agriculture converge are chosen for an in-depth study. / Puerto Espinós, C. (2021). Arte y agricultura: estrategias artísticas para la transición a una agricultura sustentable [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/175569
184

Agroecological innovation in Challa : Intercultural dialogue and participatory research in knowledge and information exchange

Tarazona Machicao, Mateo January 2013 (has links)
The development of agroecological food systems in the Andes provides a fruitful study environment for understanding innovation processes in participatory research. In this particular context two knowledge based communities - the modern scientific and the traditional indigenous form an intercultural dialogue that frames the conditions for innovation to be developed and sustained. This thesis presents an exploratory case study of the Communal Agricultural Risk Management project in Challa, Bolivia. A project that aims at combining local knowledge with technological innovation as a strategy to reduce vulnerability to climate risk by strengthening local production systems. The study applies a sociotechnical approach to agricultural knowledge and information systems to analyse how innovations are facilitated and sustained by the projects main actor - the local stakeholder and participatory researcher denominated as Yapuchiri. The main findings of the study conclude that innovation is facilitated but not sustained as vertical linkages between actors and diverging perceptions of personal benefits, project goals and material/immaterial resources limit the performance of the system. The study consequently suggests that the Yapuchiris have to reach consensus on mutual benefits with the collective coordination of agroecological practices in order to find equitable partnerships that help to sustain their work after the project has ended.
185

Expérimentations de pratiques agroécologiques réalisées par des agriculteurs : proposition d’un cadre d’analyse à partir du cas des grandes cultures et du maraîchage diversifié dans le département de la Drôme / Analysis of farmers' experiments on agroecological practices : how does it help to change technically?

Catalogna, Maxime 07 December 2018 (has links)
L’intensification des processus écologiques proposée par l’agroécologie est très dépendante du contexte agricole. Un renouvellement des savoirs sur l’exploitation agricole est nécessaire pour adapter chaque pratique agroécologique. Dans cette thèse, nous avons étudié l'activité d'expérimentation des agriculteurs, définie comme un processus de mise à l’épreuve de pratiques embarquant des hypothèses tant sur leur mise en œuvre que sur les processus agroécologiques que ces pratiques visent à induire. Notre travail est basé sur des enquêtes auprès de 17 agriculteurs majoritairement drômois, étant soit en maraîchage diversifié, soit en grandes cultures.Nous avons formalisé l'activité d'expérimentation des agriculteurs avec deux notions : la situation expérimentale (SE) et l'itinéraire d'expérimentation (ITE). Elles concernent respectivement le temps court (annuel ou infra-annuel) et le temps long (pluri-annuel) et font l'objet des deux premiers chapitres de résultat. Dans le premier, nous avons construit un cadre d’analyse des SEs comprenant des phases de conception, de réalisation et d’évaluation. A partir de ce cadre, nous avons étudié la diversité d’un échantillon de 181 SEs et identifié 10 groupes de SEs organisés en 4 clusters. La typologie obtenue dépend d'une variable particulière qui est le type de lien aux SEs précédentes. Dans le deuxième chapitre de résultat, nous avons approfondi ces liens en nous intéressant aux ITEs, définis comme la combinaison de différentes SEs portant sur une thématique agroécologique particulière. Nous avons identifié 4 types d'ITE qui diffèrent par leur intensité expérimentale, les liens entre SEs et l'émission ou non de nouvelles branches expérimentales.Le troisième chapitre de résultat traite la question du développement des connaissances des agriculteurs grâce à leurs expérimentations. Après avoir caractérisé différentes formes de connaissances, plus ou moins stabilisées, nous proposons trois processus de développement de connaissances avancées grâce aux expérimentations menées.Le modèle SE/ITE est prometteur pour accompagner les agriculteurs. La frise chronologique des SEs organisées en ITE représente un outil de réflexivité potentiel. / The intensification of ecological processes proposed by agroecology is highly dependent on the agricultural context. A renewal of farming knowledge is necessary to adapt each agro-ecological practice. In this thesis, we studied farmers’ experiments, defined as a process of testing practices that embody hypotheses both on their implementation and on the targeted agro-ecological processes. Our work is based on surveys of 17 farmers, mainly Drôme farmers, who were either diversified market gardeners or cereal farmers.We have formalized the farmers’ experiments with two notions: the experimental situation (SE) and the experimentation itinerary (ITE). They concern respectively short time (annual or infra-annual) and long time (multi-year) and are the subject of the first two chapters of the results. In the first one, we built an analytical framework that includes design, implementation and evaluation phases. From this framework, we studied the diversity of a sample of 181 SEs and identified 10 groups of SEs organized into 4 clusters. The typology obtained depends on a particular variable which is the type of link to previous SEs. In the second chapter of the result, we have deepened these links by focusing on ITEs, defined as the combination of different SEs on a particular agro-ecological theme. We identified 4 types of ITEs that differ in their experimental intensity, the links between SEs and the emission or not of new experimental branches.The third chapter of the result deals with the question of farmers developing knowledge through their experiments. After having characterized different forms of knowledge, more or less stabilized, we propose three processes for the development of advanced knowledge through experimentation.The SE/ITE model is promising to support farmers. The chronological timeline of SEs organized in ITEs represents a potential reflexivity tool.
186

"Agroecologia & desenvolvimento: estudo de caso do Grupo Curupira, Jaboti-PR" / Agroecology and Development: The Curupira Group study case, Jaboti, PR

Cerveira, Ricardo 28 April 2003 (has links)
A preocupação com a conservação do meio ambiente é crescente em tempos atuais. Concomitantemente, tem-se a necessidade de produzir alimentos em larga escala; o que favoreceu o aparecimento de sintomas indesejáveis no meio ambiente. Alternativas ao sistema convencional de produção agropecuária, como a adoção de sistemas agrícolas baseados na Agroecologia, tornaram-se práticas inadiáveis. Neste trabalho procurou-se caracterizar o efeito da mudança do sistema agrícola atual pelo agroecológico em um grupo de pequenos produtores de açúcar mascavo do norte do Paraná, denominado Grupo Curupira. Para aprofundar a avaliação da nova tecnologia adotada pelo Grupo Curupira, um experimento de campo elaborado na Estação Experimental de Agronomia de Piracicaba do Instituto Agronômico de Campinas (IAC) fez, também, parte do objeto de estudo deste trabalho. Os resultados obtidos permitiram concluir que, em função da mudança do sistema agrícola de produção, o Grupo Curupira obteve melhorias em atributos de desenvolvimento social e econômico. No tocante a aspectos tecnológicos, ainda se tornam necessárias adequações para melhoria dos índices de rentabilidade e produtividade. / Recently, there has been an increasing concern about the environment preservation. On the other hand, there’ve the need to produce huge quantities of food, which has a great impact in environment. A lot of effort has been done to develop alternative agricultural systems, such as the Agroecology. This research analyzed the effect of the exchange from an usual agricultural system to the Agroecology in group of small brown sugar growers from the Parana State called Grupo Curupira. To evaluate the technology used by the growers, an field experiment was done in Agronomy Research Center of the "Instituto Agronômico de Campinas (IAC)", located in Piracicaba. The final results showed that the exchange in the agricultural system provided a good social and economical development for growers group. However, the technical evaluation reveled those adjustments to improve the yield and profit indexes are needed.
187

Nas fissuras do concreto: política e movimento nas hortas comunitárias da cidade de São Paulo / Within concrete cracks: politics and movement at community gardens in São Paulo

Machini, Mariana Luíza Fiocco 24 November 2017 (has links)
Esta dissertação analisa algumas das hortas urbanas comunitárias da cidade de São Paulo. Trata-se de uma etnografia que explora as conexões, motivações e formas de ação desses agrupamentos autogeridos de voluntários que criam e mantêm espaços de plantio em áreas públicas. São tratadas de maneira mais detida três delas: a Horta das Corujas, no bairro da Vila Beatriz, a Horta do Centro Cultural São Paulo, no bairro Vergueiro e a Horta dos Ciclistas, na Avenida Paulista. A intenção dessa análise, no entanto, não é se ater a territórios fixos, e sim apreender os movimentos propiciados pela prática das hortas comunitárias na cidade. Dessa maneira, são aqui traçadas algumas das relações entre essas hortas e outras formas de agricultura urbana em São Paulo, os entrelaçamento e perspectivas de co-construções que emergem entre humanos e não humanos, além de suas relações com instâncias políticas formais. A interação entre as ações no espaço público, as técnicas e os ensinamentos de agroecologia propagados pelas hortas e a rede de trocas que opera entre elas expõe maneiras de se vincular à cidade que são permeadas por uma noção de política do cotidiano, a qual não se encontra apenas nas relações com o e do Estado. / This dissertation analyses some of the community urban gardens of São Paulo, SP. We have carried out an ethnography exploring the connections, motives and ways of action of those selfmanaged groups of volunteers, who create and keep cultivating spaces amidst public areas. We focus of three urban gardens: Horta das Corujas [Owls Garden], at Vila Beatriz neighborhood, the São Paulo Cultural Center Garden, at Vergueiro neighborhood; and Horta dos Ciclistas [Cyclers Garden], at Paulista Avenue. This analysis is not restrained, however, to fixed territories, but rather apprehends the movements engendered by community garden practices in the city. Thus, we trace some relations between those gardens and other forms of urban agriculture in São Paulo, their intertwining and the co-construction perspectives that emerges among humans and non-humans, as well as their relations with formal public agents. The interaction among actions performed in public spaces, the agroecology techniques and teachings, and their exchange network are embedded with a concept of everyday politics, practiced not only by or in face of the State.
188

Contribution des pollinisateurs dans la production de colza et de tournesol en zone atelier « Plaine et Val de Sèvre » / Contribution of pollinators to oilseed rape and sunflower production in the zone atelier « Plaine and Val de Sèvre ».

Perrot, Thomas 15 June 2018 (has links)
La pollinisation entomophile est essentielle pour la production de 70% des cultures à travers le monde. Cependant la contribution des pollinisateurs dans la production agricole reste peu renseignée ainsi que les insectes qui sont impliqués. De plus, lorsque la contribution des pollinisateurs est quantifiée, le bénéfice est calculé à des échelles biologiques ou dans des conditions simplifiées qui peuvent être non représentatifs des bénéfices à l’échelle de la parcelle. Par ailleurs, les possibles interactions entre les pollinisateurs et les pratiques agricoles ne sont généralement pas pris en compte. L’objectif général de cette thèse était donc de quantifier la contribution des pollinisateurs directement dans les parcelles agricoles dans deux cultures fréquemment retrouvées en Europe, le colza et le tournesol. Ces estimations sont réalisées à l’échelle de la parcelle ainsi qu’à l’échelle de la plante pour comprendre les mécanismes qui permettent l’augmentation de la production agricole. Ces études nous ont permis aussi d’identifier les principaux pollinisateurs de ces deux cultures.Dans un premier temps, nous avons quantifié le bénéfice des pollinisateurs dans les rendements de tournesol et de colza. Nous montrons que le colza et le tournesol partagent une même guilde de pollinisateurs, les abeilles domestiques. Les abeilles sauvages sont aussi d’importants pollinisateurs pour le colza. Les pollinisateurs augmentent les rendements de colza de plus de 35% et ceux du tournesol de 40%, à l’échelle de la parcelle. A l’échelle de la plante, que ce soit pour le colza et le tournesol, les pollinisateurs augmentent le succès de pollinisation et donc le nombre de graines par plante.Dans un deuxième temps, nous avons comparé le bénéfice des pollinisateurs par rapport à ceux des pratiques agricoles en termes de rendement et de gain monétaires dans les parcelles de colza, tout en regardant plus précisément leurs possibles interactions. Nous montrons que le bénéfice des pollinisateurs dans les rendements s’additionnent à ceux des pratiques agricoles excepté avec les insecticides qui réduisant la contribution des pollinisateurs. De plus, nous montrons que les pollinisateurs sont d’importants contributeurs du rendement et des revenus agricoles en augmentant le bénéfice des agriculteurs de 250 € par hectare alors qu’au contraire plusieurs pratiques peuvent être très couteuses pour ces mêmes agriculteurs. Finalement, nous étudions l’effet des pollinisateurs sur la qualité lipidique des graines de colza qui est une autre facette de la production agricole. Nous montrons que les abeilles domestiques améliorent la qualité des graines en augmentant le pourcentage d’acides gras insaturés tout en réduisant les acides gras trans- et saturés. Pour certaines années, les abeilles domestiques augmentent aussi le pourcentage de lipide par graine.En conclusion, nous montrons que les pollinisateurs sont essentiels à la production agricole à la fois sur le rendement, les revenus agricoles et sur la qualité. Plusieurs mesures doivent être mises en place pour promouvoir les pollinisateurs dans les milieux agricoles dans le but de les préserver et d’assurer une production agricole durable pour ces deux cultures. / Insect pollination is essential for over 70% of crops around the world. However, the contribution of pollinators to crop production and the insects involved in crop pollination have rarely been studied. Moreover, assessments of pollinator contributions have mostly been conducted on a small scale or under simplified conditions, which do not represent the real contributions at the field scale and do not take into account possible interactions between pollinators and farming practices. The aim of this study is to quantify directly under field conditions, the contribution of pollinators in two crops frequently cultivated in Europe: oilseed rape and sunflower. Estimations are realized both at the plant and at the field scale to understand mechanisms that increase crop production. Our studies identify also these crops’ pollinators.In a first step, we quantified the contributions of pollinators to oilseed rape and sunflower yield. Oilseed rape and sunflower share a pollinator guild - the honeybee. Wild bees also increase oilseed rape yield. Pollinators increase the yield of oilseed rape by up to 35% and of sunflower by up to 40%. At the plant scale, pollinators increase pollination success and consequently the number of seeds per plant.In a second step, we compared for oilseed rape the yield and the monetary contributions of pollinators and farming practices by taking their potential interactions more accurately into account. We show that the benefits of pollinators and farming practices on yield were additive except for insecticide use, which decreased the contribution of pollinators. In addition, we show that pollinators were important contributors to the farmers’ incomes by increasing gain by 250 € per hectare while some practices were very expensive for farmers.Finally, the effect of pollinators was studied on oilseed rape seed quality - another component of crop production. We show that honeybees improve seed quality by increasing the percentage of unsaturated fatty acids in seeds and decreasing trans-saturated and saturated fatty acids. In some years, honeybees increased also the percentage of lipids per seed.We conclude, pollinators are essential for crop production by increasing both yield, monetary gain and quality. Several measures must be taken to promote pollinators in agricultural land in order to conserve them and ensure sustainable crop production for these two crops.
189

Variabilité intraspécifique des stratégies adaptatives à la sécheresse d’une graminée pérenne (Dactylis glomerata L.) : les compromis fonctionnels des traits aériens et souterrains peuvent-ils expliciter le compromis entre potentiel de croissance et survie au stress ? / Intraspecific variability of drought adaptive strategies in a perennial grass (Dactylis glomerata L.) : do functional trade-offs within above and below ground traits underpin the growth potential-stress survival trade-off?

Bristiel, Pauline 28 November 2017 (has links)
Les risques de sécheresse sévère augmentent sous l’effet du changement climatique. Mieux comprendre les stratégies adaptatives des plantes au stress hydrique est ainsi l’un des défis majeurs de la recherche écologique et agronomique. Cette thèse explore la survie à la sécheresse d’une graminée herbacée pérenne (Dactylis glomerata L.) en étudiant la variabilité intraspécifique des traits aériens et souterrains d’une quinzaine de populations natives et cultivées issues d’un gradient latitudinal allant de la Scandinavie au Maroc. Une caractérisation des populations en conditions optimales sur une année a montré une coordination phénologique des traits aériens en relation avec les limitations saisonnières de croissances liées à l’origine des populations. Le rythme de croissance au printemps et à l’automne ne discrimine pas les origines, alors que la dormance estivale des populations méditerranéennes s’oppose à la dormance hivernale des populations scandinaves. Ces résultats suggéraient l’existence d’un compromis entre survie à une déshydratation sévère (sécheresse, gel) et potentiel de croissance. Alors que ce compromis a été vérifié en été (sècheresse sévère à Montpellier) et en hiver (gel en Norvège), la survie à une déshydratation de contre-saison au printemps n’est pas corrélée au potentiel de croissance des populations. Les résultats invalident donc l’existence d’un compromis constant entre survie au stress et potentiel de croissance aérienne. Ce découplage chez le dactyle permet d’envisager la sélection artificielle, à partir de la variabilité intraspécifique existante, de variétés à la fois productives et tolérantes au stress hydrique. L’imposition d’une déshydratation édaphique sévère en pots limitant l’expansion du système racinaire a montré que les populations méditerranéennes survivent mieux que les populations tempérées ou nordiques. L’association de ces résultats avec ceux issus d’une expérimentation en longs tubes favorisant le développement potentiel des racines révèle un compromis entre les stratégies d’évitement de la déshydratation (acquisition de l’eau et maintien de la croissance) et de tolérance à la déshydratation (faible croissance et forte survie à la sécheresse) qui pourrait limiter la combinaison de stratégies adaptatives au sein d’un même phénotype. Cette thèse contribue à améliorer notre compréhension des compromis fonctionnels, peu étudiés à l’échelle intraspécifique, mais qui sous-tendent la réponse des plantes à la sécheresse. / Drought risk increases with climate change. Improving our understanding of the adaptive mechanisms of plants response to drought has thus become one of the major challenges of ecological and agronomical research. This work investigates the drought survival of a perennial herbaceous species (Dactylis glomerata L.) through the intraspecific variability of above and below ground traits expressed by fifteen native and cultivated populations originating from a large latitudinal gradient, from Scandinavia to Morocco. Population traits characterization across one year under optimal growth conditions showed phenological coordination of above ground traits associated with seasonal growth limitations according to the origins of the populations. The spring growth rhythm does not discriminate origins while the summer dormancy of Mediterranean population contrasts with the winter dormancy of Scandinavian populations. These results suggested a growth-dehydration stress survival trade-off. Although this trade-off was confirmed in summer (severe drought in Montpellier) and winter (severe frost in Norway), no correlation was found between an off-season (spring) drought stress survival and populations’ growth potential. The result invalidates the existence of a constant trade-off between stress survival and aerial growth potential. This apparent decoupling in cocksfoot could be considered to produce new cultivars with both high productivity and high drought tolerance, from existent intraspecific variability. A severe dehydration stress imposed on plants grown in short pots, limiting roots expansion, showed that Mediterranean populations survived better than temperate or Nordic populations. In association with a long tube experiment allowing full expression of roots development, this result revealed a functional trade-off between dehydration avoidance (water acquisition and growth maintenance) and dehydration tolerance (low growth and high drought survival) which could limit the combination of adaptive strategies in a single phenotype. This work contribute to improve our knowledge about functional trade-offs, few studied within species, that underpin plant response to drought stress.
190

OS AGROECOLOGISTAS DE GUARAPUAVA – PR: PERSPECTIVAS E ACESSO ÀS POLÍTICAS QUE INCORPORAM A AGROECOLOGIA / OS AGROECOLOGISTAS DE GUARAPUAVA – PR: PERSPECTIVAS E ACESSO ÀS POLÍTICAS QUE INCORPORAM A AGROECOLOGIA

Taques, Nilson Roberto 17 September 2014 (has links)
Made available in DSpace on 2017-07-21T14:42:26Z (GMT). No. of bitstreams: 1 Nilson Roberto Taques.pdf: 1951627 bytes, checksum: 905029e6e9dd3c63941956ebfd16389f (MD5) Previous issue date: 2014-09-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study is to identify the agroecologists' perspectives, setbacks and accessibility to the public policies which incorporate the foment to the agroecology in Guarapuava Pr. The research is based on qualitative exploratory data using literature review, documental analysis, semi-structured interviews and content analysis. The spatial cut corresponds to the city of Guarapuava. The theoreticalconceptual framework was founded on the theory of Gramscian Inspirational State, which supports that the agroecologic public policies appear in the context of the reevaluation of the family farming which was established in the 90' in Brazil, in response to the rural social manifestations very active in that decade. These manifestations were counter-hegemonic and were able to open political opportunities in the State bureaucratic structure. Nevertheless, these agroecologists face hegemonic groups whose roots are linked to the national state formation and to the large landed estate, and even at the present time, count on solid political representativeness. The bourgeois agribusiness integrates the hegemonic model of modernization of the Brazilian society, whereas family farming in Brazil struggles to make an alternative project viable. The agroecology present in this project is regulated by the civil society, which is opposed to the bourgeois agribusiness, and seeks the support of the state intervention specially with the implementation of public policies that enable the establishment and development of this productive practice based on economical, social and environmental sustainability. In Guarapuava, the option for agroecology is weakened by the low degree of organicity of the agroecologic social movements, and moreover, to be inserted in a political context dominated by rural oligarchies which intervene in the relationship between the local public policies and the organizations related to agroecology. / O objetivo da pesquisa é identificar as formas, impasses e perspectivas de acesso dos agroecologistas de Guarapuava – PR às políticas públicas que incorporam o fomento à agroecologia. Trata-se de pesquisa qualitativa exploratória, utilizando-se de revisão de literatura, análise documental, entrevista semiestruturada e análise de conteúdo. O recorte espacial corresponde ao município de Guarapuava. A pesquisa qualitativa baseou-se no depoimento de três agroecologistas e um representante governamental. O arcabouço teórico-conceitual fundamenta-se na teoria do Estado de inspiração gramsciana. Defende-se que as políticas públicas agroecológicas surgem no contexto de revalorização da agricultura familiar que se concretiza na década de 1990 no Brasil como resposta aos movimentos sociais rurais que se mostravam bastantes ativos naquela década. Nesse contexto, estes movimentos mostraram-se como contra-hegemônicos e conseguiram abrir espaços políticos na estrutura burocrática do Estado em consonância com seus projetos. No entanto, depararam-se com grupos hegemônicos (agronegócio burguês) que tem suas raízes ligadas à formação do estado nacional e ao latifúndio, contando ainda hoje com forte representatividade política junto ao Estado. Trazendo aspectos relevantes das forças das oligarquias rurais em nosso país; mostra-se como o agronegócio burguês integra-se ao modelo hegemônico de modernização da sociedade brasileiro e a luta da agricultura familiar no Brasil em viabilizar um projeto contra-hegemônico. Com muitos aspectos condizentes com os da agricultura familiar, a agroecologia, pautada pela sociedade civil, opõe-se ao agronegócio burguês e busca intervenção estatal, em especial com implementação de políticas públicas que possibilitem afirmação e desenvolvimento desta prática produtiva baseada na sustentabilidade econômica, social e ambiental. Conclui-se que em Guarapuava a agroecologia encontra-se fragilizada pelo grau de organicidade dos movimentos sociais agroecológicos e por estar inserida num contexto político municipal com fortes traços das oligarquias rurais bastantes presentes no cenário político, econômico e social municipal, ajudando para que prevaleça a hegemonia do agronegócio burguês e interferindo na relação entre o poder público local e as organizações ligadas a agroecologia.

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