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1
Lemky, Kim M. K. "The Amazon rainforest ecotourism industry of Napo, Ecuador." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7716.
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The two types of ecotourists have different impacts on both the local economy and the environment. The resort ecotourists are isolated to resorts. Each night is spent in the same place and tours consist of day hikes to local Indian villages and to the primary rainforest. These tourists aid the economy less than budget ecotourists because the employees that serve them are hired from outside the region and food goods for the tourists are imported into the region. In contrast, the budget ecotourists are spatially dispersed and travel each night to a new tourist camp. The budget ecotourists are essential to the economy of Pto. Misahualli. Only inhabitants of Pto. Misahualli are employed in the ecotourism industry, and all food for jungle trips is bought at local stores. Although the budget ecotourists are much more important for the local economy than resort tourists, the infrastructure of the resort ecotourists has a place in promoting the rainforest at the international level. The current ecotourism industry in Napo is sustainable within its own parameters, but the infringement of the oil industry and the small farm colonization on the primary rainforest will ultimately lead to its downfall. (Abstract shortened by UMI.)
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Jensen, Mari N. "Amazon Rainforest Greens Up in the Dry Season." College of Agriculture, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/295884.
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Labor, Felicia. "Deforestation patterns and hummingbird diversity in the Amazon rainforest." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-140513.
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In recent decades expanding land-use change has caused extensive deforestation of the tropical rainforestinducing large-scale transformation of the landscape patterns across the South American continent. Landscapechange is a modification process of the natural forest cover into fragments which generate various ecologicalimpacts. Habitat loss is identified to be a major threat to biodiversity, as it exposes species to the risk ofextinction. This study investigates 80 locations within tropical rainforest biomes to examine the landscape changewhich has occurred from 1993 – 2014. The intention is to identify the impacts of landscape fragmentation onhummingbird species diversity by spatial landscape analysis in GIS and regression modeling. The analysis foundthat there is no relationship between deforestation and reduction of hummingbird diversity. The results indicatethat hummingbird species are not particularly sensitive to landscape change as they have high resilience in regardto forest fragmentation. A potential threshold value of deforestation degree could be identified, up to whichhummingbird species richness increased, but locations subjected to over 40% fragmentation were estimated tohave lower hummingbird diversity. However, by using the spatial explicit biological data, the analysis indicatethat an extinction debt may exist in the landscape, and that future extinctions may be expected to occur in thefollowing decades as consequence of deforestation. Other factors may be as important determining variables forspecies richness: the spatial scale of the study, the habitat connectivity, hummingbird generalist tendencies.Conclusively, identification of the key factors of deforestation impacts on species diversity is essential for futureefficiency in conservation planning and sustainability of the tropical rainforest biodiversity.
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Hero, Jean-Marc, and n/a. "Predation, Palatability and the Distribution of Tadpoles in the Amazon Rainforest." Griffith University. Division of Australian Environmental Studies, 1991. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050902.155749.
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A variety of aquatic habitats with different levels of potential predators are available to larval amphibians in Central Amazon rainforest. The anuran community at Reserva Florestal Adolfo Ducke, 25 km east of Manaus, Amazonas, Brasil, was studied to determine which species have eggs and/or larvae in water and how those larvae are distributed in time and space. The temporal and spatial distribution of potential predators as well as abiotic characteristics of these waterbodies were determined simultaneously to test for correlations with the distribution of tadpoles. The distribution of tadpoles was strongly related to fish predation pressure. Several tadpole species were found only in waterbodies with high fish abundance and thus have the ability to survive with fish. Most of these tadpoles were found to be unpalatable in controlled experiments. Unpalatability is the major adaptation allowing the coexistence of tadpoles and fish and is thus a major factor affecting tadpole community composition in this system. Controlled experiments showed that fish do not eat anuran eggs while the tadpoles of Leptodacrylus knudseni and Osteocephalus taurinus ate all types of eggs offered. The percentage of anurans with aquatic oviposition was positively related to fish abundance and negatively related to the occurrence of species of tadpole that ate eggs in experiments. These findings suggest that the present patterns of anuran distribution represent an evolutionary response to predation on the eggs and larvae. Contrary to the models of Heyer et al. (1975) and Wilbur (1984), desiccation and predation-pressure were not the major factors affecting species richness within waterbodies of the RFAD rainforest. In support of the model of Heyer et al. (1975), anuran species richness was correlated with the size of the waterbody. This could be because the size of the waterbody is related to increased complexity and availability of microhabitats. The range of volumes of waterbodies was also found to directly affect species richness of the RFAD community. While predation appeared to have a limited effect on species richness of individual ponds, predation-pressure was found to have a major influence on species composition. Anuran eggs and larvae survived with specific predators by possessing particular survival-traits (e.g. unpalatability and oviposition strategies). However, survival-traits were not effective against all predators in all habitats. The distribution of different predators among ponds provides a patchy environment on a local scale (i.e. within ponds). When combined with the variety of survival-traits exhibited by the anuran species, this spatial patchiness in predation contributes towards species richness within the anuran community of the RFAD rainforest.
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Chrisney, Evan Neil. "Scatterometer Cross Calibration Using Volume Scattering Models for Amazon Rainforest Canopies." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/9103.
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Spaceborne scatterometers have measured the normalized radar cross section (RCS) of the earth's surface for several decades. Two frequencies, C- and Ku-band, have been used in designing scatterometers, such as with the Ku-band NASA Scatterometer (NSCAT) and the C-band Advanced Scatterometer (ASCAT). The scatterometer data record between C- and Ku-band has been disjoint for several decades due to the difficulties in cross calibration of sensors that operate at different frequencies and incidence angles. A model for volume scattering over the Amazon rainforest canopy that includes both the incidence angle and frequency dependence is developed to overcome this challenge in cross calibration. Several models exist for the σ0 incidence angle dependence, however, none of them are based on backscatter physics. This thesis develops a volume scattering model from a simple EM scattering model for cultural vegetation canopies and applies it to the volume scattering of the Amazon rainforest. It is shown that this model has lower variance than previously used models for the incidence angle dependence of σ0, and also enables normalization of σ0 with respect to the incidence angle. In addition, the frequency dependence of σ0 is discovered to be quite sensitive at Ku-band due to the distribution of leaf sizes in the Amazon rainforest. This may limit the accuracy of the model of the frequency dependence of σ0. Although the proposed frequency dependence model may be limited for cross calibrating between C- and Ku-band, it provides the groundwork for future studies.
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Hero, Jean-Marc. "Predation, Palatability and the Distribution of Tadpoles in the Amazon Rainforest." Thesis, Griffith University, 1991. http://hdl.handle.net/10072/366814.
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A variety of aquatic habitats with different levels of potential predators are available to larval amphibians in Central Amazon rainforest. The anuran community at Reserva Florestal Adolfo Ducke, 25 km east of Manaus, Amazonas, Brasil, was studied to determine which species have eggs and/or larvae in water and how those larvae are distributed in time and space. The temporal and spatial distribution of potential predators as well as abiotic characteristics of these waterbodies were determined simultaneously to test for correlations with the distribution of tadpoles. The distribution of tadpoles was strongly related to fish predation pressure. Several tadpole species were found only in waterbodies with high fish abundance and thus have the ability to survive with fish. Most of these tadpoles were found to be unpalatable in controlled experiments. Unpalatability is the major adaptation allowing the coexistence of tadpoles and fish and is thus a major factor affecting tadpole community composition in this system. Controlled experiments showed that fish do not eat anuran eggs while the tadpoles of Leptodacrylus knudseni and Osteocephalus taurinus ate all types of eggs offered. The percentage of anurans with aquatic oviposition was positively related to fish abundance and negatively related to the occurrence of species of tadpole that ate eggs in experiments. These findings suggest that the present patterns of anuran distribution represent an evolutionary response to predation on the eggs and larvae. Contrary to the models of Heyer et al. (1975) and Wilbur (1984), desiccation and predation-pressure were not the major factors affecting species richness within waterbodies of the RFAD rainforest. In support of the model of Heyer et al. (1975), anuran species richness was correlated with the size of the waterbody. This could be because the size of the waterbody is related to increased complexity and availability of microhabitats. The range of volumes of waterbodies was also found to directly affect species richness of the RFAD community. While predation appeared to have a limited effect on species richness of individual ponds, predation-pressure was found to have a major influence on species composition. Anuran eggs and larvae survived with specific predators by possessing particular survival-traits (e.g. unpalatability and oviposition strategies). However, survival-traits were not effective against all predators in all habitats. The distribution of different predators among ponds provides a patchy environment on a local scale (i.e. within ponds). When combined with the variety of survival-traits exhibited by the anuran species, this spatial patchiness in predation contributes towards species richness within the anuran community of the RFAD rainforest.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Division of Australian Environmental Studies
Science, Environment, Engineering and Technology
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Portela, Rosimeiry G. "Integrated ecological economic modeling of ecosystem services from the Brazilian Amazon rainforest." College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/1958.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2004.Thesis research directed by: Marine-Estuarine-Environmental Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Zhouri, AndreÌa. "Trees and people : an anthropology of British campaigners for the Amazon Rainforest." Thesis, University of Essex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265187.
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Cohalan, Jean-Michel. "River trading in the Peruvian Amazon : market access and rural livelihoods among rainforest peoples." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111508.
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Access to markets is increasingly regarded in development circles as a critical factor in determining livelihood choices in peasant economies. In the northeastern Peruvian Amazon, a multitude of river transporters and market intermediaries based in the central city of Iquitos provide essential services and market opportunities for remote peasant producers across the region. Using a multi-scalar, multi-method approach involving extensive fieldwork in the Peruvian Amazon, this research (re)assesses the meanings and implications of "remoteness" and "connectedness" for rural peasants. At the regional scale, I examine the functional heterogeneity of river trading networks and marketing agents. Given the high-risk/high-transaction-cost environment, river trading is found to be expensive for producers and traders alike. High costs are exacerbated by the low gross returns of rural production (mainly food and natural building materials). Thin or missing markets for credit, labour, land and insurance increase the hardships associated with limited access to product markets. Regional findings are complemented with a comparative livelihoods analysis in two remote communities of the Alto Tigre River that benefit from differential access to oil-labour. My study reveals that differential access to labour has significant impacts on the livelihood strategies of working households. However, given limited access to external markets, cash-income from oil-labour is found to offer limited opportunities for growth. In sum, the research proposes insights for advancing the debate on livelihoods and poverty in the Peruvian Amazon.
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Yao, Yitong. "Impacts of drought on biomass and carbon fluxes in the Amazon rainforest : a modeling approach." Electronic Thesis or Diss., université Paris-Saclay, 2022. http://www.theses.fr/2022UPASJ010.
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Les sécheresses ont eu un impact récurrent sur les forêts tropicales amazoniennes, amenuisant la capacité de puits de carbone de la biomasse forestière. La plupart des modèles globaux de surface terrestre utilisés pour les évaluations du budget mondial du carbone et les projections climatiques futures, n'intègrent pas la mortalité des arbres induite par la sécheresse. Leurs prévisions de la dynamique de la biomasse sont donc sujettes à de grandes incertitudes. Les faiblesses des modèlesglobaux sont liés à : (1) l’absence de la représentation explicite du transport hydraulique; (2) le manque d'équations basées sur les processus à travers la description de la façon dont une altération du système de transport hydraulique des arbres conduit à la mortalité ; (3) le manque de représentation de la mortalité à travers les tailles des arbres. Tout d'abord, j'ai implémenté une architecture hydraulique mécaniste qui a été conçue par E. Joetzjer, et un module de mortalité des arbres que j'ai conçu dans l'ORCHIDEE-CAN-NHA. Notre modèle a produit des taux annuels de mortalité des arbres comparables à ceux observés et a capturé la dynamique de la biomasse. Ce travail fournit une base pour des recherches ultérieures sur l'assimilationdes données d'observation expérimentales afin de paramétrer la mortalité des arbres induite par la défaillance hydraulique.Deuxièmement, j'ai appliqué ORCHIDEE-CAN-NHA sur la forêt tropicale intacte de l'Amazonie. Le modèle a reproduit la sensibilité à la sécheresse de la croissance et de la mortalité de la biomasse aérienne (AGB) observée sur des réseaux de placettes d'inventaire forestier dans les forêts intactes d'Amazonie pour les deux récentes méga-sécheresses de 2005 et 2010. Dans le modèle, même si le changement climatique, avec des sécheresses devenant plus sévères, a eu tendance à intensifier la mortalité des arbres, l'augmentation de la concentration de CO2 a contribué à atténuer la perte de carbone due à la mortalité en supprimant la transpiration. Enfin, j'ai utilisé le modèle ORCHIDEE-CAN-NHA afin de simuler le futur du stockage ducarbone dans la biomasse en Amazonie. La plupart des modèles climatiques (ISIMIP-2) projettent néanmoins de manière cohérente une tendance plus sèche dans le nord-est de l'Amazonie. La simulation forcée par le modèle climatique HadGEM dans le scénario RCP8.5 montre un assèchement plus prononcé dans l'est et le nord-est de l'Amazonie, avec un point d'intersection où le puits de carbone se transforme en source de carbone dans le bouclier guyanais et le centre-est de l'Amazonie, au milieu du 21e siècle. Cette étude permet de prédire l'évolution future de la dynamique de la biomasse de la forêtamazonienne avec un modèle amélioré basé sur les processus, capable de reproduire la mortalité induitepar le changement climatique. Dans les sections conclusion et perspectives, des développements futurs et des priorités de recherche sont proposés, qui amélioreraient la fiabilité et les performances du modèle basé sur les processus présentés dans cette thèse, permettant de mieux capturer les mécanismes qui contrôlent l'évolution de la dynamique de la biomasse forestière face à des risques de sécheresse plus fréquentsDroughts have recurrently impacted the Amazon rainforests, undermining the forest biomass carbon sink capacity due to a quicker increase of biomass mortality compared to growth. Most global land surface models used for assessments of the Global Carbon Budget and future climate projections have not incorporated drought-induced tree mortality. Their prediction of biomass dynamics are therefore subject to large uncertainties, as a result of (1) lack of explicit simulation of hydraulic transportin the continuum from soil to leaves; (2) lack of process-based equations connecting the impairment of the hydraulic transport system of trees to mortality; (3) lack of representation of mortality across trees sizes. To address these critical research gaps, I improved plant hydraulic representation in ORCHIDEECAN. This model was re-calibrated and evaluated over rainforests in Amazon basin, and applied to simulate the future evolution of biomass dynamics facing droughts. Firstly, I implemented a mechanistic hydraulic architecture that was designed by E. Joetzjer, and a hydraulic-failure related tree mortality module that I designed into ORCHIDEE-CAN. The model was calibrated against the world’s longest running drought manipulation experiment of Caxiuana in the eastern Amazon. Our model produced comparable annual tree mortality rates than the observation andcaptured biomass dynamics. This work provides a basis for further research in assimilating experimental observation data to parameterize the hydraulic failure induced tree mortality. Secondly, I applied ORCHIDEE-CAN-NHA over the Amazon intact rainforest. The model reproduced the drought sensitivity of aboveground biomass (AGB) growth and mortality observed atnetworks of forest inventory plots across Amazon intact forests for the two recent mega-droughts of 2005 and 2010. We predicted a more negative sensitivity of the net biomass carbon sink to water deficits for the recent 2015/16 El Nino, which was the most severe drought in the historical record. In the model, even if climate change with droughts becoming more severe tended to intensify tree mortality, increased CO2 concentration contributed to attenuate the C loss due to mortality by suppressing transpiration.Lastly, I used the ORCHIDEE-CAN-NHA model for future simulations of biomass carbondynamics. Most climate models (ISIMIP2 program) consistently predict a drier trend in northeastern Amazon. The simulation forced by the HadGEM climate model in the RCP8.5 scenario shows the most pronounced drying in eastern and northeastern Amazon, with a cross-over point at which the carbon sink turned to a carbon source in the Guiana Shield and East-central Amazon in the middle of the 21st century. This study sheds light on predicting the future evolution of Amazon rainforest biomass dynamics with an improved process-based model able to reproduce climate-change induced mortality.In the conclusion and outlook sections, future developments and research priorities are proposed, which would improve the reliability and performances of the process-based model presented in this dissertation, allowing to better capture mechanisms that control the evolution of forest biomass dynamics in the face of more frequent drought risks
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Berglund, Amanda. "Community-based conservation in Peruvian Amazon. Attempts to save the red uakari of Loreto." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-303504.
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Abstract. In Peru, the population of a very rare monkey species called the red uakari (Cacajao calvus ucayalii) lives in the Amazon rainforest in an area called Loreto. The natural resources of Loreto have been exploited due to large anthropogenic pressure which has affected the biodiversity. This thesis focuses on two areas that are now protected; one conservation concession and one community-based conservation reserve, each led by two biologists and researchers. The theory of the tragedy of the commons – a concept first described by Garrett Hardin in an article in the scientific journal Science in 1968 – will be taken into consideration and analysed when studying the common gains to protect the forest, as well as the over usage of resources. This thesis investigates in a qualitative way the risks of overexploiting the rainforest and the actions taken to preserve it, and hence saving the red uakari from becoming extinct. A combination of semi-structured interviews with the two biologists and content analysis of some of their work, amongst others, will assist in the outcome of this thesis, which is intended to be used for future protection of inhabited lands in rainforests that run the risk of being overexploited due to external commercial interests. The supposition of my study was to get a better understanding of community-based action to protect a specific space in an area that is under a great deal of external pressure and it shows that collective action and involvement of local community often has positive outcome.
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Moreau, Marie-Annick 1976. "Rainforest fisheries : regional organization and household participation in the aquarium fish trade of the Peruvian Amazon." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81364.
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Conservation of the world's biodiversity is increasingly viewed as a development problem, requiring the alleviation of poverty together with the promotion of alternative livelihoods in resource-reliant communities. To be successful, such efforts must recognize the underlying logic of resource-users' livelihood choices. This study uses the activity of aquarium fish extraction in the Peruvian Amazon as a case study through which to examine the role that physical and non-physical assets (primarily knowledge) might play in determining households' participation patterns. An initial survey of the regional trade, undertaken through interviews with trade participants (n = 38) and analysis of government documents, revealed a large, valuable and complex industry. Data gathered through surveys among households in two proximate fishing villages (n = 37) indicated large inter- and intra-village variation in trade participation. Households that specialize in the activity tend to be young, and rich in nonphysical assets of knowledge and social capital.
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Venancio, Bárbara Rocha [UNESP]. "Chain of custody control of ipe timber (Handroanthus sp.) from the Amazon rainforest, using DNA fingerprinting." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/150808.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A presente dissertação de mestrado é composta por uma seção introdutória, seguida de uma revisão da literatura a qual antecede os três capítulos subsequentes. O primeiro capítulo aborda um conjunto de revisões de conhecimentos científicos contemporâneos sobre os efeitos da exploração madeireira em florestas tropicais e as práticas madeireiras utilizadas no Brasil, quais têm se demonstrado insuficientes para garantir a sustentabilidade tanto na produção genética quanto na produção madeireira. O segundo capítulo é um “primer note” descrevendo a identificação de 402 loci putativos (polimorfismos de nucleotídeo único – SNPs, inserções / deleções - INDELs) para Ipe (Handroanthus sp.), destinado à estudos de genética de populações, filogeografia e DNA fingerprinting. O último capítulo discute a viabilidade de DNA fingerprinting para espécies do gênero Handroanthus. Esse traz a análise da diversidade genética, diferenciação genética de populações de Handroanthus sp., bem como entre os países de origem das amostras, análises de auto atribuição de genótipos e testes de atribuição de madeira ao local de origem.
The present master dissertation is composed by an introductory section, followed by a review of literature, which prefaces the three subsequent chapters. The first chapter of this dissertation is a review assembly contemporary scientific knowledge about the effects of the forest logging in tropical rainforests and the actual logging practices used in Brazil, which seems insufficient to ensure sustainability in both genetic and timber production aspects. The second chapter is a primer note describing the identification of 402 putative loci (single nucleotide polymorphisms –SNPs; and insertion/deletions- INDELs) for Ipe (Handroanthus sp.), intended to help population genetics, phylogeography and DNA fingerprinting studies. The last chapter discuss the feasibility of DNA fingerprinting for Handroanthus species. It brings genetic diversity analysis, genetic differentiation of Handroanthus sp. sample-populations, as well as among countries, self-assignment and timber assignment tests analysis.
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Venancio, Bárbara Rocha. "Chain of custody control of ipe timber (Handroanthus sp.) from the Amazon rainforest, using DNA fingerprinting /." Ilha Solteira, 2017. http://hdl.handle.net/11449/150808.
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Orientador: Alexandre Magno SebbennResumo: A presente dissertação de mestrado é composta por uma seção introdutória, seguida de uma revisão da literatura a qual antecede os três capítulos subsequentes. O primeiro capítulo aborda um conjunto de revisões de conhecimentos científicos contemporâneos sobre os efeitos da exploração madeireira em florestas tropicais e as práticas madeireiras utilizadas no Brasil, quais têm se demonstrado insuficientes para garantir a sustentabilidade tanto na produção genética quanto na produção madeireira. O segundo capítulo é um “primer note” descrevendo a identificação de 402 loci putativos (polimorfismos de nucleotídeo único – SNPs, inserções / deleções - INDELs) para Ipe (Handroanthus sp.), destinado à estudos de genética de populações, filogeografia e DNA fingerprinting. O último capítulo discute a viabilidade de DNA fingerprinting para espécies do gênero Handroanthus. Esse traz a análise da diversidade genética, diferenciação genética de populações de Handroanthus sp., bem como entre os países de origem das amostras, análises de auto atribuição de genótipos e testes de atribuição de madeira ao local de origem.
Mestre
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Valach, Amy C. "Volatile organic compound fluxes and mixing ratios in two contrasting atmospheric environments : London and the Amazon rainforest." Thesis, Lancaster University, 2015. http://eprints.lancs.ac.uk/76898/.
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Volatile organic compounds (VOCs) from biogenic and anthropogenic sources are important constituents of the atmosphere with effects on air quality and climate. Current uncertainties in measurements and models relate to their roles in tropospheric ozone and secondary organic aerosol formation, yet there have been few measurements of their fluxes from contrasting chemical environments. Additional measurements with greater spatial and temporal resolutions are required to constrain uncertainties in atmospheric chemistry and climate models. This thesis presents long-term measurements of VOC fluxes and concentrations in two contrasting environments: central London and the Brazilian Amazon. VOC concentrations were quantified by proton transfer reaction-mass spectrometry and fluxes were calculated using the virtual disjunct eddy covariance method over a period of several months at sites in central London and the Amazon rainforest. In central London, traffic was found to be the main source of aromatic compounds. Oxygenated compounds and isoprene showed strong correlations with light and temperature, suggesting biogenic, evaporative, or secondary atmospheric origins. The seven VOCs measured in central London had a five-month average total emission rate of 1.4 mg m-2 h-1. Comparisons with local and national emission inventories showed that modelled emissions were largely underestimated. Measurements of isoprene and monoterpenes at the remote ZF2 site in the Amazon rainforest showed an 11-month average total emission rate of 2.7 mg m-2 h-1 with considerable seasonal variation, which could not be accurately reproduced using the light and temperature based MEGAN algorithms. This thesis presents the first long-term VOC flux measurements providing information at high temporal resolutions on seasonal variability at an urban site and a pristine tropical forest site. They confirm that the Amazon rainforest is an extremely strong source of reactive carbon to the Earth’s atmosphere exceeding emissions from a developed megacity, such as London, per unit area.
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Ciemer, Catrin. "Complex systems analysis of changing rainfall regimes in South America and their implications for the Amazon rainforest." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19896.
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Das Ziel dieser Arbeit ist die systematische Untersuchung der Auswirkungen von Änderungen in der Niederschlagshäufigkeit und -menge im Amazonas sowie eine Prognose der zukünftigen Entwicklung des Regenwaldes unter den sich ändernden Bedingungen im Rahmen des Klimawandels. Die in dieser Arbeit durchgeführten Untersuchungen der Niederschlagskorrelationsmuster des südamerikanischen Monsuns basieren auf der Theorie komplexer Netzwerke und offenbaren beispielsweise den Übergang von einem geordneten zu einem ungeordneten System zu Beginn des Monsuns. Die Erweiterung der verwendeten Methoden hin zu mehrschichtigen Netzwerken wird anschließend zur Untersuchung der Ursache von Dürren im zentralen Amazonasgebiet verwendet. Ein bivariates Netzwerk aus Niederschlagsdaten und atlantischen Meeresoberflächentemperaturen zeigt, dass bestimmte Meeresregionen im tropischen Atlantik den Niederschlag im zentralen Amazonas stark beeinflussen. Die Ergebnisse dieser Arbeit zeigen, dass einer Dürre in der Regel die Entstehung eines klimatischen Dipols der Meeresoberflächentemperaturen zwischen den identifizierten Ozeanregionen vorausgeht. Aufbauend auf diesen Ergebnissen wird in dieser Arbeit erstmalig ein Frühwarnsystem für Dürren im Amazonas vorgestellt. Der Untersuchung des Einflusses von Niederschlagsvariabilität auf die Vegetation wird eine Potentiallandschaft aus Niederschlags- und Baumbedeckungsdaten im Amazonas zugrunde gelegt. Die vorliegende Studie zeigt, dass eine direkte Abhängigkeit zwischen der lokalen, langfristigen Niederschlagsvariabilität und der Resilienz des Waldes besteht. Dies bedeutet, dass stärkere jährliche Niederschlagsvariabilität zu einem Trainingseffekt der tropischen Vegetation führen kann. Bedenkt man außerdem, dass es in Zukunft im zentralen Amazonas mehr Dürren geben soll, kann es entscheidend sein, ob die Vegetation einer Region zuvor Erfahrung mit starker Niederschlagsvariabilität gemacht hat und dementsprechend angepasst ist. Um nicht nur lokale, sondern auch globale Einflüsse zu berücksichtigen, wird zum einen der Effekt einer sich verlangsamenden thermohalinen Zirkulation durch Klimaerwärmung und zum anderen der direkte Einfluss der Klimaerwärmung auf denn zentralen Amazonas Regenwald untersucht. Die Studie zeigt, dass beide Ereignisse gegensätzliche und somit sich ausgleichende Einflüsse auf die Vegetation im Amazonasgebiet haben können. Der Regenwald könnte somit stabil in Bezug auf den Klimawandel sein. Die vorliegende Dissertation Arbeit leistet auf der Basis von neu entwickelten Methoden einen wesentlichen Beitrag, um die Kenntnisse der betrachteten klimatischen und ökologischen Systeme zu vertiefen.This thesis investigates the impact of changes in frequency and amount of precipitation in the Amazon rainforest and analyzes its development under the changing conditions due to global warming. In this context, complex network theory is utilized to investigate the South American monsoon system. The precipitation correlation structure reveals hidden features of the system, such as the transition from a disordered to an ordered monsoon system. Further developing existing network methods towards multilayer network tools allows for the investigation of the root causes for droughts in the central Amazon basin. By using a bivariate network between monthly precipitation in the central Amazon and Atlantic sea surface temperatures, distinct oceanic regions are identified to have a strong influence on central Amazonian precipitation. The formation of a climatological dipole between the northern and southern tropical Atlantic sea surface temperatures is found to precede droughts. As a result, this study is the first to give an early warning for droughts in the Amazon. To investigate the influence of rainfall variability on vegetation, a potential landscape is constructed from precipitation and Amazonian tree cover data. The resilience of the forest is found to directly depend on the local rainfall variability in the long-term past, thereby reflecting a vegetational training effect under specific environmental conditions. Considering climate change projections, this effect could be decisive for the future survival of the present rainforest vegetation state. In order to cover long-term influences of global warming, this thesis additionally investigates the effects of a slowing down of the Atlantic meridional overturning circulation and the direct influence of global warming on the southern Amazon rainforest.. It is revealed that these effects, although caused by global warming, have competitive impacts on precipitation in the Amazon basin, with a stabilizing effect of an Atlantic meridional overturning circulation slowdown on the Amazon rainforest. This dissertation provides newly developed, as well as adjusted methods to enhance our understanding of the considered climatological and vegetational systems. Together, they provide the basic tools for a further investigation of these complex systems.
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Leppla, Denis [Verfasser]. "Comprehensive Study of Secondary Organic Aerosol Particles from the Amazon Rainforest by High-Resolution Mass Spectrometry / Denis Leppla." Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2021. http://d-nb.info/1232912743/34.
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Santos, Fernando Cavalcante dos. "Biomass burning and natural emissions in the brazilian Amazon rainforest: impact on the oxidative capacity of the atmosphere." Instituto Nacional de Pesquisas Espaciais (INPE), 2017. http://urlib.net/sid.inpe.br/mtc-m21b/2017/05.29.14.21.
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Emitted by vegetation, isoprene (2-methyl-1,3-butadiene) is the most abundant non-methane hydrocarbons, with an annual global emission calculated ranging from 440 to 660Tg carbon, depending on the driving variables like temperature, solar radiation, leaf area index and plant functional type. It is estimated, for example, that the natural compounds like isoprene and terpenes present in the troposphere are about 90\% and 50\%, respectively, removed from the atmosphere by oxidation performed by hydroxyl radical (OH). Furthermore, the oxidation products of isoprene may contribute to secondary organic aerosol (SOA) formation, affecting the climate and altering the properties and lifetimes of clouds. Considering the importance of these emissions and the hydroxyl radical reaction in the atmosphere, the SAMBBA (South American Biomass Burning Analysis) experiment, which occurred during the dry season (September 2012) in the Amazon Rainforest, provided information about the chemical composition of the atmosphere through airborne observations. Although primarily focused on biomass burning flights, the SAMBBA project carried out other flights providing indirect oxidative capacity data in different environments: natural emission dominated flights and biomass-burning flights with fresh plumes and aged plumes. In this study, we evaluate the oxidative capacity of the Amazon rainforest in different environments, both for the unpolluted and biomass-burning disturbed atmosphere using the ratio [MVK + MACR]/[Isoprene]. Beyond that, we propose an improvement on the formulation of indirect OH density calculation, using the photochemical aging [O$_{3}$]/[CO] as a parameter. Using a synergistic approach, balancing numerical modeling and direct observations, the numerical model BRAMS was coupled to MEGAN emission model to get a better result for isoprene and OH in the atmosphere, representing the observations during SAMBBA field campaign. In relation to OH estimation, we observed an improvement in the concentration values using the modified sequential reaction model, for both biomass burning regimes and background environment. We also detected a long-range transport events of O$_{3}$ during SAMBBA experiment, considering the high levels of O3 in aged plumes at high altitudes (5,500 6,500 m), and the detection of an O$_{3}$ inflow in the Amazon basin from Africa. These findings support the importance of long-range transport events as a source of O$_{3}$ into the troposphere in the Amazon basin, which could even alter the atmospheric composition within the planetary boundary layer and alter the oxidative capacity in the region. The model results showed a reasonable agreement for isoprene concentration, although more investigation needed for the OH simulation.Emitido pela vegetação, o isopreno (2-metil-1,3-butadieno) é o hidrocarboneto não-metânico mais abundante, com uma emissão global anual calculada entre 440 e 660Tg de carbono, dependendo de variáveis como temperatura, radiação solar, índice de área foliar e tipo funcional da planta. Estima-se, por exemplo, que os compostos naturais como isopreno e terpenos presentes na troposfera são cerca de 90\% e 50\%, respectivamente, removidos da atmosfera por oxidação realizada por radical hidroxila (OH). Além disso, os produtos de oxidação do isopreno podem contribuir para a formação de aerossóis orgânicos secundários (AOS), afetando o clima e alterando as propriedades e o ciclo hidrológico das nuvens. Considerando a importância dessas emissões e a reação do radical hidroxila na atmosfera, o experimento SAMBBA (do inglês, South American Biomass Burning Analysis), que ocorreu durante a estação seca (setembro de 2012) na Floresta Amazônica, forneceu informações sobre a composição química da atmosfera através de observações aéreas. Embora focado principalmente nos voos ocorridos durante a queima de biomassa, o projeto SAMBBA realizou outros voos que forneceram dados indiretos de capacidade oxidativa em diferentes ambientes: voos dominados por emissão natural e voos com queima de biomassa com plumas frescas e envelhecidas. Neste estudo, avaliamos a capacidade oxidativa da floresta amazônica em diferentes ambientes, tanto para a atmosfera não poluída quanto para atmosfera perturbada pela queima de biomassa usando a razão [MVK + MACR] / [Isoprene]. Além disso, propomos uma melhoria na formulação do cálculo da densidade indireta de OH, usando o envelhecimento fotoquímico [O$_{3}$] / [CO] como parâmetro. Usando uma abordagem sinérgica, balanceando modelagem numérica e observações diretas, o modelo numérico BRAMS foi acoplado ao modelo de emissão MEGAN para obter um melhor resultado para isopreno e OH na atmosfera, representando as observações durante a campanha do SAMBBA. Em relação à estimativa de OH, observamos uma melhora nos valores de concentração usando o modelo de reação sequencial modificada, tanto para os regimes de queima de biomassa quanto para região pristina. Também detectamos eventos de transporte de longo alcance de O3 durante o experimento SAMBBA, considerando os altos níveis de O$_{3}$ em plumas envelhecidas em altitudes elevadas (5.500 - 6.500 m) e a detecção de um influxo de O$_{3}$ na bacia amazônica proveniente da África. Essas descobertas sustentam a importância dos eventos de transporte de longo alcance como fonte de O$_{3}$ na troposfera da bacia amazônica, o que poderia até alterar a composição atmosférica dentro da camada limite planetária e alterar a capacidade oxidativa da região. Os resultados do modelo mostraram uma correlação razoável para a concentração de isopreno, embora fosse necessária mais investigação para a simulação de OH.
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Kjellin, Sofia. "Political leaders' motives to action : An analysis of Jair Bolsonaro's and Emmanuel Macron's motives in the Amazon rainforest fires." Thesis, Linnéuniversitetet, Institutionen för statsvetenskap (ST), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-91153.
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This study seeks to explain political leaders' motives to action, by studying how Jair Bolsonaro and Emmanuel Macron have acted in the matter of the fires in the Amazon rainforest. It is assumed that while political leaders may try to act rationally, they are influenced by psychological factors in terms of educational background and style. The theories of rational choice and political psychology are therefore used and integrated to explain their motives. The method used in the paper is a comparative qualitative content analysis, in which various statements and speeches made by the Presidents are read and analyzed. The results of the thesis show that for Bolsonaro, the Amazon fires is an internal matter and should be handled by the Amazonian countries. He seems to be seeking to achieve national goals, while being influenced by his conservative educational background. Macron indicates that the Amazon is an issue for the international community and that it is of major importance for the whole world. He appears to be seeking international goals, while being influenced by his liberal educational background. The assumption that political leaders' style influence their motives to action is not supported.
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Jessen, Rosa Raquel. "Behavior and Ecology of Neotropical Tree Squirrels in Seasonally Flooded Forests in the Peruvian Amazon." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/293536.
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Tree squirrels play an important role in the maintenance of forest ecosystems by functioning as seed and fungal spore dispersers, forest regenerators, and prey for forest predators. The highest species richness for tree squirrels occurs in tropical forests and these species are also the least studied. We conducted distance sampling to estimate population density, measured habitat variables to investigate forest characteristics that influence habitat selection and feeding site selection at three different scales, and conducted observations to obtain knowledge about activity pattern and behavior of Neotropical pygmy squirrels and Amazon red squirrels in the Peruvian Amazon. Density of Neotropical pygmy squirrels was 0.10 and 0.14 individuals/ha for 2009 and 2010. Activity peaked in early morning, squirrels were found mainly in the canopy but never on the ground, and frequency of behaviors differed by time and story level. Neotropical pygmy squirrels used mainly high and low restinga and areas that had more large trees. Squirrels also used species of trees disproportionately to availability. Neotropical pygmy squirrels seem to be associated with features related to mature forests. Amazon red squirrels use mainly high and low restinga and selected Astrocaryum and Attalea palm trees that were taller and larger as foraging sites compared to random locations. Amazon red squirrels used all vertical strata of the forest and the main behaviors observed were travel and forage. Behaviors were similar among time periods but differed in frequency by vertical strata. Although Amazon red squirrels used vegetation communities differently than their availability and selected for tree characteristics, they did not select for site characteristics and this is different from other tree squirrel species. We also conducted surveys during a wet and a dry year to investigate and estimate diversity of diurnal mammals. We assessed the vertical strata of the forest to determine if diversity index varied by story level, and estimated alpha, beta, and gamma diversity. Overall mammal diversity did not differ between wet and dry years. Diversity index differed by story level between years, but was the highest in the canopy for both years. Alpha diversity was higher in the dry year, and gamma and beta diversity were higher in the wet year. Frequency of sightings of species was influenced by time of day and varied by story level. Protection of continuous, mature forests with large canopies has important conservation implications as these areas most likely protect the greatest diversity of mammals while also providing shelter and food for other taxa.
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da, Motta Amadeu Flavia Regina. "Reflecting on capabilities and interactions between designers and local producers through the materiality of the rubber from the Amazon rainforest." Thesis, University of the Arts London, 2015. http://ualresearchonline.arts.ac.uk/12018/.
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Designers have recently become increasingly involved with small-scale producer communities around the world, mostly in the southern hemisphere, and this increase has highlighted the significance of these encounters in the creation of economic and social opportunities for those peoples. This study identifies that, however, these encounters present challenges and imply ethical responsibilities that current design methodologies fail to embrace in their long-term goals. This research investigates the interaction between designers visiting local producers whose livelihood is deeply dependent not just on the natural environment and their local culture but also on the process of fabrication. This thesis proposes a new methodology to guide designers and producers through a reflective process of social change in producer communities. This methodology derives from a combination of activity theory and the capability approach to wellbeing applied within design and producer community practices. The aim is to support a dialogical and holistic design approach to this kind of cooperation, as well as to endorse research and professional practice in the field of design for social change. This research seeks to break new ground by generating perspectives that support both designers and local producers in tackling and resolving issues of individual and collective wellbeing. The research draws on interviews with designers working with local producers in different countries. In addition, the author presents her own experiences of researching and working with Amazon rainforest rubber-tapping communities which have adopted new production methods in order to acquire new capabilities and help conserve their environment. Two case studies illustrate the reflective methodology applied to the designer and producer interactions within social innovation and entrepreneurship. But it is fundamentally the materiality of the rubber, and the revelation of the interdependences within and without the locality, that form the framework of this thesis.
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Stark, Scott C. "On the Mechanistic Connection of Forest Canopy Structure with Productivity and Demography in the Amazon." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/265347.
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Canopy structure has long been thought to influence the productivity and ecological dynamics of tropical forests by altering the availability of light to leaves. Theories and methods that can connect detailed quantitative observations of canopy structure with forest dynamics, however, have been lacking. There is urgent need to resolve this uncertainty because human-caused climate change may alter canopy structure and function in the Amazon. This work addresses this problem by, first, developing methods based on LiDAR remote sensing of fine-scale structural variation to predict the spatial structure of leaf area and light in forest canopies of the central Amazon (Appendices B&C). I show that LiDAR-based leaf area and light estimates can be used to predict the productivity of tree size groups and one-hectare forest plots--as well as differences between 2 sites separated by 500km (App. B). Sites also differed in canopy structure and the distribution of tree frequencies over size (size or diameter distribution). A model based on tree architecture, however, was able to connect observed differences in canopy architecture with size distributions to predict plot and site differences (App. D). This model showed that tree architecture is plastic in different light environments. While plasticity may increase light absorption, the smallest size groups appeared light limited. Absorption over size groups in one site, but not the other, agreed with the hypothesis of energetic equivalence across size structure. Ultimately, the performance of individual trees of different sizes in different canopy environments links forest demography with canopy structure and ecosystem function--I present a study aimed at improving tests of individual level theories for the role of light dependence in tree growth (App. A). Together, this work quantitatively connects canopy structure with forest carbon dynamics and demographic structure and further develops LiDAR as premier tool for studying forest ecological dynamics. Assessing variation in biomass growth and demographic structure over tropical landscapes with remote sensing will improve understanding of ecosystem function and the role of the Amazon in global Carbon dynamics.
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Woebbe, Eric. "Survey of a Neotropical anuran assemblage (Pacaya-Samiria Reserve, Peru)." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1493154522047725.
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Kuahara, Tomita Chris. "Creación de una ONG como alternativa de gestión de impactos sociales. Caso : Empresa Amazon Rainforest Conservation en la Reserva Nacional Pacaya Samiria." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2011. http://tesis.pucp.edu.pe/repositorio/handle/123456789/1383.
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El presente documento describe el proceso de construcción de una ONG que contribuye a
gestionar los posibles impactos sociales y complemente las prácticas de responsabilidad
social del econegocio Amazon Rainforest Conservation (ARC) en la zona de
amortiguamiento de la Reserva Nacional Pacaya Samiria. El cual venderá servicios
ambientales en una concesión destinada a la conservación de 81 645 hectáreas con 15
comunidades amazónicas adyacentes.
Si bien la creación de una organización social no es la única alternativa válida, es una
propuesta pertinente y ventajosa; dado que le permite a ARC tomar decisiones de manera
rápida y flexible, posibilita que la empresa reciba beneficios fiscales, mantiene visible a
ARC en las comunidades, y en el caso de que los costos de los proyectos sociales se
incrementen o se deseen elaborar más proyectos, ésta podría participar en fondos
concursables para obtener financiamiento y/o ofrecer consultorías a otras empresas del
rubro.
A lo largo del trabajo se utilizaron y adaptaron algunas herramientas de gestión para
organizar y facilitar el proceso de análisis estratégico y aplicación. De esta manera se
plantea no sólo la viabilidad de la ONG sino su programación estratégica, su descripción
y su adaptación al escenario; el cual es determinado por las leyes y políticas nacionales,
los grupos de interés, la economía, cultura y medio ambiente. Todo en búsqueda de una
organización sostenible y eficiente que le sea útil a la empresa y al mismo tiempo
contribuya al desarrollo sostenible de las comunidades amazónicas vinculadas a la
concesión de ARC.Tesis
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Boulton, Christopher Andrew. "Early warning signals of environmental tipping points." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/18568.
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This thesis examines how early warning signals perform when tested on climate systems thought to exhibit future tipping point behaviour. A tipping point in a dynamical system is a large and sudden change to the state of the system, usually caused by changes in external forcing. This is due to the state the system occupies becoming unstable, causing the system to settle to a new stable state. In many cases, there is a degree of irreversibility once the tipping point has been passed, preventing the system from reverting back to its original state without a large reversal in forcing. Passing tipping points in climate systems, such as the Amazon rainforest or the Atlantic Meridional Overturning Circulation, is particularly dangerous as the effects of this will be globally felt. Fortunately there is potential for early warning signals, designed to warn that the system is approaching a tipping point. Generally, these early warning signals are based on analysis of the time series of the system, such as searching for ‘critical slowing down’, usually estimated by an increasing lag-1 autocorrelation (AR(1)). The idea here is that as a system’s state becomes less stable, it will start to react more sluggishly to short term perturbations. While early warning signals have been tested extensively in simple models and on palaeoclimate data, there has been very little research into how these behave in complex models and observed data. Here, early warning signals are tested on climate systems that show tipping point behaviour in general circulation models. Furthermore, it examines why early warning signals might fail in certain cases and provides prospect for more ‘system specific indicators’ based on properties of individual tipping elements. The thesis also examines how slowing down in a system might affect ecosystems that are being driven by it.
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Paulo, Carla Moura de. "As políticas de biodiversidade e de mudanças climáticas: (des) articulações e reflexos sobre o mosaico de conservação do Cristalino/ MT." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/106/106132/tde-13072016-110405/.
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As modificações do clima se apresentam como um dos maiores desafios da sociedade contemporânea, principalmente no que se refere aos seus efeitos no meio natural e na biodiversidade. Os riscos das alterações climáticas ainda não são totalmente conhecidos, e suas consequências para a diversidade biológica estão sendo descobertas no momento atual. Porém, seus impactos vão além das modificações no ambiente natural e se refletem também nas políticas e relações mundiais. Neste sentido, o presente trabalho analisa as inter-relações entre as políticas públicas de biodiversidade e de mudanças climáticas, nas diferentes escalas de atuação. O interesse é identificar como um problema de ordem mundial se desdobra em âmbito local. Para isso, avalia a situação das políticas que incidem na Amazônia brasileira, tendo como estudo de caso o mosaico formado pelo Parque Estadual e RPPN do Cristalino, localizados no Estado de Mato Grosso.The climate change is one of the major challenges of contemporary society, especially regarding its effects on the nature environment and biodiversity. The risks of climate change is not well known yet, and its consequences for biodiversity are being discovered at the moment. However, its impacts are beyond the changes in the natural environment and are also reflected at the policies and global relations. So, this paper analyzes the interrelationships between public policies on biodiversity and on climate change, considering the different scales of operation. It aims to identify how a world order problem unfolds at the local level. Thus, it verifies the situation of the public policies that impact on the brazilian Amazon, which the case study is the mosaic formed by the Parque Estadual e RPPN do Cristalino, located in Mato Grosso.
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Ciemer, Catrin [Verfasser], Jürgen [Gutachter] Kurths, Marina [Gutachter] Hirota, and Holger [Gutachter] Lange. "Complex systems analysis of changing rainfall regimes in South America and their implications for the Amazon rainforest / Catrin Ciemer ; Gutachter: Jürgen Kurths, Marina Hirota, Holger Lange." Berlin : Humboldt-Universität zu Berlin, 2019. http://d-nb.info/1189146568/34.
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Souza, Dennis Góss de. "Comparative analyses of microbial phylogenetic and functional processes following long-term land-use change." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-05012016-152905/.
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In the last years, microbial ecologists have dramatically increased their efforts to elucidate the \"black box\" of patterns and processes that modulate the diversity and functionality of soil microorganisms, examining their genetic diversity (e.g. through metagenomic) and measuring their functional characteristics. The aim of this thesis was to evaluate the interaction of the ecological processes of dispersion, diversification, selection and genetic drift on (1) the soil microbial communities, after conversion of forest to grassland or no-till cropping in long-term and (2) on the microbial communities in the rhizosphere of soybean in long-term no-till system. The cultivation of grassland in long-term led to a homogenizing selection of microbial communities, reducing beta-diversity, with consequent changes in the soil functions related to stress. No-till long-term led to minor changes of diversity, maintaining the functions found in the forest. The soybean plant has shown homogenizing power selection, and this increased with time. However, the functions selected in the rhizosphere were maintained, indicating functional resilience.Nos últimos anos, ecologistas microbianos aumentaram drasticamente seus esforços para elucidar a \"caixa preta\" dos padrões e processos que modulam a diversidade e funcionalidade dos microrganismos do solo, examinando sua diversidade genética (e.g. através de metagenômica) e medindo suas características funcionais. O objetivo dessa tese foi avaliar a interação dos processos ecológicos de dispersão, diversificação, seleção e deriva gênica, sobre (1) as comunidades microbianas do solo, após a conversão da floresta em pastagem ou plantio direto, em longo período e (2) sobre as comunidades microbianas da rizosfera de soja, em sistema de plantio direto, em longo período. O cultivo de pastagens em longo período levou a uma seleção homogeneizante das comunidades microbianas, reduzindo a beta-diversidade, com conseguinte alteração em funções no solo relacionadas ao estresse. O plantio direto em longo período levou a uma menor alteração da diversidade, com manutenção das funções encontradas na floresta. A planta de soja demonstrou poder de seleção homogeneizante, e este aumentou com o tempo. Contudo, as funções selecionadas na rizosfera foram mantidas, indicando resiliência funcional.
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Silva, Larissa Irene da. "Avaliação da atividade antimicrobiana, antioxidante e análise fitoquímica preliminar de plantas medicinais utilizadas pelas populações da região do Vale do Juruena e microrregião no Norte Araguaia, Mato Grosso, Brasil." Universidade Federal de Mato Grosso, 2015. http://ri.ufmt.br/handle/1/693.
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As doenças infecciosas estão entre as dez principais causas de óbitos no mundo. Os produtos naturais são fontes importantes de antibióticos. Sendo assim este trabalho se propõe a avaliar a atividade antibacteriana, antioxidante e bioprospectar alguns metabólitos secundários de plantas de uso popular na região do Vale do Juruena, e microrregião do Norte Araguaia, Mato Grosso, Brasil. Uma amostra de cada planta foi depositada no depositadas no Herbário da UFMT e no HERBAM. Os extratos das 99 espécies foram obtidos por maceração em solução hidroetanólica a 70%. A atividade antimicrobiana foi avaliada pelo método microdiluição em caldo, pelo qual se determinou a concentração inibitória mínima (CIM). Claritromicina e anfotericina (0,39 - 50 μg/mL), foram utilizadas como padrões, bacterianos e fúngicos, respectivamente. A capacidade antioxidante foi determinada pelos ensaios de DPPH, FRAP e NO usando-se ácido ascórbico como padrão, e, para este último quercetina. Dois extratos hidroetanólicos destacaram-se pelo amplo espectro de atividade antibacteriana: Bauhinia glabra (EHBg) e Terminalia argentea (EHTa). O EHBg apresentou boa atividade antibacteriana frente à Klebsiella pneumoniae (CIM = 25 μg/mL), moderada frente a Enterococcus faecalis (CIM = 200 μg/mL) e Streptococcus pyogenes (CIM = 400 μg/mL) e fraca atividade contra Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Shigella flexneri, Staphylococcus epidermidis e Bacillus subtilis (CIM = 800 μg/mL). O EHTa apresentou moderada atividade contra Staphylococcus aureus (CIM = 200 μg/mL), Enterococcus faecalis, Streptococcus pyogenes, Staphylococcus epidermidis e Bacillus subtilis (CIM = 400 μg/mL). Dois extratos hidroetanólicos destacaram-se pelo amplo espectro de atividade antifúngico: Bertholletia excelsa (EHBe), Cochlospermum regium (EHCch)e Qualea grandiflora (EHQg). O EHBe apresentou moderada atividade contra Aspergillus terreus (CIM = 100 μg/mL), Aspergillus fumigatus (CIM = 200 μg/mL), Candida glabrata e Cryptococcus neoformans (CIM = 400 μg/mL), e fraca atividade contra Candida albicans e Candida tropicalis (CIM = 800 μg/mL).O EHCch apresentou boa atividade contra Penicillium verrucosum, Trichophyton mentagrophytes e Microsporum gypseum (CIM = 6,25 μg/mL), moderada contra Candida albicans, Candida albicans fluconazol-resistente, Aspergillus fumigatus (CIM = 400 μg/mL) e fraca contra Aspergillus niger, Aspergillus parasiticus e Aspergillus terreus (CIM = 800 μg/mL). O EHQg demonstrou boa atividade frente a Trichophyton rubrum (CIM = 12,5 μg/mL) e fraca atividade contra Candida albicans, Candida albicans fluconazol-resistente, Candida tropicalis e Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus niger, Aspergillus parasiticus, e Aspergillus terreus (CIM = 800 μg/mL). Se destacaram pela sua atividade antioxidante, nos modelos de DPPH e FRAP, respectivamente, EHBe (CI50 = 0,39 ± 0,08 e 65,00 ± 8,67 μg/mL), Cariniana rubra (CI50 = 0,44 ± 016 E 64,00 ± 4,43 μg/mL) e Cedrela odorata (IC50 = 0,56 ± 0,08 and 56,37 ± 0,75μg/mL), nenhum extrato hidroetanólico testado exibiu CI no modelo de NO. Os teores de fenois totais nos extratos hidroetanólicos variaram de 0,06 a 10,91 mgEAt/g, os de flavonoides totais de 0,01 a 4,40 mgER/g e os de cumarinas, apresentarajm variação de 0,011 a 2,09 mgEC/g. Os resultados apontam a existência de componentes biológicamente ativos nas plantas medicinais da região do Vale do Juruena e microrregião no Norte Araguaia, ratificando seu o uso popular para o tratamento de infecções. Essas propriedades revelaram um grande potencial antimicrobiano e antioxidante dos extratos que poderiam ser aplicados futuramente na indústria farmacêutica, alimentar e cosmética.
Infectious diseases are among the ten leading causes of deaths worldwide. Natural products are important sources of antibiotics. Thus, this study aims to evaluate the antibacterial activity, antioxidant and bioprospect some secondary metabolites of popular use of plants in the region of the Juruena Valley and micro-region in North Araguaia, Mato Grosso, Brazil. A sample of each was deposited in deposited in the Herbarium of UFMT and HERBAM. The extracts of the 99 species were obtained by maceration in hydroethanol 70% solution. The antimicrobial activity was evaluated by the microdilution broth method by which it was determined the minimum inhibitory concentration (MIC), clarithromycin and amphotericin (0,39 - 50 μg/mL), were used as standards, bacterial and fungal, respectively. The antioxidant capacity was determined by DPPH, FRAP and NO using ascorbic acid as a standard, and for the latter quercetin. Two hydroethanolic statements highlighted by the broad spectrum of antibacterial activity: Bauhinia glabra (EHBg) and Terminalia argentea (EHTa). The EHBg showed good antibacterial activity against Klebsiella pneumoniae (MIC = 25 μg/mL), moderate against Enterococcus faecalis (MIC = 200 μg/mL) and Streptococcus pyogenes (MIC = 400 μg/mL) and weak activity against Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Shigella flexneri, Staphylococcus epidermidis e Bacillus subtilis (MIC = 800 μg/mL). The EHTa showed moderate activity against Staphylococcus aureus (MIC = 200 μg/mL), Enterococcus faecalis, Streptococcus pyogenes, Staphylococcus epidermidis e Bacillus subtilis (MIC = 400 μg/mL). Two hydroethanolic extracts highlighted by the broad spectrum of antifungal activity: Bertholletia excelsa (EHBe), Cochlospermum regium (EHCch) andd Qualea grandiflora (EHQg). The EHBe showed moderate activity against Aspergillus terreus (MIC = 100 μg/mL), Aspergillus fumigatus (MIC = 200 μg/mL), Candida glabrata and Cryptococcus neoformans (MIC = 400 μg/mL), and weak activity against Candida albicans and Candida tropicalis (MIC = 800 μg/mL). The EHCch showed good activity against Penicillium verrucosum, Trichophyton mentagrophytes and Microsporum gypseum (MIC = 6,25 μg/mL), moderate against Candida albicans, Candida albicans fluconazole-resistent, Aspergillus fumigatus (MIC = 400 μg/mL) and weak against Aspergillus niger, Aspergillus parasiticus and Aspergillus terreus (MIC = 800 μg/mL). The EHQg showed good activity against Trichophyton rubrum (MIC = 12,5 μg/mL) and weak against Candida albicans, Candida albicans fluconazole-resistent, Candida tropicalis and Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus niger, Aspergillus parasiticus, and Aspergillus terreus (MIC = 800 μg/mL). Stood out for their antioxidant activity in models of DPPH and FRAP, respectively, EHBe (IC50 = 0,39 ± 0,08 e 65,00 ± 8,67 μg/mL), Cariniana rubra (IC50 = 0,44 ± 016 E 64,00 ± 4,43 μg/mL) and Cedrela odorata (IC50 = 0,56 ± 0,08 and 56,37 ± 0,75μg/mL), no hydroethanolic extract tested exhibited IC in the model. The total phenols content in hydroethanolic extracts ranged from 0,06 - 10,91 mgEAt/g, the total flavonoids 0,01 a 4,40 mgER/g and the coumarins showed variation from 0,011 - 2,09 mgEC/g. The results show the existence of biologically active components in medicinal plants Juruena Valley region and micro region in North Araguaia, confirming its popular use for the treatment of infections. These properties showed strong antimicrobial and antioxidant potential of extracts that could be applied in the future in the pharmaceutical, food and cosmetics.
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Silva, Carine Klauberg. "Potencial produtivo e de manejo de dois produtos florestais não madeireiros no contexto Amazônico - o cipó-titica (Heteropsis spp.) e o óleo de copaíba (Copaifera spp.)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-12082014-111232/.
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O óleo resina de copaíba (Copaifera spp.) e as fibras das raízes de cipó-titica (Heteropsis spp.) são produtos florestais não madeireiros, de grande importância social e econômica, principalmente para comunidades presentes na região Amazônica. Entretanto, faltam estudos que ajudem a definir e melhorar leis e práticas de manejo. O objetivo deste estudo foi preencher essa lacuna, avaliando os fatores bióticos e abióticos que afetam o desenvolvimento e a produtividade destas espécies. O primeiro capítulo trata de espécies de Copaifera, e a produção de óleo resina por árvore e os ciclos de manejo. Com 118 copaibeiras amostradas, sob até três extrações dentro de ciclos de um a cinco anos, foram testados modelos de regressão logística e linear múltiplo para avaliar os fatores correlacionados com a produção. Ainda, foi avaliada a produtividade física (óleo resina), e monetária (valor presente líquido), ao final de cada ciclo, sob os cenários determinístico e estocástico. Como resultado, o diâmetro, a presença de pragas, a qualidade do fuste/copa, as espécies e os ciclos, foram relevantes com relação à probabilidade de produção de óleo resina. A produção também esteve relacionada com o ciclo, a extração e com as espécies, sendo que o ciclo de três anos foi mais viável, tanto na perspectiva monetária quanto de produção, e em ambos os cenários. No segundo capítulo discutimos sobre Heteropsis spp. Foi avaliada a produtividade em relação à quantidade e qualidade de suas raízes, após dois anos da colheita, com intensidades de corte de 50% e 100%. Ademais, em outras áreas florestais, foi inventariada outra população de cipó-titica, e testados métodos de amostragem que providenciassem uma maior eficiência, menor erro amostral e melhor estimativa de produção por área. Foi aplicada a regressão de Poisson, para comparar as unidades amostrais entre os períodos (2009-2011) e tratamentos de corte, e a análise de variância para avaliar o efeito dos tratamentos sobre características do solo. Foram realizadas simulações para testar diferentes métodos de amostragem (aleatório e sistemático) com diferentes tamanhos e formatos de parcelas. Em síntese, o ciclo de manejo de até dois anos e extrações das raízes comerciais acima de 50% demonstraram não serem viáveis para garantir a produtividade e a qualidade das raízes de cipó-titica. Logo, amostragem sistemática ou aleatória, com intensidades variando de 15-20%, e parcelas de 250-300 m² produzem boas estimativas de produção, com erros abaixo de 15%.The oleoresin of copaiba (Copaifera spp.) and the fibers of the roots of cipó-titica (Heteropsis spp.) are non-timber forest products of great social and economic importance, especially for communities in the Amazon region. However, there are few studies that help to define and improve laws and management practices. The aim of this study was to fill this gap by assessing the biotic and abiotic factors that affect the development and productivity of these species. The first chapter deals with the species of Copaifera, and oleoresin production per tree, cycles and population structure. With 118 copaibeiras sampled in up to three extractions in cycles of one to five years, logistic regression and multiple linear models were tested to evaluate factors related to the production. Still, the physical productivity (oleoresin) was evaluated, and monetary (net present value) at the end of each cycle, under the deterministic and stochastic scenarios. As a result, the diameter, the presence of pests, the quality of the canopy/trunk, and species cycles were relevant in connection with the probability of bigger production oleoresin. The production was related to the cycle, extraction and species, and the three-year cycle was more feasible, both in the monetary or production perspectives, and in both scenarios. In the second chapter we discuss Heteropsis spp. productivity in terms of quantity and quality of roots. It was evaluated after two years of harvest, with cutting intensities of 50% and 100%. Moreover, in other forest areas, we inventoried another population of Heteropsis, and tested sampling methods that arrange to higher efficiency, smaller sampling error and better estimation of production per area. Poisson regression was used to compare the sample units between periods (2009-2011) and cutting treatments, and analysis of variance to assess the effect of treatments on soil characteristics. Simulations were performed to test different sampling methods (random and systematic) with different sizes and shapes of plots. In summary, the cycle of handling up to two years and extractions of commercial roots above 50% proved to be not feasible to ensure productivity and quality of the roots of Heteropsis. Therefore, systematic or random sampling, with intensities ranging from 15-20%, and plots of 250-300 m² produce good estimates of production, with errors below 15%.
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Mosnier, Emilie. "Epidémiologie des maladies infectieuses et épidémiques en milieu isolé Amazonien." Thesis, Guyane, 2017. http://www.theses.fr/2017YANE0007/document.
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Les études dans les régions isolées de la Guyane française sont rares. L'objectif principal de ce travail est d'analyser les principales données épidémiologiques résultant de des investigations sur les maladies infectieuses et épidémiques menées dans les centres de santé des régions isolées et frontalières de la Guyane. L’étude portant sur les personnes vivant avec le VIH a mit en évidence sur le plan spatial l'importance des zones fluviales frontalières qui constituent des zones actives de l’épidémie en termes de passage et de possible propagation mais aussi en termes de prévention, dépistage et traitement. Les investigations des épidémies de shigellose, de grippe et surtout de béribéri chez les orpailleurs soulignent le lien entre conditions de vie dégradées et problématiques de santé. La description des cas groupés de cryptosporidiose chez les enfants immunocompétents amérindiens reflètent les composantes multifactorielles des épidémies en zones isolées mettant en jeux des comportements humains spécifiques au sein d’écosystèmes tropicaux. La sévérité et la diversité des co-infections associés au besoin primaire de sécurité nutritionnelle rappellent les difficultés mais aussi l’urgence de l’adaptation des politiques de santé publiques aux populations éloignées. Enfin, l’étude menée sur le paludisme autochtone a tenté de discuter d’une nouvelle approche afin d’identifier et de traiter les infections asymptomatiques dans une zone de transmission endémique. La description des enjeux sanitaires et de l'état de santé des populations isolées dans les régions éloignées est cruciale pour la mise en œuvre d'une politique de santé optimisé en GuyanePublic health data in isolated areas of French Guiana are scarce. However, a number of different communities live in tropical forest areas.The principal objective of this study is to analyse the main epidemiological data that have resulted from clinical practice and investigations conducted at health centres in isolated areas of French Guiana and its borders. The results of HIV studies have highlighted particular events that promote the spread of outbreaks. Illegal gold miners therefore represent a significant number of cases. The importance of specific geographical border areas in epidemic dynamics has also been demonstrated. Investigations on shigellosis, influenza and, most importantly, on thiamine deficiency outbreaks in gold miners underline that precarious conditions lead to poor health. Cryptosporidiosis outbreaks among immunocompetent children also reflect the multifactorial dynamics of infectious diseases, including human behaviour and the characteristics of tropical ecosystems. The severity and diversity of parasitic, viral and bacterial co-infection associated to the need for nutrition security indicates the complexity of delivering medical care to remote populations. Finally, a study on malaria has attempted to offer a novel approach to identifying and treating asymptomatic infections in an Amerindian endemic transmission area. A description of the health status of neglected populations in remote areas is crucial to implementing a health policy in French Guiana. Considering the importance of controlling communicable disease and the severity and range of specific illnesses, new strategies are needed and should be discussed with the communities involved
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Sampaio, Shaula Maíra Vicentini de. "“Uma floresta tocada apenas por homens puros...” ou do que aprendemos com os discursos contemporâneos sobre a amazônia." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/49082.
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A presente tese reflete sobre uma rede discursiva a partir da qual são produzidas (e ensinadas) algumas verdades sobre a floresta amazônica, entre as quais está o entendimento de que as populações designadas tradicionais apresentam modos de habitar esse espaço e de se relacionar com a natureza dessa região considerados mais adequados e sustentáveis. Dessa forma, o argumento central que o estudo desenvolve é que a noção de sustentabilidade atua como um dispositivo estratégico na constituição e regulação das relações processadas entre as populações tradicionais e a floresta amazônica. Com base nisso, foram focalizados discursos contemporâneos sobre a Amazônia e as populações que lá vivem, por meio da análise de textos publicados em jornais brasileiros de ampla circulação entre os anos de 2007 e 2011. A perspectiva teórica que norteou o estudo se inscreve no campo dos Estudos Culturais, valendo-se, ainda, de teorizações do filósofo Michel Foucault (como as noções de dispositivo e de discurso). Com o intuito de abordar as condições que possibilitaram a emergência dos discursos contemporâneos sobre a floresta amazônica e seus habitantes “tradicionais”, são debatidas algumas questões que, historicamente, contribuíram para a invenção de diferentes modos de pensar e agir com relação à Amazônia – desde as narrativas produzidas no período colonial aos recentes discursos ambientalistas sobre a devastação da floresta. A noção de população tradicional também é problematizada, uma vez que há uma série de controvérsias envolvendo tal conceito, especialmente as que dizem respeito à vinculação de tal noção com a ideia de “bom selvagem ecológico”. Cabe indicar que, na realização das análises, foram definidos eixos temáticos que se centraram nos seguintes aspectos: 1) as tensões e impasses entre discursos “desenvolvimentistas” e “preservacionistas”, acompanhados da proposição do desenvolvimento sustentável como uma alternativa para solucionar os conflitos na Amazônia; 2) os enunciados que apontam a importância das populações tradicionais para a conservação da biodiversidade, em função de seu estilo de vida mais “puro” e “integrado com a natureza”; 3) a intensificação da inserção da floresta amazônica e das populações tradicionais nas redes do capitalismo transnacional, principalmente através da disseminação dos discursos sobre as mudanças climáticas globais. Em síntese, com base nas discussões realizadas, é possível dizer que aprendemos muitas lições sobre a floresta amazônica e as populações tradicionais ao folhearmos as páginas dos jornais, mas talvez a mais importante delas se refira ao papel incisivo que o mercado vem assumindo no jogo de forças relativo ao que deve ser feito com a floresta e com seus habitantes. Desse modo, as linhas do dispositivo da sustentabilidade se intensificam, produzindo novas formas de regulação da floresta e dos povos nela vivem. Ademais, é importante considerar que essas lições que aprendemos com os discursos contemporâneos sobre a Amazônia dizem respeito também a questões que nos implicam e nos convocam a assumir posicionamentos com relação aos discursos ambientalistas, aos discursos econômicos, aos discursos sobre sustentabilidade, entre tantos outros.This thesis deals with a discursive network from which some truths about the Amazon rainforest are produced (and taught). Among them is the understanding that the socalled traditional populations present modes of inhabiting this space and relating to nature from this region which are considered more appropriate and sustainable than others. In this way, the chief argument developed in this study aims to point out that the notion of sustainability acts as a strategic tool in the regulation and establishment of relations processed between traditional populations and the Amazon rainforest. Based on this, contemporary discourses on the Amazon and the people who live there were the focus of the analysis of texts published in Brazilian newspapers of wide circulation between the years 2007 and 2011. The theoretical perspective which guided this study falls within the field of Cultural Studies, making use, also, of theories of the philosopher Michel Foucault (such as the notions of device and discourse). In order to address the conditions that have allowed the emergence of contemporary discourses on the Amazon rainforest and its "traditional" inhabitants, some issues which have historically contributed to the invention of different ways of thinking and acting in relation to the Amazon are discussed here; contemplating from the narratives produced in the colonial period to recent environmental discourses about the devastation of the forest. The notion of traditional population is also problematized, since there has been a lot of controversy surrounding this concept, especially those relating to the linkage of such a notion with the idea of a "ecologically noble savage". It is worth mentioning that, in the analysis, were defined themes that focused on the following aspects: 1) the tensions and deadlocks between the "developmental" and "preservationists" discourses followed by the proposition of the idea of sustainable development as an alternative to solve the conflicts in the Amazon; 2) the statements which highlight the importance of traditional populations for conservation of biodiversity, since it is attributed to them a life style considered more "pure" and "integrated with nature"; 3) the intensive insertion of the Amazon forest and traditional populations in the networks of transnational capitalism, especially through the dissemination of the discourses about global climate change. In summary, based on the discussions that follow this study, one can say that – as we flip through the pages of newspapers – we have learned many lessons about the Amazon rainforest and its traditional populations, but, perhaps, the most important one concerns the incisive role that the market has been taking in the game forces relative to what should be done with the forest and its inhabitants. Thus, the lines of the sustainability device grow intense, producing new forms of regulation of the forest and the people who live there. Moreover, it is important to consider that these lessons we have learned from the contemporary discourses on the Amazon also relate to issues which involve and call us to take a stand with respect to environmental discourses, economic discourses, the discourses on sustainability, among many others.
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Douine, Maylis. "Epidémiologie du paludisme chez les personnes travaillant sur des sites d’orpaillage illégal en Guyane : Quels enjeux pour la santé publique ?" Thesis, Guyane, 2017. http://www.theses.fr/2017YANE0006/document.
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Introduction : Bien que les données officielles fassent état d’une diminution globale du nombre de cas de paludisme en Guyane, les orpailleurs travaillant sur les sites illégaux au cœur de la forêt amazonienne semblent très touchés par cette pathologie. L’objectif principal de cette étude était de déterminer la prévalence du paludisme dans cette population. Les objectifs secondaires évaluaient la proportion des différentes espèces plasmodiales et leur distribution géographique, le niveau de résistance des parasites aux dérivés de l’artémisinine, les connaissances attitudes et pratiques vis à vis de cette pathologie, et des données de santé de cette population. Matériel et méthodes : Les inclusions ont eu lieu sur les sites de repli des orpailleurs le long du fleuve Maroni. Après recueil du consentement éclairé, un test de diagnostic rapide du paludisme était effectué, ainsi qu’un questionnaire, un examen clinique, et un prélèvement de sang pour microscopie, PCR et tests de résistance (RSA et génotypage du gène pfK13 pour les PCR positives à Plasmodium falciparum). Résultats : De janvier à juin 2015, 421 orpailleurs ont été inclus, majoritairement des hommes (70,6%) brésiliens (93,8%), de médiane d’âge de 37 ans. La prévalence du portage de plasmodies déterminée par PCR était de 22,3% (IC95% : 18,3-26,3) à 84% asymptomatiques. Les espèces identifiées étaient principalement P. falciparum (47,9%) puis P. vivax (37,2%) avec 10,6% de coinfections. Lors du dernier accès palustre, 52,4% des orpailleurs avaient eu recours à l’automédication, majoritairement avec des dérivés de l’artémisinine (93,8%) avec une mauvaise observance (37,8%). Le fait d’être en Guyane était fortement associé à l’automédication (AOR=22,1). Le test RSA montrait un taux de survie supérieur à 1% pour un échantillon mais l’analyse du gène pfK13 ne mettait pas en évidence de mutations associées à la résistance à P. falciparum Discussion: La prévalence élevée de porteurs asymptomatiques de paludisme constitue un réservoir important pourla transmission du paludisme dans la région. L’utilisation massive de dérivés de l’artémisinine associée à une mauvaise observance sont des facteurs de risque d’émergence de résistance, ce qui entraînerait des conséquences sanitaires et économiques importantes. Avec une volonté politique, des actions sont possibles pour limiter ce risque, comme la distribution de kits d’autodiagnostic et d’auto-traitement avec une formation au niveau des sites de repliIntroduction: Although official data show a global decrease of malaria in French Guiana, this disease often affects illegal gold miners working in the deep Amazonian forest. The main objective of this study was to evaluate the malaria prevalence in this population. The secondary objectives were to evaluate and map the proportion of Plasmodium species, to assess behavior, attitudes and practices regarding malaria in this population, to measure the artemisinin resistance level in parasites and to evaluate their general health. Material and methods: Inclusions took place at the gold miners’ resting sites, spread along the Maroni river. After recording their informed consent, a malaria rapid test was performed, as well as a questionnaire, a clinical exam and a blood sample for microscopy, PCR and resistance test (RSA and PfK13 genotyping for P. falciparum positive samples). Results: From January to June 2015, 421 gold miners were included, mainly men (sex ratio 2.4), Brazilian nationals (93.8%), with a median age of 37 years. Plasmodium prevalence using PCR was 22.3% (CI95%: 18.3 - 26.3), of whom 84% were asymptomatic. During the last malaria attack, 52.4% selfmedicated with artemisinin derivatives (93.8%) and a poor treatment adherence (37.8%). Being in French Guiana when the malaria attack occurred was strongly associated with selfmedication (AOR=22.1). One sample showed a survival rate higher than 1% in RSA test but PfK13 genotyping did not reveal any mutation in P. falciparum. Discussion: This high prevalence of asymptomatic carriers constitutes a huge reservoir for malaria transmission in the region. Massive use of artemisinin derivatives associated with poor treatment adherence are factors that may contribute to the emergence of artemisinin resistance. That would have huge sanitary and economical consequences. With political will, actions are possible to limit this risk, as the distribution of kits for self diagnosis and self-treatment with training on resting sites
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Adenis, Antoine. "L’histoplasmose chez le patient infecté par le VIH en Guyane française." Thesis, Guyane, 2017. http://www.theses.fr/2017YANE0014/document.
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L’histoplasmose est une infection fongique invasive. Elle était décrite comme une des principales infections opportunistes et une des premières causes de décès au stade SIDA en Guyane française.Plusieurs travaux scientifiques ont été menés. Classée première infection opportuniste au stade SIDA, l’incidence de l’histoplasmose était estimé à 1,5 p100 personne-années infectées par le VIH. Le nombre de cas incidents était stable à un niveau élevé et la proportion de décès précoces <10%. Avec une surincidence des cas en fin de saison sèche et début de petite saison des pluies, le principal processus menant à une maladie symptomatique était une nouvelle infection. La comparaison des cas de tuberculose et d’histoplasmose retrouvait respectivement, un profil clinique respiratoire dans un contexte inflammatoire marqué et, un profil disséminé accompagné de cytopénies et d’anomalies hépatiques chez des patients plus immunodéprimés. L’évaluation de la détection sérique de l’antigène galactomananne était pertinente pour le diagnostic de l’histoplasmose. Une redéfinition des critères de sévérité et le développement d’arguments pour une stratégie thérapeutique empirique à visée antifongique étaient proposés.Des résultats préliminaires démontraient la présence (au Suriname et au Guyana) et une incidence importante de l’histoplasmose chez les patients infectés par le VIH du Suriname. A l’échelle de l’Amérique Latine, la mortalité liée à l’histoplasmose était estimée équivalente voire supérieure à celle de la tuberculose chez les patients infectés par le VIH. L’histoplasmose y était jugée négligée, méconnue, responsable de nombreux décès évitablesHistoplasmosis is an invasive fungal infection, known as one of the first AIDS-defining condition and AIDS-related deaths in French Guiana.Several scientific programmes were conducted. Ranked as the main AIDS-defining condition, histoplasmosis incidence was estimated at 1.5 p100 person-years HIV-infected. The high number of incident cases was stable and the proportion of early deaths was <10%. Following a significant increase in incidence between the end of the long dry season and the beginning of the short wet season, new infection might be the main pathophysiological mechanism leading to symptomatic disease in endemic areas. Comparison of tuberculosis and histoplasmosis in HIV-infected patients found a respiratory clinical picture in a context of pronounced inflammation and, a disseminated disease along with cytopenia and liver test abnormalities in individuals with greater immunosuppression, respectively. An evaluation of galactomannan antigen detection in serum was relevant for histoplasmosis diagnosis. Reframed severity criteria and arguments for an empiric strategy using antifungal therapy were proposed.Preliminary results showed the presence (in Suriname and Guyana) and a high incidence of histoplasmosis among HIV-infected patients in Suriname. In the whole Latin American region, we estimated that AIDS-related histoplasmosis deaths were similar or greater than AIDS-related tuberculosis deaths. HIV-associated histoplasmosis is in fact neglected, largely unknown and responsible for numerous avoidable deaths in Latin America
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Campos, Érica Ferraz de. "Emissão de CO2 da madeira serrada da Amazônia: o caso da exploração convencional." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3146/tde-12062013-170523/.
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Informações ambientais de materiais e produtos são essenciais para a gestão de sustentabilidade no setor de construção. Em função das mudanças climáticas, o fator de emissão de dióxido de carbono (CO2) de produtos torna-se relevante para inventariar projetos e edificações, e pautar a decisão de profissionais e consumidores. Com base na metodologia de Análise de Fluxo do Material, a presente pesquisa objetivou quantificar o fator de emissão de CO2 da madeira serrada da Amazônia originária de exploração convencional. O recorte abrangeu a extração de toras da floresta, transporte de toras até serraria, processamento primário e transporte de madeira serrada ao mercado consumidor. Foram consideradas para o cálculo as emissões advindas de resíduos de biomassa e consumo de energia fóssil. Os resultados são apresentados em faixas de valores mínimos a máximos, para cada etapa produtiva, com o objetivo de incorporar incertezas e variações relativas às características do ambiente florestal e procedimentos da atividade madeireira. A quantificação foi principalmente baseada em dados de literatura; entrevistas e questionários com madeireiras da região foram utilizados para determinar o consumo de energia no processo. Entre 200 t/ha e 425 t/ha de biomassa seca acima do solo compõem a floresta Amazônica, de acordo com as características regionais. Essa biomassa estoca de 98 tC/ha a 208 tC/ha. Na exploração convencional são extraídas de 3 a 9 árvores por hectare, estimadas entre 4% e 14% da biomassa. Durante a extração, de 7% a 33% da biomassa florestal é danificada para abertura de trilhas, derrubada de árvores comerciais e arraste de toras. A biomassa destruída na extração é geralmente abandonada na floresta, onde se decompõe, gerando emissões. Nas serrarias, devido ao baixo aproveitamento, pelo menos 54% da biomassa das toras é transformada em resíduos, que são queimados ou degradam, outra fonte de CO2. Somando floresta e serraria, são produzidos de 5,0 t/t a 8,5 t/t na relação entre resíduos e madeira serrada. As emissões relativas aos resíduos, por unidade de tora processada, são estimados de 3,4 tCO2/t a 9,7 tCO2/t. As emissões por consumo de energia para extração, transporte de toras e processamento contribuem com 0,02 tCO2/t a 0,12 tCO2/t de tora processada. Ao final do processo produtivo, estimou-se a faixa de variação das emissões de 7,5 tCO2/t a 28,4 tCO2/t de madeira serrada, equivalentes a 5,2 tCO2/m³ e 19,6 tCO2/m³. Outra etapa considerada foi o transporte do produto entre serraria e mercado consumidor, que incrementa em 0,03 tCO2/t a 0,12 tCO2/t de madeira serrada, se admitidos 1.956 km, estimativa de distância média percorrida legalmente com a madeira amazônica no Brasil. O fator de emissão de CO2 da madeira serrada da Amazônia pode fundamentar políticas públicas para sua mitigação na atividade madeireira, bem como pautar iniciativas do setor público, construção civil e consumidores. A destruição da floresta foi identificada como a principal influência no fator de emissão de CO2 da madeira serrada. Para mitigação do CO2 nessa etapa, o modelo convencional de exploração precisaria ser revisto, o que conjuntamente promoveria a conservação da floresta. O aproveitamento de resíduos de floresta e serraria configura outra oportunidade relevante para a redução de impacto ambiental do produto. A parcela de contribuição da produção de madeira serrada Amazônica sobre as emissões brasileiras de 2005 foi estimada entre 3,5% e 13,1%. Para a proposição de ações eficazes, o impacto de diversos modelos de exploração madeireira precisa ser medido e sua análise ser aprofundada, para as diferentes regiões da floresta Amazônica.Environmental information of materials and products are essential for sustainability management in construction. Due to climate change, CO2 emission of products are relevant to inventory buildings and projects and to guide professionals\' and consumers decisions. Based on Material Flow Analysis, this research aim to quantify CO2 emission factor of Amazon lumber from conventional logging. The study included stages of logging, transportation of logs, sawing and lumber transportation. CO2 emissions from residues of biomass and energy consumption were considered in quantification. The results are presented in ranges for each stage of chain production, in order to incorporate uncertainties and variations of forest characteristics and procedures. Quantification was mainly based on literature; interviews with logging companies were used to define energy consumption. Amazon rainforest is composed of 200 t/ha to 425 t/ha of above ground dry biomass, which depends on forest region, and stocks between 98 tC/ha and 208 tC/ha. In conventional logging 3-9 trees per hectare are usually extracted, estimated as 4% to 14% of forest biomass. During logging, from 7% to 33% of the forest biomass is damaged to open trails, fall trees and remove commercial logs. The damaged biomass is usually left at forest, where it decomposes, causing CO2 emissions. In sawmills, at least 54% of the biomass is transformed into residues, which are burned or degraded, other CO2 source. Combining forest and sawmill residues, from 5.0 t residues/ t lumber to 8.5 t/t are generated. The CO2 emissions from residues of biomass, per unit of processed roundwood, are estimated from 3.4 tCO2/t to 9.7 tCO2/t. Energy consumed in extraction, logs transportation and sawing contribute with 0.02 tCO2/t to 0.12 tCO2/t of processed roundwood. At the end of the production, emissions were estimated from 7.5 tCO2/t to 28.4 tCO2/t of lumber, equivalent to 5.2 tCO2/m³ to 19.6 tCO2/m³. Lumber transportation from sawmills to consumer market is another stage that increases emissions from 0.03 tCO2/t to 0.12 tCO2/t of lumber, if admitted 1,956 km, the estimated average distance for legal Amazon lumber transportation in Brazil. CO2 emission factor of Amazon lumber may contribute to mitigation policies in wood sector, as well as guide initiatives of public sector, construction sector and consumers. The destruction of forest biomass was identified as the main influence on CO2 emission factor of Amazon lumber. To minimize CO2 emissions the conventional model of exploitation need to be revised, what would also promote Amazon rainforest conservation. The use of residues from forest and sawmills is another relevant opportunity to reduce environmental impact of lumber. The contribution of Amazon lumber in Brazilian CO2 emissions, based on 2005 data, was estimated from 3.5% to 13.1%. To propose effective actions, the impact of logging in different models of exploitation must be measured in different regions of Amazon forest.
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Trevizor, Tássio Ticiano. "Anatomia comparada do lenho de 64 espécies arbóreas de ocorrência natural na floresta tropical amazônica no estado do Pará." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-02082011-132019/.
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Os estudos da anatomia macro e microscópica do lenho como ferramenta auxiliar na taxonômia, sobretudo na identificação de espécies florestais, vêm sendo utilizados há décadas. A análise comparativa da estrutura anatômica do lenho permite a identificação de características morfológicas exclusivas das ordens, famílias, gêneros e, em muitos casos, de espécies, aumentando a gama de caracteres utilizados na descrição e identificação botânica de espécies arbóreas pela taxonomia clássica. No presente trabalho, foram utilizadas técnicas de análise comparativa e de descrição da estrutura anatômica macro e microscópica do lenho de árvores de espécies que ocorrem naturalmente na floresta tropical Amazônica nos municípios de Santarém, Mojú, Paragominas e Tailândia, no estado do Pará. Os objetivos do trabalho foram (i) caracterizar a estrutura anatômica macro e microscópica do lenho; (ii) identificar as características de valor taxonômico através de análise comparativa da estrutura anatômica do lenho; (iii) elaborar chaves de identificação das espécies pela estrutura anatômica macro e microscópica do lenho. Foram analisadas 100 amostras do lenho do tronco de árvores de 64 espécies, coletadas em 2004, pelo projeto Dendrogene/Embrapa Amazônia Oriental. A superfície das amostras do lenho foi polida com lixas e navalhas, seguindo-se a sua descrição macroscópica; lâminas histológicas do lenho foram preparadas com navalha de micrótomo de deslize, para a descrição microscópica do lenho. Os resultados possibilitaram, pela análise comparativa da estrutura anatômica do lenho, confeccionar as chaves de identificação macroscópica de 49 espécies dos 51 gêneros. Os gêneros Hymenolobium e Virola com 4 e 2 espécies, respectivamente, não puderam ser separados. A chave de identificação microscópica permitiu identificar 64 das espécies estudadas. A análise comparativa do lenho permitiu, da mesma forma, evidenciar 25 espécies com potencial para a dendrocronologia, sendo 10 e 15, com anéis de crescimento com distintos e pouco distintos, respectivamente. A aplicação da anatomia do lenho como importante ferramenta com potencial a taxonomia de espécies florestais é discutida no presente trabalhoStudies of macro and microscopic wood anatomy as an auxiliary tool in taxonomy, particularly in the identification of forest tree species, have been used for decades. Comparative analysis of the wood anatomical structure allows the identification of unique morphological characteristics of the orders, families, genera, and in many cases, species, increasing the range of characters used in the botanical description and identification of tree species by classical taxonomy. In this work, techniques were used for comparative analysis and description of the anatomical structure of macro and microscopic wood tree species, that occur naturally in the Amazon rainforest in the Santarém, Mojú Paragominas and Tailândia cities, in Pará State. The aims of the study were (i) to characterize the macro and microscopic anatomical wood structure, (ii) identify the characteristics of taxonomic value through a comparative analysis of the wood anatomical structure, (iii) prepare the keys for species identification by macroscopic and microscopic wood anatomical structure. Were analyzed 100 wood samples from 64 tree species collected in 2004, in the project Dendrogene/Embrapa Amazonia Oriental. The surface of wood samples was polished with sandpaper and knives, according to their macro description; histological wood sections were prepared with razor sliding microtome, for microscopic wood description. The results allowed for the comparative analysis of the anatomical wood structure, to produce the macroscopic identification keys to 49 species of 51 genera. The genera Hymenolobium and Virola species with 4 and 2, respectively, could not be separated. The results from comparative wood anatomy showed evidence of 25 tree species with high potential for dendrochronological studies in order to distinct tree-ring presence (10 species) and barely distinct tree-rings (15 species). The application of wood anatomy, as an important tool with the potential of forest species taxonomy is discussed in this paper.
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Epelboin, Loïc. "Émergence de zoonoses en Amazonie : épidémiologie comparée de la leptospirose et de la fièvre Q en Guyane française." Thesis, Guyane, 2017. http://www.theses.fr/2017YANE0013/document.
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Parmi les nombreuses pathologies infectieuses dignes d’intérêt en Guyane, deux d’entre elles, deux zoonoses, ont connu récemment un regain d’intérêt conduisant en quelques années à améliorer nettement leur connaissance, mais également découvrir des particularités épidémiologiques inattendues qui nous ont amené à nous poser la question de leur caractère émergent ou réémergent. Bien que cosmopolite et à tropisme tropical, la leptospirose n’a que peu été décrite en Guyane et sur le bouclier des Guyanes. La littérature repose sur des cas cliniques ou série de cas anciens, la dernière publication remontant à 1995. Sont présentées ici plusieurs études qui ont permis d’en savoir un peu plus sur cette infection bactérienne : revue exhaustive de la littérature, étude rétrospective des rapports du CNR, étude rétrospective multicentrique sur les leptospiroses prises en charge en Guyane entre 2007 et 2014, avec analyse de ses déterminants, démographiques, écologiques, cliniques, séro-épidémiologique, comparaison de ses formes graves à celles d’Afrique du Nord. Bien que sa présence ait été identifiée dès les années 50 en Guyane, la fièvre Q ou infection à Coxiella burnetii, n’avait suscité localement aucun intérêt jusqu’à la fin des années 1990. Le travail ici présente la progression des connaissances sur cette infection bactérienne, également cosmopolite, mais avec des spécificités locales tout à fait inédites. Au fil des découvertes sur cette bactérie à la sauce guyanaise, nous présenterons la contribution de notre équipe à la progression du savoir sur cette pathologie et l’apport de réponses amenant tout autant de nouvelles. Ainsi les réflexions portent autour de ce génotype si particulier, le MST17, trouvé exclusivement en Guyane, qui entraine l’incidence la plus élevée au monde de la fièvre Q, une prévalence élevée parmi les pneumopathies retrouvée nulle ailleurs. En outre, le cycle épidémiologique de la bactérie, habituellement fondé sur le bétail, semble ici suivre un tout autre chemin et trouver son réservoir dans la faune sauvage. L’on s’interroge également sur le contraste entre le problème de santé publique majeur que cette maladie représente en Guyane et le caractère tout juste anecdotique dans le reste de l’Amérique latine.Finalement, bien que ces deux zoonoses puissent être qualifiées de « maladies nouvelles » en Guyane, il s’agit probablement pour la leptospirose d’une augmentation récente du nombre de cas lié à l’amélioration des techniques diagnostiques et à la sensibilisation des médecins à cette maladie, tandis que la fièvre Q semble présenter un véritable profil émergent, avec augmentation récente de son incidence, et de nombreuses inconnues lié à un génotype très particulier.Plusieurs questions concernant ces deux infections restent encore sans réponse, et le travail est immense pour mieux comprendre les enjeux de ces deux maladies, tant à l’échelle de la Guyane qu’à celle du continent latino-américainAmong the numerous infectious diseases of interest in French Guiana (FG), two of them, two zoonoses, have recently experienced a revival of interest leading in a few years to a marked improvement in their knowledge. Several studies allowed as well discovering unexpected epidemiological features that have led us to question their emerging or reemerging character.Although cosmopolitan and with tropical a tropism, leptospirosis has been barely described in FG and on the Guiana Shield. The literature is old and reports only clinical cases or series, the most recent publication dating back to 1995. Several studies are presented in this work which have allowed to know a little more about this bacterial infection: exhaustive review of the literature, retrospective study of the reference national center reports, a retrospective multicenter study on leptos-piroses managed in FG between 2007 and 2014, with analysis of its determinants, demographic, ecological, clinical, sero-epidemiological, and a study comparing Guianese severe forms to those of North Africa.Although its presence had been suspected as early as the 1950s in FG, Q fever or Coxiella burnetii infection had not aroused interest locally until the late 1990s. The work here presents the progression of the knowledge of this bacterial infection, also cosmopolitan, but with unusual local specificities. In the course of the discoveries around this Guianese outbreak, we will present the contribution of our team to the progression of knowledge on this pathology and the contribution of answers bringing as much new questions. Thus the discussion will focus on this particular genotype, MST17, found exclusively in FG, which results in the highest incidence of Q fever in the world, a prevalence among pneumonias never found elsewhere. Moreover, the epidemiological cycle of the bacterium, usually based on livestock, seems to follow a completely different path and find its reservoir in wildlife. We also wonder about the contrast between the major public health problems that this disease represents in FG and the anecdotal character in the rest of Latin America.Finally, although these two zoonotic diseases may be described as "new diseases" in FG, it is likely that leptospirosis presents a recent increase in the number of cases related to the improvement of diagnostic techniques and the sensitization of physicians to this disease, but without real emergence, while Q fever seems to present a true emergent profile, with a recent increase in its incidence, and many unknowns linked to a very particular genotype.Many questions concerning these two infections remain unanswered, and the work is immense to better understand the stakes of these two diseases, both on the scale of FG and that of the Amazonian region and the Latin American continent
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Medeiros, João Carlos. "Funções de pedotransferência em estudos do funcionamento hídrico do solo da região sudeste do estado do Pará." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-26032012-105416/.
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O entendimento dos processos hídricos do solo, tais como infiltração, drenagem, e disponibilidade de água para as plantas, necessita do conhecimento da relação entre o conteúdo de água no solo e o potencial matricial, representado pela curva de retenção de água no solo (CRA). No entanto, a determinação da CRA demanda tempo e possui um custo relativo alto. Uma alternativa é sua determinação através de modelos que estimam a CRA a partir de alguns atributos de fácil determinação, chamados funções de pedotransferência (FPT). A finalidade desse trabalho foi quantificar os efeitos da mudança do uso do solo sobre os atributos físicos e hídricos no Sudeste do Estado do Pará. Utilizou-se o banco de dados do Projeto Serviços ecossistêmicos e sustentabilidade das paisagens agrosilvipastoris da Amazônia Oriental, para obter dados de textura (areia, silte e argila), densidade do solo (Ds), carbono orgânico (CO), pH, capacidade de troca de cátions (CTC) e, as vezes, as CRA. Primeiramente, foram avaliadas 16 FPT existentes na literatura; 8 FPT paramétricas, que estimam os parâmetros empíricos do modelo de van Genuchten e 8 FPT pontuais, que estimam a umidade em potenciais específicos de água no solo. Posteriormente, buscando maior capacidade preditiva das FPT, através da técnica de regressão múltipla, desenvolveu-se uma FPT utilizando os atributos do solo mensurados no projeto. As melhores FPT foram utilizadas para estimar os parâmetros do modelo de van Genuchten nos sítios onde não havia CRA medida. Através desta extrapolação, avaliou-se o efeito da mudança de uso do solo sobre a distribuição dos tamanhos de poros, utilizando-se análise de componentes principais (ACP). Dentre as FPT testadas, as que apresentaram melhor resultado foram as FPT propostas por Tomasella et al. (2000), no entanto, a avaliação de desempenho realizada mostrou resultados não satisfatórios. Por outro lado, os resultados apresentados pela FPT desenvolvida neste trabalho alcançaram boa capacidade preditiva dos parâmetros empíricos do modelo de van Genuchten (1980). A ACP possibilitou identificar uma grande variabilidade entre os atributos medidos e estimados dos solos. Devido a esta variabilidade, não foram detectadas diferenças marcantes nos atributos dos solos em função do uso. Para isso, faz-se necessário estudos complementares, aumentando a escala e/ou classes de solo.The understanding of soil water attributes, such as infiltration, drainage, solute movement and water availability for plants, needs the knowledge of the relationship between water content and soil matric potential, represented by the soil water retention curve (SWRC). However, the determination of the SWRC demands considerable time and has a relatively high cost. An alternative is to model its determination using pedotransfer functions (PTF) that calculate the SWRC parameters using easily obtainable soil attributes. The aim of this study was to use PTF to quantify the effects of changing land use on soil hydro-physical attributes at three locations in southern Pará. The database obtained in the project \"Ecosystem services and sustainable agroforestry landscapes in Eastern Amazonia\" was used in order to obtain soil texture data (sand, silt and clay), bulk density (Bd), organic carbon (OC), pH, cation exchange capacity (CEC) and the SWRC. First, 16 PTF found in the literature were evaluated (8 estimating the empirical parameters of the van Genuchten (1980) model and 8 to estimate soil moisture at specific matric potentials). Later, aiming at a greater predictive ability, a PTF was developed using the technique of multiple regression and the soil attributes determined in the project. The best PTF were used to estimate the model parameters of van Genuchten (1980) at the locations where there was no SWRC data. These results were used to determine the changes in pore distribution due to land use using principal component analysis (PCA). These changes were also associated with changes in content of OC and Bd using multivariate analysis. Of the FPT found in the literature the one that showed the best performance was the FPT developed by Tomasella et al. (2000), however, the evaluation performed showed poor results when the data was extrapolated to the locations where no SWRC were determined. The results presented by the FPT developed in this work showed a better efficiency in determining the SWRC in the locations that did not have this information. The PCA analysis performed on this data identified a large variability among the measured and estimated soil attributes. Because of this variability, there were no marked differences in soil attributes depending on land use. For this, more detailed studies are necessary at a increasing scale and/or at the soil class level.
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Amaral, Mayka Danielle Brito. "Monopolização do território e carvoejamento na Amazônia: a produção do carvão vegetal nos assentamentos e acampamentos de reforma agrária e nas carvoeiras tradicionais de Rondon do Pará." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/8/8136/tde-20062012-150427/.
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O presente trabalho versa sobre o processo de monopolização do território pelo capital, materializado nas indústrias siderúrgicas, a partir da atividade de carvoejamento realizada no município de Rondon do Pará, localizado no sudeste do estado do Pará, na Amazônia brasileira. As indústrias siderúrgicas constituem a materialização do capital, caracterizado como desigual, combinado e contraditório, que ao se implantarem na Amazônia promoveram uma relação de subordinação de diversos sujeitos sociais em diferentes municípios, para produzirem o carvão vegetal. Dentre esses municípios, este trabalho destaca a realidade de Rondon do Pará, que produz o carvão vegetal desde o início da produção da siderurgia na Amazônia. Dessa maneira, buscou-se caracterizar e analisar o processo de monopolização do território a partir da atividade de carvoejamento nesse município, onde se verificou que a produção do carvão vegetal tem sido realizada através de relações de produção capitalistas assalariadas, e de relações não-capitalistas camponesas de produção. Além de se produzir carvão da forma tradicional, por meio do reaproveitamento do resíduo de serraria e da pecuária, do desmatamento primário e secundário, essa atividade foi introduzida nos assentamentos e acampamentos rurais de reforma agrária, e tem substituído a produção de alimentos. Dessa forma, notou-se que a monopolização do território pelas indústrias siderúrgicas, a partir da atividade de carvoejamento, é realizada através da apropriação da renda camponesa da terra e da extração da mais-valia, tanto nas carvoeiras tradicionais quanto nas carvoeiras localizadas no interior dos assentamentos e acampamentos rurais de reforma agrária no município de Rondon do Pará.The paper concerns the territory monopolization process by the capital, present in steel industries, starting from the charcoal production that takes place in the city of Rondon do Pará, located southeastern of the state of Pará, in the Brazilian Amazon. The steel industries constitute the capital materialization, considered uneven, combined and contradictory, that when implemented in the Amazon promoted a subordination relationship of several social actors in different cities, for the production of charcoal. Among these cities, this paper emphasizes the reality of Rondon do Pará, which produces charcoal since the beginning of the steel production in the Amazon. Thus, it was sought to characterize and analyze the territory monopolization due to the charcoal production activity in this city, where it was verified that such production has taken place though employment capitalist production relations and rural non-capitalist production relations. In addition to the traditional charcoal production, through reuse of sawmills and livestock waste, and primary and secondary deforestation, this activity has been introduced in the land reform rural settlements and camps and has substituted food production. Thus, the territory monopolization by the steel industries, starting from the charcoal production, takes place through the appropriation of land peasantry income and surplus value extraction, in traditional charcoal production areas as well as in charcoal production areas located in the interior of land reform rural settlements and camps in the city of Rondon do Pará.
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Ganade, Gislene Da Silva. "Seedling establishment in Amazon rain forest and old-fields." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339196.
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Schmall, Susanne. "Das Ökotourismusprogramm der Organización de Pueblos Indígenas de Pastaza (OPIP) im Amazonastiefland Ecuadors." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 1999. http://dx.doi.org/10.18452/14437.
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Die Organización de Pueblos Indígenas de Pastaza (OPIP) wurde 1979 zur Verteidigung der Landrechte der indigenen Völker der Quichuas, Shiwiars und Záparos der Provinz Pastaza im Amazonastiefland von Ecuador gegründet. Anhand der Einzelfallstudie über die OPIP und des Ökotourismusprogramms der OPIP (ÖTP) wird untersucht, ob es einer indigenen Basisorganisation gelingt, selbstbestimmte Entwicklung bei Wahrung der natürlichen Ressourcen in ihrem Territorium durchzusetzen. Aufbau und Entwicklung des ÖTP in zwei Comunidades und zwei Asociaciones wurden durch seine Anbindung an die OPIP behindert, da sich politische und sachliche Kriterien bei der Planung sowie politische und programmspezifische Aufgaben der Beteiligten vermischten. Da das ÖTP sich noch um regelmäßige Einkommen und wirtschaftliche Rentabilität bemüht, sind Maßnahmen zum Ressourcenschutz sowie die dafür notwendige partizipative Planung mit den Comunidades und Asociaciones vernachlässigt worden. Die vorliegende Arbeit kommt zu dem Schluß, daß einkommenschaffende Projekte nicht erfolgreich von indigenen Basisorganisationen als Träger durchgeführt werden können und sie von ihren eigentlichen politischen und entwicklungsstrategischen Aufgaben ablenken. Es gelingt den Organisationen auf diese Weise weder, sich selbst zu finanzieren, noch den Schutz der natürlichen Ressourcen in ihrem Territorium durchzusetzen. Anstatt als Träger von Projekten aufzutreten, sollten sie direkte Kooperationen zwischen Comunidades und Entwicklungsorganisationen vermitteln und deren Erfahrungen zur Formulierung von ökonomischen und ökologischen Leitlinien nutzen. Entwicklungsorganisationen sollten die indigenen Basis-organisationen dementsprechend mit Institutionenförderung, Organisations- und politischer Beratung unterstützen.The Organisation of Indigenous People of Pastaza (OPIP) was founded in 1979 to defend the land rights of the indigenous people Quichua, Shiwiar and Záparo in the province of Pastaza in Ecuador?s Amazonian rainforest. The present case study of the OPIP and its Ecotourism Program answers the question, whether an indigenous grass-roots organisation has the capability to implement self-determined development by conserving the natural resources in its territory. The organisational and institutional reliance of the Program on the OPIP hindered the development process of the Program in four communities. The OPIP interfered with political criteria in the Program and gave some project staff additional political tasks to their program-related functions. With the quest for economic resource management and the essential participatory project planning with the communities has been neglected. The author concludes, that income generating projects can not be succesfully implemented by indigenous organisations as the implementation bodies, and that they divert those organisations from their genuine political and strategic development tasks. The organisations neither achieve auto-financing, nor the conservation of natural resources in their territories. Instead of implementing such projects, indigenous organisations should facilitate the direct cooperation between communities and development organisations, and should use their experiences to formulate economic and ecological strategic goals and steps to achieve them. Development organisiations should support indigenous organisations through institutional strengthening as well as organisational and political assistance.
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Candido, Silvio Eduardo Alvarez. "Comunidades ribeirinhas, engenheiros e conservação da floresta: construção participativa do espaço tecnológico em empreendimentos econômicos solidários na Amazônia." Universidade Federal de São Carlos, 2010. https://repositorio.ufscar.br/handle/ufscar/3638.
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Previous issue date: 2010-06-28Financiadora de Estudos e Projetos
The purpose of this research is to analyse the participatory construction of the technological space of a solidarity economy organization of production and commercialization of Brazil nuts integrated by inhabitants of riverside communities of the Lower Madeira River, in Rondônia. The restore of household extractive economies is one of the proposals of forest peoples social movements to match life quality improvement and environmental conservation. This opposes to the hegemonic model of development of the Amazon Rainforest region, based on technocratic state intervention, which is responsible for the harsh social and environmental crises that hit the region and which has in the expel of.traditional forest people from their home lands one of the most perverse effects. New extractive economies have two features that also oppose the early rubber tapping period. Firstly it is based on democratic work relations, what suggest a connection with solidarity economy movement. On the other hand, it purposes it should incorporate new technologies which would radically improve productive forces, calling for integration with social technology movement. Exploring the existing synergies of these counter-hegemonic movements, the dissertation aims to demonstrate that engineers, technologists and other professionals involved with technological development may assume an important role to merge community strengthen and forest conservation. To do so, the methodology developed by Herrera (1981), alluding to the generation and technology for rural areas, is taken as an important reference. The scope of this method is adapted to be applicable to a solidarity economy organization including extractivists of the Lower Madeira River producing and commercializing Brazil nuts. Recognizing the social character of rational systems, the methodology demands qualified participation of the workers and results in the technological space of the organization, agreed upon the associated producers and the professionals aiming to support them. The experience of the adapted method proved to be effective, pointing out that real engagement of specialists with social transformation demands the capacity of dialoguing with groups which and usually considered irrelevant in the technological development process.
O trabalho busca analisar a construção participativa do espaço tecnológico de um empreendimento econômico solidário de produção e comercialização de castanha da Amazônia formado por moradores de comunidades ribeirinhas do Baixo Rio Madeira, em Rondônia. A revigoração da economia extrativista constitui uma das propostas dos movimentos sociais de populações tradicionais da floresta, buscando compatibilizar a melhoria na qualidade de vida com a conservação ambiental. Contrapõe-se, assim, ao modelo de desenvolvimento baseado na intervenção tecnocrática do Estado, responsável pela instauração da crise socioambiental vivenciada atualmente na região, que tem no violento processo de desterritorialização de comunidades tradicionais, um de seus componentes mais perversos. O novo extrativismo tem duas características fundamentais para sua viabilização e que o diferenciam do extrativismo praticado durante os ciclos da borracha. Primeiramente, ele se baseia em formas democráticas de organização do trabalho, o que sugere o diálogo com o movimento da economia solidária. Além disso, propõe a melhoria da qualidade das forças produtivas por meio da incorporação de novas tecnologias, o que aponta para interação com o movimento da tecnologia social. Ao explorar as sinergias existentes entre esses movimentos contra-hegemônicos, a dissertação busca mostrar que engenheiros, tecnólogos e outros especialistas envolvidos com o desenvolvimento tecnológico podem assumir um papel importante para compatibilizar o fortalecimento das comunidades da floresta e a conservação da Amazônia. Para tanto, toma-se como referência a metodologia desenvolvida por Herrera (1981), voltada para áreas rurais, que foi adaptada para a geração e avaliação de tecnologias em empreendimentos econômicos solidários e aplicada no âmbito da produção e comercialização coletivas de castanha pelos extrativistas do Baixo Madeira. Tal método reconhece o caráter social dos sistemas racionais, demandando a participação qualificada dos produtores e tem como resultado o espaço tecnológico do empreendimento, que corresponde a uma agenda pactuada com os associados para a atuação de profissionais engajados em seu apoio. Sua aplicação junto aos produtores se mostrou eficaz, contribuindo para evidenciar que o efetivo engajamento de especialistas com a transformação social demanda disposição para dialogar com grupos cujas formas de enxergar o mundo e saberes são muitas vezes vistas como irrelevantes no processo de desenvolvimento tecnológico.
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Stafford, Ciara. "Impacts of indigenous communities on the biodiversity of neotropical rainforests." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/impacts-of-indigenous-communities-on-the-biodiversity-of-neotropical-rainforests(613e8c12-bf09-428b-98fc-eacb96845bcf).html.
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This thesis explores how indigenous communities in the neotropics affect the biodiversity of the forests in which they live; and assesses how the culture, preferences and perceptions of communities can influence the outcome of this relationship. This is first investigated via a case study that compares primate populations between a protected area in the Ecuadorian Amazon and a territory in its adjacent buffer zone that is owned by an indigenous Kichwa community. I then use an ethnoprimatological approach to investigate the attitudes of this community to primates, namely looking at (a) whether primates are seen as a distinct group, (b) the relative importance of primates as sources of bushmeat and pets and (c) the perceived value of primates in terms of their value as a resource or their ecological role. I show that diurnal primates are seen as a cohesive group, but that tree-dwelling non-primates including sloths, kinkajous and tamanduas are also frequently classified as 'monkeys'. The community's perceptions of the value of primates are more closely associated with their potential as bushmeat and pets, whereas few respondents view their importance in terms of their role in the forest ecosystem. I compare our findings to those in studies of other indigenous groups and discuss how they could contribute to more effective conservation planning. Next, I assess how hunting preferences for mammals and birds vary across communities over the whole of central America, Amazonia and the Guianan shield. I show that primates, cetartiodactyls and rodents are the mammalian cornerstones of prey provision for hunters in neotropical communities, whereas Galliformes, Tinamiformes, Psittaciformes, Gruiformes, Piciformes are the most commonly hunted bird orders. The location of a community alone is a significant but weak predictor of the structure of its hunting profile in terms of order preferences. In addition, I found no relationship between a community's age and size and the average biomass of birds or mammals hunted, or the number of mammal species that are targeted. I discuss whether the age and size of communities are robust indicators of past and current hunting pressure, as well as the suitability of cross-sectional data for monitoring large-scale hunting patterns.
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Souza, Viviane Figueiredo. "Mecanismos da ciclagem do nitrogênio e emissão de óxido nitroso (N2O) em solos de diferentes latitudes." Niterói, 2017. https://app.uff.br/riuff/handle/1/4407.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ
O nitrogênio (N) é um elemento imprescindível para todos os organismos do nosso planeta, entretanto o composto nitrogenado mais abundante, o gás dinitrogênio (N2), é assimilável apenas por poucos micro-organismos. Isso torna o N limitante, refletindo na sua disponibilização via mineralização de matéria orgânica (MO) e a nitrificação, que produzem amônio (NH4+) e nitrato (NO3-), respectivamente. Em solos, esses processos são regulados por fatores como conteúdo de MO e água no solo, pH e temperatura. Em ecossistemas florestais, tropicais e boreais, esses processos são muito relevantes e ainda pouco estudados, principalmente em áreas de floresta secundária sob influência de manejo. A mudança de uso do solo causa alterações na ciclagem e disponibilidade do N, nos fatores reguladores, e na emissão de óxido nitroso (N2O), um gás de efeito estufa. Padrões de recuperação florestal são bastante distintos entre diferentes florestas tropicais, como visto para floresta de Mata Atlântica e Amazônica, com taxas de mineralização em florestas jovens (10 anos) muito elevadas na Amazônia (20,9 μg N g-1 SWD d-1) e mais baixas na Mata Atlântica (3,2 μg N g-1 SWD d-1). Já a nitrificação teve um padrão semelhante, com baixas taxas em ambas as florestas jovens (0,6 6,8 μg N g-1 SWD d-1 na Mata Atlântica e Amazônia, respectivamente), o que indica uma ciclagem de N conservativa, evitando perdas via emissão de gás e lixiviação de NO3-. Entretanto, a emissão de N2O em área de restauração na Mata Atlântica foi maior do que na pristina (22 e 2,5 μg N2O-N g-1 SWD h-1, respectivamente) devido à maior temperatura do solo que estimula os processos microbianos produtores de N2O. Em termos de floresta pristina, a taxa de nitrificação foi bastante distinta entre a floresta de Mata Atlântica e Amazônica (0,08 e 15,9 μg N2O-N g-1 SWD h-1, respectivamente). Isso evidencia os diferentes fatores reguladores de cada região tropical, como regime de chuvas, composição vegetal, tipos de solo, etc. Em florestas boreais, foi visto que o conteúdo de MO e água do solo e o pH do solo são os principais reguladores, limitando a disponibilidade de N em florestas bem drenadas dominadas por coníferas, em comparação com florestas pouco drenadas dominadas por turfa. Dessa forma, verificamos que a mineralização e, principalmente, a nitrificação, são processos muito relevantes no controle de N, e mesmo em ecossistemas diferentes, os fatores reguladores muitas vezes são os mesmos. Isso evidencia a necessidade de mais estudos acerca da dinâmica do N nesses ambientes, principalmente em florestas em restauração
Nitrogen (N) is an essential element for all organisms; however, the most abundant nitrogen compound, dinitrogen (N2), is assimilable only by a few microorganisms. This makes N limiting, which reflects in its availability via organic matter (OM) mineralization and nitrification, which produce ammonium (NH4+) and nitrate (NO3-), respectively. In soils, these processes are regulated by factors such as OM and soil water content, pH and temperature. In forest ecosystems, tropical and boreal, these processes are very relevant and still poorly understood, especially in secondary forest previously deforested. The land use change causes alterations in cycling and availability of N, regulating factors, and emission of nitrous oxide (N2O), a greenhouse gas. Forest recovery patterns are quite distinct among different rainforests, as seen for Atlantic and Amazon rainforest, with very high levels of mineralization in young forests (10 years) in Amazonia (20.9 μg N2O-N g-1 SWD h-1) and low in the Atlantic Forest (3.2 μg N2O-N g-1 SWD h-1). Nitrification had a similar pattern between them, with low rates in both young forests (0.6 and 6.8 μg N2O-N g-1 SWD h-1 in the Atlantic and Amazon forest, respectively), indicating a conservative N cycling, avoiding losses through gas emission and NO3- leaching. However, the N2O emission in restoration area in the Atlantic Forest was higher than in pristine (22 and 2.5 μg N2O-N g-1 SWD h-1, respectively) due to the higher soil temperature, which stimulates microbial production of N2O. In terms of pristine forest, the nitrification rate was very different between the Atlantic forest and Amazonian forest (0.08 and 15.9 μg N2O-N g-1 SWD h-1, respectively), showing the different regulatory factors of each tropical region, such as rainfall regime, vegetal composition, soil types, etc. In boreal forests, OM, soil water content and soil pH were the main regulators, limiting the availability of N in conifer-dominated well-drained forests compared to peat-dominated poorly drained forests. In this way, we verified that mineralization and, mainly, nitrification are very relevant processes in the control of N, and even in extremely different ecosystems, the regulating factors are often the same. This evidences the need for more studies about N dynamics in these environments, especially in restoration forests
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Metcalfe, P. R. "The late Quaternary history of the rainforest-savanna boundary in SW Amazonia." Thesis, Swansea University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638185.
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This research assesses how forest-savanna boundaries have shifted in response to past environmental changes, which is crucial to understanding the present-day vegetation mosaic and the origins of Amazon biodiversity as a whole. Individual plant leaf-wax compounds can be extracted from lake sediments and their isotopic values measured by compound-specific 13C analysis, permitting the evaluation of past changes in the abundance of C3 and C4 graminoids, and thereby clarify ambiguities in the pollen record. In this study, a multiproxy approach, using grass-cuticle assemblages and stable carbon-isotope analyses of total organic carbon, is being applied to a lake-sediment core from Laguna Chaplin (14o28’S, 61o04’W), situated in Noel Kempff Mercado National Park (which straddles a climatic transition zone between Amazonian moist evergreen forest, semi-deciduous forest, and savanna). The δ13C values of TOC ranged from 17% at the LGM to 26% in the late Holocene, suggesting an increased representation of C4 graminoids during glacial times. This finding is consistent with the corresponding glacial-age uncharred fossil cuticle coverages of Salviniaceae as well as pollen assemblages, which are dominated by grasses and palms (Mauritia/Mauritiella) with low levels of rainforest taxa, implying an expansion of seasonally-flooded savannas at the expense of seasonally-flooded forest. Compound-specific 13C analyses of leaf-wax n-alkanes and n-alkanoic acids show a dominance of algal and aquatic macrophytes biomarkers in the last glacial period lending additional support to this inference. The palaeoecological inferences previously made from pollen and bulk carbon-isotope data will be tested using these results, permitting overall conclusions to be drawn at much greater taxonomic resolution.
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Germer, Sonja. "Near-surface hydrology and hydrochemistry under contrasting land-cover." Phd thesis, Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/1904/.
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Human transformation of the Earth’s land surface has far-reaching and important consequences for the functioning of hydrological and hydrochemical processes in watersheds. In nowadays land-use change from forest to pasture is a major issue in particular in the tropics. A sustainable management of deforested areas requires an in-depth understanding of the water and nutrient cycle. On this basis we compared the involved hydrological pathways for rainfall to reach streams and the nutrient budgets of a tropical rainforest and a pasture. In addition we studied the links of hydrochemical differences to differences of the relative importance of flowpaths. This study was conducted in the southwestern part of the Brazilian Amazon basin. An intensive hydrological and hydrochemical sampling and monitoring network was set up. The results indicate that the hydrology was modified in many ways due to land-use change. The most important alteration was the increased importance of the fast flowpath overland flow. Solute exports were in particular linked to the increased volume of overland flow that resulted from the land-use change. An additional reason for the increased nutrient exports from the pasture are the high concentrations of these nutrients in pasture overland flow probably as a due to cattle excrements. Tight nutrient cycles with minimal nutrient losses could not be maintained after the land-use change. This study provides the first attempt to quantify the respective nutrient losses.Die Zerstörung von natürlicher Vegetation kann weit reichende Folgen auf den Wasser- und Nährstoffhaushalt von Ökosystemen haben. Der Landnutzungswandel vom Wald zur Weide ist heute in den Tropen ein wichtiges Thema. Eine nachhaltige Nutzung abgeholzter Gebiete setzt ein fundiertes Wissen des Wasser- und Nährstoffhaushaltes voraus. Darauf aufbauend wurden in dieser Studie das Abflussverhalten und die Nährstoffbilanzen von einem tropischem Regenwald und einer Weide verglichen. Außerdem wurde untersucht inwieweit die Nährstoffbilanzen vom Abflussverhalten abhängen. Die Untersuchungsgebiete liegen im südwestlichen brasilianischen Amazonasgebiet. Ein umfangreiches System zur Aufnahme von hydrologischen Daten und zum Sammeln von Wasserproben wurde aufgebaut. Die Ergebnisse haben gezeigt, dass sich das Abflussverhalten durch die Landnutzung geändert hat. Die wichtigste Änderung vom Wald zur Weide war der gesteigerte Anteil des schnellen Wasserabflusses auf der Geländeoberfläche. Hieraus resultierten gesteigerte Nährstoffausträge aus der Weide gegenüber dem Wald. Ein weiterer Grund für die gesteigerten Nährstoffausträge sind die hohen Konzentrationen dieser Stoffe im Oberflächenabfluss der Weide, die vermutlich mit den Ausscheidungen des Viehs zusammenhängen. Es hat sich also gezeigt, dass der quasi-geschlossene Nährstoffkreislauf nach der Landnutzungsänderung nicht aufrecht erhalten werden konnte. Diese Arbeit liefert den ersten Versuch diese Nährstoffverluste zur quantifizieren.
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Lamarca, Junior Mariano Rua. "O valor econômico do carbono emitido pelo processo de desmatamento da Amazônia como instrumento de conservação florestal." Pontifícia Universidade Católica de São Paulo, 2007. https://tede2.pucsp.br/handle/handle/9317.
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Previous issue date: 2007-09-27We analyse in the this work the causes of deforestation of the Legal Amazonia and the environment subject present in the public policies for the region, including the Public Forests Management Law (Law 11.284/06), approved with the goal of regulating public forests management in Brazil and promoting the sustainable development. We discuss the Kyoto Protocol´s Clean Development Mechanism (CDM) problem regarding forest conservation. Through a hypothetical scenario of zero deforestation and 100% of the not emitted carbon linked to forest conservation projects, we calculate that an economic revenue equivalent to the logging activities could be obtained, contributing to the maintenance of the climatic equilibrium because of the reduced Greenhouse Gases emissions, as well as keeping preserved the biodiversity and environment services values related to the standing forest. Nevertheless, appropriate regulations should be planned and implemented to achieve the desired goal, and the solution proposed in this work is in the convergence of the international laws regulating carbon markets and the native tropical forests protection laws
Analisamos neste trabalho as causas de desmatamento da Amazônia Legal e a questão ambiental presente nas políticas públicas para a região, incluindo a Lei de Gestão de Florestas Públicas (Lei 11.284/06), sancionada com o objetivo de regulamentar a gestão de florestas públicas no Brasil e promover o desenvolvimento sustentável. Discutimos o problema do Mecanismo de Desenvolvimento Limpo (MDL) do Protocolo de Kyoto na questão da conservação florestal. Através de um cenário hipotético de desmatamento zero e 100% do carbono não emitido vinculado a projetos de conservação florestal, calculamos que uma receita econômica equivalente à da exploração madeireira poderia ser obtida, contribuindo para a manutenção do equilíbrio climático pela reduzida emissão de Gases de Efeito Estufa, bem como mantendo preservados os valores da biodiversidade e dos serviços ambientais relacionados à floresta em pé (não derrubada). Entretanto, marcos regulatórios adequados devem ser planejados e implementados para atingir o objetivo desejado, e a solução proposta neste trabalho situa-se na convergência das leis internacionais de regulação dos mercados de carbono e das leis de proteção das florestas tropicais nativas
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Tra, Bi Zamblé Mathieu. "Polyphonie sur les médias socionumériques : le cas des interactions sur YouTube à propos des feux de forêt d’Amazonie." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCC002.
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Cette étude examine l'énonciation polyphonique dans les écrits en ligne, en se focalisant sur celle issue et induite par les interactions sur YouTube lors des feux de forêt en Amazonie. Après une présentation du contexte et des concepts et théories liés à la polyphonie, elle propose un ensemble méthodologique d’analyse de la polyphonie qui permet de saisir d’abord la place des aspects techno-sémiotiques, socioéconomiques, et psychosociologiques de YouTube dans la polyphonie, puis d’interroger cette polyphonie au niveau des autres acteurs médiatiques cités à partir de YouTube. Nous arrivons ainsi à identifier des constances et des changements de configurations polyphoniques au cours de notre période d'observation et à montrer comment ces configurations polyphoniques pendant les feux de forêt d’Amazonie pouvaient être influencées par des variables contextuelles exogènes. Nous constatons aussi des enjeux de pouvoir quand cette polyphonie est utilisée comme stratégie par différents acteurs impliqués dans la controverse sociale autour des feux de forêt d'Amazonie. Cette étude vient compléter les travaux sur l’énonciation éditoriale dans les écrits d’écran en prenant en compte la polyphonie tant au niveau des acteurs en réseau que celle au niveau de l’argumentationThis study examines polyphonic enunciation in online writings, focusing on that which arises from and is induced by interactions on YouTube during the Amazon rainforest wildfires. After presenting the context and the concepts and theories related to polyphony, it proposes a methodological framework for analyzing polyphony that first captures the role of techno-semiotic, socio-economic, and psychosociological aspects of YouTube in polyphony, and then interrogates this polyphony at the level of other media actors mentioned from YouTube. This allows us to identify consistencies and changes in polyphonic configurations during our observation period and to show how these polyphonic configurations during the Amazon rainforest wildfires could be influenced by exogenous contextual variables. We also observe power dynamics when this polyphony is used as a strategy by various media actors involved in the social controversy surrounding the Amazon rainforest wildfires. This study complements previous research on editorial enunciation in screen writings by considering polyphony at both the network actors’ level and the argumentation level
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Araujo, Vieira de Andrade Terence Keller. "La mise en tourisme dans la Haute Amazonie brésilienne. Une approche géographique." Thesis, Paris 3, 2012. http://www.theses.fr/2012PA030169.
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La thèse que nous proposons part de l’idée que questionner la dimension spatiale du phénomène touristique serait une forme de compréhension des transformations des lieux géographiques et des sociétés qui les entourent. Concentrer le regard dans la haute Amazonie brésilienne, nous révèle un des biomes le plus diversifié, complexe et attractif pour la curiosité humaine et qui est en même temps la région avec le moins de flux touristiques du Brésil. Un tel paradoxe nous oblige à analyser cette partie du globe pour ses spécificités, mais faisant aussi partie d’un tout et cela nous conduit à adopter une approche systémique du tourisme. La mise en tourisme des lieux amazoniens sera le focus du système que nous étudions en essayant de comprendre comment les acteurs de la haute Amazonie brésilienne interagissent pour y faire des lieux touristiques. Ainsi deux questionnements majeurs seront le focus à suivre tout au long de notre raisonnement. Premièrement, comment les lieux amazoniens sont-ils devenus touristiques au fil du temps ? et deuxièmement, comment les actions des acteurs stimulent-elles la transformation des lieux touristiques amazoniens ? Pour cela nous proposons une lecture empirique et pragmatique du phénomène touristique fondé sur différentes échelles géographiques. Le regard multiple sur les intentions des populations locales, des flux de voyageurs, ainsi que celles menées par les acteurs politiques et économiques, nous emmène à penser en termes de dynamiques spatiales une spécificité géographique : l’organisation d’un espace peu structuré, à baisse densité démographique, avec une forte présence de ressources socio-environnementales et en voie d´insertion dans un espace touristique mondialThe thesis that we propose starts from the idea that questioning of the spatial dimension of tourism would be a way to understanding the transformations of the geographical places and societies that surround them. Concentrating the focus on the upper Brazilian Amazon, reveals us one of the most diversified, complex and attractive biome for the human curiosity, and which is also the region with the least touristic flows of Brazil. This paradox forces us to analyze this part of the globe for its specificities, but as it is also a part of a whole, we are led to adopt a systematic approach of the tourism. Our goal will be to analyze interactions between different actors of the upper Brazilian Amazon and it creates touristic places. Thus, two major questionings will be the guideline to follow throughout our reasoning. Firstly, how did the Amazonian places become touristic over the time? and secondly, how the actions of the actors stimulate the transformation of the Amazonian touristic places? This is the reason why we propose an empirical and pragmatic reading of the tourist phenomenon based on different geographical scales. Changing the distance and the angle of the observation will be the method used to confront the various representations of the actors around the tourism development. The multiple view on the intentions of the local populations, travelers' flows, as well as those led by the politics and economics actors, makes us think about the geographical specificities: the organization of an unstructured space, with lower population density, but with a strong presence of social and environmental resources and in the process of integration into a world tourist space
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Barrenechea, May. "A REPERCUSSÃO DAS INICIATIVAS DO GOVERNO BRASILEIRO PARA A PROTECÇÃO DA AMAZÓNIA NA IMPRENSA SUECA ONLINE DURANTE O GOVERNO DE LULA." Thesis, Stockholms universitet, Institutionen för spanska, portugisiska och latinamerikastudier, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-75928.
Full textAbstract:
A problemática ambiental no mundo é um tema de suma importância na atualidade. Devido ao incremento do efeito estufa, as mudanças climáticas têm despertado grandes reações no mundo em todas as esferas. Para isso, a Amazónia cumpre um papel decisivo na salvação do planeta e portanto é imprescindível a proteção da mesma. A implementação de uma série de medidas legais do governo brasileiro é fundamental para consegui-la. Este trabalho enfoca a importância global e internacional do assunto, analisando o impacto das iniciativas do governo brasileiro na imprensa sueca versão online. O objetivo deste trabalho é deduzir qual imagem da problemática ambiental amazónica brasileira, das políticas ecológicas brasileiras na Amazónia e indiretamente do Brasil no geral se transmite potencialmente ao leitor sueco. A conclusão obtida concorda com a hipótese que os jornais falam, em pequena escala, sobre o tema ambiental na Amazónia brasileira e sobre as políticas ecológicas brasileiras para a proteção da floresta amazónica.Environmental issues are receiving more and more media exposure today than ever before. What was first a healthy interest amongst people, has led to serious concerns when one takes into account the repercussions that the greenhouse effect is having on the environment. The increased environmental awareness that now exists amongst an ever growing section of the world’s population, has resulted in politicians having to start to take action as there is now a political will to do so. Brazil has the largest mass of tropical rainforest in the world and its protection is of interest to the Brazilian government, the citizens of Brazil and to the inhabitants of the world. A series of legal action measures have been initiated by the Brazilian government to preserve the wellbeing of the rainforest. This thesis examines how and what the Swedish online news providers have reported these measures during the Lula period of administration. The objective of this thesis is to understand how the Brazilian government’s measures have been perceived by the Swedish online news providers and thus by the reading population. Specifically, the focus is on measures taken by the Brazilian government with regards to Brazilian environmental problems in the Amazon rainforest, Brazilian ecological policy in the Amazonia and how all of this in turn leads to better protection of the Amazon rainforest. The data obtained supports the hypothesis that out of all the Brazilian related articles published by the Swedish online news providers, only a small percentage of the total amount of articles are relating to environmental issues in the Brazilian Amazon rainforest and/or the Brazilian environmental politics to protect the Amazon rainforest.
Miljöproblematiken i världen är en mycket viktig fråga. Den ökande växthuseffektens förändringar på klimatet har väckt stora reaktioner överallt i världen på alla områden. Miljömässigt spelar Amazonas regnskog en avgörande roll i att rädda planeten. Därför är det nödvändigt att skydda Amazonas regnskog. Genomförandet av en rad rättsliga åtgärder från den brasilianska regeringen är avgörande för skyddet av den brasilianska regnskogen. Den brasilianska regeringen har genom lagstiftning försökt att vidta nödvändiga åtgärder för att skydda Amazonas regnskog. Denna studie fokuserar på den internationella betydelsen av ämnet och analyserar hur den svenska pressens internetupplagor behandlar den brasilianska regeringens ansträngningar. Huvudsyftet med detta arbete är att få en uppfattning om hur den brasilianska miljöproblematiken i Amazonas regnskog, lagstiftningen runt densamma samt indirekt Brasilien, förmedlas till den svenska tidningsläsaren. Slutsatsen överensstämmer med hypotesen att tidningarna endast skriver kortfattat om miljöfrågor relaterade till den brasilianska regnskogen i Amazonas och den brasilianska miljöpolitikens insatser för att skydda Amazonas regnskog.