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O projeto BIOTA “Diversidade, dinâmica e conservação de florestas do Estado de São Paulo: 40 ha de parcelas permanentes” vem sendo conduzido para o conhecimento dos processos geradores, mantenedores e reguladores da biodiversidade nas principais formações vegetacionais do Estado. Uma parcela permanente de 10 ha foi instalada na unidade de conservação correspondente à Floresta Ombrófila Densa (Mata Atlântica) para a caracterização completa do ecossistema. A investigação de elementos químicos nesse ecossistema altamente ameaçado foi desenvolvida nesta Tese de Doutoramento. Diversos processos são responsáveis pela manutenção de ecossistemas naturais. À ciclagem mineral corresponde o caminhamento dos elementos químicos, que fluem entre os compartimentos bióticos (folha e serrapilheira) e abióticos (atmosfera e solo). A complexidade desse mecanismo regulatório está relacionada com a deficiência, a toxicidade, a fitodisponibilidade e as interações dos elementos químicos, além das condições ambientais de crescimento como luminosidade, temperatura e umidade. Devido à sua adaptabilidade, as plantas absorvem elementos químicos, acumulando-os nos seus tecidos. A acumulação é ativa, ou seja, independentemente do meio, as plantas mantêm as concentrações de determinados elementos. Essa característica corrobora o uso desses organismos para a quantificação da qualidade do ambiente a partir dos estudos de biomonitoração de poluição atmosférica. A análise por ativação neutrônica instrumental – INAA foi a técnica analítica empregada para a biomonitoração devido ao seu nível metrológico elevado e sua capacidade de determinação simultânea de diversos elementos. Para a comparabilidade dos resultados gerados, a qualidade do procedimento analítico, a representatividade das amostras e o efeito da contaminação com particulados de terra aderida à superfície das folhas foram também estudados. Os compartimentos solo, serrapilheira e folha tiveram sua composição química avaliada por INAA. De modo geral, foram detectadas concentrações totais de elementos químicos mais elevadas nos solos de vales (baixa altitude) do que nas regiões de alta altitude (solos mais desenvolvidos). Essa variabilidade não foi determinante das concentrações encontradas nas folhas, indicando a composição química elementar intrínseca das plantas. As concentrações nas folhas também não se alteraram significativamente (nível de 95% de confiança) de acordo com os resultados provenientes de quatro épocas de coleta diferenciadas. Foram identificadas espécies acumuladoras dos nutrientes Ca, Co, K, Na, Se e Zn, dos elementos traços Br, Ba, Cs, Hg, Rb, Sc, Sr e dos lantanídeos Ce, La e Sm. A utilização das espécies arbóreas para a biomonitoração da parcela permanente proporcionou o conhecimento das concentrações naturais dos elementos químicos. O trecho de Mata Atlântica avaliado foi considerado de baixo nível de poluição, pois a maior parte das espécies estudadas apresentou concentrações dos elementos químicos dentro da faixa esperada, com exceção das espécies naturalmente acumuladoras. Elementos traços como As, Cd, Cr e Ni ficaram abaixo dos limites de detecção. O trabalho concentrou esforços para o estabelecimento de padrões de referência para estudos de impacto ambiental considerando a composição química da parcela permanente da Mata Atlântica. O reservatório de elementos químicos no ecossistema foi estimado, evidenciando-se a importância desse conhecimento para a conservação da biodiversidade. / The BIOTA Project “Diversity, dynamic and conservation of forests from the São Paulo State: 40 ha of permanent parcels” has been conducted to provide the knowledge on the generation, sustainability and regulation processes of the biodiversity of the State. A long-term plot (permanent parcel) was installed in the conservation unit corresponding to the Dense Ombrophilous Forest (Atlantic Forest) for the environmental characterization of the ecosystem. The investigation of chemical elements in this highly threatened forest was performed in this Doctorate Thesis. Several processes are responsible for the sustainability of the natural ecosystems. Mineral cycling defines the pathway of chemical elements from non-biotic compartments (soil and atmosphere) to biotic compartments (leaf and litter). The complexity of this regulatory mechanism is related to the deficiency, toxicity, phytoavailability and the interactions of the chemical elements, in addition to environmental growth conditions like luminosity, temperature and humidity. Due to its adaptability, plants are able to uptake and accumulate chemical elements in their tissues. This accumulation is an active process in which the plants tend to maintain the concentrations of some chemical elements independently of the environmental conditions. Such characteristic corroborates the use of these organisms for quantifying the environmental quality by biomonitoring studies of atmospheric pollution. Instrumental neutron activation analysis – INAA was the analytical technique employed for biomonitoring due to its high metrological level and its capability for simultaneous determination of several chemical elements. For the comparability of the results, the quality of analytical procedure, the representativeness of samples and the effect of contamination with earth particles adhered to the leaf surface were also studied. The chemical composition of the soil, litter and leaf compartments was evaluated by INAA. The concentrations of some elements were higher for the soils of the valleys and considerably lower for the soils at higher altitudes. Such variability was not observed for the concentrations found in leaves, indicating the intrinsic chemical composition in plants. The concentrations in leaf did not change significantly (at the 95% confidence level) as demonstrated by the results from four different periods of sampling. Some tree species were able to accumulate the nutrients Ca, Co, K, Na, Se and Zn, the trace elements Br, Ba, Cs, Rb, Sc and Sr and the lanthanides Ce, Eu, La, Sm, Tb and Yb. The use of plants species for biomonitoring the long-term plot provided knowledge on the background concentrations of chemical elements. The Atlantic Forest can be considered to have a low status of pollution since most plants have shown concentrations within the expected range with exception of the accumulator species. Concentrations of some trace elements like As, Cd, Cr and Ni were below the detection limits. This work concentrated efforts to establish reference standards for studies on environmental impact considering the chemical composition in the long-term plot of the Atlantic Forest. The reservoir of chemical elements in the ecosystem was estimated, evidencing the importance of such knowledge for the biodiversity conservation.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-10-24T16:58:28Z No. of bitstreams: 1 DanielCabralTeixeira.pdf: 2770074 bytes, checksum: 0d0c1bc812ba890678e907aec3eab6b6 (MD5) / Made available in DSpace on 2017-10-24T16:58:28Z (GMT). No. of bitstreams: 1 DanielCabralTeixeira.pdf: 2770074 bytes, checksum: 0d0c1bc812ba890678e907aec3eab6b6 (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / A Mata Atlântica, um hotspot mundial com grande diversidade de plantas e animais, está localizado na região mais industrializada do Brasil, uma fonte em potencial de elementos químicos para a atmosfera. Recentemente, foi descrito a entrada de Hg via serapilheira para o solo principalmente, após a captação estomática (poros foliares), agindo como via importante para o transporte deste poluente do ar para o solo durante o seu ciclo biogeoquímico. Este fluxo de mercúrio é mais evidente em florestas tropicais, que apresentam as maiores produções de serapilheira. O objetivo deste trabalho foi quantificar a concentração total do Hg na serapilheira, e estimar sua deposição no Parque Estadual da Pedra Branca, na cidade do Rio de Janeiro, durante o período de um ano. Foram analizadas, folhas de cinco espécies dominantes, para se avaliar a concentração de Hg nas folhas do dossel e testar as correlações com os parâmetros anatômicos foliares, tais como as freqüências estomáticas e tricomáticas. A média anual da concentração de Hg foi de 237+ 52 ng g-1 e o fluxo de 184 + 98 μg m-2 sobre uma produção de serapilheira de 7,6 t.ha-1. A concentração mensal de Hg variou de acordo com a temperatura de dois meses anteriores. A precipitação mensal teve uma forte correlação negativa com as concentrações de Hg somente durante os meses de altas temperaturas. Estas correlações confirmam a dependência com os eventos fisiológicos, controlados por processos bioquímicos que definem a abertura estomática, sendo mais eficiente durante altas temperaturas e solo sem deficiência hídrica. A concentração de Hg na folhagem do dossel revelou uma grande variação interespecífica de 60 ng g-1 em Metternichia príncipes; 84 ng g-1em Colubrina. glandulosa; 170 ng g-1 em Cordia trichotoma; 190 ng g-1 em Piptadenia gonoacantha; até 215 ng g-1 em Alchornea iricurana.. Uma correlação positiva ocorreu entre as concentrações de Hg e a densidade estomática, exceto pelas espécies com tricomas, demonstrando mais uma evidência da captação estomática e possível papel da adsorção superficial dos tricomas. Estes valores elevados, mesmo para áreas urbanas poluídas, mostram a complexidade dos fenômenos climáticos e fisiológicos que regem a captação de Hg em florestas tropicais. Esta captação potencial da Mata Atlântica deve ser considerada para sua conservação e preservação, uma vez que o destino do Hg, vindo da serapilheira, no solo é desconhecido. Devido ao status de poluente global do Hg, o desenvolvimento de leis internacionais para emissões atmosféricas de Hg, é crucial. / The Atlantic Forest, a hotspot in the world with a great diversity of plants and animals, is located in the most industrialized region of Brazil, a potential source of chemical elements for the atmosphere. Recently, was described the Hg litterfall input to the soil mainly, after the stomatal (leaf pores) uptake, acting as an important way to transport this pollutant from air to soil. This flux of mercury is more notable in tropical forests, which have the higher annual litter production. The aim of this work was quantify the total concentration of Hg in litterfall, and estimate how much was deposited in the Parque Estadual da Pedra Branca, na cidade do Rio de Janeiro. Leaves of the five most predominant species were analyzed to assess the Hg concentrations by canopy leaves and test the correlations with foliar anatomical parameters, such as stomatal and trichomatic frequency. The annual mean of Hg concentration was 237, 7+ 52 ng g-1 and the flux was 184, 2 + 98 μg m-2 over a 7,6 t.ha-1 of litter production. The past two months temperature was correlated to the monthly concentration deviation, showing the relation with biochemistry process ruling the plant growing. The monthly precipitation had a strong negative correlation with the Hg concentrations of the higher temperature months. These correlations confirm the dependency on physiological events, controlled by biochemistry processes that rule the stomatal opening, being optimal during high temperatures and soil with no water deficiency. The green foliage Hg concentration revealed a great interespecific variation, from 60 ng g-1 - Metternichia principes, 84 ng g-1 - Colubrina. glandulosa,170 ng g-1 - Cordia trichotoma, 190 ng g-1 - Piptadenia gonoacantha to 215 ng g-1 - Alchornea iricurana. There was a clear positive correlation between these concentrations and the stomatal density of these species, except by the species with trichomes, showing one more evidence of the stomatal uptake and the superficial trichomes adsorption roles. These results are very high even to a polluted urban area, and show the complexity of phenological and climatic phenomena that rules the Hg uptake in tropical forests. This potential uptake of Mata Atlantica must be considered for their conservation and preservation, once the Hg soil destination came from litter, is unknown. Due to the global Hg pollutant status, the development of international laws, to Hg air emissions, is crucial.

Made available in DSpace on 2017-07-10T19:23:48Z (GMT). No. of bitstreams: 1 Larissa_ Kummer.pdf: 3836984 bytes, checksum: 1746a7b3c060c75c722565a4bf452739 (MD5) Previous issue date: 2014-02-21 / High concentrations of heavy metals in the soil can affect the sustainability of ecosystems and the health of humans and animals. The metal availability in the environment is related to the characteristics of each element, historical and source of contamination, as well as the properties of each soil. The presence of more than one element is common in contaminated areas and their interaction can affect their behavior in the environment. Researches have been developed to study the behavior of metals in different types of soils and thus help in cases of remediation. In recent years, the soil washing with biosurfactant has been presented as a promising method of remediation with little or no effect on the physico-chemical and microbiological characteristics of the soil, but the costs of obtaining this biosurfactant are still high, because most manufacturers use artificial means for production. Thus, this study had the objective of evaluating the remediation potential of the biosurfactant obtained from the fermentation of cassava water through the action of the bacteria Bacillus subtilis. This biosurfactant was characterized as surfactin, an anionic lipopeptide. Soils of different origins were used, one of them typical of the southwestern state of Paraná and the other from the northwest. The soils were first evaluated according to their potential for adsorption of the elements copper, zinc and lead in monometallic and multimetalic conditions, representing non-competitive and competitive conditions respectively. This evaluation was carried out by tests of adsorption and application of the matematical models of Langmuir and Freündlich. Soils were characterized chemically, physically and mineralogically. After that, it was performed the process of artificial contamination of these soils for application in the experiments of soil washing with biosurfactant in different conditions, having pH and concentration of biosurfactant solution as the main variables. Furthermore, it was also assessed the adsorption s capacity for metals by biosurfactant in liquid medium. The results showed that metals have different behaviors related to the adsorption and desorption to soil and to the biosurfactant. The soil type is also very important for the efficiency of metal removal. The clay soil showed higher adsorption capacity and therefore lower capacity of metal removal when compared to the sandy soil. In general, the soils showed the following sequence of adsorption capacity: Pb > Cu > Zn. The Pb was the element that less desorved by the washing process. It can also be concluded that, when soils are contaminated by more than one element at the same time, its ability to leach is greater than when the element is alone in the medium. This situation occurs because of differences between the competitive processes that take place in the active sites. The washing experiments showed that the biosurfactant was not able to improve the efficiency of removal of metals. The results obtained by the control treatments (only pure water) had very similar values to those that contained biosurfactant. When the wash solution containing the biosurfactant was in high concentrations, decrease in removel efficiency was found in some of the samples. Analysis of high performance liquid chromatography showed that the biosurfactant was adsorbed to soil samples, which is the consequence of not observing the effectiveness of the extractor in the removal of metals. It is notable, however, that the surfactin obtained has the potential to bind to metals, since the tests of adsorption to metals was confirmed by experiments. According to the results obtained, it can be inferred that the surfactin has greater potential for metal removal in liquid media than in solid medium, because of the lower possibility of adsorption. In soil, the results indicated potential use of this biosurfactant as stabilizing of metals in methods of remediation "in situ". / Concentrações elevadas de metais pesados no solo podem afetar a sustentabilidade dos ecossistemas e também a saúde dos seres humanos e animais. A disponibilidade do metal no ambiente está relacionada às características de cada elemento, histórico e fonte de contaminação, bem como às propriedades de cada solo. A presença de mais de um elemento em áreas contaminadas é comum e a interação entre eles pode afetar o seu comportamento no ambiente. Diante do problema, pesquisas vêm sendo realizadas a fim de estudar o comportamento dos metais em diferentes tipos de solos e assim auxiliar nos procesos de remediação. Nos últimos anos, a lavagem do solo com biossurfactante tem sido apresentada como um método promissor de remediação com pequeno ou nenhum efeito sobre as características físico-químicas e microbiológicas do solo, porém os custos de obtenção deste biossurfactante ainda são altos, pois a maioria dos fabricantes utiliza meios artificiais para sua produção. Neste sentido, este trabalho teve como objetivo geral avaliar o potencial de remediação do biossurfactante obtido a partir do bioprocessamento da manipueira pela ação de bactérias Bacillus subtilis. Este biossurfactante foi caracterizado como surfactina, um lipopeptídeo aniônico. Foram utilizados solos de origens distintas, sendo um deles típico da região sudoeste do estado do Paraná e outro da região noroeste. Os solos utilizados foram primeiramente avaliados de acordo com o seu potencial de adsorção dos elementos cobre, zinco e chumbo em condições monometálicas e multimetálicas, representando condições não-competitivas e competitivas, respectivamente. Esta avaliação foi feita por meio de testes de adsorção e aplicação de modelos matemáticos de Langmuir e Freündlich. Os solos foram caracterizados química, física e mineralogicamente. A partir de então realizou-se o processo de contaminação artificial destes solos para posterior aplicação dos experimentos de lavagem com o biossurfactante em diferentes condições, sendo as variáveis pH e concentração da solução de biossurfactante como as principais. Além disso, também foi avaliada a capacidade de adsorção dos metais pelo próprio biossurfactante, em meio líquido. Os resultados mostraram que os metais apresentam comportamentos distintos quanto a adsorção e dessorção ao solo e ao biossurfactante. O tipo de solo também é muito importante para a avaliação da eficiência de remoção de metais. O solo argiloso apresentou maior capacidade de adsorção e consequentemente menor capacidade de remoção dos metais quando comparado ao solo arenoso. De modo geral, os solos apresentaram a seguinte sequência de capacidade de adsorção: Pb > Cu > Zn. O Pb foi o elemento que menos dessorveu pelos processos de lavagem. Foi possível também concluir que quando os solos estão contaminados por mais de um elemento ao mesmo tempo, a capacidade de lixiviar-se é maior do que quando o elemento está sozinho no meio. Esta situação ocorre em virtude dos processos competitivos existentes entre os sítios ativos. Os experimentos de lavagem mostraram que o biossurfactante não foi capaz de melhorar a eficiência de remoção dos metais. Os resultados obtidos pelos tratamentos controle (somente água pura) tiveram valores muito semelhantes aos que continham biossurfactante. Quando a solução de lavagem continha o biossurfactante em altas concentrações, foi encontrada, em algumas amostras, queda na eficiência de remoção. Análises de cromatografia líquida permitiram concluir que o biossurfactante foi adsorvido às amostras de solo, sendo esta a consequência da não observação da eficácia do extrator na remoção dos metais. Cabe ressaltar, entretanto, que a surfactina obtida apresenta potencial de ligar-se aos metais, uma vez que os testes de adsorção desta aos metais foi confirmado pelos experimentos realizados. De acordo com os resultados encontrados, pode-se inferir que a surfactina tem maior potencial de remoção de metais em meio líquido do que em meio sólido, devido a menor possibilidade de adsorção na matriz sólida. Em solo, os resultados indicaram potencial de utilização deste biossurfactante como agente de estabilização dos metais em métodos de remediação in situ .

O município de Viamão está localizado na região metropolitana de Porto Alegre, no estado do Rio Grande Sul. A barragem Mãe d\'Água foi construída em 1962, com o intuito de atender à demanda da Universidade Federal do Rio Grande do Sul, mais precisamente o Instituto de Pesquisas Hidráulicas, porém, devido à falta de planejamento urbano, durante os últimos quarenta anos, vem acarretando uma diversificada série de passivos ambientais, como contaminantes orgânicos e/ou inorgânicos. Neste seguimento, o presente trabalho busca avaliar as concentrações dos metais Zinco e Níquel, teores de matéria orgânica e a composição granulométrica nas diferentes profundidades amostradas em testemunhos de sedimentos produzidos nesta bacia hidrográfica que compõe a barragem Mãe d\'Água. As coletas de amostras foram realizadas em junho de 2014, sendo amostrados quatro testemunhos sedimentares distribuídos no lago da referida barragem. Para a extração dos testemunhos foi utilizado um amostrador de núcleo \"Piston Core\". Os sedimentos da fração menor que 63μm foram destinados a análise química para verificação da presença e concentração dos elementos traço: Níquel (Ni) e Zinco (Zn). A metodologia de digestão ácida empregada é a EPA 3050, adotada pela U.S. Environment Protection Agency, sendo que as análises foram realizadas em duplicata e, para controle de qualidade, foram utilizados dois materiais de referência da USGS (U.S. Geological Survey): SGR-1b e SCO-1. Com os resultados obtidos, a caracterização granulométrica da sedimentação sob o barramento mostrou-se suscetível a contaminação por metais ao longo nas últimas décadas. Todas as amostras apresentaram concentrações de Zn e Ni acima do valor de background local e com padrões de crescimento, portanto, evidenciam a existência de enriquecimento dos sedimentos por estes elementos. Os teores de matéria orgânica quando correlacionados as concentrações de Zn e Ni evidenciaram o crescente enriquecimento nos testemunhos analisados, confirmando a alta afinidade destes elementos à sedimentos compostos de fração orgânica. O índice de geoacumulação para a maior parte das concentrações dos metais nas diferentes profundidades encontra-se caracterizadas como não poluída. Considerando que a área de estudo se caracteriza historicamente pela ocupação residencial, ações antropogênicas podem ser consideradas as principais provedoras dos passivos ambientais aos corpos d\'água. / The municipality of Viamão is located in the metropolitan region of Porto Alegre, state of Rio Grande do Sul. The Mãe D\'água Dam was built in 1962, so that demands from the Federal University of Rio Grande do Sul, more precisely the Institute of Hydraulic Research could be met. However, due to a lack of urban planning over the past forty years, the dam has caused several environmental liabilities, such as organic contaminants and / or inorganic contaminants. This manuscript addresses an evaluation of the concentrations of the metals zinc and nickel metals, organic matter content and particle size composition at different depths sampled in sediment cores produced in the watershed that comprises Mãe d\'Água. Four sediment core distributed in the dam lake were collected in June 2014, by \"Piston Core\" core sampler. Sediments whose fraction was lower than 63μm were subjected to chemical analyses regarding the presence and concentration of nickel (Ni) and zinc (Zn). The acid digestion methodology employed was EPA 3050, adopted by the US Environment Protection Agency. The analyses were performed in duplicate and two USGS (US Geological Survey) reference materials, namely: SGR-1b and SCO-1 were used for the quality control. The particle size characterization of sedimentation under the bus has proved susceptible to metal contamination over the past decades. All samples showed concentrations of Zn and Ni higher than the local background values and growth patterns, which evidenced an enrichment of sediments. In comparison to the organic matter content, the Zn and Ni concentrations showed a growing enrichment, which confirmed the high affinity of these elements for sediments composed of organic fraction. The geoaccumulation index for most of the metal concentrations at different depths has been characterized as non polluted. As whereas the study area is historically by historically residential occupation, anthropogenic actions can be considered the main causes of environmental damage to water bodies.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-05-29T16:17:04Z No. of bitstreams: 1 DISSERTAÇÃO MESTRADO - DAVID NEVES.pdf: 7961414 bytes, checksum: a6e16e2489660cbcfdc1ee3990007b0a (MD5) / Made available in DSpace on 2017-05-29T16:17:04Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO MESTRADO - DAVID NEVES.pdf: 7961414 bytes, checksum: a6e16e2489660cbcfdc1ee3990007b0a (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / As águas superficiais brasileiras vêm sofrendo constantes alterações em sua qualidade devido às atividades antrópicas e influências do uso e ocupação da região do entorno das bacias hidrográficas. Diante da complexidade dos sistemas lóticos, através de mét odos estatísticos , muitos pesquisadores buscam identificar variáveis representantes d as condições do corpo hídrico. Neste contexto, o objetivo do trabalho foi analisar temporal e espacialmente os aspectos hidrogeoquímico s e de qualidade das águas dos rios Piabanha, Paraibuna e Paraíba do Sul no município de Três Rios ( RJ ) , por meio de análise fatorial . Para isso foram selecionados oito pontos de amostragens ao longo dessas drenagens, sendo seis localizados no rio Paraíba do Sul, um no Piabanha e um no Parai buna. Além de medidas físico - químicas ―in situ‖ como pH, potencial oxi - redutor, condutividade elétrica e oxigênio dissolvido , a mostras foram coleta da s trimestralmente durante um ano hidrológico para análises de íons como Na + , K + , Mg 2+ , Ca 2+ , Cl - , SO 4 2 - , HCO 3 - , F - e B - , elementos traço Al, As, Ba, Cd, Cu, Cr, Fe, Hg, Mn, Mo, Ni, Se, Sr e V, nutrientes como N - total, NH 4 + , NO 2 - , NO 3 - , P - total e PO 4 3 - , SiO 2 , coliformes totais , termotolerantes, material particulado em suspensão - MPS , carbono orgânico dissolvido - COD e demanda bioquímica de oxigênio - DBO . Dentre os parâmetros físico - químicos, apenas o oxigênio dissolvido e a turbidez apresentaram discordância com os valores de referência estabelecido na Resolução CONAMA 357 de 2005. A concentração de MPS foi con dicionada ao regime pluviométrico da área de estudo, de modo que as maiores concentrações foram registradas no período chuvoso e as menores no período de estiagem. No entanto, as diversas barragens e/o u sistemas de contenções de erosões presente s a montant e dos segmentos amostrados , reduziram em maior ou menor grau os valores de MPS obtidos nos três rios. Para os períodos chuvoso e seco , as águas superficiais foram classificadas predominantemente como bicarbonatada sódica a mista. Entre as frações nitrogena das, o nitrato prevaleceu em época seca , como resultado da oxidação da matéria orgânica de efluentes domésticos. Dentre os metais, os elementos - traço Al, Fe e Hg foram os mais representativos para depreciação da qualidade hídrica. De modo geral, a qualidad e das águas superficiais durante o período chuvoso foi influenciada por processos erosivos, ao passo que no período seco foi controlada pel o escoamento de base e pelo lançamento de efluentes domésticos sem tratamento prévio / The Brazilian surface waters have been constantly changing th eir quality due to the anthropic activities and influences of the use and occupation of the region around the watersh eds. Given the complexity of the lotic systems, many researchers have sought through statistical methods to recognize variables that can represent the conditions of the hydric body. In this context, the aim of thi s work was to analyze in the time and in t he space the hydrogeochemical aspects and water quality of the Piabanha, Paraibuna and Paraíba do Sul rivers in Três Rios municipality, Rio de Janeiro State , and its surroundings by multivariate statistical analyzes. Therefore, eight sampling points were s elected along those wat er bodies, which six are situated in the Paraíba do Sul river, one in Piabanha and one in Paraibuna. The samples were collected quarterly during a hydrological year. In the field , the physicochemical parameters were measured in loco such as pH, oxy - reductive potential, electrical conductivity and dissolved oxygen and in the laboratory were carried out analyzes for the ions Na + , K + , Mg 2+ , Ca 2+ , Cl - , SO 4 2 - , HCO 3 - , F - and B - ; for the trace - elements Al, As, Ba, Cd, Cu, Cr, Fe, Hg, Mn, Mo, Ni, Se, Sr e V; for the main nutrients N - total, NH 4 + , NO 2 - , NO 3 - , P - total and PO 4 3 - , SiO 2 , the total coliforms and thermotolerants, the suspension particulate matter – SPM, the dissolved organic carbon – DOC and the biochemical oxygen demand – BOD. Among the physical - chemical parameters, only the dissolved oxygen and turbidity showed disagreement with the reference values s et out in Federal R esolution CONAMA 357/ 2005 . The concentration of SPM was conditioned by the rainfall behavior of the study area, disp laying the highest concentrations in the rainy season and the lowest ones in the dry season. However, the various dams and/or retaining walls present upstream from the segments sampled, reduced the SPM values obtained in the three rivers. The surface wate rs were chemically classified as sodium bicarbonate to mix for both wet and dry periods . Among the nitrogenous fractions present in surface waters , the nitrate prevailed in the dry season as a result of the oxidation of the organic matter from domestic eff luents. Regarding the trace elements Al e Hg were the most representative for the depreciation of water quality. In general, the quality of the surface waters during the rainy season was influenced by erosive processes in the rivers banks, while in the dry season the influence was based on the base flow and on the launch of domestic effluent without previous treatment

L’accroissement de l’urbanisation et le développement industriel modifient la composition des géosphères de la Terre, en augmentant le nombre de problèmes géoécologiques et en affectant négativement la santé humaine. Actuellement, plus d'attention est accordée à la surveillance de l'état des composants de l’environnement naturel urbain. En Russie, les méthodes biogéochimiques (par ex., l'application de feuilles des arbres comme un récepteur naturel de la pollution) sont largement utilisées pour caractériser les problèmes géoécologiques des territoires dans des conditions d’intensité d’activités industrielles. Dans les pays occidentaux, les méthodes permettant d'estimer l'impact des facteurs ambiants sur la géosphère et la santé humaine sont répandues, parmi lesquelles l'évaluation des impacts du cycle de vie (ÉICV). Cependant, ces méthodes ne sont toujours pas appliquées en combinaison. L’utilisation d’indicateurs efficaces reflétant l'intensité de l'impact anthropique sur les écosystèmes; d’une cartographie de la distribution des polluants, ainsi que l'utilisation a posteriori de ces résultats dans l'évaluation des impacts sur l'environnement et la prédiction de leurs effets négatifs des entreprises industrielles (toxicité humaine et l'écotoxicité) sont pertinents pour l'évaluation complète des écosystèmes urbains. Cette méthode intégrée a été proposée et mise en œuvre sur le territoire d’Ust-Kamenogorsk, l'une des villes ayant subie des transformations technogéniques significatives au Kazakhstan avec un ensemble spécifique d’entreprises / With widespread urbanization and industrial development, the composition of the Earth's geosphere shells has changed, increasing the number of geoecological problems of territories and negatively affecting human health. Currently, more attention is being paid to monitoring the state of the components of urban natural environments. In Russia, biogeochemical methods (e.g. applying tree leaves as a kind of natural receptor of pollution) are widely used to characterize the geoecological problems of the territories under the pressure of intensive industrial activities. In Western countries, methods allowing us to estimate the impact of ambient factors on ecosystems and human health have become widespread; life cycle impact assessment is among them. However, these methods still have not been applied in combination. Therefore, the implementation of a comprehensive assessment of urban ecosystems using indicators reflecting the intensity of anthropogenic impact on ecosystems, following mapping of pollutant distributions, as well as the subsequent use of the results in the evaluation of the industrial enterprises' impact on the environment and in the prediction of the negative effects of pollution (human toxicity and ecotoxicity) are relevant. Such integrated method combining two methodologies was suggested and implemented in the territory of Ust-Kamenogorsk city, one of the significantly technogenic transformed cities in Kazakhstan with a specific set of enterprises

Les récifs coralliens de Nouvelle-Calédonie constituent un « hot-spot » de biodiversité marine et sont classés au patrimoine mondial de l’Unesco depuis 2008. Ces récifs sont dans un bon état général, mais ils sont soumis à des pressions anthropiques de plus en plus intenses, engendrées par un développement industriel (mines de nickel) et urbain croissant.Mieux comprendre le fonctionnement des écosystèmes lagonaires calédoniens est donc devenu un enjeu majeur. Ce travail s’inscrit dans cette démarche, avec pour objectifs principaux : (1) de reconstruire l’architecture des réseaux trophiques de ces écosystèmes (méthode des isotopes stables), (2) de déterminer leurs niveaux de contamination en éléments traces métalliques et en polluants organiques, et (3) de décrire l’intégration et le cheminement de certains de ces contaminants en leur sein. L’étude des écosystèmes récifo-lagonaires et de leurs réseaux trophiques a été réalisée au travers du prisme de prédateurs méconnus de hauts rangs trophiques : les poissons anguilliformes (murènes, congres et poissons-serpents). Pour ce faire, différentes sources de matière organique (MO) et divers consommateurs, parmi lesquels les poissons anguilliformes, ont été prélevés dans plusieurs sites répartis sur un gradient côte-large et provenant de deux zones du lagon sud.Quatre réseaux trophiques ont été identifiés au cours de ce travail. La voie benthique basée sur la MO du turf algal est la voie trophique majeure, commune à tous les poissons anguilliformes. L’utilisation complémentaire de la voie benthique sédimentaire et de la voie « pélagique lagonaire », est également mise en évidence avec une importance variable selon les espèces. En revanche, la MO provenant des phanérogames marines n’est intégrée qu’indirectement, par le biais de la voie détritique. Les différentes espèces d’anguilliformes appartiennent donc à des réseaux trophiques en partie divergents selon leur habitat (substrat dur ou meuble) et leur régime alimentaire (micro-, macrocarnivore ou piscivore). Ces prédateurs de hauts niveaux trophiques, consommant principalement des crustacés et des poissons mais également occasionnellement des annélides polychètes et des céphalopodes, se révèlent pour la plupart opportunistes. Une compétition entre certaines espèces est soulignée par le recouvrement de leurs niches trophiques. Les sources de MO et les consommateurs récifaux du lagon calédonien accumulent des concentrations modérées à fortes en éléments traces d’origine agricole, urbaine et minière. La bioaccumulation dépend des propriétés physico-chimiques du contaminant lui-même et des caractéristiques propres à l’organisme (taille, habitat, régime alimentaire, etc.). Ainsi, les contaminants sont répartis différemment entre les compartiments, et seuls Hg et As sont bioamplifiés le long des réseaux trophiques. Une contamination du lagon par les polluants organiques est également soulignée. Bien que les concentrations mesurées chez les poissons anguilliformes restent relativement faibles, l’étendue spatiale de cette contamination, ainsi que la détection de pesticides très toxiques dont l’utilisation est interdite (DDT), attestent de la nécessité à considérer cette pollution avec attention. Toutes ces considérations renforcent l’importance de mener un suivi à long terme des contaminations d’origines diverses en relation avec le fonctionnement trophique des systèmes récifo-lagonaires. / New Caledonian coral reefs constitute a « hot spot » of marine biodiversity and were registered World Heritage by UNESCO in 2008. These reefs are in good health, but they are subject to intense anthropic threats, induced by the increase of industrial (nickel mining) and urban development. A better understanding of the functioning of the Caledonian coral reefs has become a major issue. This work is part of this approach, with as main goals to: (1) reconstruct the architecture of food webs of these ecosystems (stable isotope method), (2) determine their contamination levels in metallic and organic contaminants and (3) describe integration and pathways of some of these contaminants through the food webs. The description of ecosystems and their food webs was carried out by the study of unknown predators: the anguilliform fish (moray, conger and snake eels). Different sources of organic matter (OM) and consumers, including anguilliform fish, were sampled in several sites distributed over a coast to barrier reef gradient within two areas of the south lagoon. Four food webs were identified. The benthic pathway based on the algal turf OM is the main food web, common to all anguilliform fish. The complementary use of benthic sedimentary (SOM) and “lagoon pelagic” (POM) food webs, is also highlighted with variable importance according to species. In addition, OM from seagrasses is included indirectly by the detrital pathway. The numerous anguilliform fish species belong to diverse food webs in part, depending on their habitat (hard and/or soft bottom) and their diet (micro/macro carnivores or piscivores). These predators of high trophic level, consuming mainly crustaceans and fish but also more occasionally annelids and cephalopods, are mostly opportunistic. A competition between some species is underlined by the overlap of their trophic niches. Sources of OM and consumers of the Caledonian coral reefs accumulate moderate to strong concentrations of trace elements issued from agricultural, urban and mining origins. Bioaccumulation depends on both physical and chemical properties of the contaminant and the organism’s own characteristics (size, habitat, diet, etc.). So, contaminants are distributed differently between compartments and only Hg and As are biomagnified along food webs. Contamination of the lagoon by organic pollutants is also pointed out. Even if concentrations measured in anguilliform fish are rather low, widespread contamination, plus the detection of toxic and forbidden pesticides (DDT), confirm the necessity to include this pollution in further studies. All these considerations reinforce the importance of setting up a long-term tracking system of contamination from diverse origins, linked with the trophic functioning of food webs.

Face à la toxicité des éléments traces métalliques (ET) dans l’environnement, les plantes ont développé différentes stratégies aujourd’hui exploitées en phytoremédiation. Les arbres paraissent plus efficaces que les herbacées pour la phytoextraction de par leur importante biomasse et leur système racinaire plus profond. Ces travaux ont donc été menés sur des espèces ligneuses largement répandues dans la région Limousin, plus particulièrement des conifères: le Douglas, le mélèze hybride et ses deux parents, le mélèze d’Europe et le mélèze du Japon. Plusieurs modèles de culture ont été utilisés pour permettre, par des approches complémentaires, une meilleure appréhension des réponses de ces conifères aux ET : des plantules cultivées in vitro et des germinations ou des arbres âgés de 2 ans cultivés sous serre. Les conifères ont été exposés soit à un seul ET, le Cadmium (Cd), soit à plusieurs ET (As, Pb, Sb) présents dans des sols collectés sur deux anciens sites miniers. Les résultats ont montré que, parmi les espèces étudiées, le Douglas présentait le taux d’accumulation le plus élevé en Cd. Cependant, la quantité stockée dans la biomasse aérienne est restée faible par rapport à d’autres espèces d’arbres déjà utilisées en phytoextraction. Par ailleurs, la caractérisation chimique des pectines de la paroi a mis en évidence des modifications quantitatives et qualitatives suggérant un processus d’exclusion du Cd. Au niveau intracellulaire, les résultats ont montré que les polyamines et les oligopeptides riches en thiols ne semblaient pas impliqués dans la compartimentation du Cd. En revanche, une accumulation de proline a été observée en réponse au Cd et à d’autres ET, suggérant une implication de la proline comme molécule antioxydante et / ou chélatrice d’ET. L’ensemble des résultats a mis en évidence la nécessité d’optimiser la croissance des conifères et la phytodisponibilité des ET du sol avant de pouvoir proposer ces conifères, et notamment le Douglas, pour la phytoextraction d’ET. / Given the toxicity of trace elements (TE) in the environment, plants developed varions strategies used currently for phytoremediation. Trees appear more efficient than herbaceous species for phytoextraction as they have a larger biomass and a deeper root system. The work was thus performed on woody species widespread in Limousin region, particularly conifers: Douglas fir, hybrid larch and its two parents, European larch and Japanese larch. Several culture models were used to allow, through complementary approaches, a better understanding of the response of these conifers to TE: in vitro grown plantlets and seedlings or 2-year-old trees grown in greenhouse. Conifers were exposed to a single TE, cadmium (Cd), or to several TE (As, Pb, Sb) present in soils collected from two former mining sites. Among investigated species, results showed that Douglas exhibited the highest rate of Cd accumulation. However, the amount stored in aboveground biomass remained low compared to other tree species already used in phytoextraction. Furthermore, the chemical characterization of cell wall pectins highlighted quantitative and qualitative modifications suggesting a Cd exclusion process. At the intracellular level, results showed that polyamines and thiol-rich oligopeptides did not appear to be involved in Cd compartmentation. However, a proline accumulation was observed in response to Cd and other TE, suggesting an involvement of proline as antioxidant molecule and / or TE scavenger. Overall, results highlighted the need to optimize conifer growth and soil TE phytoavailability before to propose these conifers, particularly Douglas, for the phytoextraction of TE.

Contexte et objectifs : Au Bénin, le « secteur informel » représente près de 80 % des travailleurs avec une prédominance d’acteurs dans l’artisanat, suivi par le secteur privé moderne (11 %) et la fonction publique (9 %). La situation socio-professionnelle des artisans est caractérisée par l’absence d’équipements de protection, par l’exposition à des nuisances physiques et chimiques et par l’absence de sécurité sociale. L’objectif principal de ce travail de thèse était d’étudier l’impact des conditions de travail sur la santé des forgerons-ferblantiers exerçant dans le cadre de l’économie informelle, à Cotonou au Bénin. Ce travail a permis également d’évaluer l’imprégnation sanguine en éléments traces métalliques chez les ferblantiers par comparaison avec les concentrations observées dans la population masculine de Cotonou, non exposée professionnellement. Cette partie de l’étude a nécessité la mise en place d’une première enquête en population générale, chez 70 donneurs de sang à Cotonou afin de proposer des valeurs de référence pour 29 éléments traces métalliques.Méthode : Une étude transversale a été réalisée à Midombô sur le site des artisans ferblantiers dans le 3ème arrondissement de Cotonou au Bénin. Au total, 84 responsables d’atelier sur 102 ont donné leur accord de participation pour l’étude des postes et conditions de travail, soit un taux de participation de 82,4 %. Parmi les 251 personnes travaillant dans les 102 ateliers investigués, 135 ferblantiers ont accepté de venir au centre de santé Erasme (53,8 %) pour bénéficier d’un entretien médical gratuit. Dans cette population, 31 personnes étaient des apprentis (23,0 %) et 104 étaient des artisans ou maitres-artisans (77,0 %). Résultats : Il a été observé des niveaux de bruit supérieurs à 85 décibels dans 58,3 % des ateliers, avec une durée du travail en moyenne de 10 h par jour pouvant être à l’origine des déficits auditifs (légers à sévères) observés dans 99,3% des cas. L’exposition directe aux fumées et poussières métalliques (38,52 %) et la consommation d’aliments au poste de travail seraient à l’origine d’une imprégnation métallique. Pour 6 éléments traces, plus de 20 % des ferblantiers présentaient des concentrations sanguines supérieures aux valeurs de référence de la population générale. Par ordre croissant de niveau d’imprégnation, il s’agissait du molybdène, du cuivre, du strontium, de l’étain, de l’antimoine, et du plomb. Environ 71 % des ferblantiers présentaient des plombémies supérieures au 95ème percentile des concentrations retrouvées en population non exposée à Cotonou. Pour les moins de 18 ans, la prévalence des travailleurs ayant une plombémie ≥ 100 μg/L était de 83 %. Une baisse de l’acuité visuelle non corrigée (> 20 %) et une hypertension artérielle non traitée (27,4 %) ont été dépistées chez les ferblantiers participants. Conclusion : Les travailleurs informels sont dans une situation de grande vulnérabilité du fait d’une faible couverture en matière de protection sociale et d’un niveau élevé d’exposition aux risques professionnels. Compte tenu du grand nombre de travailleurs dans l’économie informelle, l’amélioration de la santé et de la sécurité au travail des acteurs de ce secteur, devrait permettre un renforcement du capital humain et la réduction des maladies professionnelles encore mal documentées. / Context and objectives: In Benin, the "informal sector" represents almost 80% of workers with a predominance of craftsmen, followed by the modern private sector (11%) and the civil service (9%). The socio-professional situation of craftsmen is characterized by the lack of personal or collective protective equipment, exposure to physical and harmful chemical substances and a lack of social security. The main objective of this thesis was to study the impact of working conditions on the health of tinsmiths in the informal economy in Cotonou, Benin. This research also allowed us to evaluate the blood impregnation of trace elements in tinsmiths compared to the background levels of the non-occupationally exposed male population of Cotonou. This part of the study required a first survey of 70 blood donors in Cotonou, in order to propose reference values for 29 trace elements. Method: A cross-sectional study was carried out in Midombô on the site of the tinsmiths in the 3rd district of Cotonou in Benin. Study population: A total of 84 workshop managers out of 102 gave their agreement to participate in the study of work places and conditions (participation rate of 82.4 %). Among the 251 tinsmiths working in the 102 workshops investigated, 135 agreed to go to the “Erasmus” health center (53.8%) for free medical care. In this population, there were 31 apprentices (23.0 %) and 104 craftsmen or master craftsmen (77.0 %). Results: Noise levels greater than 85 decibels were observed in 58.3% of the workshops, with an average working time of 10 hours per day. This exposure can be the cause of hearing impairment (mild to severe) observed in 99, 3% of the cases. Direct exposure to metal fumes and dust (38.52 %) and the consumption of food at the workplace are the cause of metallic impregnation. For 6 trace elements, more than 20 % of the tinsmiths had blood concentrations above the reference values of the general population. These elements, classified from the lowest to the highest level of impregnation were molybdenum, copper, strontium, tin, antimony, and lead, respectively. Approximately 71% of the tinsmiths had lead levels above the 95th percentile of concentrations found in unexposed populations in Cotonou. 83% of the workers who were under 18 years of age had blood lead levels ≥ 100 μg / L. Uncorrected visual acuity (> 20%) and untreated arterial hypertension (27.4 %) were detected in the participating tinsmiths. Conclusion: Informal workers are in a very vulnerable situation due to poor social protection and a high level of exposure to occupational risks. Given the large number of employees in the informal sector, improving the occupational health and safety of these workers should help to strengthen human capital and reduce the incidence of occupational diseases that are still poorly documented.