A ocorrência de inundações e alagamentos em Porto Alegre é objeto de estudo de diversas pesquisas, as condições climáticas e o relevo do município propiciam que esses fenômenos sejam recorrentes. Esta pesquisa objetiva analisar as intervenções realizadas pelo uso e ocupação da terra na morfologia original e na dinâmica geomorfológica no entorno de vias do município de Porto Alegre onde é identificada a concentração dos eventos de inundação e/ou alagamento que causam interferências no trânsito. Como contextualização histórica foram realizadas a análise da expansão urbana do município de Porto Alegre e a verificação da ocorrência de inundações e/ou alagamentos no município. A partir da análise dos dados climáticos foram selecionadas datas nas quais houve um total pluviométrico acima de 30 mm. Com isso foram identificadas as áreas de concentração dos eventos que causaram alteração no trânsito, a saber: a bacia hidrográfica do arroio Almirante Tamandaré e a bacia hidrográfica do arroio Cavalhada (a com maior número de ocorrências na zona sul de Porto Alegre). A partir da seleção dessas áreas mapeou-se a morfologia original, caracterizando a morfodinâmica anterior às intervenções antrópicas. A morfologia original dessas áreas, quando analisada em conjunto com dados históricos, remete à condição potencial aos alagamentos e/ou inundações. Posteriormente foram mapeados o uso e ocupação da terra atual das áreas de estudo, destacando a densidade de ocupação dos lotes, assim pode-se analisar a relação entre as intervenções na dinâmica geomorfológica originalmente existente e a concentração de alagamentos nessas áreas. As intervenções realizadas pelo processo de ocupação desses espaços acarretaram mudanças na morfologia original que interferiram na dinâmica superficial, especialmente no que se refere ao escoamento das águas pluviais, podendo gerar ou potencializar os eventos de alagamento e inundações na área de estudo. / The occurrence of floods and inundation in Porto Alegre is the object of study of several research efforts. These are recurrent events determined by the climatic conditions and topography of the city. The present research aims at analyzing the interventions made by the use and occupation of the land and its effects on the original morphology and geomorphology around the city of Porto Alegre, where the concentration of floods and / or inundation are identified and the impacts on urban traffic evaluated. As a historical perspective, the analysis is made of the urban expansion of the city of Porto Alegre, that focus on the descrition of flooding and / or inundation occurences in the city. From the analysis of climate database, specifc dates were selected in which the rainfall was higher than 30 mm. The areas of concentration of events that caused changes in traffic, were identified namely: the Admiral Tamandaré hydrographic system and the Cavalhada stream (with the highest number of events in the southern area of Porto Alegre). From the selection of these areas, the original morphology was mapped allowing the characterization of morphodynamic features previous to human interventions. The original morphology of these areas, were analyzed in conjunction with the historical database, which enabled the potential for flooding and / or inundation to be identified. Subsequently the use and occupation of the current areas of study were mapped, highlighting the density of occupation, in a way of assessing the relationship between interventions in the original geomorphological dynamics and concentration of flooding in these areas. The interventions by the process of occupation in these areas led to changes in the original morphology that interfered in the dynamic surface, especially in regard to stormwater runoff. This may generate or enhance the event of flooding and inundation in the area of study.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The mode of production used as raw material for (re) production of natural resources, as different as possible. It is, therefore justified the removal of vegetation, for real estate, agropastoral and mining, causing serious damage to the environment and the contamination of river channels through the dumping of sewage in natura. The coastal town Estância/Sergipe no exception to this reality, where production and occupancy of their spaces not meeting the timely rebalancing of environmental systems is maintaining environmental sustainability. The city is located east of the state of Sergipe, with a territory of 647.62 km² and is part of the south coast. With a proposal for a geoenvironmental analysis of the municipality aimed to identify the natural physical environments and anthropogenic lead currently processed in resort and its possible consequences to the local environment. The analysis method was based on geo approach, suitable for integrated analysis of various environmental units contained in the municipality and the methodological procedures were based on geospatial technologies, preparation of thematic maps, field work, reading relevant documents to the investigation as bibliographies consistent with the research object and the applied theory, knowledge of the socioeconomic and environmental processes in the city to present, from the integrated analysis, to identify the environmental damage in the landscape units from human activity. The municipality of Estância space is a very dynamic nature, consisting of fragile ecosystems to man's actions. Patches of Atlantic Forest and mangrove ecosystem is periodically cleared, burned and filled to make way for housing and economic activities. The waters of the river channels that bathe the city are polluted mainly by domestic sewage and fecal coliform. Thus, it becomes necessary to develop research projects that assist in the formulation of public policies, planning, use and preservation of natural spaces, since the balance of the physical environment is fundamental to the welfare and maintenance of man on the surface of planet Earth. / O modo de produção utiliza como matéria-prima para sua (re)produção os recursos naturais, os mais diversos possíveis. Assim, é justificada a retirada da cobertura vegetal, para fins imobiliários, agropastoris e de extração mineral, causando sérios danos ao meio ambiente, bem como a contaminação dos canais fluviais através do despejo do esgoto doméstico in natura. O município costeiro de Estância/Sergipe não foge a esta realidade, onde a produção e ocupação dos seus espaços não respeitam o tempo hábil dos sistemas ambientais reequilibrarem-se, mantendo a sustentabilidade ambiental. O município localiza-se a leste do estado de Sergipe, com um território de 647,62km² e faz parte do litoral sul do estado. Com uma proposta de análise geoambiental do município, objetivou-se identificar os ambientes físicos naturais e as derivações antrópicas processadas atualmente em Estância e suas possíveis consequências ao meio ambiente local. O método de análise baseou-se na abordagem geossistêmica, apropriada para análises integradas das diversas unidades ambientais contidas no município e os procedimentos metodológicos basearam-se em técnicas de geoprocessamento, elaboração de cartas temáticas, trabalhos de campo, leituras de documentos pertinentes à investigação como bibliografias condizentes com o objeto de pesquisa e com a teoria aplicada, conhecimento dos processos socioeconômicos e ambientais presentes no município para, a partir da análise integrada, identificar os danos ambientais, nas unidades de paisagem, provenientes da ação antrópica. O território do município de Estância é um espaço físico natural muito dinâmico, constituído por ecossistemas frágeis às ações do homem. Manchas de Mata Atlântica e o ecossistema manguezal são periodicamente desmatados, queimados e aterrados para dar lugar a moradias e as atividades econômicas. As águas dos canais fluviais que banham o município estão contaminadas, principalmente por esgotos domésticos e coliformes fecais. Assim, torna-se necessário o desenvolvimento de projetos de pesquisa que auxiliem na formulação de políticas públicas, no ordenamento, no uso e na preservação dos espaços naturais, uma vez que o equilíbrio do meio físico é fundamental para o bem estar e manutenção do homem na superfície do planeta Terra.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-25T16:57:10Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) dissertação Cláudio Oceanografia.pdf: 1598552 bytes, checksum: 2f98d7d6edbf021730ab15fbc7a05dcd (MD5) / Made available in DSpace on 2017-05-25T16:57:10Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) dissertação Cláudio Oceanografia.pdf: 1598552 bytes, checksum: 2f98d7d6edbf021730ab15fbc7a05dcd (MD5) Previous issue date: 2014-03-28 / Os ambientes costeiros estão entre os mais ameaçados do mundo. O turismo corresponde a um dos principais processos antrópicos, geralmente feito de forma desordenada, degradando os recifes. Porto de Galinhas (aprox 70 km de recife) é um dos maiores pólos turísticos do Brasil recebendo cerca de 400 mil visitantes na alta estação (novembro a fevereiro). Por falta de uma fiscalização eficiente, impactos como pisoteio e atracamentos das jangadas nos corais estão destruindo a área, modificando a comunidade do local. Para avaliar a qualidade do ambiente, além de parâmetros físicos, são necessários indicadores biológicos, sendo os peixes os mais utilizados. O objetivo do trabalho foi verificar possíveis mudanças na comunidade que vive no topo e crista recifal, determinando quais espécies seriam consideradas bioindicadores. A chamada “piscina dos oito” foi selecionada como área de estudo, que foi separada em duas áreas: tratamento e controle. Os pontos selecionados possuem características geomorfológicas semelhantes, diferenciando-se pela ocupação (tratamento) ou não (controle) das Jangadas. Um total de 48 censos, no período de jul/12 a jun/13 (24 no domingo e 24 na segunda) foram realizados. No estudo, foram contabilizados 3.508 indivíduos, pertencentes a 31 espécies de 16 famílias de peixes nas duas áreas amostradas nos recifes de Porto de Galinhas. Na área tratamento foram vistas 21 espécies, número menor quando comparado com a área controle no qual que foram identificados 28. As famílias mais representativas foram Labridae (8 espécies), seguida por Pomacentridae (4 espécies). Pomacentridae, marcadamente representada por Stegastes fuscus (n= 2.344), representando 66% do total identificado. Foi verificada diferença na diversidade de espécies entre as áreas tratamento e controle. Este resultado mostrou-se significativo (p=0,001), no qual a área controle apresenta uma maior diversidade de espécies. Os dados coletados indicam uma mudança na estrutura da comunidade situada na crista recifal em Porto de Galinhas. Algumas espécies aproveitam-se do impacto decorrente das jangadas, que remove a cobertura algal e os organismos que ali vivem, facilitando a disponibilidade de alimento. Outras espécies reagem diferentemente a estes impactos abrigando-se embaixo das jangadas, provavelmente em busca de sobra e/ou proteção, enquanto outras fogem e somente são encontradas na área controle. Pode-se concluir que os impactos antropogênicos decorrentes do uso excessivo de jangadas estão modificando a diversidade, abundancia e comportamento na comunidade de peixes na “piscina dos oito” de Porto de Galinhas. / Coastal environments are among the most threatened in the world. Tourism represents one of the main anthropogenic processes, usually done in a disorderly manner, with that, degrading reefs. Porto de Galinhas (approx. 70km reef ) is one of the biggest tourist centers in Brazil with about 400 thousand visitors in the high season (November to February). For lack of effective monitoring, the impact of rafts such as trampling and docking are destroying reefs in the area, modifying the local community. To evaluate the quality of the environment, and physical parameters, biological indicators are needed, the fish is the most used. The objective was to determine possible changes in the community that lives at the top and reef’s crest, determining which species would be considered bio-indicators. The so-called "Piscina dos oito" was selected as study field, which was separated into two areas: treatment and control. The selected points have similar geo-morphological characteristics, differentiating them by occupation (treatment ) or not (control ) of the rafts . 3,508 individuals belonging to 31 species of 16 families of fish sampled in two areas on the reefs of Porto de Galinhas were identified. In the treatment area 21 species were seen, a lower number compared with the control area in which they have been identified 28. The most representative families were Labridae (8 species), followed by Pomacentridae (4 species). Pomacentridae, highly represented by Stegastes fuscus (n=2,344), representing 66 % of the total identified. Difference in species diversity between the treatment and control areas was observed during the research months (july/12 to june/13) for both Sunday and Monday. This result was significant (p=0.001), in which the control area has a greater diversity of species. The data collected indicate a change in the structure of the reef’s crest community located in Porto de Galinhas. Some species take advantage of the arising impact of the rafts, which removes the alga cover and the organisms that live there, making it easier for food. Other species react differently to these impacts sheltering beneath the rafts, probably in search of leftovers and/or protection, while others flee and are only found in the control area. It can be concluded that anthropogenic impacts resulting from excessive use of rafts are changing the diversity, abundance and behavior in fish community "Piscina dos Oito" Porto de Galinhas.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Irrigation is an essential input that has enhanced, substantially, food production and has improved economic development in arid regions. Irrigation, also, has generated negative impacts to the environment and to human health. The aim of this work was to quantify and qualify the irrigation impacts and of the climatic seasonality over soil and water resource in Irrigated District of Baixo AcaraÃ, CearÃ, Brazil. Ten points spread out over the studied area were selected as monitoring stations. Two of them were sited in irrigated fields. Samples were collected monthly from Dezember/2003 to November/2005, November/2006, March and May/2007. The samples were analyzed for: pH, electrical conductivity (EC), Ca2+, Mg2+, Na+, K+, HCO3 -, PO4 -2, Cl-, NH4 +, NO3 -, SO4 -2 and Sodium Adsorption Ratio (SAR). Soil samples were collected in two different types of land use: irrigated field and uncultivated area field. Soils samples were taken for each 50 cm until water table (7 m) was reached, during wet and irrigation seasons. Multivariate statistical method, cluster analysis, was applied to classify the shallow wells inte similar groups in relation to water quality. To identify spacial variability of Na+, Cl-, CE, PO4 -2 e NO3 - in the water table it was used a GIS platform and the software: Global Mapper 5.0, ArcGis 9.1. The geostatistic process was performed using the Surfer 7.0. According to the results the highest values of changeable bases (Ca2+, Mg2+, Na+ e K+), Cl-, SAR AND NO3 - were presented in the water of P1 (sample station 1). These values were over the acceptable limit of Class 1 defined by CONAMA (Resolution 357/05). The analyzed variables showed a high spacial variability and a low temporal variability. The used soil management in the irrigated field, where shallow wells (P3 and P4) were sited, is not contributing to the contamination or water table by salts, yet. Also, the results show have that irrigation caused the groundwater concentration of NO3âN to increase from 1.52 to 19.3 mg L-1, thereby, exceeding the standards of the World Health Organization (WHO). / A irrigaÃÃo se constitui em um importante fator que contribui para a seguranÃa alimentar e possibilita o desenvolvimento econÃmico de muitas regiÃes, principalmente Ãridas e semi-Ãridas. Entretanto, se nÃo manejar adequadamente poderà vir a acarretar danos irreversÃveis ao meio ambiente com potenciais riscos à saÃde humana. Este trabalho teve por objetivo quantificar e qualificar o efeito da irrigaÃÃo e da sazonalidade climÃtica nos recursos solo e Ãgua do Distrito Irrigado do Baixo Acaraà â DIBAU, CearÃ. Foram selecionados 10 poÃos rasos como estaÃÃes de coletas de Ãgua, dos quais 2 (dois) estÃo inseridos no perÃmetro de irrigaÃÃo. As coletas de Ãgua foram realizadas mensalmente de dezembro de 2003 a novembro de 2005, novembro de 2006, marÃo e maio de 2007. As anÃlises quÃmicas foram realizadas no LaboratÃrio de Solo e Ãgua da EMBRAPA AgroindÃstria Tropical. Foram analisados: pH, CEa, Ca2+, Mg2+, Na+, K+, HCO3 -, PPO4 -, Cl -, NH4 +, NO3 -, SO4 -2 e RAS. As coletas de solo foram efetuadas em 2 pontos amostrais inseridos nas imediaÃÃes de dois dos 10 poÃos estudados, ambas coletadas no perÃodo seco e chuvoso, a cada 50 cm de profundidade da superfÃcie atà a zona de saturaÃÃo do lenÃol freÃtico. Para se classificar os poÃos em grupos de categorias semelhantes quanto à qualidade da Ãgua empregou-se a tÃcnica de estatÃstica multivariada, analise de agrupamento, empregando-se o pacote estatÃstico SPSS 13.0. Empregou-se tambÃm a plataforma SIG e os softwares: Global Mapper 5.0, ArcGis 9.1 e o Surfer 7.0 no processamento da geoestatÃstica para determinaÃÃo da variabilidade espacial do Na+, Cl-, CE, P-PO4 - e NO3 - na Ãgua do lenÃol freÃtico; como tambÃm para determinaÃÃo da direÃÃo da linha de fluxo do lenÃol freÃtico. Pelos resultados obtidos,verifica-se que as Ãguas do P1(Alparcatas) destacam-se por apresentar os valores mais elevados das bases trocÃveis (Ca2+, Mg2+, Na+ e K+), Cl-, RAS e NO3-, concentraÃÃes sempre acima dos limites mÃximos aceitÃveis para Classe 1 da ResoluÃÃo 357/05 do CONAMA. Ocorreu uma grande variabilidade espacial entre os poÃos estudados para as variÃveis analisadas, ademais nÃo se observou variabilidade temporal. O manejo praticado nos solos onde estÃo inseridos os poÃos P4 e P5, perÃmetro irrigado, por ainda nÃo estarem contribuindo com a contaminaÃÃo de sais na Ãgua do lenÃol freÃtico do DIBAU. Jà se percebe um aumento preocupante dos teores de nitrato nas Ãguas dos poÃos influenciados pela agricultura irrigada (P4 e P5), excedendo significativamente aos limites mÃximos aceitÃveis pela ResoluÃÃo 357/05 e pela Portaria 518/2004 para consumo humano.

Estudos tem salientado que a expansão urbana, fragmentação do habitat, desmatamento e sobreposição das áreas de vida das populações humanas e silvestres tem constribuido para o surgimento de doenças emergentes e reemergentes nas últimas décadas. A paisagem da floresta amazônica vem sofrendo constantemente a dominância antropica e como resultado suas populações silvestres encontram-se cada vez mais expostas ao contato com populações humanas e domesticas com um alto risco de transmissão de agentes infecciosos. A cidade de Manaus, localizada na Amazônia Brasileira, tem afrontado um crescimento desordenado e vertiginoso devido ao seu desenvolvimento industrial causando uma alteração constante em sua paisagem; representando um modelo potencialmente útil para entender os mecanismos de transmissão de doenças. Os primatas são as espécies evolutivamente mais próximas dos humanos e essa proximidade filogenética tem facilitado o compartilhamento de diversos agentes infecciosos. O presente estudo propõe utilizar subpopulações de sauim-de-coleira (Saguinus bicolor) que ocupam os fragmentos urbanos de Manaus como espécie sentinela, para avaliar a presença de agentes infecciosos na interface-humano primata. A pesquisa objetiva também determinar se a perturbação antrópica dos locais de estudo estaria favorecendo a transmissão desses agentes. Entre os anos 2011 e 2014 um total de 55 sauins de coleira foram capturados em 9 fragmentos florestais urbanos e 1 area controle. Análises moleculares foram realizados para detectar Rotavirus A, Hantavirus, Coronavirus, Flavivirus, Enterovirus, Influenza A, Adenovirus, Metapneumovirus, Virus Sincitial Respiratório Humano, Parainfluenza 1, 2, 3, 4, Virus do Oeste de Nilo e Plasmodium spp. Os resultados indicaram uma prevalência para Hantavírus de (4/48), Rotavírus (9/48). Pela primeira vez é detectada a presença de hantavírus em primatas neotropicais. Nossos dados indicaram que a presença de infeção estaria associada com a existência de algum tipo de impacto antrópico nos locais pesquisados. Nenhum indivíduo resultou infectado na area controle. / In past decades, numerous studies have highlighted how urban expansion, habitat fragmentation, deforestation, and superposition of human and wildlife population areas contribute to surges in emergent and reemergent diseases. As a result of continuing anthropogenic disturbance in the Amazon, wildlife populations find themselves increasingly exposed to human populations and their domestic animals, bringing higher risks of transmission of a variety of infectious agents. Manaus, located in the Brazilian Amazon, represents a potentially useful model to understand the mechanisms of disease transmission. The city has undergone a disorganized and precipitous growth with ongoing industrial development, causing constant landscape alteration. Because non-human primates are closely evolutionary related to humans they share a diversity of infectious agents. The present study proposes to use subpopulations of Pied tamarins (Saguinus bicolor) occupying urban forest fragments in Manaus as a flagship species to evaluate the presence of infectious agents at the human-nonhuman primate interface. It will also assess whether anthropogenic perturbation at sites favors transmission of agents within this human dominated matrix. During the period of 2011-2014 a total of 55 pied tamarins in 9 urban forest fragments and 1 control area. Molecular analyses were performed for the detection of Rotavirus, Hantavirus, Coronavirus, Flavivirus, Enterovirus, Influenza A, Adenovirus, Metapneumovirus, Sincytial Human Respiratory virus, Parainfluenza 1, 2, 3, 4, West Nile Virus and Plasmodium spp. The results indicate prevalence for Hantavirus (n =4/48) and Rotavirus (n =9/48). This is the first record of Hantavirus in neotropical primates. Data indicate that the presence of infection in the study sites could be associated with anthropogenic impact. The control area resulted uninfected.

Com base nos procedimentos metodológicos da Geomorfologia Antropogênica (RODRIGUES 1997a, 1997b, 2004, 2005 e 2010) e na abordagem da Geomorfologia Urbana Histórica, esse trabalho objetiva avaliar as correlações entre as intervenções urbanas nos sistemas hidromorfológicos e as tendências espaciais e frequência das inundações na bacia hidrográfica do Córrego da Mooca. Para essa avaliação foram gerados o mapa da morfologia original na escala de 1:25.000, para o reconhecimento das tendências originais dos processos hidromorfológicos, e os mapas do uso do solo de diversos anos (1952, 1962, 1972, 1994 e 2008), para investigar a história cumulativa das intervenções urbanas e obter dados de indicadores morfológicos e de materiais superficiais para a avaliação dos impactos da urbanização (RODRIGUES, 2010). Foram também identificados os eventos de inundação que ocorreram na bacia do Córrego da Mooca entre os anos de 1971 e 2011, com base nos reportagens dos jornais Gazeta da Vila Prudente e Folha de Vila Prudente. Os 85 eventos de inundação identificados no levantamento histórico foram mapeados e suas informações sistematizadas no quadro de geoindicadores de mudanças. Com base nessa sistematização foram selecionados indicadores para a avaliação das variáveis antrópicas e naturais na ocorrência das inundações. Os resultados obtidos permitiram avaliar que as inundações ocorrem em setores da antiga planície de inundação onde as tendências da morfologia original foram potencializadas pela morfologia antropogênica. Identificou-se também que os eventos de inundação relatados ao longo de 40 anos foram mais frequentes nas faixas de precipitação com o total diário de até 60 mm, sendo que 82,5% ocorreram na faixa entre 0,1 e 15 mm. Além disso, concluiu-se que há uma tendência positiva entre o aumento da frequência e magnitude das inundações e as transgressões nos sistemas hidromorfológicos pela urbanização. Dessa forma, as derivações antrópicas são variáveis indispensáveis para o entendimento das tendências espaço-temporais das inundações em bacias hidrográficas urbanizadas. / Based on the methodological procedures of Anthropogenic Geomorphology (RODRIGUES 1997a, 1997b, 2004, 2005 and 2010) and the approach of the Urban Historical Geomorphology, this work aims to evaluate the correlation between urban interventions in hydromorphological systems and spatial trends and frequency of flooding in the Mooca Stream basin. For this evaluation and for the recognition of original hydromorphological processes trends were generated a map of the original morphology on the scale of 1:25,000 and land use maps from different years (1952, 1962, 1972, 1994 and 2008). Those maps were used to investigate the cumulative history of urban interventions and obtain data from morphological indicators and surface materials for assessing the impacts of urbanization (RODRIGUES, 2010). Flood events that occurred in the Mooca Stream basin between the years 1971 and 2011, were also identified based on newspaper reports of Gazeta da Vila Prudente and Folha de Vila Prudente. The 85 flood events identified in the historical survey were mapped and their information were systematized in framework geoindicators changes. Based on this systematic indicators were selected for the assessment of natural and anthropogenic variables on the occurrence of floods. The results obtained allowed us to evaluate the occurrence of floods in particular sectors of the old floodplain where original morphology probably were potentiated by anthropogenic morphology. It was also found that the flood events reported over 40 years were more frequent in total daily precipitation of up to 60 mm, and 82.5% occurred between 0.1 and 15 mm. Furthermore, the major positive correlationshipe between the analised variables is the frequency and magnitude of floods with the rate of spatial transgressions in hydromorphological systems by urbanization. Thus it was concluded that more studies that discriminate in the derivations anthropogenic are indispensable for modeling and understanding the spatial and temporal trends of flooding in urbanized watersheds.

L’aire de distribution des espèces est conditionnée à la fois par des facteurs biotiques et abiotiques et ses frontières dépendent généralement des limites physiologiques de l’espèce. Ainsi, en bordure d’aire de répartition, les populations se caractérisent par une diversité génétique moindre ainsi qu’une forte différentiation génétique et leur existence dépend d’un équilibre fragile entre événements de colonisation et d’extinction.Depuis les années 1970, l’augmentation et l’accélération des pressions anthropiques exercées sur les écosystèmes bouleversent ces équilibres et des modifications de l’aire de répartition sont observées chez certaines espèces dont le bivalve Macoma balthica, espèce clé des écosystèmes littoraux en Europe, dont la limite sud de répartition s’est décalée vers le nord-est au cours des quarante dernières années.Afin d’évaluer les capacités adaptatives de M. balthica et dans un but de conservation, deux approches complémentaires ont été menées dans des environnements contrastés qui ont permis de mettre en évidence des signes d’adaptation locale.D’une part, l’étude du génome neutre à l’aide des outils méthodologiques et concepts de la génétique des populations a permis d’inférer l’histoire démographique de l’espèce avec une attention particulière portée sur une baie en limite d’aire de répartition (Baie de Marennes Oléron, France) et sur une baie soumise à de fortes pressions physico-chimiques (Baie de Gdansk, Pologne). Nous avons mis en évidence notamment :(i) un polymorphisme significatif dans les populations en limite d’aire en opposition avec les attendus théoriques(ii) des ruptures au flux de gènes dans le golfe de Gascogne soumis au réchauffement des eaux de surface mais aussi le long d’un gradient environnemental dans la baie de Gdansk. D’autre part, l’étude moléculaire de la sélection a été menée par la méthode de pyroséquençage sur le transcriptome d’individus prélevés en milieux contrastés. Cette étude a permis de mettre en évidence des tendances d’expression différentielle de gènes de réponse générale au stress selon le milieu considéré. / Species distribution is conditioned by biotic and abiotic factors and its borders depend generally on physiological limits of species. At the edge of their distribution, populations are characterized by a less genetic diversity as well as a strong genetic differentiation and their existence depends on a fragile balance between colonization and extinction.Since the 1970s, the increase and the acceleration of the anthropological pressures exercised on ecosystems upset this balance. As a consequence, modifications of many species distributions are observed. As an example, the south end of the distribution of the bivalve Macoma balthica, a key species of the european littoral ecosystems has moved towards the northeast during the last forty years.In order to conserve this species, we need to estimate the adaptive capacities of M. balthica. Two complementary approaches were undertaken in contrasting environments. The neutral genome was studied using population genetics methods to the demographic history of the species with a particular attention at the edge of its distribution (Bay of Marennes Oléron, France) and in a bay subjected to strong physico-chemical pressures (Bay of Gdansk, Poland). We brought to light in particular:1) A significant polymorphism in the populations at the edge of the distribution in contrast to theoretical predictions.2) A geneflow rupture correlated with high sea surface temperature (in the Bay of Biscay) and also along an environmental gradient ( derived from multiple parameters) in the bay of Gdansk.The molecular study of natural selection was conducted by the method of pyroséquençage using transcriptome from individuals at specific locations. This study allowed us to bring to light tendencies of differential gene expression implicated in the general response to stress.

Master of Science / Department of Biology / Craig Paukert / I investigated the influence of anthropogenic threats and hydrologic alteration on fish assemblages within the Lower Colorado River Basin (LCRB). Life history traits of fish assemblages for individual stream segments were summarized by species presence/absence data of current (1980-2006) records. To assess anthropogenic threats, I developed a series of ecological risk indices at various scales (e.g., catchment, watershed, aquatic ecological system and upstream of aquatic ecological system) and related each index to fish life-history traits to determine the method and scale that best related to biotic metrics. Hydrologic alteration was quantified using the Indicators of Hydrologic Alteration software to calculate hydrologic alteration values using the range of variability approach. Ecological risk indices within all scales were strongly correlated (r[superscript]2>0.54, p<0.0001) to one another. Relationships between fish life history traits and ecological risk indices occurred only at the catchment and watershed scales. Strongest relationships were at the watershed scale where increased levels of anthropogenic risk were related to reduced occurrences of native, fluvial dependent species (r[superscript]2=0.12, p<0.0001) and increased occurrences of nonnative generalist species (r[superscript]2=0.22, p<0.0001). The percent agriculture was positively related to indices of alteration of low flows (r=0.401, p=0.006) while forested land cover was negatively related to alteration of low flow events (r=-0.384, p=0.008). Relationships between indices of hydrologic alteration and fish traits indicate the occurrence of piscivorous, nonnative fishes increased with alteration of low flow events whereas occurrence of fluvial dependent fishes that preferred rubble substrate decreased with alteration of low flow events (r=0.64, p=0.001). Our analysis suggests that ecological risk indices and hydrologic alteration in the LCRB are related to composition of biotic communities. Incorporating cost-effective risk indices into conservation planning will likely increase the effectiveness of conservation efforts while understanding biotic responses to modified flow regimes are a necessity in sustainable development of water resources as human populations grow and water resources decrease in the LCRB.

Seagrasses are considered highly important CO2 sinks, with the capacity to store substantial quantities of organic carbon in the living biomass and sediments, and thereby acting as a buffer against climate change. In this thesis, I have studied carbon storage variability in temperate and tropical seagrass habitats and identified factors influencing this variation. In addition, as seagrass areas are decreasing worldwide, I have assessed effects of different anthropogenic disturbances on carbon sequestration processes. The result from this thesis showed that there was a large variation in carbon storage within and among temperate, tropical and subtropical regions. The highest organic carbon stocks were found in temperate Zostera marina meadows, which also showed a larger carbon storage variability than the subtropical and tropical seagrass habitats. The tropical and subtropical seagrass meadows had inorganic carbon pools exceeding the organic carbon accumulation, which could potentially weakens the carbon sink function. The variability in organic carbon stocks was generally strongly related to the sediment characteristics of the seagrass habitats. In Z. marina meadows, the strength of the carbon sink function was mainly driven by the settings of the local environment, which in turn indicates that depositional areas will likely have higher organic carbon stocks than more exposed meadows, while in the tropics seagrass biomass was also influencing sedimentary carbon levels. Furthermore, locations with large areas of seagrass were associated with higher carbon storage in tropical and subtropical regions, which could be related to increased accumulation of both autochthonous and allochthonous carbon. In an in situ experiment, impacts on carbon sequestration processes from two types of disturbances (with two levels of intensity) were tested by simulating reduced water quality (by shading) and high grazing pressure (through removal of shoot biomass). At high disturbance intensity, reductions in the net community production and seagrass biomass carbon were observed, which negatively affected carbon sequestration and could impact the sedimentary organic carbon stocks over time. In the treatments with simulated grazing, erosion was also seen, likely due to an increase in near-bed hydrodynamics. When experimentally testing effects of increased current flow on organic carbon suspension in Z. marina sediment, a ten-fold release of organic carbon with higher current flow velocities was measured, which resulted in an increase in the proportion of suspended organic carbon by three times in relation to other sediment particles. Therefore, periods with enhanced hydrodynamic activity could result in a removal of organic carbon and thereby likely reduce the seagrass meadows’ capacity to store carbon. The findings of this thesis add to the emerging picture that there is a large natural variability in seagrasses’ capacity to store carbon, and highlight how human-induced disturbances could negatively affect the carbon sink function in seagrass meadows. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

Anthropogenic environmental changes can serve as drivers for evolutionary responses in wild populations. To predict the long-term impact of anthropogenic changes on populations, it is crucial to understand the genetic effects caused by these disturbances. The Baltic Sea is considered to be one of the world’s most contaminated seas, and the increase of anthropogenic chemical pollution is a major threat to its ecosystems. This thesis assesses the impact of harbors and sewage treatment plants on physiological traits and genetic structure of resident populations of blue mussels at replicated sites in the Baltic Sea. The initial evaluation of the overall genetic pattern in blue mussel populations in the Swedish West Coast, the Baltic Proper and the Bothnian Sea found genetic differentiation between the three water basins and a low genetic differentiation within each basin, especially within the Baltic Proper. Despite the low genetic differentiation among blue mussels within the Baltic Proper, a parallel genetic differentiation associated with sewage treatment plant effluents was found in this basin. This included genomic regions with a high degree of differentiation between reference sites and sites affected by sewage plants effluent. This genetic differentiation is suggested to be due to post-dispersal selection acting in each generation. In contrast, no parallel genetic differentiation was associated with harbors. We identified five genomic regions in blue mussels, showing strong signs of selection, shared among three out of four replicated reference sites and sites affected by sewage effluents in the Baltic Proper i.e. Askö, Tvärminne and Karlskrona. An initial characterization of these genomic regions revealed functions related to immune and endocrine responses, oxidative stress and shell formation. Our results indicate that selection caused by sewage effluents involves multiple loci. The same genomic regions are found across different locations in the Baltic Proper but there are also unique genomic regions at each location. No genotoxic or histopathological effects were found among blue mussels from sewage effluent-affected areas but a higher frequency of histological abnormalities in the digestive gland were observed in mussels from harbors. / Evolutionära anpassningar till miljöstörningar i marina ekosystem: genetisk ekotoxikologi i Östersjön