<p> During the summer of 1970 a study was initiated to define factors controlling the biosphere in the lentic environment of the Precambrian Shield. Data were collected from nine lakes of varying size and depth located in a number of geological formations. Chemical, physical and biological conditions in these lakes were investigated at two sampling periods and the lakes were classified on the basis of morphology (surface area to volume area) and lithology (surficial and bedrock geology). Attempts were made to determine the influence of morphology and lithology on the chemical and biological conditions observed. Emphasis was placed on the relationships of these factors to aspects of the primary and secondary trophic levels in the lentic ecosystem including primary productivity and the standing crop and diversity of phytoplankton and zooplankton.</p> <p> The atmosphere, a third potential factor influencing lakes was investigated by means of a network of air monitoring stations (collecting both precipitation and 'dry fallout') located throughout the greater Sudbury area.</p> <p> The results of the study indicated that: 1. the lentic ecosystem in the Precambrian Shield area studied can be defined by simple chemical and physical variables. 2. the morphology of the lake basins (surface area to volume ratio) modified by lithology (primarily the presence or absence of limestone) is the major factor influencing biological activity. Lakes with a low surface area to volume ratio showed low productivity while lakes with a high surface area to volume ratio showed nigh productivity. Silica and calcium concentrations (influenced by the lithosphere) were important since relatively small changes in the concentration of these chemical species stimulated a response in the biosphere. 3. some of the lakes were affected by concentrations of sulphates conveyed to the water by the atmosphere. Observed effects included increases in the hydrogen ion concentration in lakes with low calcium concentrations (poorly buffered) and a depression of the diversity of both primary and secondary trophic levels.</p> / Thesis / Master of Science (MSc)

Ponds are common and abundant features in nearly all landscapes typical of European lowland landscapes yet research on freshwater biodiversity has traditionally focussed on larger waterbodies such as lakes and rivers. This has led to an increased need to understand and quantify the biodiversity associated with pond habitats to better inform the active conservation and management of these small waterbodies. This thesis examines the aquatic macroinvertebrate biodiversity (alpha, beta and gamma) and conservation value of 95 ponds in Leicestershire, UK, across a variety of urban and rural landscape types and at a range of spatial scales. In addition, the relative importance of local (physicochemical and biological) and spatial (connectivity) variables in structuring macroinvertebrate communities within ponds is investigated. At a regional scale, the greatest macroinvertebrate biodiversity and conservation value was recorded within meadow ponds compared to urban, agricultural and forest ponds. Spatially, ponds were highly physically and biologically heterogeneous. Temporally (seasonally), invertebrate communities were most dissimilar in meadow and agricultural ponds but assemblages were similar in urban and forest ponds. In urban landscapes, park ponds supported a greater diversity of invertebrates than other urban or garden ponds and typically had a greater conservation value. Garden ponds were the most taxon poor of those investigated. Perennial floodplain meadow ponds supported a greater biodiversity of invertebrates compared to ephemeral meadow ponds although conservation value was similar. Despite regular inundation from the River Soar, ephemeral ponds supported distinct communities compared to perennial meadow ponds. Aquatic macrophytes supported a higher diversity of taxa than other pond mesohabitats across all landscapes studied. Physicochemical factors were identified to be the dominant influence on macroinvertebrate assemblages although, a combination of local and spatial factors best explained the variation in community composition at a regional scale and for meadow ponds. Spatial factors were not identified to significantly influence urban pond communities. This study highlights the ecological importance and conservation value of ponds in rural and anthropogenically disturbed landscapes. Recognition of the significant contribution of ponds to freshwater biodiversity at regional and landscape scales is important for future conservation of pond habitats and will help focus and direct conservation strategies to where they are needed most.

Orientador: Carmem Silvia Fontanetti Christofoletti / Banca: Maria Aparecida Marin Morales / Banca: Silvia Tamie Matsumoto / Resumo: A degradação dos recursos hídricos, como os ambientes lênticos, dentre eles, os lagos, é uma das maiores preocupações atualmente, visto que esta pode causar danos diretos ou indiretos à saúde e à sobrevivência dos organismos expostos. Um dos fatores que contribui para a alteração da qualidade das águas de ambientes lênticos é o despejo de efluentes, principalmente àqueles de origem doméstica, portadores de substâncias que chegam a ser tóxicas para o meio aquático. Por meio dos testes citogenéticos, utilizando os mais diversificados organismos-teste, é possível biomonitorar a extensão da poluição e avaliar os efeitos dessas substâncias presentes no ambiente natural. Com esse intuito, o presente trabalho tomou por modelo de estudo, um lago urbano artificial (Lago Azul, Rio Claro-SP) e objetivou avaliar o potencial citotóxico, genotóxico e mutagênico das águas desse ambiente, por meio dos testes de aberrações cromossômicas e micronúcleos, em células meristemáticas de Allium cepa (cebola), em dois tratamentos: o contínuo e o período de recuperação, em água ultra pura; e, pelo teste do micronúcleo associado às anormalidades nucleares e do ensaio do cometa, aplicados em eritrócitos de Oreochromis niloticus (tilápia). Coletas de águas sazonais foram realizadas na estação seca (agosto/2006 e agosto/2007) e na estação chuvosa (março/2007 e fevereiro/2008). Análises físico-químicas foram feitas para uma coleta de cada estação. A partir dos dados obtidos, pode-se inferir que as águas desse ambiente lêntico apresentam potencial citotóxico, genotóxico e mutagênico, nas duas estações de coletas, para os dois organismos-teste empregados. As análises de metais revelaram concentrações acima do permitido pela legislação de Ag, Cd2+, Cu e Fe3+, em ambas as estações. Embora os... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The degradation of water resources, as the lentics environments, among them, the lakes, is a major concern now, because it can cause direct or indirect damages to health and to the survival of the exposed organisms. One factor that can contribute to change the water quality of lentics environments is the dumping of effluents, mainly those of domestic origin, carriers of substances that come to be toxic to the aquatic environment. Through the cytogenetic tests, using the most diverse systems-test, it is possible monitoring the extent of pollution and assess the effects of substances on the natural environment. To that end, this work has taken a model of study, an urban artificial lake (Lago Azul, Rio Claro-SP) and aimed to evaluate the cytotoxic, genotoxic and mutagenic potentials of waters that environment, through tests of chromosome aberrations and micronuclei in meristematic cells of Allium cepa (onion) in two treatments: the continued and the period of recovery, in ultra pure water, and by the micronucleus and nuclear abnormalities test and of the comet assay, applied in erythrocytes of Oreochromis niloticus (tilapia). Seasonal collections of waters were held in the dry season (august/2006 and august/2007) and the rainy season (march/2007 and february/2008). Physical and chemical analyses were made for a collection of each season. From the data obtained, it can be infered that the waters of this lentic environment had cytotoxic, genotoxic and mutagenic potentials in two seasons of collections for the two systems-test employed. Analyses of metals detected high concentrations of Ag, Cd2+, Cu, Fe3+, whose values are higher than permitted by law, in both seasons. Although the cytotoxic, genotoxic and mutagenic potentials have been detected in two seasons, the dry season is that presented the highest risk... (Complete abstract click electronic access below) / Mestre

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-10-05T21:36:43Z No. of bitstreams: 1 Tese final - ADRIANO.pdf: 2461586 bytes, checksum: 48e769e7d6c00fd91d7097d08526ba89 (MD5) / Made available in DSpace on 2017-10-05T21:36:43Z (GMT). No. of bitstreams: 1 Tese final - ADRIANO.pdf: 2461586 bytes, checksum: 48e769e7d6c00fd91d7097d08526ba89 (MD5) Previous issue date: 2017-03-29 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Over the past few years, lentic environments have been suffering from the degradation of the quality and quantity of their waters, due to intense anthropogenic activity. However, studies from the analyses of heavy metals in water, sediments and aquatic macrophytes constitute one of the fundamental steps for lentic environment management and monitoring, since they represent major natural resources for various activities in the economy, health, landscaping, and even in the cycling of nutrients. As a part of this ecosystem, the aquatic macrophytes can, due to their great production of biomass, be reused in agriculture as organic fertilizers by means of composting. Organic fertilizers exert great physical, chemical, and biological benefits to the soil and vegetation. However, the heavy metals that come from fertilized chemicals, when used indiscriminately, can accumulate in excess in the tissue of aquatic macrophytes. This can make their use as organic fertilizers inviable, because they can be translocated to the edible parts of the vegetation, such as the bean grains, causing serious health risks to humans and animals. In this sense, this work had as an aim: quantify the level of heavy metals in the compartments (water, sediments, Salvinia auriculata, and Cabomba caroliniana) from the Marimbus wetlands; characterize the organic fertilizers stemming from aquatic macophytes and determine the presence of the heavy metals Pb and Cd in the bean grains according to the relevant legislation for each material. Samples were collected from water, sediments, S. auriculata and C. caroliniana. The process of aerobic composting with macrophytes was done in which the levels of pH, temperature, nutrients and humidity were analyzed. The planting of the common bean (Phaseolus vulgaris L.) was effectively implemented with organic fertilizers coming from the macrophytes. Subsequently, in each step, heavy metals were analyzed in samples of water, sediments, Salvinia auriculata, Cabomba caroliniana, organic fertilizers and bean grains through the air-acetylene flame atomic absorption spectrophotometry method. In relation to water and sediments, the results obtained showed that the levels of heavy metals are within the limits established by the current legislation. The raw materials used as substrates in the composting showed satisfactory physical and chemical parameters as organic components to be applied in agricultural activities. As to the presence of heavy metals in bean grains, a Ph was detected with inadequate levels for human consumption. Thus, it was concluded that the macrophytes are of vital importance to guarantee the various uses of water in the hydric sources as well as viable for the production of organic fertilizers, but they should be used in agriculture with restrictions. / Ao longo dos ?ltimos anos, os ambientes l?nticos v?m sofrendo com a degrada??o da qualidade e quantidade de suas ?guas, devido ? intensa atividade antr?pica. Os estudos das an?lises de metais pesados em ?gua, sedimento e macr?fitas aqu?ticas constituem um dos passos fundamentais para o gerenciamento e monitoramento dos ambientes l?nticos, visto que eles representam grandes riquezas naturais para diversas atividades na economia, na sa?de, no paisagismo e at? mesmo na ciclagem de nutrientes. Como parte deste ecossistema encontram-se as macr?fitas aqu?ticas que devido a sua grande produ??o de biomassa, podem ser reutilizadas na agricultura como composto org?nico por meio da compostagem. Os compostos org?nicos exercem grandes benef?cios f?sicos, qu?micos e biol?gicos ao solo e aos vegetais. Contudo, os metais pesados provenientes dos fertilizantes qu?micos, quando usados indiscriminadamente, podem ser acumulados em excesso nos tecidos de macr?fitas aqu?ticas. Isso pode inviabilizar seu uso como composto org?nico, pois podem ser translocados para as partes comest?veis dos vegetais como frutos e sementes causando s?rios riscos a sa?de do homem e dos animais. Neste sentido, este trabalho teve como objetivo quantificar o teor de metais pesados dos compartimentos (?gua, sedimento, Salvinia auriculata e Cabomba caroliniana) do Pantanal dos Marimbus, caracterizar os compostos org?nicos provenientes das macr?fitas e determinar a presen?a dos metais pesados Pb e Cd nos gr?os de feij?o em fun??o das legisla??es pertinentes para cada material. Foram coletadas as amostras de ?gua, sedimento, S. auriculata e C. caroliniana. Realizou-se o processo de compostagem aer?bia com as macr?fitas no qual foram analisados os teores de pH, temperatura, nutrientes e umidade. Realizou-se o plantio de feij?o comum (Phaseolus vulgaris L.) com compostos org?nicos proveniente das macr?fitas. Posteriormente a cada etapa, foram analisados os metais pesados nas amostras de ?gua, sedimento, Salvinia auriculata, Cabomba caroliniana, compostos org?nicos e gr?os de feij?o pelo m?todo de Espectrofotometria de absor??o at?mica de chama ar-acetileno. Em rela??o ? ?gua e sedimento, os resultados obtidos evidenciaram que os teores de metais pesados est?o dentro dos limites pela legisla??o vigente. As mat?rias primas utilizadas como substratos na compostagem apresentaram par?metros f?sicos e qu?micos satisfat?rio como compostos org?nicos para serem aplicados nas atividades agr?colas. J? com rela??o ? presen?a de metais pesados nos gr?os de feij?o, foi detectado Pb com limites inadequados para consumo humano. Dessa forma, concluiu-se que as macr?fitas s?o de vital import?ncia para garantir os diversos usos da ?gua no manancial h?drico e vi?veis para produ??o de compostos org?nicos, por?m podem ser utilizados na agricultura com restri??es.

A etnoictiologia busca descrever e valorizar os conhecimentos dos pescadores artesanais, atravÃs de estudos que evidenciam que estes sÃo portadores de conhecimentos bioecolÃgicos acerca dos peixes que capturam. Desta forma, objetivou-se comparar os conhecimentos etnoictiolÃgicos dos pescadores artesanais dos aÃudes pÃblicos Araras e Edson Queiroz (bacia do mÃdio rio AcaraÃ-CE) com a literatura cientÃfica. Com este fim, selecionou-se uma populaÃÃo representativa para cada um destes aÃudes. Assim, tem-se a Ilha de EsaÃ, para o aÃude Araras, e Vila SÃo Cosme, para o Edson Queiroz. Foram realizadas observaÃÃo participante, entrevistas semiestruturadas, estÃmulo visual e turnÃs-guiadas com pescadores destas populaÃÃes. Foram entrevistados vinte pescadores na Vila SÃo Cosme e vinte e quatro na Ilha de EsaÃ. As entrevistas abordaram aspectos etnoecolÃgicos das principais espÃcies de peixes capturadas pelos pescadores. Foram citadas vinte etnoespÃcies de peixes e uma de camarÃo como sendo capturadas nos aÃudes. Dentre estas, as mais importantes, economicamente, foram: carÃ-tilÃpia (Oreochromis niloticus Linnaeus, 1758 e Tilapia rendalli Boulenger, 1897), curimatà (Prochilodus brevis Steindachner, 1874), pescada, (Plagiossion squamossimus Heckel, 1840), piau (Leporinus sp.), traÃra (Hoplias brasiliensis e H. malabaricus Bloch, 1794) e tucunarà (Cichla cf. ocellaris Bloch; Schneider, 1801). Na classificaÃÃo da ictiofauna, os pescadores utilizam aspectos morfolÃgicos e etolÃgicos, apresentando vÃrias etnoespÃcies com nomes genÃricos e poucas com nomes binomiais. Em sua dieta, estas populaÃÃes consomem peixes, como principal fonte de proteÃna animal, havendo restriÃÃes por carÃter social e cultural. Quanto à etnoictiologia, conclui-se que os pescadores possuem conhecimentos consistentes sobre a ecologia geral, trÃfica e reprodutiva da ictiofauna capturada, vivenciando empiricamente muitas das informaÃÃes presentes na literatura acadÃmica. Logo, pela consistÃncia dos saberes dos pescadores da Ilha de Esaà e da Vila SÃo Cosme, estes conhecimentos podem contribuir para futuros estudos cientÃficos e ser incorporados na elaboraÃÃo de planos de gestÃo e manejo sustentÃvel dos recursos hÃdricos e pesqueiros da regiÃo mÃdia do AcaraÃ. / The ethnoictiology to describe and use the knowledge of fishermen, by studies that show that they are carriers of bio-ecological knowledge about fish they catch. Thus, the objective was to compare the knowledge of fishermen of public dams Araras and Edson Queiroz (Middle Acaraà River Basin, CearÃ) with the scientific literature. With this end, we selected a representative population for each of these reservoirs. Therefore, there is the Ilha de EsaÃ, for the dam Araras, and Vila SÃo Cosme, to Edson Queiroz. Were performed participant observation, semi-structured interviews, visual stimulus, and guided fishing tours of these populations. Twenty fishermen were interviewed in Vila Sao Cosme and twenty-four on the Ihla de Esaà The interviews aspects ethnoecological of the main fish species caught by fishermen. Were cited twenty ethnospecies fish and shrimp as captured in the reservoirs. Among these, the most important, economically, are carÃ-tilapia [Oreochromis niloticus (Linnaeus, 1758) and Tilapia rendalli (Boulenger, 1897)], curimatà [(Prochilodus brevis (Steindachner, 1874)], pescada [Plagiossion squamossimus (Heckel, 1840)], piau (Leporinus sp.),traÃra (Hoplias brasiliensis e H. malabaricus) and tucunarà [Cichla cf. ocellaris (Bloch; Schneider, 1801)]. In the classification of fishes, fishemen used morphological and ethological aspects, presenting several ethnospecies with generic names and few with binomial names. In your diet, these populations consume fish as the main source of animal protein, with social and cultural restrictions. As for ethnoictiology, it is concluded that the fishermen have consistent knowledge about the general ecology, trophic and reproductive of fishes captured. Therefore, the consistency of the knowledge of fishermen on the Ilha de Esaà and Vila SÃo Cosme, this knowledge can contribute to future scientific studies and be incorporated in the preparation of management plans and sustainable management of water resources and fisheries in the middle region AcaraÃ.

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No. of bitstreams: 2 Dissertação - Vilson Sousa Queiroz Júnior 0 2016.pdf: 9304635 bytes, checksum: 577b278694a194be0898f039d64e4c5a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The natural change of river courses for the construction and reservoir formation, represented here for power generation given the growing demand for electricity in Brazil, causes significant changes in aquatic environments and consequently in its surroundings, given the different characteristics depending, of flooded areas, the different types of water circulation, the period of residence, the flow of nutrients, in synthesis, limnological, standards setting different aquatic compartments, suggesting a certain importance for these environments. The Limnological analyses of the waters of a reservoir associated with remote sensing techniques in order to identify the aquatic compartments represents a set methodology effective for desired results. In this context, the objective of this study was to perform the characterization of aquatic compartments HPP reservoir Caçu, Goiás Brazil, limnological variables and spectral data associated with an analysis of the dynamics of land use in the catchment area of Caçu. Analyzing two distinct periods, being one with the lowest rainfall, represented by the month of August 2014 and the highest rates, the month of January 2015 as climatological average. The methodology consisted in collecting rainfall data, the concentration of suspended solids (CSS), transparency of the water through the Secchi disk (DS), chlorophyll-a (CHL-a) and land use classification. Spectral data were collected FieldSpec ® HandHeld 2. Limnological data collection and the Spectra was carried out in 35 sampling points evenly distributed by the reservoir. Limnological variables were espacializadas by the Inverse distance weighting (IDW). The use of the land was made through satellite image classification of Landsat 8 OLI, obtaining as predominant class the average value for grazing the fields of 74.11%, followed by the class of vegetation with 19.91%. The results showed that the accumulated precipitation for the period of January showed the highest field and the field of August the lowest rainfall. The CSS presented variation of 0.17 to 4.5 mg/L for the August to January to 18.83 0.5 mg/L. The transparency of the DS was, of the 2.5 m 0.9, to August and January to 1.60 0.5 m. To the CHL – in the field of August was found values of 0.0 to 6.32 μ g/L and for January to 1.26 8.84 μ g/L, with values ranging along the reservoir, going on with low values and other with high values (compared to the previous part), for both fields. For Limnological variables was executed Person correlation tests to understand the interdependencies of these, getting Strong inverse correlation to CSS and DS and Moderate correlation for CSS and CHL-a. For the spectra obtained in the field, in general all showed similar behavior, varying only the rates of between 0.5% reflectance and 2.5% for August and 0.3% and 3.4% and certain peculiarities. It was possible to observe that there are absorption features, being approximately in 610 and 675nm, the latter being for chlorophyll-a. According to the literature, the 610 nm absorption band is due to absorption by phycocyanin. Presented to the CSS, spectral response in the red and near-infrared bands. In general, the results and based on the variables of greater relevance as DS, CSS and CHL, the reservoir of Caçu presented three compartments defined Dryland, transition and Lentic stretches, A and B data peculiarities of Limnological variables patterns. / Alteração natural dos cursos de rios para a construção e formação de reservatórios, aqui representado para a geração de energia dado a crescente demanda de energia elétrica no Brasil, acarreta mudanças significativas nos ambientes aquáticos e consequentemente no seu entorno, dado as distintas características em função, das áreas inundadas, dos diversos tipos de circulação da água, do período de residência, do fluxo de nutrientes, em síntese, dos padrões limnológicos, definindo diferentes compartimentos aquáticos, sugerindo certa importância de estudos para estes ambientes. A análise limnológica das águas de um reservatório associadas a técnicas de sensoriamento remoto com o intuito de identificar os compartimentos aquáticos representa um conjunto metodológico eficaz para resultados almejados. Neste contexto, o objetivo do presente trabalho foi realizar a caracterização dos compartimentos aquáticos do reservatório da UHE Caçu, Goiás, Brasil, por variáveis limnológicas e dados espectrais associado a uma análise da dinâmica do uso da terra da bacia hidrográfica da UHE Caçu. Analisando dois períodos distintos, sendo um com os menores índices pluviométricos, representado pelo mês de agosto de 2014 e o de maiores índices, o mês de janeiro de 2015 conforme média climatológica. A metodologia constituiu-se na coleta de dados de precipitação, Concentração de Sólidos em Suspensão (CSS), transparência da água por meio do Disco de Secchi (DS), Clorofila – a (CHL – a) e classificação do uso da terra. Os dados espectrais foram coletados FieldSpec® HandHeld 2. A coleta de dados limnológica e dos espectros foi realizada em 35 pontos amostrais distribuídas uniformemente pelo reservatório. As variáveis limnológicas foram espacializadas pelo Inverso do Quadrado da distância (IDW). O uso da terra foi confeccionado por meio de classificação de imagens de satélite do Landsat 8 OLI, obtendo-se como classe predominante a de Pastagem com valor médio para os campos de 74,11%, seguido pela classe de Vegetação com 19,91%. A partir dos resultados observou-se que a precipitação acumulada para o período do campo de janeiro apresentou maior e para o campo de agosto o menor índice pluviométrico. A CSS apresentou variação de 0,17 a 4,5 mg/L para o campo de agosto, para janeiro de 0,5 a 18,83 mg/L. A transparência do DS ficou, de 0,9 a 2,5 m, para agosto e para janeiro de 0,5 a 1,60 m. Para a CHL – a no campo de agosto foi encontrado valores de 0,0 a 6,32 μg/L e para janeiro de 1,26 a 8,84 μg/L, com padrão de valores variando ao longo do reservatório, havendo partes com valores baixos e em outras com valores altos (se comparado a parte anterior), para ambos os campos. Para as variáveis limnológicas foi executado testes de correlação de Person para compreender a interdependências destas, obtendo correlação inversa Forte para CSS e DS e correlação Moderada para CSS e CHL - a. Para os espectros obtidos em campo, no geral todos apresentaram comportamento semelhante, variando apenas as taxas de reflectância entre 0,5% e 2,5% para agosto e 0,3% e 3,4% e certas particularidades. Foi possível observar que há feições de absorção, sendo, aproximadamente em 610 e 675nm, sendo esta última para a Clorofila – a. Segundo a literatura, a banda de absorção em 610 nm é devida à absorção pela ficocianina. Apresentou resposta espectral para o CSS, nas faixas do vermelho e infravermelho próximo. De forma geral a partir dos resultados tendo-se como base as variáveis de maior relevância como DS, CSS e CHL - a, o reservatório da UHE Caçu apresentou três compartimentos definidos, Lótico, Transição e Lêntico A e B dados as suas particularidades de padrões das variáveis limnológicas.

Made available in DSpace on 2014-06-11T19:22:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-04Bitstream added on 2014-06-13T20:49:39Z : No. of bitstreams: 1 christofoletti_ca_me_rcla.pdf: 3763933 bytes, checksum: d9284f200972936e72e67bb3de745be4 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A degradação dos recursos hídricos, como os ambientes lênticos, dentre eles, os lagos, é uma das maiores preocupações atualmente, visto que esta pode causar danos diretos ou indiretos à saúde e à sobrevivência dos organismos expostos. Um dos fatores que contribui para a alteração da qualidade das águas de ambientes lênticos é o despejo de efluentes, principalmente àqueles de origem doméstica, portadores de substâncias que chegam a ser tóxicas para o meio aquático. Por meio dos testes citogenéticos, utilizando os mais diversificados organismos-teste, é possível biomonitorar a extensão da poluição e avaliar os efeitos dessas substâncias presentes no ambiente natural. Com esse intuito, o presente trabalho tomou por modelo de estudo, um lago urbano artificial (Lago Azul, Rio Claro-SP) e objetivou avaliar o potencial citotóxico, genotóxico e mutagênico das águas desse ambiente, por meio dos testes de aberrações cromossômicas e micronúcleos, em células meristemáticas de Allium cepa (cebola), em dois tratamentos: o contínuo e o período de recuperação, em água ultra pura; e, pelo teste do micronúcleo associado às anormalidades nucleares e do ensaio do cometa, aplicados em eritrócitos de Oreochromis niloticus (tilápia). Coletas de águas sazonais foram realizadas na estação seca (agosto/2006 e agosto/2007) e na estação chuvosa (março/2007 e fevereiro/2008). Análises físico-químicas foram feitas para uma coleta de cada estação. A partir dos dados obtidos, pode-se inferir que as águas desse ambiente lêntico apresentam potencial citotóxico, genotóxico e mutagênico, nas duas estações de coletas, para os dois organismos-teste empregados. As análises de metais revelaram concentrações acima do permitido pela legislação de Ag, Cd2+, Cu e Fe3+, em ambas as estações. Embora os... / The degradation of water resources, as the lentics environments, among them, the lakes, is a major concern now, because it can cause direct or indirect damages to health and to the survival of the exposed organisms. One factor that can contribute to change the water quality of lentics environments is the dumping of effluents, mainly those of domestic origin, carriers of substances that come to be toxic to the aquatic environment. Through the cytogenetic tests, using the most diverse systems-test, it is possible monitoring the extent of pollution and assess the effects of substances on the natural environment. To that end, this work has taken a model of study, an urban artificial lake (Lago Azul, Rio Claro-SP) and aimed to evaluate the cytotoxic, genotoxic and mutagenic potentials of waters that environment, through tests of chromosome aberrations and micronuclei in meristematic cells of Allium cepa (onion) in two treatments: the continued and the period of recovery, in ultra pure water, and by the micronucleus and nuclear abnormalities test and of the comet assay, applied in erythrocytes of Oreochromis niloticus (tilapia). Seasonal collections of waters were held in the dry season (august/2006 and august/2007) and the rainy season (march/2007 and february/2008). Physical and chemical analyses were made for a collection of each season. From the data obtained, it can be infered that the waters of this lentic environment had cytotoxic, genotoxic and mutagenic potentials in two seasons of collections for the two systems-test employed. Analyses of metals detected high concentrations of Ag, Cd2+, Cu, Fe3+, whose values are higher than permitted by law, in both seasons. Although the cytotoxic, genotoxic and mutagenic potentials have been detected in two seasons, the dry season is that presented the highest risk... (Complete abstract click electronic access below)

Made available in DSpace on 2016-06-02T19:31:36Z (GMT). No. of bitstreams: 1 DissSCE.pdf: 723485 bytes, checksum: 1757119ef02fa2dba80ba1297f9fd16b (MD5) Previous issue date: 2006-08-29 / The studied lake (Lagoa Mayaca) is located in a preservation area at the campus of the Universidade Federal de São Carlos. With the aim of analyzing the dynamic and the taxonomic composition of the Chironomidae, samples were taken through a transversal transect in two different periods (dry and wet season), comprehending the phenological cycle of Mayaca fluviatilis Aublet, 1775. From a total of 27 Chironomidae taxa, it was verified that the most abundant taxa in the dry season were: Cladopelma, Caladomyia sp1, Caladomyia riotarumensis, Djalmabatista pulcher, Ablablesmyia (Karelia), Tanytarsus rhabdomantis e Labrundinia. On the other hand, in the wet season the most representative were: Polypedilum (Asheum), Chironomus, Goeldichironomus, Endotribelos, Tanytarsus rhabdomantis, Caladomyia friederi, Ablablesmyia (Karelia), Labrundinia e Cricotopus. The greater taxonomic richness and number of specimens were registered in the sampled sites where Mayaca fluviatilis was present, indicating that the presence of this macrophyte was very important for structuring the studied community. / A lagoa estudada (Lagoa Mayaca) situa-se em uma área de preservação, dentro do campus da Universidade Federal de São Carlos. Com o objetivo de analisar a composição e a dinâmica taxonômica de Chironomidae, as coletas foram realizadas ao longo de um transecto transversal, em duas épocas distintas (estação de seca e de chuva), compreendendo o ciclo fenológico de Mayaca fluviatilis Aublet, 1775. Do total de 27 táxons de Chironomidae identificados, constatou-se que numericamente os táxons mais representativos para o período de estiagem foram: Cladopelma, Caladomyia sp1, Caladomyia riotarumensis, Djalmabatista pulcher, Ablablesmyia (Karelia), Tanytarsus rhabdomantis e Labrundinia. Já no período de chuva destacaram-se Polypedilum (Asheum), Chironomus, Goeldichironomus, Endotribelos, Tanytarsus rhabdomantis, Caladomyia friederi, Ablablesmyia (Karelia), Labrundinia e Cricotopus. A maior riqueza taxonômica e número de exemplares foram registrados nos pontos amostrais com presença de Mayaca fluviatilis, indicando que a presença desta macrófita foi de fundamental importância na estruturação da comunidade de larvas de Chironomidae estudada.

Juvenile rainbow trout Oncorhynchus mykiss stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by (1) direct observations (snorkel transects) of habitat selection in two reservoirs and (2) measurements of survival and growth rates in a pond experiment where adult brown trout Salmo trutta were predators. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day, juvenile trout were abundant in complex inshore habitats and avoided simple habitats such as sand and gravel. Measurements of gut fullness indicated that juvenile trout fed during the day but not during the night. Large Daphnia comprised more than 95% of the diet of juvenile trout. Because large Daphnia were often higher offshore than inshore in both reservoirs, selection of inshore cover is believed to be primarily a response to reduce predation risk. At night, trout in both reservoirs selected more exposed areas and rested on the bottom. In the pond experiment, the presence of brown trout significantly increased mortality of juvenile trout, decreased their growth rates, and caused them to avoid offshore areas. The presence of cover significantly decreased predation rates but did not affect growth of the juvenile trout.

Water is a limited and highly valued resource in the semi-arid Great Basin. Surface water sources are often small and widely spaced apart, comprising only 1-3% of the surface area of the overall landscape. Despite their small size, these springs and surrounding wet meadows have a substantial effect on the surrounding environment. Springs provide drinking water, forage and cover for livestock and wildlife, habitat for diversity of plant species and a resource for human-related activities. In recent years, many of these springs have become dewatered due to diversions of groundwater for municipal water and agriculture, and climatic shifts in precipitation affecting recharge. These hydrologic changes can cause a drop in the local water table that promotes a shift in the plant community from wetland-obligates to species that have more drought-tolerance. The root masses of the new plant community are insufficient to secure soils resulting in the erosion of the thalweg. This leads to channelization through the wet meadow, which drives the water table further underground. As degradation progresses, springs and wet meadows lose their ability to store water. The purpose of this thesis is to examine the responses of both the hydrologic and biologic factors to different springbox restoration techniques. Twenty-four spring sites were chosen in the Sheldon National Wildlife Refuge in northwestern Nevada. Each site was randomly assigned one of six different treatment designs. Variables for these studies included: surface soil moisture, soil moisture at varying depths, flow rates, water chemistry, plant community cover and frequency, biomass, wildlife visits and wildlife species numbers. We observed soil moisture increase over the majority of our sites, while flow rates only increased at the control sites. This may indicate that more water is being held in the soils around the spring source instead of being allowed to flow downstream. Biomass increased in four of our six treatments. All treatment types exhibited a similar effect on springs with none having a clearly more restorative effective than any others. This research suggests that springs in the Great Basin have unique characteristics and responses to restoration, and may need individualized approaches. Additionally, studies have shown that it may take many years for plant communities to recover after hydrologic restoration. Yearly variation caused by increased precipitation may be partially responsible for changes in hydrologic and biologic aspects of springs and wet meadows. Further data collection is needed to determine the true extent of treatment and yearly effects on spring restoration. In spite of the need for individualized approaches, restoration is possible. Simple solutions may be sufficient to recover hydrologic processes that maintain ecologic resilience.