Excessive nutrient loading from watersheds causes nutrient enrichment and water quality issues in very small streams to large rivers. Nutrient enrichment is exacerbated by urbanization and agricultural land use; however, the magnitude of the problem differs by regional landscape and environmental characteristics. Currently, we do not understand how regional variables moderate these relationships. Thus, the overall objective of this thesis was to investigate how regional landscape and environmental variables moderate developed land cover–stream nutrient relationships across the United States. The first study examined how climate and land use influences the scaling of phosphorus, total nitrogen, ammonia and nitrate loads for very large regions (Mid-Atlantic, Upper Mississippi, Ohio and Missouri) of the U.S. Results show the scaling relationships of nutrient loads with watershed size depends on the nutrient species and differed by region; the magnitude of the relationships was greater in wetter climates and developed watersheds. The second study determined 1) whether the relationships between urban and agricultural land cover intensity and concentrations of phosphorus, total nitrogen, ammonia and nitrate across the U.S., differed by ecoregion, and 2) whether regional landscape and environmental factors explained those differences. The relationships were found to differ by ecoregion and the differences were moderated by regional agriculture, topography and climate where stream nutrients increased more rapidly with anthropogenic land use in regions with high agricultural land use, wetter climates and flatter topography. The study findings will enable water quality managers create region-specific water management strategies for streams impacted by excessive nutrient loads. / Master of Science / Several factors affect the loading and concentration of nutrients, which in high amounts cause harmful algal blooms in streams. The size of watersheds and the level of urban and agricultural land use influence how much nutrient is added to streams. The main goal of this study was to determine how the effect of watershed size and urban and agricultural land cover on stream nutrient loading and concentrations, respectively, are controlled by particular environmental variables, such as climate, topography and land cover. To understand these effects, phosphorus, total nitrogen, ammonia and nitrate concentrations and loads were analyzed using statistical models. In the first study, the degree to which nutrient loading is affected by watershed size in four regions of the U.S. (Mid-Atlantic, Upper Mississippi, Ohio and Missouri) was assessed. The study found that the effect of watershed size on nutrient loading depended on the nutrient type and differed by region, and nutrient loads were greater in wetter climates and watersheds dominated by human activities. In the second study, regional differences in the effects of urban and agricultural land on nutrient concentrations was assessed. The study found that the effects of human land use differed by region and that these effects were greater in wetter, flatter regions, and those with a high degree of agricultural use. This study facilitates understanding and identification of important regional factors that regulate water quality in streams and therefore, will facilitate region-specific water management strategies for streams impacted by excessive nutrient loading.

Orientador: Edson Luís Piroli / Resumo: Com o crescimento da população urbana mundial, há um aumento na demanda pelo abastecimento público de água, que é fornecidapelas águas doces de rios, lagos e águas subterrâneas. Segundo a ANA (Agência Nacional de Águas, 2017), o abastecimento urbano de água foi o segundo maior usuário de recursos hídricos de água doce do Brasil em 2016. Com uma oferta finita e uma demanda crescente, muitas cidades em todo o país tem enfrentado escassez de água. Além do consumo, as atividades antrópicas em torno de áreas urbanas podem causar impactos negativos na qualidade dos recursos hídricos locais utilizados para o abastecimento, diminuindo ainda mais a disponibilidade de água doce. O objetivo desta pesquisa foi estudar a vulnerabilidade das águas subterrâneas à contaminação antrópica e identificar fontes potenciais de contaminação às águas subterrâneas e superficiais. Esta análise foi realizada no município de Jaú, São Paulo, visando identificar possíveis soluções para evitar prováveis crises de escassez de água, como as enfrentadas nos últimos anos. A área de estudo incluiu a área urbana do município e três microbacias localizadas a montante da cidade que contêm os mananciais que são utilizados para abastecimento de água. Primeiro, foi gerado um mapa de vulnerabilidade dos recursos hídricos subterrâneos que foi desenvolvido para a área usando o método DRASTIC (ALLER et al., 1987). Os resultados mostraram que 50% da área tinham uma vulnerabilidade média, enquanto 25% da área apresentavam ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: With a growing urban population globally, there is increasing demand for urban water supply and the consumption of freshwater resources from rivers, lakes, and groundwater. According to ANA (National Agency of Water, 2017), urban water supply was the second largest user of freshwater resources in Brazil in 2016. With a finite supply and an increasing demand, this is leading to water shortages in cities across the country. In addition to consuming water, human activities around urban environments can cause a degradation in the water quality of the local freshwater resources used for urban water supply, further decreasing the availability of freshwater resources. The objective of this research was to study the vulnerability of groundwater to anthropogenic contamination and identify potential sources. This analysis was carried out using in the municipality of Jaú, São Paulo in order to identify possible solutions to the water shortage crisis that it has faced in recent years. The study area included the urban area surrounding the municipality and three micro-basins located upstream of the city which contain rivers that are used for urban water supply. First, a vulnerability map of the groundwater resources was developed for the area using the DRASTIC method (ALLER et al., 1987). The results showed that 50% of the area had a medium vulnerability while 25% of the area had very high vulnerability of anthropogenic contamination in the groundwater table. Then a land use map was devel... (Complete abstract click electronic access below) / Mestre

The distribution pattern of diatoms from lakes and streams of varying salinity in the south-west of Western Australia was investigated. A total of 95 water bodies were sampled and separated into freshwater (<3 ppt), hyposaline (3-20 ppt), mesosaline (20-50 ppt) and hypersaline (>50 ppt). The south-west and specifically the inland wheatbelt region has been severely influenced by secondary salinisation, due to clearing of native vegetation for agriculture. There has been little research on diatom communities from salt-affected systems, with this data providing the basis for the development of an inference model based on species optima and tolerance limits to salinity. Physico-chemical variables measured from the study sites were collated and assessed. Salinity ranged from freshwater (0.04) to hypersaline (156.80 ppt), and pH ranged from acidic (2.90) to alkaline (10.51). Dissolved oxygen levels were recorded from 1.11 to 18.67 mgL-1, water temperature from 6.30 to 28.10 °C and peripheral vegetation scores from 1 (little or no cover) to 5 (dense cover). Analysis of variance (ANOVA) showed that salinities were significantly higher in standing waters located further inland, compared to flowing waters in high rainfall areas. Hypersaline wetlands displayed significantly lower dissolved oxygen levels, higher water temperatures and reduced peripheral vegetation, compared to freshwaters. The pH of hypersaline sites was also significantly lower, associated with surrounding land use or underlying geology. The data collected provides important baseline information, with implications for aquatic biota. / The community structure of diatoms in relation to varying salinity concentration was explored. An artificial substrate collector (JJ periphytometer) was used to standardise sampling and ensure diatom assemblages were representative of ambient water quality. A total of 217 taxa were identified with the highest diversity observed in freshwater sites (up to 33 species), and limited to less than 15 in hypersaline waters. According to BIOENV, salinity was the key factor influencing diatom community structure. SIMPER analysis found a number of discriminating taxa between salinity ranges, specifically between assemblages from freshwater and hypersaline sites. Taxa such as Achnanthidium minutissimum and Gomphonema parvulum were indicative of freshwaters. In comparison, Amphora coffeaeformis and Nitzschia ovalis were associated with hypersaline water bodies. Diatom community structure was also examined from 20 hypersaline wetlands in the wheatbelt region with varying pH. Characteristic taxa including Amphora coffeaeformis, Hantzschia sp. aff. baltica and Nitzschia ovalis showed a wide tolerance to salinity and pH, or hypersaline acidic conditions. BIOENV analysis found there were no observable differences between diatom assemblages in relation to salinities above 50 ppt and that pH was highly correlated to species composition. The increasing occurrence of acid saline lakes is of concern and is most likely attributable to deep drainage practices and continued use of fertilisers in agricultural areas. / A diatom-based transfer function was developed from the south-west dataset, to document species optima and tolerance limits to salinity. CCA analysis showed that salinity accounted for a significant and independent amount of variation in the diatom data enabling an inference model to be derived. The most successful model was generated using tolerance-downweighted weighted averaging, with a high coefficient of determination and low prediction errors that remained high after jackknifing. The optima of freshwater diatoms were similar to those reported from other regions of the world, although the optima of hypersaline species tended to be higher. Comparatively, the model performed very well, with the potential to be applied in future paleolimnological studies. In conclusion, this study has shown diatoms to be effective biomonitoring tools, providing the basis for future sampling strategies that assess the biodiversity of salt-affected water bodies in Western Australia. Potential indicator species from different salinity ranges were identified and the sensitivity of diatoms allowed for the development of a statistically robust inference model for the south-west. The reported optima and tolerance limits of important taxa may be further explored to evaluate the success of remediation measures implemented for secondary salinised systems in this region.

Northern lakes and ponds are abundant and emit large amounts of the potent climate forcer methane to the atmosphere at rates prone to change with amplified Arctic warming. In spite of being important, fluxes from surface waters are not well understood. Long-term measurements are lacking and the dominant and irregular transport mode ebullition (bubbling) is rarely quantified, which complicate the inclusion of lakes and ponds in the global methane budget. This thesis focuses on variations in emissions on both local and regional scales. A synthesis of methane fluxes from almost all studied sites constrains uncertainties and demonstrates that northern lakes and ponds are a dominant source at high latitudes. Per unit area variations in flux magnitudes among different types of water bodies are mainly linked to water depth and type of sediment. When extrapolated, total area is key and thus post-glacial lakes dominate emissions over water bodies formed by peat degradation or thermokarst processes. Further, consistent multiyear measurements in three post-glacial lakes in Stordalen, northern Sweden, reveal that seasonal ebullition, primarily driven by fermentation of acetate, can be predicted by easily measured parameters such as temperature and heat energy input over the ice-free season. Assuming that most water bodies respond similarly to warming, this thesis also suggests that northern lakes and ponds will release substantially more methane before the end of the century, primarily as a result of longer ice-free seasons. Improved uncertainty reductions of both current and future estimates rely on increased knowledge of landscape-level processes related to changes in aquatic systems and organic loading with permafrost thaw, as well as more high-quality measurements, seldom seen in contemporary data. Sampling distributed over entire ice-free seasons and across different depth zones is crucial for accurately quantifying methane emissions from northern lakes and ponds. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

A poluição de corpos d´água por metais pesados é um problema mundial, mas particularmente importante em países que apresentam atividades intensas de mineração, como o Brasil. Os contaminantes, de maneira especial aqueles conhecidos como metais pesados, podem apresentar toxicidade altíssima, como é o caso do cádmio, chumbo e outros. Por esse motivo, os efluentes industriais, quando não devidamente tratados, ainda são uma grande fonte de contaminação do ecossistema que vivemos. Diante dessa atual situação, esforços para o aprimoramento de técnicas de remoção de cátions de metais pesados da água são necessárias e podem ter impacto positivo na Saúde Pública e em outras áreas. Portanto, como solução viável e alternativa para o que já se é feito, o presente projeto propõe a produção e estudo do uso de materiais poliméricos com propriedades distintas para captação de metais pesados de soluções aquosas. Para a síntese dos polímeros foram usadas técnicas de polimerização via radical livre, e posterior hidrólise para geração de copolímeros, com o intuito de aperfeiçoar a capacidade de remoção. Os polímeros tiveram como base a metacrilamida que tem a presença do grupo funcional amida e, após hidrólise, a geração de unidade de ácido metacrílico com presença do grupo funcional de ácido carboxílico, ambos os grupos quando combinados possuem uma elevada capacidade de adsorção de cátions. Paralelamente foi aperfeiçoado um sistema de remoção de cátions de solução aquosa usando polímeros confinados em membranas de diálise. A influência da massa molar média, do grau de hidrólise e da presença do grupo funcional de ácido carboxílico foi estudada. Por fim, foi realizado um estudo da capacidade máxima de remoção de Cu(II), em que os parâmetros temperatura, pH da solução, velocidade e tempo de agitação foram fixados. A capacidade máxima de remoção dos íons de Cu(II) variou entre 1,55-1,71 mmol/g para os copolímeros sintetizados e hidrolisados em laboratório, para o copolímero comercial obteve-se um valor de 2,17 mmol/g, e para o copolímero sintetizado diretamente por PRL a partir dos monômeros metacrilamida e ácido metacrílico a capacidade de máxima de captação foi de 3,87 mmol/g , a partir dos resultados foi possível observar uma relação positiva entre a massa molar média das cadeias e a capacidade de ligação aos cátions metálicos. Foi comprovado também que a presença do ácido metacrílico na cadeia polimérica é fundamental para o aumento da capacidade de ligação do cobre. A partir desses estudos foi possível concluir que os polímeros sintetizados e imobilizados em sacos de diálise são eficientes na remoção de íons de Cu(II), Cd(II) e Pb(II) de soluções aquosas, sendo que o estudo da capacidade de remoção dos outros dois cátions Cd (II) e Pb (II) são perspectivas futuras para estudo. No trabalho, destaca-se, além da eficiência, a praticidade do uso do método desenvolvido. / The water pollution by heavy metals is a worldwide problem, but particularly important in countries with intensive mining activities, such as Brazil. Contaminants, especially those known as heavy metals, such as cadmium, lead and others, may have very high toxicity. For this reason, industrial effluents, when not properly treated, are still a big source of contamination of the ecosystem we live in. In order to deal with this current situation, it is necessary to improve metallic cation removal techniques from water what may have a positive impact on Public Health and other areas. Therefore, as a feasible and alternative solution to current metal removal techniques, the present project proposes the production and study of polymeric materials based on partially hidrolised polymethacrylamide with different characteristic for the capture of heavy metals in aqueous solutions. Free radical polymerization techniques were used to synthesize the polymers followed by hydrolysis for the copolymers generation, in order to improve the removal capacity. The amide functional group and, after hydrolysis, the carboxylic group when combined have a high cation adsorption capacity. At the same time, a cation removal system that uses polymers entrapped in a dialysis membrane was improved. The influence of the average molar mass, degree of hydrolysis and the presence of the carboxylic acid functional group was studied. Finally, a study of the maximum Cu (II) removal capacity was carried out, in which the parameters of temperature, solution pH, speed and agitation time were fixed. The maximum removal capacity of Cu (II) ions ranged from 1.55-1.71 mmol/g for the copolymers synthesized and hydrolyzed in the laboratory, the commercial copolymer yielded a value of 2.17 mmol/g, and for the copolymer directly synthesized by PRL from the methacrylamide and methacrylic acid monomers the maximum capacity was 3.87 mmol/g. From the results it was possible to observe a positive relation between the average molar mass of the chains and the ability to connect to the metal cations. It has also been proven that the presence of methacrylic acid in the polymer chain is fundamental for increasing the copper bonding capacity. From these studies it was possible to conclude that both polymers synthesized and immobilized in dialysis bags are efficient in the removal of Cu (II), Cd (II) and Pb (II) ions from aqueous solutions, and the study of the ability to remove the other two cations Cd (II) and Pb (II) are perspectives to future studies. In the work, it is highlighted, besides the efficiency, the convenience of the developed method.

PEIXOTO, Francisca Socorro. Análise da relação espaço-temporal do uso e ocupação do solo com a qualidade da água na Bacia do Açude Acarape do Meio. 2014. 119 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza-CE, 2014. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-06-29T14:46:56Z No. of bitstreams: 1 2014_dis_fspeixoto.pdf: 4410366 bytes, checksum: f92e27f707b76659c61d0ed733adc001 (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-06-29T14:54:53Z (GMT) No. of bitstreams: 1 2014_dis_fspeixoto.pdf: 4410366 bytes, checksum: f92e27f707b76659c61d0ed733adc001 (MD5) / Made available in DSpace on 2016-06-29T14:54:53Z (GMT). No. of bitstreams: 1 2014_dis_fspeixoto.pdf: 4410366 bytes, checksum: f92e27f707b76659c61d0ed733adc001 (MD5) Previous issue date: 2014 / urban areas, the first one is located close to the town of Pacoti and the second is close to Palmácia. The section that receives the largest loads of organic matter is the Canada section, there the maximum value was 1,154.12 kg-1 day. With respect to maps of land use, it was observed that changes occurred in the six evaluated classes, especially with regard to disturbed vegetation and agricultural crops. A significant decrease in the undisturbed vegetation was also observed. / A contaminação dos corpos d’água pela ação antrópica está se tornando cada vez mais frequente e com essa ação as águas estão cada vez mais vulneráveis a degradação. Levando em consideração esses aspectos, o presente trabalho tem como objetivo analisar a relação espaço-temporal do uso e ocupação do solo com a qualidade da água na bacia hidrográfica do Açude Acarape do Meio, no Estado do Ceará, a partir de monitoramento da qualidade das águas no próprio açude e em oito seções fluviais situadas em sua bacia contribuinte. Para a realização deste trabalho foi avaliada a Bacia Hidrográfica do Açude Acarape do Meio, a qual tem aproximadamente 215 Km². Foram utilizados oito anos de dados de qualidade de água do reservatório fornecidos pela Companhia de Gestão dos Recursos Hídricos – COGERH. para este processo foi utilizada estatística multivariada através de duas técnicas, análise de componentes principais e análise de agrupamento. Além desses dados foram realizadas análises laboratoriais das oito seções fluviais de monitoramento que alimentam o referido reservatório, no período de março a junho de 2014, e confeccionado um mapa de uso e ocupação do solo através de imagens de satélite do ano de 2004 (Landsat-5) e de 2013 (Landsat-8). Os resultados da qualidade da água do açude se mostraram bastante variáveis e preocupantes. Para a consolidação desses dados foram formadas quatro componentes principais necessárias para explicar 83% da variabilidade total dos dados. As componentes mais significativas na explicabilidade da qualidade da água no reservatório foram: cálcio, potássio, nitrogênio total, clorofila-a. A segunda técnica avaliada mostrou que a qualidade da água foi separada em quatro grupos, sendo que o grupo um ficou representado pelos dados dos anos de 2004, 2005 e 2006, levando a crer que a qualidade da água nesses anos estaria com características semelhantes. O segundo grupo foi formado somente pelos meses de setembro e outubro de 2012, os quais tiveram uma intensificação dos valores das variáveis analisadas, o que pode ser atribuído ao período de estiagem e que também o referido ano não teve uma quadra invernosa que pudesse contribuir para a o aumento do volume do reservatório e com isso a água ficou mais concentrada e consequentemente os valores dos parâmetros analisados tiveram um “salto”. O grupo três foi formado pelos anos de 2006, 2007, 2008 e 2010. O último grupo ficou apenas com outubro de 2004, isolando-se dos demais. As análises realizadas nas oito seções de monitoramento mostram-se também bastante variáveis em todas as campanhas. Dentre os poluentes mais preocupantes estão os relacionados ao fósforo e à matéria orgânica. As seções de monitoramento que receberam maiores concentrações de nutrientes são a seção Pacoti e a Canabrava, localizadas bem próximas a zonas urbanas, a primeira localizada próxima à cidade de Pacoti e a segunda próxima a Palmácia. A seção que recebe maior carga de poluentes de material orgânico é a seção Canadá, obtendo valor máximo de 1154,12 Kg.dia-1. Com relação aos mapas de uso e ocupação do solo, foi possível observar que houve modificações nas seis classes avaliadas, principalmente no tocante a vegetação antropizada e cultivos agrícolas. Na vegetação nativa também se apresentou um decréscimo significativo.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / The contamination of water bodies by human activities is increasing and with this action the waters are more vulnerable to degradability. Then, the main goal of this work is to analyze the spatial-temporal relationship between land use and water quality in the watershed of the Acarape do Meio Reservoir, located in State of CearÃ, Brazil. Water quality was monitored in the Acarape do Meio Reservoir and in eight river sections located at its tributaries. The Acarape do Meio Reservoir has catchment area of about 215 kmÂ. Water quality data sampled during eight years and provided by the Water Resources Management Company (COGERH) were used in this work. Multivariate techniques were used: principal component analysis and cluster analysis. Laboratory analyzes were performed in water sampled in eight river sections that contribute to this reservoir from March/2014 to June/2014. A land use map was made from satellite images: Landsat-5 image of 2004 and Landsat-8 image of 2013. The results showed that the water quality of the Acarape do Meio Reservoir is quite variable. To consolidate these data four principal components were formed to explain 83% of the total variability of the data. Calcium, potassium, total nitrogen and chlorophyll-a were the parameters that present highest explicability. The other technic showed that the water quality was separated into four groups, with group one being represented by the years 2004, 2005 and 2006. This shows that the water quality in those years presented similar characteristics, as they are quite distinct from the others. The second group was formed only by the months of September and October 2012, due to an intensification of the values of the variables, which can be attributed to the dry season and also a precipitation below the average in that year insufficient to increasing the storage in the reservoir and thus the water became more concentrated. The third group was formed by the years 2006, 2007, 2008 and 2010. The last group isolated the month of October 2004. The analysis made in the eight monitoring river sections also show quite high variability in all samples. Phosphorus and organic matter are the most worrisome pollutants. The monitoring section that receives the highest concentrations of nutrients is Pacoti and Canabrava. Both are very close to urban areas, the first one is located close to the town of Pacoti and the second is close to PalmÃcia. The section that receives the largest loads of organic matter is the Canada section, there the maximum value was 1,154.12 kg-1 day. With respect to maps of land use, it was observed that changes occurred in the six evaluated classes, especially with regard to disturbed vegetation and agricultural crops. A significant decrease in the undisturbed vegetation was also observed. / A contaminaÃÃo dos corpos dâÃgua pela aÃÃo antrÃpica està se tornando cada vez mais frequente e com essa aÃÃo as Ãguas estÃo cada vez mais vulnerÃveis a degradaÃÃo. Levando em consideraÃÃo esses aspectos, o presente trabalho tem como objetivo analisar a relaÃÃo espaÃo-temporal do uso e ocupaÃÃo do solo com a qualidade da Ãgua na bacia hidrogrÃfica do AÃude Acarape do Meio, no Estado do CearÃ, a partir de monitoramento da qualidade das Ãguas no prÃprio aÃude e em oito seÃÃes fluviais situadas em sua bacia contribuinte. Para a realizaÃÃo deste trabalho foi avaliada a Bacia HidrogrÃfica do AÃude Acarape do Meio, a qual tem aproximadamente 215 KmÂ. Foram utilizados oito anos de dados de qualidade de Ãgua do reservatÃrio fornecidos pela Companhia de GestÃo dos Recursos HÃdricos â COGERH. para este processo foi utilizada estatÃstica multivariada atravÃs de duas tÃcnicas, anÃlise de componentes principais e anÃlise de agrupamento. AlÃm desses dados foram realizadas anÃlises laboratoriais das oito seÃÃes fluviais de monitoramento que alimentam o referido reservatÃrio, no perÃodo de marÃo a junho de 2014, e confeccionado um mapa de uso e ocupaÃÃo do solo atravÃs de imagens de satÃlite do ano de 2004 (Landsat-5) e de 2013 (Landsat-8). Os resultados da qualidade da Ãgua do aÃude se mostraram bastante variÃveis e preocupantes. Para a consolidaÃÃo desses dados foram formadas quatro componentes principais necessÃrias para explicar 83% da variabilidade total dos dados. As componentes mais significativas na explicabilidade da qualidade da Ãgua no reservatÃrio foram: cÃlcio, potÃssio, nitrogÃnio total, clorofila-a. A segunda tÃcnica avaliada mostrou que a qualidade da Ãgua foi separada em quatro grupos, sendo que o grupo um ficou representado pelos dados dos anos de 2004, 2005 e 2006, levando a crer que a qualidade da Ãgua nesses anos estaria com caracterÃsticas semelhantes. O segundo grupo foi formado somente pelos meses de setembro e outubro de 2012, os quais tiveram uma intensificaÃÃo dos valores das variÃveis analisadas, o que pode ser atribuÃdo ao perÃodo de estiagem e que tambÃm o referido ano nÃo teve uma quadra invernosa que pudesse contribuir para a o aumento do volume do reservatÃrio e com isso a Ãgua ficou mais concentrada e consequentemente os valores dos parÃmetros analisados tiveram um âsaltoâ. O grupo trÃs foi formado pelos anos de 2006, 2007, 2008 e 2010. O Ãltimo grupo ficou apenas com outubro de 2004, isolando-se dos demais. As anÃlises realizadas nas oito seÃÃes de monitoramento mostram-se tambÃm bastante variÃveis em todas as campanhas. Dentre os poluentes mais preocupantes estÃo os relacionados ao fÃsforo e à matÃria orgÃnica. As seÃÃes de monitoramento que receberam maiores concentraÃÃes de nutrientes sÃo a seÃÃo Pacoti e a Canabrava, localizadas bem prÃximas a zonas urbanas, a primeira localizada prÃxima à cidade de Pacoti e a segunda prÃxima a PalmÃcia. A seÃÃo que recebe maior carga de poluentes de material orgÃnico à a seÃÃo CanadÃ, obtendo valor mÃximo de 1154,12 Kg.dia-1. Com relaÃÃo aos mapas de uso e ocupaÃÃo do solo, foi possÃvel observar que houve modificaÃÃes nas seis classes avaliadas, principalmente no tocante a vegetaÃÃo antropizada e cultivos agrÃcolas. Na vegetaÃÃo nativa tambÃm se apresentou um decrÃscimo significativo.

A poluição de corpos d´água por metais pesados é um problema mundial, mas particularmente importante em países que apresentam atividades intensas de mineração, como o Brasil. Os contaminantes, de maneira especial aqueles conhecidos como metais pesados, podem apresentar toxicidade altíssima, como é o caso do cádmio, chumbo e outros. Por esse motivo, os efluentes industriais, quando não devidamente tratados, ainda são uma grande fonte de contaminação do ecossistema que vivemos. Diante dessa atual situação, esforços para o aprimoramento de técnicas de remoção de cátions de metais pesados da água são necessárias e podem ter impacto positivo na Saúde Pública e em outras áreas. Portanto, como solução viável e alternativa para o que já se é feito, o presente projeto propõe a produção e estudo do uso de materiais poliméricos com propriedades distintas para captação de metais pesados de soluções aquosas. Para a síntese dos polímeros foram usadas técnicas de polimerização via radical livre, e posterior hidrólise para geração de copolímeros, com o intuito de aperfeiçoar a capacidade de remoção. Os polímeros tiveram como base a metacrilamida que tem a presença do grupo funcional amida e, após hidrólise, a geração de unidade de ácido metacrílico com presença do grupo funcional de ácido carboxílico, ambos os grupos quando combinados possuem uma elevada capacidade de adsorção de cátions. Paralelamente foi aperfeiçoado um sistema de remoção de cátions de solução aquosa usando polímeros confinados em membranas de diálise. A influência da massa molar média, do grau de hidrólise e da presença do grupo funcional de ácido carboxílico foi estudada. Por fim, foi realizado um estudo da capacidade máxima de remoção de Cu(II), em que os parâmetros temperatura, pH da solução, velocidade e tempo de agitação foram fixados. A capacidade máxima de remoção dos íons de Cu(II) variou entre 1,55-1,71 mmol/g para os copolímeros sintetizados e hidrolisados em laboratório, para o copolímero comercial obteve-se um valor de 2,17 mmol/g, e para o copolímero sintetizado diretamente por PRL a partir dos monômeros metacrilamida e ácido metacrílico a capacidade de máxima de captação foi de 3,87 mmol/g , a partir dos resultados foi possível observar uma relação positiva entre a massa molar média das cadeias e a capacidade de ligação aos cátions metálicos. Foi comprovado também que a presença do ácido metacrílico na cadeia polimérica é fundamental para o aumento da capacidade de ligação do cobre. A partir desses estudos foi possível concluir que os polímeros sintetizados e imobilizados em sacos de diálise são eficientes na remoção de íons de Cu(II), Cd(II) e Pb(II) de soluções aquosas, sendo que o estudo da capacidade de remoção dos outros dois cátions Cd (II) e Pb (II) são perspectivas futuras para estudo. No trabalho, destaca-se, além da eficiência, a praticidade do uso do método desenvolvido. / The water pollution by heavy metals is a worldwide problem, but particularly important in countries with intensive mining activities, such as Brazil. Contaminants, especially those known as heavy metals, such as cadmium, lead and others, may have very high toxicity. For this reason, industrial effluents, when not properly treated, are still a big source of contamination of the ecosystem we live in. In order to deal with this current situation, it is necessary to improve metallic cation removal techniques from water what may have a positive impact on Public Health and other areas. Therefore, as a feasible and alternative solution to current metal removal techniques, the present project proposes the production and study of polymeric materials based on partially hidrolised polymethacrylamide with different characteristic for the capture of heavy metals in aqueous solutions. Free radical polymerization techniques were used to synthesize the polymers followed by hydrolysis for the copolymers generation, in order to improve the removal capacity. The amide functional group and, after hydrolysis, the carboxylic group when combined have a high cation adsorption capacity. At the same time, a cation removal system that uses polymers entrapped in a dialysis membrane was improved. The influence of the average molar mass, degree of hydrolysis and the presence of the carboxylic acid functional group was studied. Finally, a study of the maximum Cu (II) removal capacity was carried out, in which the parameters of temperature, solution pH, speed and agitation time were fixed. The maximum removal capacity of Cu (II) ions ranged from 1.55-1.71 mmol/g for the copolymers synthesized and hydrolyzed in the laboratory, the commercial copolymer yielded a value of 2.17 mmol/g, and for the copolymer directly synthesized by PRL from the methacrylamide and methacrylic acid monomers the maximum capacity was 3.87 mmol/g. From the results it was possible to observe a positive relation between the average molar mass of the chains and the ability to connect to the metal cations. It has also been proven that the presence of methacrylic acid in the polymer chain is fundamental for increasing the copper bonding capacity. From these studies it was possible to conclude that both polymers synthesized and immobilized in dialysis bags are efficient in the removal of Cu (II), Cd (II) and Pb (II) ions from aqueous solutions, and the study of the ability to remove the other two cations Cd (II) and Pb (II) are perspectives to future studies. In the work, it is highlighted, besides the efficiency, the convenience of the developed method.

High anthropogenic modification like infrastructural development, drainage, eutrophication, dumping garbage, is a threat to biodiversity of smaller water bodies in agricultural landscapes. However, smaller water bodies have historically been constructed for drainage, waste treatment and other purposes. Further, new small water bodies are now being constructed in agricultural areas in Sweden, mainly to remove nutrients and to improve landscape biodiversity. This creates two different age classes (old and new) of smaller water body habitats. I sampled aquatic insects in 27 smaller water bodies of varying types and ages in Halmstad region and related insect biodiversity, species richness, composition structure to environmental variables. I partitioned the region into two locations (Northern and Southern) for easy data comparison and due to difference in topography. The data was analysed using a Canonical Correspondence (CCA) and regression analysis. The CCA results show a difference in the species composition between old and new sites. The most important variables in explaining species assemblage structure was age of the aquatic water bodies. The species richness decreased with increase in nutrient concentration (total phosphorus) according to regression analysis. Species composition and diversity were related to Vegetation and tree cover in and around the water body. The results of my study shows that the older the water bodies the better for specific species like Aeshna cyanea and the new water bodies tolerate more specimens. My results suggest that, as there is need to facilitate plant growing, protecting vegetation and trees to better mimic natural conditions of water bodies, creating new water bodies while protecting aged water bodies is important for conservation of biodiversity.

Triops cancriformis (Crustacea: Notostraca) occurs in ephemeral habitats like rain pools or floodplain pools distributed over a large geographical range. The named habitats are disturbed by human impacts and, consequently, T. cancriformis is endangered throughout its distribution range. In the present thesis the populated habitats and threats are characterised and further morphological and genetic variations detected among and within European populations are reported. On the basis of recent investigations it is shown that T. cancriformis subspecies separation is hampered by an individual variability which points to the necessity of species revision. The analysis of mitochondrial gene sequence data suggests that the species has colonised most of Europe very recently. The advantage of a complex reproductive strategy in T. cancriformis in this process is discussed. The population structure resolved with nuclear DNA markers highlights that there is low allelic diversity among and within populations compared to other Branchiopoda (Daphnia). By means of the present study it can be shown that habitat conservation is most important to protect T. cancriformis.