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Recent carbonate sediments from Jamaican north coast fringing reefs display variation in constituent composition, texture, and mineralogy related to their location on the reef. Samples were collected along lines which traversed the back reef and fore reef (0.5m to 70m). The sediment is dominated by highly comminuted coral fragments, plates of the calcareous green alga, Halimeda, coralline algae, and the encrusting Foraminifera, Homotrema rubrum, with lesser amounts of other taxonomic groups (Foraminifera; molluscs; echinoderms). Relative abundances of these biotic components vary between sites. Q-mode cluster analysis indicates that constituent composition can be used to delineate the different reef zones which have been described from analyses of the macrofauna. For most sediment, grain-size frequency distributions indicate that greater than 90% (by weight) of the sample is contained in the interval of 0.125mm to 2.000mm. Mean grain size approaches 0.5mm for most sites with little depth related variation. Sorting, however, becomes progressively poorer from the shallow (5m) fore reef terrace to the upper deep fore reef (70m). X-ray diffraction and insoluble residue analyses indicate that total CaC03 in these sediments is generally greater than 95% by weight. Aragonite is the most abundant carbonate phase, followed by high-Mg calcite , and low-Mg cal cite. Amorphous siliceous sponge spicules and organic matter comprise the remaining non-carbonate fraction of these sands. Significant differences in the proportions of aragonite and high-Mg calcite between fore reef terrace sediments and sediments from other reef zones results from the contribution of high-Mg calcite to fore reef terrace sediments by coralline algae, Foraminifera (principally Homotrema rubrum) and echinoderms, which are relatively less abundant sediment constituents elsewhere on the reef. The 120,000y.b.p.(Sangamon) Falmouth Formation along the north coast of Jamaica displays variability in sedimentological and faunal components analogous to that of back reef and shallow fore reef environments of the modern Jamaican fringing reef system. X-ray analysis of the mineralogy of Falmouth limestones reveals that surface exposures of fore reef grainstones exhibit greater diagenetic alteration than surface exposures of back reef packstones. This indicates variability in diagenetic processes most likely related to original sediment textural characteristics.

This study investigates the downstream controls of alluvial sediment composition and river channel adjustment in the Llano River watershed, Central Texas, USA. The Llano River watershed is characterized by a highly variable, flood-prone flow regime and a complex lithology of Cretaceous carbonate rock, Paleozoic sedimentary rock, and Precambrian igneous and metamorphic rock. Sedimentary variables for this study include particle size, sorting, carbonate content, and magnetic susceptibility. Channel adjustment includes the planform dimension and cross-sectional dimensions of bankfull- and macro-channels. Nineteen sites along the Llano River and selected tributaries were visited to measure cross-sectional channel geometry and sample bed, bank, and overbank sediment. Laboratory analyses of sediment and hydraulic analyses of cross sections were accompanied by analyses of partial-duration flood frequency, flow resistance, hydrography, digital elevation models, and statistical correlation. Findings include: (1) channel-bed material reduces in size with downstream distance, despite increasing valley confinement and bedrock exposure; (2) the downstream decrease in particle size is more evident for channel-bar deposits than for low-flow-channel (thalweg) deposits; (3) an abrupt gravel-to-sand transition occurs about 20 kilometers downstream of the Paleozoic-Precambrian contact; (4) an abrupt coarse- to fine-gravel transition occurs between 75 and 90 kilometers downstream the North Llano and South Llano Rivers; (5) channel-bank material increases downstream, contrasting with decreases in bed material; (6) carbonate content and magnetic susceptibility of alluvial sediment are inversely related, with carbonate content peaking near Junction; (7) four general categories to classify reaches of the North Llano, South Llano, and Llano Rivers are based on hydrology, planform morphology, lithology, and valley confinement; (8) mean depth increasingly compensates for bankfull discharge in a downstream direction; (9) mean depth compensates more than width for macrochannels; and (10) the return periods for bankfull and macro-channels are about 1 to 2 years and greater than 10 years, respectively. The results of this study will contribute to fluvial geomorphic theory of downstream trends in sediment composition and channel adjustment; as well as inform applied efforts related to aquatic biology, flood hazards, infrastructure design, and riparian and water-resource management in the region. / text

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A beach is an accumulation on the shore of unconsolidated sediment and its composition and texture are directly related to the available source of material and the coastal processes that modify the sediments during long periods. Coastal and shallow marine sediments are usually of heterogeneous nature, composed of variable mixtures of siliciclastic and bioclastic particles. Surface samples collected in the beach face from eighteen stations along south Alagoas coast were analyzed concerning textural and compositional characteristics. Mean grain size and sorting were obtained through dry mechanical sieving, with processing of the samples using the SYSGRAN package. Three hundred grains were identified for each grain size class coarser than 0.125 mm. Compositional analysis was carried out with the identification of 300 grains for each grain size class coarser than 0.125 mm. Grain size distribution ranged from medium sand to very fine sand with predominance of the latter, mostly moderately sorted. Coarser sands were found in Pontal do Peba and in the narrow beaches of Miaí de Cima and Barreiras. The sedimentation in the studied beaches showed predominance of siliciclastic grains, mainly quartz. The highest concentrations of bioclastic grains are near the Ponta do Peba bank and the north of this point the proportion of bioclasts gradually decreases. The main biogenic components are molluscs shells and fragments of red algae and Halimeda. Echinoderms spines and fragments, bryozoans and foraminifera tests also contribute significantly to the beach deposit. The sediment distribution pattern suggests that in addition to the grains originated from the hinterland, the continental shelf constitutes an important sediment source for the beaches. / As praias constituem depósitos de material inconsolidado cuja composição e textura estão diretamente relacionadas com a fonte de material disponível e os processos costeiros que modificam os sedimentos durante longos períodos. Sedimentos marinhos rasos e costeiros são comumente de natureza heterogênea, compostos por misturas variáveis de partículas silicilásticas e bioclasticas. Amostras superficiais coletadas na face de praia de dezoito estações distribuídas ao longo de 36 km de litoral no sul de Alagoas foram analisadas quanto a composição e aspectos texturais. A granulometria e grau de seleção foram obtidos através do peneiramento mecânico a seco, com processamento das amostras no Sistema de Análises Granulométricas (SYSGRAN). Trezentos grãos aleatórios de cada fração ganulométrica superior a 0,125mm foram identificados por meio de lupa binocular. A granulometria oscilou entre areia média e areia muito fina, com predomínio da última, em maioria moderadamente selecionadas. Sedimentos de granulometria mais grossa foram encontrados no Pontal do Peba e nas estreitas praias de Miaí de Cima e Barreiras. A sedimentação nas praias estudadas mostrou predomínio de grãos siliciclásticos, sobretudo quartzo. As maiores concentrações de grãos bioclásticos estão nas proximidades do Pontal do Peba e a norte deste ponto a proporção de bioclastos gradualmente diminui.Os principais componentes biogênicos encontrados foram as conchas de moluscos e fragmentos de algas vermelhas e Halimeda. Espinhos e fragmentos de equinodermos, briozoários e carapaças de foraminíferos também contribuem expressivamente para o depósito praial. O padrão de distribuição dos sedimentos sugere que, além dos grãos oriundos do interior do continente, a plataforma continental constitui uma importante fonte de sedimentos para as praias.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-03-24T16:04:45Z No. of bitstreams: 1 Dissertação - Silvia Lisboa.pdf: 3038622 bytes, checksum: d6fd17f5be7eb5edaafbd1fba3718a41 (MD5) / Made available in DSpace on 2017-03-24T16:04:45Z (GMT). No. of bitstreams: 1 Dissertação - Silvia Lisboa.pdf: 3038622 bytes, checksum: d6fd17f5be7eb5edaafbd1fba3718a41 (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências- Geoquímica Ambiental. Niterói, RJ / Com os danos que vêm sendo causados nos ecossistemas recifais brasileiros e considerando suas altas taxas de endemismo, a conservação da biodiversidade dos mesmos é indispensável e a utilização de indicadores ambientais é importante para o estudo dos fenômenos que afetam os ecossistemas marinhos. É nesse contexto que a assembleia de foraminíferos bentônicos tem sido amplamente utilizada como indicadores da qualidade ambiental de ecossistemas de recifes de coral, uma vez que estes organismos estão entre os principais produtores do sedimento recifal. Desta forma, o objetivo deste trabalho foi avaliar a interação entre os indicadores geoquímicos e a fauna de foraminíferos bentônicos na caracterização ambiental do Recife de Fora, que corresponde a uma área de proteção marinha, porém com intensa visitação turística e exploração de seus recursos. As estações de amostragem foram escolhidas aleatoriamente e totalizaram 59 amostras de sedimento superficial, destinadas às análises de tamanho dos grãos, matéria orgânica, carbonato de cálcio e foraminíferos. A face leste apresentou os maiores teores de areia e de carbonato de cálcio dentre as demais estações, já a face oeste do Recife de Fora apresentou o sedimento composto predominantemente por lama e com maiores concentrações de matéria orgânica. Nesta mesma área foram obtidos os maiores índices de diversidade (Shanon-Wiener) e a maior abundância dos foraminíferos oportunistas Bolivina, Ammonia e Nonion. Sendo assim, a relação entre o tipo de sedimento e a diversidade e a composição da assembleia de foraminíferos observada permite concluir que a fauna analisada exibe padrões de distribuição relacionados principalmente aos parâmetros sedimentológicos, associados à presença de corpos recifais / With the damages that have been caused in the brazilian reefs ecosystems and considering their high endemism, the conservation of biodiversity therefore is indispensable and the use of bioindicators are important for understanding the phenomena that affects marine ecosystems. In this context, the foraminiferal assemblages have been widespread used as environmental quality indicators of coral reefs, since these organisms are among the main producers of reef sediments. The aim of this work was to evaluate the interaction between geochemical parameters and benthic foraminifera assemblages to assess the environmental quality of Recife de Fora, which corresponds to a marine protected area subject to tourism and exploitation of its resources. For this purpose, 59 random stations were chosen for surface sediment sampling and analyses of particle size, organic matter content, calcium carbonate and foraminifera. The seaward side of the reef had the highest proportions of sand and calcium carbonate among all stations and the landward exhibited the sediments, mainly composed of mud and higher concentrations of organic matter. In the latter area the highest diversity indexes (Shanon-Wiener) were found with a greater abundance of the stress-tolerant foraminifera Bolivina, Ammonia and Nonion. As such, a close relationship among the sediment type with the diversity and the composition of foraminifera assemblage indicating that the distribution pattern of the analysed fauna is directly related to sedimentary parameters associated with the presence of coral reefs and hydrodynamic conditions operating in the area

The discovery of antibiotics is considered as one of the most significant scientific achievements of the 20th century – lives of millions of people and animals have been saved. Thenceforth, substantial amounts of administered antibiotics and their metabo-lites have been excreted into waste stream via urine and faeces. In this dissertation, primary focus is the qualitative balance of 14 antibiotics and one metabolite in urban water management and in urban waters, respectively. In particular, antibiotics pre-scribed to human beings are drained in the urban sewer system and finally enter the environment: (i) Continuously via the effluent of the wastewater treatment plant after a partially effective removal or degradation or (ii) Intermittent via combined sewer overflow structures due to capacity limitations of the urban drainage system. The fate and the potential effects and risks of these substances on ecosystems and hu-man health are of major concern – their direct toxic effect to all trophic levels as well as the global spread of antibiotic resistance genes are challenging. Hence, an assessment of microbial community activity due to antibiotic exposure is presented. In particular, systematic work has been carried out to study the presence and character-istics of 14 antibiotics in urban waters. In detail, investigations were conducted to gain scientific knowledge with respect to adsorption, desorption, abiotic, biotic and photolyt-ic degradation as well as activity-inhibition of microorganism communities in sewage and of natural freshwater biofilm communities, respectively, due to inevitable urban drainage overflows. In order to provide information to assist potential management strategies, which miti-gate surface water pollution and minimize the adverse impacts of antibiotics on activity of microorganism communities, the following specific topics were addressed: ⑴ The occurrence of 14 antibiotics and one metabolite were determined in sewag-es at three sampling sites in the city of Dresden, Germany. ⑵ The adsorption affinities of 14 antibiotics and one metabolite to size dependent sewer sediments were determined in experimental investigations, three sam-pling campaigns and subsequently an antibiotic-specific adsorption coefficient, normalized to organic content, was quantified. ⑶ The desorption affinity and -dynamics of 14 antibiotics and one metabolite were quantified in size dependent sewer sediments in experimental investigation and with statistical analysis. ⑷ The abiotic, biotic and photolytic degradation affinity of 14 antibiotics and one metabolite were quantified based on batch experiments with three different sewages at 7°C and 22°C, with artificial irradiation and different dilution ratios of the sewage at 30°C and subsequently a model framework decrypted ranges of abiotic, biotic and photolytic degradation coefficients. ⑸ The occurrence of three antibiotics, namely ciprofloxacin, clarithromycin and doxycycline was determined in sewage sampled during dry weather conditions in a small catchment of Dresden, which spills intermittently combined sewage (a mixture of sewage and storm water) to an adjacent brook in the case of capacity limitations of the urban drainage system during periods of intense rainfall and subsequently the three antibiotics were determined in the adjacent brook water. ⑹ Then, the activity-inhibition of microorganism community in sewage of this small catchment was quantified due to an exposition with three different antibiotics and three different antibiotic concentrations. ⑺ Last but not least, the activity-inhibition of natural freshwater biofilm communities in the adjacent brook was quantified via exposure to three antibiotics, which were individually dosed in three different concentrations, and also in mixture. ⑻ Finally, a two-dimensional hierarchical cluster analysis with dendrogram and heat map based on before mentioned activity inhibition of natural freshwater biofilm communities were conducted to identify hot spots of antibiotic tolerant and resistant bacterial subpopulations due to inevitable urban drainage system overflows.:List of Figures IV List of Tables VIII Symbols and Abbreviations XII List of Publications on the Ph.D. topic XIX 1 General Introduction 2 1.1 Background 2 1.2 Aims and Objectives 3 1.3 Innovation and Contribution to the Knowledge 4 1.4 Outline of this Thesis 4 1.5 References 6 2 Adsorption and Desorption Affinity of 14 Antibiotics and One Metabolite for particulate components in urban drainage systems 10 2.1 Introduction 11 2.2 Materials and Methods 12 2.2.1 Study area 12 2.2.2 Sewer sediment and sewage sample collection 12 2.2.3 Sediment fractionation 13 2.2.4 Antibiotic determination in sewage and sediment 13 2.3 Results and Discussion 18 2.3.1 Antibiotics in composite sewage samples 18 2.3.2 Antibiotics adsorbed to sewer sediments 19 2.3.3 Organic-bound antibiotic load as a linear function of liquid concentration 20 2.3.4 Adsorption dynamics and adsorption coefficient determined by bath experiments 20 2.3.5 Mineral composition of sewer sediment SED#1B 23 2.3.6 Initial characteristics of sediment SED#1B 23 2.3.7 Desorption dynamics and desorption coefficient of SED#1B 24 2.4 Conclusions 25 2.5 References 26 3 Abiotic, Biotic and Photolytic Degradation Coefficients of 14 Antibiotics and One Metabolite 32 3.1 Introduction 34 3.2 Materials and Methods 35 3.2.1 Study area and sample collection 35 3.2.2 Experimental set up 35 3.2.3 Modelling framework 38 3.2.4 Procedure of model calibration 40 3.3 Results and Discussion 43 3.3.1 Primary metabolic parameter 43 3.3.2 Secondary metabolic parameter 44 3.4 Conclusions 50 3.5 References 50 4 Activity-Inhibition of Microorganisms due to an Exposition with different Antibiotics and Concentrations 56 4.1 Assessing Antibiotic Resistance of Microorganisms in Sanitary Sewage 56 4.1.1 Introduction 57 4.1.2 Material and Methods 58 4.1.2.1 Sampling Site and Antibiotic Agents 58 4.1.2.2 Analyzing Antibiotics 60 4.1.2.3 Respiration Rate 60 4.1.3 Results and Discussion 60 4.1.3.1 Concentration Range of Antibiotics and Typical Sewage Parameters 60 4.1.3.2 Oxygen Uptake Rate 62 4.1.4 Summary and Conclusions 63 4.1.5 References 64 4.2 Hot Spots of Antibiotic Tolerant and Resistant Bacterial Subpopulations in Natural Freshwater Biofilm Communities due to Inevitable Urban Drainage System Overflows 66 4.2.1 Introduction 68 4.2.2 Material and Methods 69 4.2.3 Results and Discussion 72 4.2.4 Conclusions 76 4.2.5 References 76 5 Summery and General Coclusions 82 5.1 Adsorption and Desorption Affinity 82 5.2 Abiotic, Biotic and Photolytic Degradation 83 5.3 Activity-Inhibition of Microorganism Communities due to Antibiotic Exposure 84 5.4 Enhancement of the Stockholm County Council (2014) assessment of antibiotics 84 5.5 References 87 6 Proposed Directions of Future Research 90 7 Appendixes 94 7.1 Chapters 94 7.2 Figures 95 7.3 Tables 115 7.4 References 139