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La presente tesis "estudio de los efectos sobre el medio litoral derivados de la implantación de saneamientos integrales en la costa Cantábrica" pretende evaluar la validez de los diseños ambientales de estos saneamientos integrales como instrumentos predictivos aplicables a la gestión de la calidad de los sistemas acuáticos litorales mediante la realización de estudios dirigidos a analizar la afección que originan los vertidos de aguas tratadas a través del emisario submarino sobre el estado de las aguas costeras, sobre la calidad de los fondos sedimentarios y sobre las comunidades bentónicas establecidas; así como, mediante el análisis de la evolución de la calidad de las masas de agua estuarinas afectadas por los vertidos de tormenta. Los resultados obtenidos han servido para proponer una serie de indicaciones para el diseño de los programas de control operativo planteados en la DMA, a aplicar en las masas de agua afectadas por este tipo de vertidos. / This PhD thesis titled "Effects of coastal sanitations on Cantabrian littoral ecosystems (Bay of Biscay)" was carried out to evaluate the applicability of the environmental design of the sewer systems constructed in the north of Spain to the management of the aquatic ecosystems. This work has analysed the effects caused by the treated effluents discharged by the submarine outfall on the water and sediment quality and on the structure and composition of the hard-bottom benthic communities dwelling the outfall surroundings. On the other hand this study has analysed the recovery of the estuarine ecosystem (water, bacteriology, sediments and benthic organisms) directly affected in the past by the urban effluents and nowadays affected by storm discharges. Results obtained in both surveys have contributed to propose a guidance for the design of the Operative control of the water masses established in the EU Water Framework Directive in the north of Spain.

Optical parameters measured via absorption spectroscopy and high-resolution fluorescence spectroscopy were used to characterize dissolved organic matter (DOM) in the springshed of Kings Bay, a spring-fed estuary located on Florida's Springs Coast. Over the past 40 years, springs supplying groundwater to Kings Bay have shown an increase in nitrate concentration. The overall goal of this project was to fingerprint wells and spring sites with elevated nitrogen concentrations using CDOM optical properties and establish relationships between nutrient and optical parameters. Samples were obtained from various sites: springs, Kings Bay surface (KBS), wells, coastal waters in and at the mouth of Crystal River (Coast) and lakes and rivers (LNR), during dry and wet seasons. The relationships between the environmental parameters and traditional optical parameters which provide insight into source characteristics were analyzed. Excitation emission matrix spectroscopy (EEMS) provided information about the concentration and chemical nature of organic matter in the study area. CDOM optical properties combined with salinity clearly separated the sources of fixed nitrogen in the Bay. Northern springs with elevated dissolved inorganic nitrogen (DIN) concentration had lower salinities and showed a presence of protein peaks. CDOM concentration was negatively correlated with total nitrogen (TN) and DIN, which suggests that these are subjected to anthropogenic influences. Humic peaks dominated the composition of the southern springs. CDOM concentrations were much higher than in the northern springs and there was a positive correlation between CDOM and both TN and DIN. These findings suggest that the fixed nitrogen in the southern springs is naturally occurring organic matter and the low concentrations may partially be a result of subsurface mixing of saltwater and freshwater in the aquifer. Thus, hypothesis testing showed that there was a significant difference between northern and southern springs Hypothesis testing also showed that there is a significant and unexpected positive relationship between CDOM and salinity studying Kings Bay, which is due to the low CDOM concentration in the springs discharging fresh water. This unique dataset also determined that the intercept of the mixing line was significantly different form zero. This indicates that CDOM is present and detectable at very low concentrations. Parallel Factor Analysis (PARAFAC) was used to evaluate CDOM composition from excitation emission matrix spectra (EEMs) and five components were identified: two humic, two marine humic, and one protein-like. The marine-like components, peak M, were produced in the marine environment and in meteoric groundwater. The study found a unique groundwater marker for coastal regions. Northern Kings Bay sites were characterized by a protein-like component, which has been associated with wastewater. Additional optical and environmental parameters were used in discriminate analysis, which successfully identified the CDOM markers for both natural and anthropogenic sources of nutrients in the environment. It is vital to improve the analysis of water, nutrients, and carbon from groundwater discharge into the coastal zone. Elevated DIN concentrations in groundwater are a widespread problem in Florida and over the past 30 years many spring waters have shown an increase in DIN concentrations. Nutrient discharge into delicate coastal areas can lead to ecological concerns. Investigating CDOM and nutrient distribution together can be a beneficial tool that can help differentiate sources from riverine/lacustrine, estuarine, marine, groundwater, and sewage impacted categories.

Les sédiments sont des sites importants d’élimination d’azote (N) puisqu’ils possèdent des gradients d’oxydoréduction leur conférant les conditions idéales pour les réactions microbiennes de transformation de N. L’eutrophisation des régions côtières peut altérer ces gradients, par des changements dans la concentration d’oxygène (O2) de l’eau interstitielle, et modifier l’importance relative des processus transformant le N. Afin de mieux comprendre comment l’O2 pourrait influencer les transformations de N, nous avons mesuré les flux diffusifs de diazote (N2), nitrate (NO3-), oxygène et ammonium (NH4+) dans les sédiments de l’Estuaire Maritime du St-Laurent (EMSL), et nous avons estimé les taux de dénitrification. L’importance du couple nitrification-dénitrification en fonction d’un gradient de concentrations d’O2 dans la zone d’hypoxie de l’EMSL fut aussi évaluée. La concentration des gaz dissous fut mesurée en utilisant une nouvelle approche développée dans cette étude. Les flux diffusifs de N2, O2, NO3- et NH4+ variaient de 5.5 à 8.8, de -37.1 à -84.8, de -4.0 à -5.8 et de 0.6 à 0.8 μmol N m-2 h-1 respectivement. Les concentrations de N2 et NO3- dans l’eau porale et les flux de NO3- et de N2 des sédiments, suggèrent que la diffusion de NO3- provenant de l’eau à la surface des sédiments ne peut pas expliquer par elle-même la production de N2 observée. En utilisant une approche stoichiométrique, les taux de nitrification potentielle estimés comptent pour 0.01 à 52% du flux total de NO3 nécessaire pour aboutir aux flux de N2 observés et diminuent avec l’augmentation de l’hypoxie. / Sediments display strong redox gradients and represent important sites of various microbially mediated nitrogen (N) transformation pathways resulting in the loss of fixed N. Increased eutrophication of coastal systems will likely impact the overall function of these sediments via changes in the oxygen (O2) concentration in the overlying water, thus influencing the redox gradient and the relative importance of different N processes. To have a better understanding of how O2 could influence N transformations, we measured dinitrogen (N2), nitrate (NO3-), oxygen and ammonium (NH4+) diffusive fluxes in the sediments of the Lower St. Lawrence Estuary (LSLE) and estimated denitrification rates. The importance of the nitrification-denitrification couple as a function of a gradient of hypoxic O2 concentrations was also evaluated. Dissolved gas concentrations were measured using a new approach developed in this study. N2, O2, NO3- and NH4+ diffusive fluxes varied respectively from 5.5 to 8.8, from -37.1 to -84.8, from -4 to -5.8 and from 0.6 to 0.8 μmol N m-2 h-1 among the five stations sampled. N2 and NO3- concentrations in sediment pore water and measured fluxes of NO3- in and N2 out of the sediments suggested that NO3- diffusion from the overlying water alone could not support N2 production. Using a stoichiometric approach, estimated potential nitrification rates varied among sites, from 0.01 to 52% of the total NO3 supply rate. The relative importance of nitrification decreased with increasing hypoxia.

The Isipingo River and Estuary system located in the province of KwaZulu-Natal, although relatively small, has been subjected to the impacts of intense development within the catchment. The catchment is characterized by informal and formal dwellings and intensive industrial activities in the lower catchment and in close proximity to the estuary. Significant modifications to the hydrology of the system has occurred as a result of the diversion of the Umlazi River (which previously merged with the Isipingo River at the estuary mouth), canalization of the lower portion of the Isipingo River flowing through the Prospecton Industrial Area and the development of the Diversion Works system (to regulate flows to the lower Isipingo River), removal of riparian vegetation, encroachment onto the river and estuarine floodplain, and land reclamation through the infilling of wetlands all of which has culminated in a deterioration of the functionality and health of this system. The main aspects of this study focus on water and sediment quality, material flux between the estuary and the sea and the management of the system. The water quality variables covered as part of this dissertation include physical, chemical (nutrients and heavy metals) and microbiological (faecal coliforms) components. The water quality of the river and estuary presents a risk to human health and the concentrations of heavy metals generally exceeded the South African Water Quality Guidelines that prescribes target levels, implying potential negative impacts to aquatic health. The Isipingo system exhibited signs of eutrophication with phosphorus concentrations in excess of the target level to prevent eutrophication. Excessive water hyacinth growth was visible during most of the field surveys. A geochemical assessment of heavy metals in surface sediments of the river and estuary was also undertaken. The results indicate that although the presence of several metals were undetectable at certain river sites, the concentrations of those heavy metals present increased in a longitudinal direction from the river to the estuary. The contamination factor analysis for all metals indicated low contamination except for selenium. The riverine sites yielded moderate enrichment by some heavy metals in both seasons. The degree of contamination for each site with the exclusion of selenium was low. The inclusion of selenium in the assessment raises the estuary to a considerably contaminated status in the wet season. The analysis suggests that the enrichment of the system by selenium is due to an anthropogenic source. The Geo-accumulation Index places the sediment in an overall unpolluted category. The study conducted on the net exchange of heavy metals and nutrients between the Isipingo Estuary and the adjacent marine environment (i.e. Indian Ocean) demonstrates that significant quantities of the suite of heavy metal analysed are exported on an annual basis while copper, nickel and zinc are imported into the estuary. Significant quantities of ammonia and nitrates are exported annually from the Isipingo Estuary while a net annual import of phosphorous is observed. The variation in the quantity and concentration of nutrients exported during the seasons may be attributed to anthropogenic source. The import of nutrients from marine sources can accumulate in the estuary and contribute to eutrophication of the Isipingo Estuary. This study also demonstrated that although the ebb flow has a much longer duration than the flood flow, the flood velocities observed were generally greater than the ebb velocities. The final part of this research identifies other environmental problems experienced in the Isipingo catchment. The following issues are identified as directly or indirectly contributing to stress and deterioration of the water quality of the Isipingo system: reduction in water quantity, poor water quality, moderate enriched sediment, loss of habitat integrity, species diversity and invasive alien vegetation and uncontrolled solid waste. A Water Quality Management Plan including management objectives, strategies and action plans to address the direct and indirect factors influencing the system are proposed. A water quality monitoring program is also proposed for the Isipingo River and Estuary. The adoption and execution of the water quality management plan and monitoring program will assist in the prevention of further degradation of the system and will be a stepping stone toward improvement. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2013.

Made available in DSpace on 2014-12-17T15:54:56Z (GMT). No. of bitstreams: 1 LuizFDPN_DISSERT.pdf: 2209793 bytes, checksum: abf28b0dea288454043f2a92ced47d86 (MD5) Previous issue date: 2011-02-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Environmental issues are becoming increasingly habitual to the media, particularly when calamities are involved. A feature of environmental disasters is that they disclose both environmental crises and the media limitation in reporting them. The research tried to contribute to the subject through the study of press media coverage of a large fish kill along an estuary in the State of Rio Grande do Norte, Brazil, in 2007. Thematic content analysis of newspaper reports identified the predominance of a superficial and denunciative coverage, lacking an educational perspective, and with little contribution to formation of a critical sense in readers. It also has identified the precarious treatment of those scientific concepts that could substantiate the actual causes of mortality of tons of aquatic fauna / A m?dia tem evidenciado de forma crescente a quest?o ambiental, principalmente em situa??es de desastres. Nessas ocasi?es, a imprensa, al?m de expor a degrada??o do meio ambiente, revela suas pr?prias limita??es para abordar o tema. A pesquisa buscou dar uma contribui??o ao assunto, por meio do estudo da cobertura jornal?stica realizada pela m?dia impressa de um evento que envolveu a mortandade de peixes no estu?rio do rio Potengi, em Natal-RN, no ano de 2007. A an?lise de conte?do jornal?stico identificou a predomin?ncia de uma cobertura superficial, denunciativa e com raras abordagens educativas, contribuindo pouco para a forma??o do senso cr?tico dos leitores. Identificou tamb?m o tratamento prec?rio dos conceitos cient?ficos capazes de fundamentar os reais motivos relacionados ? mortandade de toneladas de fauna aqu?tica

Made available in DSpace on 2014-12-17T14:08:43Z (GMT). No. of bitstreams: 1 MariaSMQ_DISSERT_1-36.pdf: 5283210 bytes, checksum: e75f1aa1d6f8e40607338226667f1b0d (MD5) Previous issue date: 2011-02-07 / Estuaries are environments prone to the input of chemical pollutants of various kinds and origins, including polycyclic aromatic hydrocarbons (PAHs). Anthropogenic PAHs may have two possible sources: pyrolytic (with four or more aromatic rings and low degree of alkylation) and petrogenic (with two and three aromatic rings and high degree of alkylation). This study aimed to evaluate the levels, distribution and possible sources of polycyclic aromatic hydrocarbons in the estuary of the Potengi river, Natal, Brazil. Samples of bottom sediments were collected in the final 12 km of the estuary until its mouth to the sea, where the urbanization of the Great Natal is more concentrated. Sampling was performed on 12 cross sections, with three stations each, totaling 36 samples, identified as T1 to T36. The non alkylated and alkylated PAHs were analyzed by gas chromatography coupled to mass spectrometry (GC / MS). PAHs were detected in all 36 stations with total concentration on each varying 174-109407 ng g-1. These values are comparable to those of several estuarine regions worldwide with high anthropogenic influence, suggesting the record of diffuse contamination installed in the estuary. PAHs profiles were similar for most stations. In 32 of the 36 stations, low molecular weight PAHs (with 2 and 3 ring: naphthalene, phenanthrene and their alkylated homologues) prevailed, which ranged from 54% to 100% of the total PAH, indicating that leaks, spills and combustion fuels are the dominant source of PAH pollution in the estuary. The level of contamination by PAHs in most stations suggests that there is potential risk of occasional adverse biological effects, but in some stations adverse impacts on the biota may occur frequently. The diagnostic ratios could differentiate sources of PAHs in sediments of the estuary, which were divided into three groups: petrogenic, pyrolytic and mixing of sources. The urban concentration of the Great Natal and the various industrial activities associated with it can be blamed as potential sources of PAHs in bottom sediments of the estuary studied. The data presented highlight the need to control the causes of existing pollution in the estuary / Os estu?rios s?o ambientes prop?cios ao aporte de poluentes qu?micos de diversas naturezas e origens, incluindo Hidrocarbonetos Polic?clicos Arom?ticos (HPA). Os HPA antr?picos s?o de duas fontes poss?veis: pirol?tica (com quatro ou mais an?is arom?ticos e baixo grau de alquila??o) e petrog?nica (com dois e tr?s an?is arom?ticos e alto grau de alquila??o). O presente trabalho teve como objetivo avaliar os n?veis, distribui??o e poss?veis fontes de Hidrocarbonetos Polic?clicos Arom?ticos no estu?rio do rio Potengi, Natal-RN. Amostras de sedimentos de fundo foram coletadas nos 12 km finais do estu?rio at? a sua foz, onde a urbaniza??o da Grande Natal ? mais concentrada. A amostragem foi realizada em 12 se??es transversais, com tr?s esta??es em cada uma, totalizando 36 amostras, identificadas de T1 a T36. Os HPA alquilados e n?o alquilados foram analisados por cromatografia gasosa acoplada a um detector seletivo de massas (CG/EM). Foram detectados HPA em todas as 36 esta??es, com concentra??o total em cada uma variando de 174 a 109407 ng g-1. Esses valores s?o compar?veis aos de v?rias regi?es estuarinas mundiais com grande influ?ncia antr?pica, o que sugere o registro de contamina??es difusas instaladas no estu?rio. O perfil de HPA foi similar para a maioria das esta??es. Em 32 das 36 esta??es predominaram HPA de baixo peso molecular (com 2 e 3 an?is: naftaleno, fenantreno e seus hom?logos alquilados), que variaram de 54% a 100% em rela??o ao total de HPA, indicando que vazamentos, derramamentos e queima de combust?veis s?o a fonte dominante de polui??o por HPA no estu?rio. O n?vel de contamina??o por HPA na maioria das esta??es sugere que h? risco potencial de ocasionais efeitos biol?gicos adversos serem observados, por?m em algumas esta??es se confirmam que impactos adversos sobre a biota ocorrem com freq??ncia. As raz?es diagn?sticas permitiram diferenciar as fontes de HPA nos sedimentos do estu?rio, que foram divididos em tr?s grupos: sedimentos com padr?es de introdu??o de hidrocarbonetos petrog?nicos, pirol?ticos e de mistura de fontes. A concentra??o urbana da Grande Natal e as atividades industriais diversas a ela associadas podem ser responsabilizadas como fontes potenciais dos HPA nos sedimentos de fundo do estu?rio estudado. Os dados apresentados evidenciam a necessidade de se controlar as causas da polui??o existente no estu?rio

[pt] A matéria orgânica (MO) sedimentar de origem natural na Ria de Aveiro e no estuário Mondego foi caracterizada usando a composição elementar (C e N) e lipídios biomarcadores (esteróis, n-álcoois e triterpenoides). A contribuição por esgotos foi avaliada através de coprostanol e outros esteróis fecais. Amostras de sedimento superficial foram coletadas em 22 estações ao longo das regiões. Os lipídios biomarcadores foram extraídos, purificação com sílica-gel e analisados por cromatografia em fase gasosa acoplada a espectrometria de massas. O carbono orgânico total (9,94 e 43,00 mg g(-1)) teve uma correlação com o nitrogênio total (r(2) = 0,86). A razão C/N molar (14,34 mais ou menos 1,75) foi um valor típico de MO continental. Existe uma contribuição maior de MO terrestre nas amostras, como mostra as evidencias: a predominância de n-álcoois de cadeia longa (maior ou igual à C22), maior abundancia no somatório de sitosterol, estigmasterol e campesterol sobre outros fitoesterois, como o colesterol e o brassicasterol; e a alta concentração de triterpenoides de plantas superiores, como Beta-amirina e a Alfa amirina. A concentração de coprostanol (0,05 a 16,6 microgramas g(-1)) indicou a presença de esgotos em sete estações localizadas no largo do Laranjo (S4, S5, S6, S7, S10), porto de Aveiro (S14) e no canal de Ílhavo (S16). Os aportes mais significativos foram no largo do Laranjo (S8 e S9) e no porto do Mondego (S19). / [en] The sedimentary organic matter (OM) of natural origin in the Ria de Aveiro and the estuary of Mondego River was characterized using elemental composition (C and N) and lipid biomarkers (sterols, alcohols and triterpenoids). In addition, the contribution by sewage was evaluated by coprostanol and other fecal sterols. Surface sediment samples were collected at 22 stations along the two regions. The lipid biomarkers was extracted, separated with silica-gel and analyzed by gas chromatography coupled to mass spectrometry. Concentrations of total organic carbon (9.94 and 43.00 mg g(-1)) was highly correlated with total nitrogen (r(2) = 0.86). The C/N molar ratio: 14,34 plus-minus 1,75 are typical values of OM of continental origin. There is a major contribution of terrestrially OM to the sediments, as suggested by proxies, including: predominance of long-chain (greater-than or equal to C22) alcohols, higher abundance of sitosterol, estigmasterol and campesterol over other phytosterols, like cholesterol and brassicasterol, and elevated concentrations of triterpenoids from higher plants, as Beta-amyrin and Alpha-amyrin. The concentrations of coprostanol (0.05 to 16.6 micrograms g(-1)) indicated the presence of sewage in seven stations located in the Largo do Laranjo (S4, S5, S6, S7, S10), Port of Aveiro (S14) and in Ílhavo Channel (S16). The more significant contribution of sewage was identified in the Largo do Laranjo (S8 and S9) and the Port of Mondego (S19).

No description available.

Os setores sul e norte do complexo estuarino lagunar de Cananéia-Iguape, sujeitos a diferentes pressões antrópicas, foram estudados quanto às características hidrológicas e hidroquímicas das águas de superfície e fundo, com ênfase às concentrações de zinco, cádmio e chumbo dissolvidos. A amostragem contou com coletas espaciais e temporais, em dois períodos sazonais (outono e primavera) de 2007. Os metais estudados foram: o zinco, devido ação tóxica ou como micronutriente, dependendo de sua concentração, o cádmio e o chumbo, considerados sem função biológica positiva conhecida e com alto grau de toxicidade para a biota. A metodologia utilizada na determinação da concentração dos metais traço foi a voltametria por redissolução anódica. No setor sul, a variação da salinidade foi característica de um sistema estuarino não impactado. Os teores dos metais traço encontrados sofreram variação entre 0,040 e 0,509 ?g L-1 para o zinco, 0,001 e 0,024 ?g L-1 para o cádmio e entre 0, 030 e 0,175 ?g L-1 para o chumbo. No setor norte, a variação salinidade mostrou forte influência de água doce. O zinco sofreu variação entre 0,097 e 0,257 ?g L-1, o cádmio entre 0,004 e 0,024 ?g L-1 e o chumbo 0,033 e 0,259 ?g L-1. Nos dois setores, as concentrações dos metais traço estiveram sempre abaixo dos limites propostos pela legislação ambiental brasileira (CONAMA) e norte-americana (EPAUSA). O presente estudo mostrou um maior do impacto antrópico na região norte, com potencial de exportação para o setor sul e plataforma. As maiores concentrações dos metais traço estudados ocorreram nas águas de fundo, mais próximas à interface com o sedimento. O setor sul, sujeito a uma variação da salinidade mais definida, mostrou maior potencial para a remobilização dos metais traço para a coluna de água com o movimento de maré. O estudo dos ciclos biogeoquímicos dos metais traço deve ser incentivado no monitoramento ambiental da região. / The south and north regions of Cananeia-Iguape estuarine-lagoon system submitted to different anthropic pressures were studied to evaluate their hydrological and hydrochemical characteristics mainly considering the concentrations of dissolved zinc, cadmium and lead. The sampling included spatial and temporal samples obtained in two seasons (autumn and spring) of 2007. The metals studied were zinc as a toxic agent and micronutrient depending on the concentration and cadmium and lead with no biological positive relevance and high toxicity to the biota. The methodology used in the trace metals determination was anodic stripping voltammetry. In the south portion the salinity variation was characteristic of non-impacted estuaries. The zinc concentrations ranged from 0,040 to 0,509 ?g L-1. The cadmium ranged from 0,001 to 0,024 ?g L-1. The lead content ranged from 0,030 to 0,175 ?g L-1. In the north portion, the salinity variation showed high influence of fresh water. The zinc concentrations ranged from 0,097 to 0,257 ?g L-1. The cadmium concentrations ranged from 0,004 to 0,024 ?g L-1. The lead values ranged from 0,033 to 0,259 ?g L-1. The concentration of trace metals on both portions were below the limits proposed by the Brazilian environmental law (CONAMA) and North American (EPAUSA) legislation. The present study revealed higher anthropic impact in the north region with exporting potential to the south and to the continental shelf. Higher trace metals concentrations were observed in the bottom waters near to the sediment interface. The south region, submitted to most defined tide movements, showed an important potential for trace metals remobilization to the water column. The trace metals biogeochemistry cycles study should be enhanced for better environmental monitoring.