Dissertations / Theses on the topic 'Estuarine processes'
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Mendes, Renato Paulo dos Santos. "The Douro estuarine plume: detection, processes and dynamics." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17073.
Full textO Douro é um dos maiores rios da Península Ibérica, constituindo a maior descarga de água doce para o Oceano Atlântico na costa noroeste portuguesa. A sua pluma estuarina tem particular relevância na dinâmica costeira e na modulação de fenómenos biogeoquímicos. São objetivos desta dissertação contribuir para a compreensão dos processos físicos associados à geração e propagação da pluma estuarina do Rio Douro no oceano, assim como para o conhecimento dos seus padrões de dispersão e da forma como estes alteram a hidrologia e a circulação costeira, considerando os agentes forçadores típicos deste fenómeno (caudal fluvial, vento e maré) e índices climáticos relevantes. Para concretização destes objetivos foram desenvolvidas e aplicadas metodologias inovadoras de processamento de dados de deteção remota, assim como novas implementações estuarinas e costeiras de modelos numéricos. Através de imagens MODIS, otimizadas para o estudo de fenómenos costeiros, efetuou-se uma deteção rigorosa da pluma. Identificou-se uma relação entre o sinal túrbido nLw555 e o caudal, demonstrando-se este produto como um bom proxy para a observação da pluma no oceano. As escalas temporais e espaciais da pluma foram caraterizadas através destas imagens, combinadas com dados de caudal fluvial, maré, vento e precipitação, e também com índices climáticos relevantes. Para compreender a propagação da pluma e caracterizar a sua dinâmica e impacto na circulação costeira, foi desenvolvida uma aplicação 3D de modelos estuarinos e costeiros com malhas aninhadas de resolução variável. Definiramse e analisaram-se diferentes cenários de vento e descarga fluvial. A interação da pluma do Rio Douro e do Minho foi ainda analisada através dos resultados de simulações baseadas num evento de inverno. Os compósitos túrbidos mostraram que a pluma é facilmente detetada quando o caudal é maior que 500 m3 s1. A descarga fluvial e o vento são os principais forçadores da sua propagação, enquanto a maré é apenas importante na região próxima à embocadura do estuário. Observaram-se relações a uma escala interanual entre a turbidez da pluma e os índices climáticos East Atlantic e NAO, com uma correlação máxima identificada com 1 e 3 meses de desfasamento, respetivamente. Com base nos resultados das simulações efetuadas, a pluma é classificada como de larga escala e de adveção superficial, apresentando características de uma pluma prototípica. Em condições de caudal moderado a elevado, a descarga estuarina é suficiente para gerar uma corrente costeira para norte sem ação do vento. Em eventos de ventos leste, a propagação da pluma é similar ao caso sem vento, com um aumento da velocidade da corrente. Uma corrente costeira para sul é unicamente identificada sob condições de forte vento de oeste. Ventos de norte tendem a estender a pluma para o largo, com uma inclinação na direção sudoeste, enquanto ventos de sul intensificam a corrente para norte, sendo a mistura das plumas do Douro e do Minho uma consequência possível. A análise desta interação apontou a contribuição do Douro como importante na estabilização da WIBP e nas trocas de água entre o oceano e as Rias Baixas. A interação da pluma do Douro com estuários localizados a sul da sua foz e a confirmação in situ da recirculação observada nos resultados numéricos afiguram-se como temas relevantes para investigações futuras.
The Douro is one of the largest rivers of the Iberian Peninsula, representing the most important freshwater input into the Atlantic Ocean (on the northwestern Portuguese coast). Its estuarine plume has particular relevance on coastal dynamics and biogeochemistry. The main goal of this dissertation is to contribute to increase knowledge on physical processes associated with the generation and propagation of the Douro estuarine plume. The general patterns of dispersion in the ocean and how the plume change hydrography and coastal circulation were also evaluated, considering the typical drivers involved (river discharge, wind and tide) and relevant climate indices. Innovative methodologies to process remote sensing data, as well as new implementations of high-resolution estuarine and coastal numerical models have been developed and applied. The plume was detected through MODIS images, optimized for coastal studies. The relation between the turbid nLw555 signal and river discharge was identified, demonstrating that this product is a good proxy for the observation of the Douro estuarine plume in the coastal ocean. An interconnected approach, combining these images, river discharge, tide, wind and precipitation data, as well as relevant climate indices, was used to study the temporal and spatial scales of the plume. The implementation of estuarine and coastal models with nested domains of variable resolution was developed to understand the plume propagation and characterize its dynamics and impact on coastal circulation. Using these applications, different scenarios of wind and river discharge were defined and analysed. The interaction of the Douro and the Minho estuarine plumes was further evaluated through simulations based on a winter event. Turbid composites showed that the plume is easily detected when river discharge is greater than 500 m3 s1. River discharge and wind are the main driver acting on the plume propagation, whilst tidal effect is only important near the estuary mouth. A relation between turbid plume and climate indices East Atlantic (EA) and North Atlantic Oscillation (NAO) was observed at inter-annual scale, with a maximum correlation identified at 1 and 3-month lags, respectively. The Douro estuarine plume is classified as large-scale and surface-advected, presenting characteristics of a prototypical plume, based on the results of the numerical simulations. The estuarine outflow is sufficient to generate a northward coastal current without wind action under moderate-to-high river discharge conditions. Under easterly winds, the propagation pattern is similar to the case without wind forcing, with a slight increase in the northward current. A southward coastal current is only generated by strong westerly winds. Under upwellingfavourable winds, the plume extends offshore with tilting towards southwest. Southerly winds increase the velocity of the northward current, being the merging of the Douro and Minho estuarine plumes a likely consequence. The analysis of this interaction pointed out the Douro as an important contributor to the WIBP stabilization and in the water exchange between ocean and Rias Baixas. The interaction of the Douro estuarine plume with estuaries located south of its inlet and the in situ confirmation of the re-circulation bulge observed in numerical results seem as relevant for future research topics.
Al-Enezi, Eqbal Hussain. "Modelling of phosphorus adsorption processes in estuarine and coastal water." Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/54203/.
Full textCoffey, Michael. "The behaviour of trace metals in the Humber Estuary, U.K." Thesis, University of East Anglia, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240991.
Full textSouza, Rogério Riker de. "Modelagem numérica da circulação de correntes de maré na Baía de Marajó e Rio Pará (PA)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3147/tde-19092006-154712/.
Full textIn the amazonic region, navigation is the natural and leading, in some cases the only one possibility, role in the transportation network. In this scenario, the thesis has the main purpose of consolidating the knowledge about tidal currents pattern in Marajó Bay and Pará River (PA), considering Vila do Conde Harbour as the most important study area. A best knowledge about the tidal currents will be an important factor for port and waterway planning, contributing to increase the port operation safety and development. The tidal currents pattern was consolidated through numerical modelling using DHI MIKE 21 HD software, which is a bidimensional vertically integrated model. A bibliographical review was carried out about correlated themes: currents, tides and winds, and also was made a data base research, which was used in the numerical model calibration and validation. Due to the few data obtained, calibration was performed with Vila do Conde Harbour data, using current intensity and directions obtained in 1991 and 2001 surveys. The validation was performed using the Tidal Currents Chart, for a point in the Marajó Bay. The software results showed a consistent fit to the real condition, which made possible to get a Tidal Currents Chart of the whole area and for the focus area.
Dyson, Kirstie Elizabeth. "Biodiversity and ecosystem processes in heterogeneous environments /." St Andrews, 2008. http://hdl.handle.net/10023/698.
Full textKenny, Carolyn. "Nitrogen transformation processes and nitrous oxide evolution in estuarine intertidal zones." Thesis, Royal Holloway, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417365.
Full textSmar, Daina. "An assessment of ecological processes in the Apalachicola estuarine system, Florida." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5506.
Full textM.S.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering; Water Resources Engineering
Yannaccone, John A. "Numerical simulation of the effects of sea level rise on estuarine processes." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/50072.
Full textMaster of Science
incomplete_metadata
Budi, Santoso Eko. "Tidal anomalies at river entrances and the physical processes which generate them /." St. Lucia, Qld, 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17707.pdf.
Full textGomes, Filho Jose Gerardo Ferreira. "Pre- and post-settlement processes influencing the distribution of barnacles along estuarine gradients." Thesis, University of Plymouth, 2007. http://hdl.handle.net/10026.1/2409.
Full textWeaver, Andrew John. "Numerical and analytical modelling of oceanic/atmospheric processes." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27560.
Full textScience, Faculty of
Mathematics, Department of
Graduate
Gao, Guanghai. "Numerical modelling of hydrodynamic and sediment-bacteria interaction processes in estuarine and coastal waters." Thesis, Cardiff University, 2008. http://orca.cf.ac.uk/54738/.
Full textGeronilla, Kristina. "Re-presenting the Waterfront: revealing the intersection of human and natural processes." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/35894.
Full textMaster of Landscape Architecture
Cahyono, M. "Three-dimensional numerical modelling of sediment transport processes in non-stratified estuarine and coastal waters." Thesis, University of Bradford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520623.
Full textPidduck, Emma Louise. "The importance of micro-scale processes on the release of macro-nutrients from estuarine suspended sediments." Thesis, University of Plymouth, 2016. http://hdl.handle.net/10026.1/5378.
Full textVinson, Joshua S. "Role of oxygen and salinity on biogeochemical processes controlling mercury and monomethylmercury flux from estuarine sediments." View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-2/r1/vinsonj/joshuavinson.pdf.
Full textJosko, Troselj. "FLUVIAL INFLUENCE ON ESTUARINE SEDIMENT TRANSPORT PROCESSES AND LINKAGE OF ITS OUTFLOW DATA TO COASTAL MODELING." Kyoto University, 2016. http://hdl.handle.net/2433/217745.
Full textMarvan, Fernando G. "A two-dimensional numerical transport model for organic-rich cohesive sediments in estuarine waters." Thesis, Heriot-Watt University, 2001. http://hdl.handle.net/10399/1212.
Full textEnot, Patricia. "Physical and geochemical processes affecting fate of low-pH leachate and associated metal contaminants in an estuarine aquifer." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/13801.
Full textSchindler, Jennifer. "Estuarine Dynamics as a Function of Barrier Island Transgression and Wetland Loss: Understanding the Transport and Exchange Processes." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1260.
Full textShi, Jie. "Integrated modelling of hydrological and hydrodynamic processes, dynamic bacteria decay with climate change and intensive farming in riverine and estuarine water." Thesis, Cardiff University, 2016. http://orca.cf.ac.uk/98617/.
Full textRubio, Zuazo Ana Maria, and anarubio zuazo@gmail com. "Environmental influences on the sustainable production of the Sydney rock oyster Saccostrea glomerata : a study in two southeastern Australian estuaries." The Australian National University. Centre for Resource and Environmental Studies, 2008. http://thesis.anu.edu.au./public/adt-ANU20080618.091057.
Full textMfikili, Athi Nkosibonile. "Influence of sedimentological and hydrological processes on the distribution of the Spartina maritima salt marsh in the Keurbooms Estuary, Western Cape." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/13004.
Full textNavera, Umme Kulsum. "Development of a model for predicting wave-current interactions and sediment transport processes in nearshore coastal waters." Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/55916/.
Full textHarbison, John Edwin. "Groundwater chemistry and hydrological processes within a Quaternary coastal plain: Pimpama, Southeast Queensland." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16647/1/John%20Harbison%20Thesis.pdf.
Full textHarbison, John Edwin. "Groundwater chemistry and hydrological processes within a Quaternary coastal plain: Pimpama, Southeast Queensland." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16647/.
Full textBuzzelli, Christopher P. "Integrative analysis of ecosystem processes in the littoral zone of lower Chesapeake Bay: A modeling study of the Goodwin Islands National Estuarine Research Reserve." W&M ScholarWorks, 1996. https://scholarworks.wm.edu/etd/1539616592.
Full textNoernberg, Mauricio Almeida. "Processos morfodinâmicos no complexo estuarino de Paranaguá - Paraná - Brasil : um estudo a partir de dados in situs e Landsat-TM." reponame:Repositório Institucional da UFPR, 2001. http://hdl.handle.net/1884/48786.
Full textCo-orientadores: Rodolfo José Angulo, Evlyn M. L.M. Novo
Acompanha CD-ROM
Tese (doutorado) - Universidade Federal do Paraná
Resumo: A análise morfodinâmica do sistema costeiro aborda os processos causadores e transformadores de feições morfológicas, bem como as forças geradoras desses processos e seus mecanismos de interação. A grande variabilidade espacial e temporal dos processos costeiros e estuarinos é um desafio para o entendimento geral tanto da freqüência quanto da magnitude desses processos, bem como de seu grau de influência no transporte e balanço de sedimentos, na morfologia costeira e nos processos ecológicos. A capacidade de análise sinóptica das imagens de satélite, dados históricos e obtidos in situ, e o potencial de análise espacial do geoprocessamento, foram empregados na identificação e compreensão dos processos morfodinâmicos no Complexo Estuarino de Paranaguá (CEP) e região costeira adjacente. O CEP possui dois eixos principais (L-0 e N-S), cujas condições ambientais (salinidade, temperatura, correntes, sólidos em suspensão, turbidez e clorofila) foram monitoradas mensalmente durante 26 meses. O eixo L-O, comparado ao eixo N-S, apresenta maior produtividade primária e sofre maior influência da bacia de drenagem. Os processos estuarinos, mais importantes, relacionados ao transporte de sedimentos são o aporte de sedimentos fluviais, de escala temporal sazonal e episódica, e a zona de máxima turbidez, a qual é regulada pela maré de sizígia. Nas margens arenosas da desembocadura do CEP, a evolução da linha de costa foi monitorada, entre 1985 e 2000, por oito imagens do satélite Landsat, as quais se mostraram úteis para tal finalidade. As alterações morfológicas apresentam padrões diferenciados de resposta, em diferentes locais da desembocadura, sob a ação das forçantes (ondas, correntes e ventos). As alterações de maior magnitude estão relacionadas à modificação no padrão anual de ventos, que por sua vez influi no estado de agitação do mar, sendo a intensificação de ventos dos quadrantes Sul e Sudeste indutora de processos erosivos. Há indícios de que estas alterações no padrão de ventos e a conseqüente variação na linha de costa estejam vinculadas ao momento de inversão entre os eventos El Nino-La Nina. O comportamento das correntes na região costeira foi descrito, e o transporte de sedimentos por tração foi estimado, utilizando dados obtidos por correntômetro eletromagnético no canal de acesso ao CEP. A deriva litorânea foi confirmada como sendo preferencialmente para Norte. O transporte por tração dos sedimentos de fimdo ocorre tranversalmente e longitudinalmente à linha de costa. As correntes de maré são as causadoras do transporte transversal à costa, o qual predomina no sentido costa afora. O transporte longitudinal à costa ocorre quase exclusivamente em momentos de intensa energia de ondas e preferencialmente para Norte. Uma imagem Landsat-7 foi obtida em um desses momentos de intensa energia, geralmente ocasionados devido à entrada de frentes meteorológicas, onde três tipos de processos costeiros (pluma estuarina, correntes de retomo e frente de superfície), relacionados a transporte de sedimentos, puderam ser descritos. A pluma estuarina, intensificada pela ressuspensão dos sedimentos de fimdo, ultrapassou a isóbata dos 20 metros. Correntes de retomo erosivas foram vinculadas a um processo de circulação de maior magnitude, envolvendo troca de propriedades entre a zona de surfe e a plataforma rasa. Fortes correntes de maré vazante de sizígia e a ressuspensão de sedimentos regularam o processo de evolução de uma frente de superfície de escala temporal de 30 horas e escala espacial da ordem de 10 km. Nesta frente foi observado transporte de sedimentos tanto transversalmente quanto ao longo da linha de costa. O CEP é particularmente vulnerável a eventos de grande energia que nele atuam, principalmente na escala temporal "evento" (dias a meses) e age como um fomrcedor de propriedades (sedimentos, nutrientes, poluentes) para a plataforma rasa. Palavras-chave: Morfodinâmica; Processos; Estuário; Zona Costeira; Transporte de Sedimentos; Monitoramento Ambiental; Landsat; Linha de Costa; Baía de Paranaguá.
Abstract: The moiphodynamic analysis of coastal systems can be applied to the study of processes that generate and transform morphologic features, as well as to understand the forcings of those processes and their interaction mechanisms. The great space and temporal variability of coastal and estuarine processes are a challenge for the general understanding of the frequency and magnitude of those processes, its influence on the sediment transport and budget, in the coastal morphology and ecological processes. The capacity of synoptic analysis of satellite images, historical data and in situ collected information, as well as the potential of geoprocessing for space analysis, were used in the identification and understanding of the morphodynamic processes in the Estuarine Complex of Paranaguá (CEP) and adjacent coastal area. The CEP has two main axes (E-W and N-S), whose environmental conditions (salinity, temperature, currents, suspended particulate matter, turbidity and chlorophyll) were monthly monitored during 26 months. The E-W axis compared to the N-S axis presents larger primary productivity and it suffers larger influence of the drainage basin. The more important estuarine processes are related to the transport of sediments, the contribution of fluvial sediments, and some episodic phenomena as well as other of seasonal scale. The maximum turbidity zone is regulated by the spring tide dynamic. In the sandy margins of the outlet of the CEP, the evolution of the coastline was monitored between 1985 and 2000 using eight Landsat images, which were shown useful for such purpose. The morphologic alterations showed differentiated patterns of response in different places of the outlet and under the action of the main acting forces (waves, currents and winds). The larger alterations are related to the modification in the annual pattern of winds, which influences the sea state. The intensification of winds of South and Southeast responsible for erosional processes. There are indications that these inter-annual alterations in the wind regime, and the consequent variation in the coastline, are linked to transition among the El Nino to La Nina events. The current behaviour in the coastal area was described, and the bedload transport of sediments was estimated using data obtained by electromagnetic currentmeters moored in the access channel of the CEP. The drift current was confirmed as being drive mainly to North. The bedload transport of the bottom sediments happens across and along the coastline. The tidal currents are responsible for the across-coast transport, which prevails in the seaward sense. The longitudinal transport happens almost exclusively in events of intense wave energy and mainly to the North. A Landsat-7 image was obtained in one of those moments of intense energy, generally due to the passage of meteorological fronts, where three types of coastal processes related to the sediment transport (estuarine plume, rip currents and surface front) could be described. The estuarine plume, intensified by the ressuspension of the bottom sediments, surpassed the isobath of 20 meters. Erosional rip currents were linked to a larger magnitude circulation process, involving change of properties between the surf zone and the inner continental shelf. High flooding spring tidal currents and the sediments ressuspension seems to regulate the evolutionary process of a surface front of temporary scale of around 30 hours and a space scale of the order of 10 km. In this front, sediment transport was observed obliquely as well as along the coastline. The CEP is particularly vulnerable to events of great energy that act in it, mainly in the "event" time scales (days to months) and it acts as an exporter of properties (sediments, nutrients, pollutants, etc.) for the inner continental shelf. Key Words: Morphodynamic Processes; Estuary; Coastal Zone; Sediments Transport; Environmental Monitoring; Landsat; Coastline; Bay of Paranaguá.
Siqueira, Bibiana Kumpera. "Contribuição ao processo sedimentar atual no Canal do Ararapira, sistema estuarino-lagunar de Cananéia-Iguape (SP)." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/21/21133/tde-01072008-102612/.
Full textThe aim of this study is the analysis of modern sedimentary process taking place in the Ararapira Channel, at Cananéia-Iguape lagoonal estuarine system (SP). The employed parameters for this were the composition and grain size characteristics of the bottom sediments , the distribution of the carbonates , organic matter, and relates these parameters to the general configuration of the channel and to the oceanographic process that takes place over there. The grain size analysis, the carbonate content, and the sediment organic matter (C, N, S) were conducted over 60 sediment samples collected during an oceanographic cruise that took place in July 2004. Among the total of the 60 samples, 16 were selected for the coarse fraction analysis. The spatial analysis of the distribution of sediments and sedimentary organic matter showed that sandy sediments, with low organic content, are predominant practically all along the whole of the channel extension, except in points located in the central-northern portion of the channel, where there are thin sediment associated to shoals or small continental and insular river courses. The C, N, S and carbonates contents observed with the coarse fraction analysis, allow identifying the predominance of continental influence all along the channel, with lower carbonate concentrations. The sediment organic matter contents have, usually, behavior and distribution which are directly related to the type of sediment ,to the bottom topography, as well as to the circulation. It was possible to observe a direct relationship between the thin sediment and a larger content of the organic matter.
Mahamod, Yusuff. "Sedimentary processes in the Dwyryd Estuary." Thesis, Bangor University, 1989. https://research.bangor.ac.uk/portal/en/theses/sedimentary-processes-in-the-dwyryd-estuary(ca0aea23-480c-4032-ba10-12a9adee740c).html.
Full textMhashhash, Aisha Fowzi. "Laboratory and numerical modelling studies of sediment flocculation processes in estuaries." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/114776/.
Full textRouas, Guy. "Étude et modélisation par éléments finis des processus hydrosédimentaires estuariens." Compiègne, 1996. http://www.theses.fr/1996COMPD884.
Full textLe, Normant Catherine. "Modélisation numérique tridimensionnelle des processus de transport des sédiments cohésifs en environnement estuarien." Toulouse, INPT, 1995. http://www.theses.fr/1995INPT014H.
Full textQu, Wenchuan. "Studies on nitrogen cycling processes in Lake Illawarra, New South Wales, Australia." Access electronically, 2004. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20050302.161641/index.html.
Full textLisa, Jessica A. "Linking structure and function of microbial communities responsible for sedimentary nitrogen processes in North Carolina estuaries." W&M ScholarWorks, 2015. https://scholarworks.wm.edu/etd/1539616745.
Full textAndutta, Fernando Pinheiro. "O Sistema Estuarino dos rios Caravelas e Peruípe (Bahia): Observações, simulações, tempo de residência e processos difusivo e advectivo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/21/21132/tde-27072011-150459/.
Full textThe numerical model Delft-Flow was used to study the spatial distribution and variability of the termohaline properties, and the tridimensional circulation in the estuarine system of the rivers Caravelas and Peruípe. The model results were validated quantitatively using field data of tidal oscilation and currents, and salinity measurements during neap and spring tides at four mooring stations, two in each estuary. In the data processing homogeneous conditions were used initially for the fields of salinity, density and the vertical kinematic coeficients of viscosity and diffusivity, then after four weeks of running simulation those fields were saved with spatially varied conditions. Those results were used for a more realistic initial condition, thus having a varied field of the termohaline properties, and of the physical parameters. The new initial conditions allowed avoiding the transient time and thus optimizing the following simulations. The model evaluation was done based on measurements undertaken during the summer season, because of the delay in the raining season, the Peruípe river discharge was low and more representative of dry season condition, for those reasons we just used the measurement taken in the January 2008. In the summer the measurements of the Peruíbe river discharge taken from the Agência Nacional de Águas (ANA), and the river flow of was estimated at ~ 20 m3.s-1, with the extrapolation of ~ 4 m3.s-1 for the unified flow from the rivers Cúpido and Jaburuna, with contribute to the flow in the Caravelas estuary. Tidal oscillation at neap and spring tides were well simulated for the 4 controling sites used to the validation, and with the mean skill values over 0.97. The tidal amplitudes were numerical calculated and nearly between 1.3 and 2.5 meters at neap and spring tides, respectively. The numerical results of the velocities were better simulated in spring tides with the mean skill values in the range of 0.77 and 0.93, while at neap tides this parameter varied between 0.38 and 0.65. For the salinity structure at spring tides good results in the estuarine system were achieved, hence comprising all the controling station for validation, with all mean skill values over 0.83. At neap tides the corresponding mean skill values were relatively high, varing in the range of 0.73-0.85. In addition, there were difficulties in simulation adequately the highly vertical and longitudinal stratification of the Nova Vicosa estuary. That was caused by the stronger river inflow of the Peruípe River, which is much higher than the inflow by Caravelas River. The intrusion of the Tropical Water mass (TW) was properly simulated given the right distribution of the salinity along the first quilometers of the estuarine channel of Caravelas, and the internal part of the Nova Viçosa estuarine mouth. Bidirectional movements were observed from the model outputs at the high and low tides, at the region near the mouth of both, Caravelas and Nova Viçosa estuary. Those moviments are forced by the baroclinic component of the pressure gradient. Is worth to mention the the baroclinic effect was better observed at the low tides of these regions. At high tide most of areas showed only a small change in the current direction between surface (Z = -0.1) and bottom (Z = -0.9) and usually smaller than 30 degrees. The virtual lagrangian drifters released along the estuarine channels of Caravelas (north) and Nova Viçosa (south) have shown a residence time relatively short, and comparable to the Curimataú tropical estuary. In the released location between 3 and 12 km of distance from the Caravelas mouth, the residence time was in the range of 4.2 and 10.3 days. Differently, at the Nova Viçosa estuary, only the first 5 km were studied and the residence time of 1.5 and 2.5 days was estimated for the respectives positions of 2.5 and 5.0 km away from the mouth. The analytical model proposed and used to calculate the residence time leaded to results comparable to the results from the numerical simulation using the Lagrangian method of the Delft-3D Flow. Differently, the LOICZ model has shown results really different of the residence time for all the six estuaries (Caravelas, Nova Viçosa, Curimataú, Hudson, Conwy and Mersey), and in general much smaller then the results from the proposed formula, thus indicating a possible overestimation of the diffusive flux assumed in the LOICZ formulation.
Rybarczyk, Hervé. "Processus d'eutrophisation et ses consequences sur les peuplements d'un ecosysteme estuarien macrotidal, un exemple en manche orientale : la baie de somme." Paris 6, 1993. http://www.theses.fr/1993PA066231.
Full textSantos, Marcus Vinicius Peralva. "Utilização dos Componentes Biogênicos do Sedimento na Interpretação de Processos Sedimentares na Região Estuarina do Rio Jacuípe, Litoral Norte da Bahia." Instituto de Geociências, 2012. http://repositorio.ufba.br/ri/handle/ri/21499.
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O presente trabalho teve como objetivo analisar os processos de sedimentação, transporte e energia hidrodinâmica atuantes na região estuarina do rio Jacuípe, Litoral Norte da Bahia, utilizando-se, para este fim, os componentes biogênicos do sedimento. Foram realizadas duas campanhas amostrais, uma na estação seca e outra na estação chuvosa, obtendo-se um total de 32 amostras de sedimento superficial de fundo, por campanha amostral, ao longo do canal principal do estuário, por meio de dragagem. Após lavagem e secagem das amostras, os 300 primeiros grãos bioclásticos foram submetidos a triagem, identificação e descrição de seus aspectos tafonômicos (coloração, desgaste e arredondamento), sendo parte das amostras submetidas a análise da fauna de foraminíferos, teor de carbonato e a analise granulométrica. Os resultados obtidos foram submetidos aos tratamentos estatísticos de abundância (absoluta e relativa), testes de Spearmann e Mann-Whitney e as análises de regressão simples e múltipla. Constatou-se o predomínio das categorias biogênicas madeira, alga, foraminífero bentônico e tecameba, sendo a distribuição dos grãos influenciada pela ação das corrente marinhas e fluviais. Grãos como algas calcárias, Halimeda, briozoários, cnidários, poliquetas, caranguejo, craca, gastrópodo, bivalve e escafópodo tendem a se concentrar nas regiões próximas a desembocadura do estuário, enquanto fragmentos de diatomácea, tecameba e foraminíferos planctônicos, tendem a se concentrar na região central do estuário e as demais categorias apresentaram distribuição variada. A dominância de grãos sem arredondamento, com abrasão e de coloração branca em ambas as estações, indicam um incremento constante de novos grãos ao estuário, sendo o transporte dos mesmos ocorrendo preferencialmente via arrasto. As testas de foraminíferos mostraram-se bem preservadas (grãos naturais) e com predomínio da coloração branca, indicando um transporte por suspensão das mesmas. Os valores do teor de carbonato indicam uma maior contribuição siliciclástica ao estuário e a granulometria predominante é a areia fina. Com base nos resultados obtidos, pode-se assim, descrever o estuário do rio Jacuípe como sendo um estuário de sedimentação recente (dominância de grãos atuais), com o transporte de grãos ocorrendo preferencialmente via arrasto (dominância de grãos abrasados) e por uma baixa energia hidrodinâmica em ambas as estações (dominância da fração areia fina), não sendo possível relacionar qual parâmetro ambiental influencia a distribuição dos bioclastos.
ABSTRACT - This study aimed to analyze the processes of sedimentation, hydrodynamic transport and energy working on the estuary of the river Jacuípe, north coast of Bahia, using for this purpose, the components of the biogenic sediment. There were two sampling campaigns, one in the dry season and another in the rainy season, resulting in a total of 32 surface sediment samples from the background by sampling campaign along the main channel of the estuary by dredging. After washing and drying of samples, the first 300 bioclastic grains were subjected to screening, identification and description of Taphonomic aspects (color, wear and rounding), being part of the samples and analysis of the fauna of foraminifera, carbonate content and particle size analysis . The results were subjected to statistical treatment of abundance (absolute and relative), Spermann tests and Mann-Whitney and analysis of simple and multiple regression. It was observed the predominance of biogenic categories wood, algae, benthic foraminifera and tecameba, and the distribution of grains influenced by the action of ocean currents and river. Grains such as calcareous algae, Halimeda, bryozoans, cnidarians, polychaetes, crabs, barnacles, gastropods, bivalves and escafópodo tend to be concentrated in areas near the mouth of the estuary, while fragments of diatom, and planktonic foraminifera tecameba, tend to concentrate in the region central estuary and the other categories showed varied distribution. The dominance of grain without rounding, abrasion and white coloration in both seasons, indicating a constant growth of new grains to the estuary, and transport occurs preferentially via the same drag. The foraminifers tests showed well preserved (natural grain) and predominantly white in color, indicating a suspension of transport for them. The values of carbonate content indicate a greater contribution to the estuary and siliciclastic grain size is predominantly fine sand. Based on these results, one can thus describe the estuary of the river as an estuary Jacuípe sedimentation recent (current dominance of grains), with the transport of grains occurs preferentially via drag (dominance of abrasive grains) and a low hydrodynamic energy in both seasons (dominance of fine sand fraction), it is not possible to relate environmental parameter which influences the distribution of bioclasts.
Calado, Leonardo Luiz. "Mapeamento cromoss?mico de genes ribossomais em esp?cies estuarinas da fam?lia Gerreidae Identifica??o de uniformidade cariot?pica e sua empregabilidade com fins biotecnol?gicos - REPROGEN." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12653.
Full textConselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Perciformes are dominant in the marine environment, characterized as the largest and most diverse fish group. Some families, as Gerreidae, popularly known as silver jennies, carapebas, or mojarras have a high economic potential to marine fish farming, natural explotation and game fishing. Genetic information of these species are of fundamental importance for their management and production. Despite exist over 13,000 marine fish species described, only 2% were cytogenetically analyzed and less than 1% have some reproductive characteristics known. Induced breeding, cytogenetic characterization and cryopreservation of gametes, represent important areas in applied fish studies. In this project cytogenetic analyzes were performed to acess genetic aspects of Gerreidae species, distributed in coastal and estuarine regions of Northeast Brazil. Different methods for identifying chromosomal regions were employed using conventional techniques (Ag-NORs, C-banding), staining with base-specific fluorochromes (DAPI-CMA3), and physical mapping of ribosomal genes 18S and 5S rDNA, through hybridization in situ with fluorescent probes (FISH). The six species analyzed showed remarkable chromosome conservatism. The 18S and 5S ribosomal genes when analyzed in phylogenetic perspective demonstrate varied evolutionary dynamics, suggesting ocurrence of stasis process in some groups and greater dynamism in others. Double FISH with 18S and 5S probes showed both how efficient cytotaxonomic markers in the homogeneous karyotypes of this group of species. The karyotypic pattern identified in addition to the evolutionary aspects of karyotype, are suggestive of existence of low potential of post-zygotic barrier, prompting further research to prospect for artificial interspecific hybridization of these species of commercial importance
Os Perciformes s?o dominantes no ambiente marinho, contituindo a maior e mais diversificada ordem de peixes dentre os tele?steos. Muitas de suas fam?lias, como os Gerreidae, conhecidos popularmente como carapicus, carapebas, ou mojarras, t?m um alto potencial econ?mico, no que se diz respeito ? piscicultura marinha, extrativismo e pesca esportiva. Informa??es gen?ticas destas esp?cies s?o de fundamental import?ncia para seu manejo e produ??o. Mesmo assim, das 13.000 esp?cies de peixes marinhos descritos, apenas 2% foram estudadas sob o ponto de vista citogen?tico e menos de 1% sobre suas caracter?sticas reprodutivas. A reprodu??o induzida, a citogen?tica e a criopreserva??o de gametas, representam importantes ?reas aplicadas de estudo em peixes. No presente trabalho an?lises citogen?ticas foram empregadas na caracteriza??o gen?tica de esp?cies da fam?lia Gerreidae, ocorrentes no litoral do Nordeste do Brasil. Diferentes m?todos de identifica??o de regi?es cromoss?micas foram empregados por meio de t?cnicas convencionais (Ag-RONs, bandamento C), colora??o com fluorocromos base-espec?ficos (DAPI-CMA3), e mapeamento cromoss?mico de genes ribossomais marcadores DNAr 18S e 5S, atrav?s da hibrida??o in situ com sondas fluorescentes (FISH). As seis esp?cies analisadas revelaram marcante conservadorismo cromoss?mico. Os genes ribossomais 18S e 5S quando analisados em perspectiva filogen?tica, demonstram din?mica evolutiva variada, podendo apresentar estase em alguns grupos e maior dinamismo em outros. As an?lises por duplo-FISH dos s?tios 18S e 5S se revelaram eficientes marcadores citotaxon?micos nos cari?tipos homog?neos deste grupo de esp?cies. Os padr?es cariot?picos identificado, al?m dos aspectos evolutivos do cari?tipo identificados, s?o sugestivos de baixo potencial de barreiras p?s-zig?ticas, instigando pesquisas futuras de prospec??o de hibrida??o interespec?fica destas esp?cies de valor comercial
Bachelet, Guy. "Processus de recrutement et rôle des stades juvéniles d'invertébrés dans le fonctionnement des systèmes benthiques de substrat meuble en milieu intertidal estuarien." Bordeaux 1, 1987. http://www.theses.fr/1987BOR10568.
Full textBachelet, Guy. "Processus de recrutement et rôle des stades juvéniles d'invertébrés dans le fonctionnement des systèmes benthiques de substrat meuble en milieu intertidal estuarien." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37602511w.
Full textMarion, Claire. "Processus de sédimentation fine en domaine estuarien macrotidal : approche trans-disciplinaire et multi-échelles : application à l'estuaire de l'Authie, Nord de la France." Littoral, 2007. http://www.theses.fr/2007DUNK0188.
Full textThe mechanisms controlling fine sediments dynamics in estuaries are complex because of the multiplicity of active processes and their diverse interactions, most often not well understood. The study of fine sediment dynamics embodies a number of fundamental environmental issues. Due to their strong affinity with a large range of metallic and organic contaminants, fine-grained deposits are capable of concentrating pollutants from watersheds and from the sea, both of which are sources of increasing coastal zone hazards (from agriculture, maritime traffic. . . ). Accretion of estuarine deposits leads to mudflat formation, and then salt marsh establishment, thus forming habitats of supreme importance in the European community. The lasting biodiversity and resource value of these habitats are at risk from accelerated estuarine infilling. The objective of this thesis has been to highlight key points of the functioning of an estuary co-dominated by waves and tides, and to gain better insight into the interactions underlying fine-grained sedimentation processes. The approach is highly methodological, based on the application of a cross-disciplinaryassemblage of tools. The study shows that wave influence, though significant, is restricted to the esturary mouth. The esturary exhibits freshwater/salinity mixing and the presence of a turbidity maximum resulting from a combination of tidal asymmetries. This tidal pumping is capable of very widely redistributing the sediment within the estuary, notably via macrofloc dynamics. Interactions between tidal asymmetry and morphology are complex and, through generated residual transport, condition the evolution of the estuarine system. The tidal dynamics are particularly well recorded by the characteristics of deposited sediments and their clear rhythmic pattern. The monitoring has shown the constant availability of sediment in the water column and the key role of tidal channels as vectors of sediment circulation. The input of sediment over the intertidal zones is governed by elevation within the tidal frame. The different results have highlighted the importance of Spartina in sediment trapping mechanisms over salt marshes and their seasonal variability but also the medium-term impacts of high sedimentation rates on benthic biocoenoses. At longer timescales, investigation of the consequences of this accretion highlights the effect of compaction of the sedimentary profile. The stratigraphic input from this work takes into account conclusions from the Holocene history of the neighbouring Flemish coastal plain, and confirms the advanced stage of infilling of the Authie esturay. The research on the Authie estuary may be summarised by a model of an estuary with mixed wave-tide hydrodynamic dominance pertinent to temperate macrotidal estuaries located in sand-rich tidal seas with storm wave influence, which is precisely the case of English Channel estuaries. Climatic perturbations and natural variability initiated within the frame of global change result in increasing human pressures on estuaries, thus generating potential risks. Tacking these pressures and risks calls for a holistic approach to the study of estuarine ecosystems, not only at the regional scale of the English Channel, but also in the world context
Joaquim, João Marcos Barreiros. "Avaliação da composição das águas e dos processos de circulação e mistura no sistema estuarino-lagunar do Itapocu, como subsídio ao ordenamento do uso da água." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/94558.
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O presente trabalho busca um entendimento dos processos de circulação e mistura no Sistema Estuarino-lagunar do Itapocu, entre os municípios de Barra Velha e Balneário Barra do Sul. A pesquisa visa o entendimento desses processos tendo como objetivos a determinação dos principais parâmetros físico-químicos da coluna d'água, tendo como referências a salinidade, temperatura, turbidez, oxigênio dissolvido e pH. Além desses parâmetros foi realizada uma investigação sobre o padrão de circulação das correntes nas proximidades da desembocadura do Sistema Estuarino-lagunar do Itapocu, a aquisição desses dados foi viabilizada pela utilização de um ADCP, que realiza um perfilação identificando as direções e velocidades das correntes. A estratégia amostral foi definida contemplando quatro campanhas amostrais, uma a cada estação do ano, para que se obtivesse uma leitura da variabilidade sazonal das propriedades, esses trabalhos eram sempre realizados sob a condição de Sizígia, durante um ciclo de completo de maré (13 horas). Os parâmetros hidrodinâmicos se mostraram fortemente dependentes das condições meteorológicas, foi claramente percebida a influência das águas continentais, através do rio Itapocu, nos episódios de chuvas mais intensas. Nesses casos devido o aumento da vazão fluvial e diluição das águas marinhas, por vezes não pode ser percebida uma estratificação da coluna d'água. O mesmo pode ser notado nas condições de menor intensidade das chuvas, só que nesse caso há um predomínio das águas marinhas ao longo da coluna. As correntes na desembocadura do sistema foram de baixa intensidade e mostraram a multiplicidade das forças naquela área, revelando um padrão irregular no seu sentido em algumas das campanhas amostrais.
The present essay tries to show some understanding of the processes of the flow and the mixture on the Itapocu Lagoon-Estuary System, between the cities of Barra Velha and Balneário Barra do Sul. The research shows the understanding of those processes having as objectives the determination of the main physics-chemical features of the water column, having as references the saltiness, temperature, turbidity, diluted oxigen and pH. Besides these features, an investigation about the standard of the stream flowing near the mouth of the Itapocu Lagoon-estuary System was realized, the acquisition of these data was straightened due to the use of a ADCP, which realizes a perfilation identifying the directions and the speed of the streams. The showing strategy was defined contemplating four sampling campaigns, one in each season of the year, so that a sample of the season of the variability of the properties was obtained, these works were always realized under the Sizígia condition, during a complete tide cycle (13 hours). The hidrodinamical parameters showed themselves strongly dependent on the weather forecast conditions, the influence of the continental Waters were clearly realized, throughout Itapocu river, on the more intense raining episodes. In these cases due to the rising of the water flow and the diluition of the sea waters, a stratification of the water column sometimes cannot be realized. The same cannot be noticed on the conditions of minor raining intensity, but in this case there is a predominance of sea Waters along the column. The streams on the mouth of the system have been the ones of low intensity and have shown the multiplicity of the forces in that area, revealing an irregular standard in its way in some of the sampling campaigns.
Cordier, Mateo. "Ecosystème estuarien et système économique régional: faisabilité d'une intégration par modélisation input-output : application au cas de l'habitat halieutique dans l'estuaire de la Seine." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209905.
Full textDoctorat en Sciences agronomiques et ingénierie biologique
info:eu-repo/semantics/nonPublished
Voltz, Baptiste. "Dynamique de la matière organique au sein dans les estuaires picards : caractérisation des faciès biosédimentaires et quantification des processus de minéralisation benthique." Thesis, Littoral, 2020. http://www.theses.fr/2020DUNK0579.
Full textEstuaries ensure a high production and transfer a large amount of organic matter (OM) from continent to ocean. To understand OM exchanges at the continent-ocean interface along the eastern English Channel coast, it is primordial to establish a mass balance OM budget in the three main estuaries : the Canche, the Authie and the Somme estuaries. In this frame, the sedimentary OM distribution and origin were studied by coupling a sedimentological description of surficial sediments and an elemental and isotopic characterization of the sedimentary OM. Such approach was carried out from near from subtidal to supratidal stages, along transects transversal to the main river channel, resulting in a sampling of 36, 37 and 39 stations respectively from the Canche, the Authie and the Somme estuaries. Based on this mapping approach, a representative transect was selected in the Canche and the Authie estuaries in order to quantify the sedimentary OM benthic mineralization along the tidal gradient and finally to establish an OM mineralization budget at the estuarine scale. Based on the sedimentological and biological characterization of sediments, the estuarine landscape was described according to four biosedimentary facies : sand flats, mud flats, low and high marshes. This study evidenced that the distribution of OM at the estuary scale is mainly controlled by the distribution of these biosedimentary facies. Indeed, sand flats are subject to intense hydrodynamic conditions in which sedimentary OM deposition is limited. On the other hand, OM is preferentially deposited in fine-grained sediments such as mud flats and salt marshes. Both of these sedimentary environments are subjected to lower hydrodynamic conditions, especially salt marshes, where vegetation enhances deposition and limits the resuspension of sedimentary OM. Indeed, the high quantities of sedimentary OM measured in salt marshes mainly originate from C3 halophytes dominating high marsh areas. Nevertheless, our study also evidenced that the deposition of sedimentary OM along the tidal gradient depends on the contribution of particulate OM from fluvial and marine/estuarine phytoplankton communities. Moreover, this study has demonstrated that various evolutions of the geomorphological features, with a mature salt marsh present in the Cancheestuary, a seaward prograding salt marsh on the north shore of the Authie estuary, a salt marsh retreat on the north shore of the Somme estuary resulting from an advanced sand infilling. The OM benthic mineralization campaigns demonstrated that during immersion and emersion periods, mud flats and salt marshes are the main contributors to total OM mineralization along the tidal gradient in contrast to sand flats. The spatial variation mainly depended on the sedimentological characteristics of each of biosedimentary facies but also on biological factors such as benthic macrofauna, microphytobenthos and root system of halophytes. The OM mineralization budget at the estuarine scale showed a significant contribution of sand flats in the Authie estuary given their wide distribution. This thesis contributes to a better definition of the role of "Picard" estuaries in the OM cycling and allows a first step towards the quantification of a mass balance OM budget in the three main estuaries of the eastern English Channel coast
Roets, Adriaan. "A preliminary analysis of the sediment budget across the Swartvlei estuary mouth." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95958.
Full textENGLISH ABSTRACT: The Swartvlei estuary and lake system is situated on the southern coast of the Western Cape Province of South Africa and forms part of the core conservation area of the Wilderness National Park. The Swartvlei system comprises two interlinked water bodies, namely Swartvlei Lake and Swartvlei estuary. SANParks have been monitoring this estuary closely over the past two decades, due to its importance to the ecology and to tourism. There are also low-lying properties on the perimeter of the Swartvlei estuary which run the risk of occasional flooding. Two of the major monitoring issues in this estuary system are the water level required for successful mouth breaching, and the influence of the water level on the low-lying properties. This study presents a preliminary analysis of the sediment budget across the Swartvlei estuary mouth. The objective of this study was to identify the various sediment contributory factors and to estimate the quantities that each individually contributed towards the defined sediment budget.
AFRIKAANSE OPSOMMING: Die Swartvlei meer en see monding is geleë aan die kaapse suidkus van Suid- Afrika. Dit vorm deel van die kern bewarings area van die Wilderness Nationale Park. Die Swartvlei sisteem bestaan uit twee verbinde, kern dele nl: Swartvlei meer en estuarium. Vir die afgelope twee dekades is hierdie area onder die noue toesig van SANParke as gevolg van die belangrikheid van die area met betrekking tot toerisme en ekologie. Daar is ook menigde laag liggende eiendomme aan die oewers, wat baie sensitief is vir watervlak stygings. Die optimum water vlakke benodig vir die uitskuring van die gety monding het ook implikasies vir die laag liggende eiendome en vereis noukeurige monitering. ‘n Voorlopige analise van die sediment begroting rondom die gety monding word deur hierdie studie voorgelê.
Raineault, Nicole A. "Effects of bulkheads on estuarine beach swash zone processes and characteristics." 2008. http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17376.
Full textGarcia, Tigreros Fenix. "The Combined Effect of Ocean Acidification and Euthrophication on water pH and Aragonite Saturation State in the Northern Gulf of Mexico." Thesis, 2013. http://hdl.handle.net/1969.1/149421.
Full textRubio, Zuazo Ana Maria. "Environmental influences on the sustainable production of the Sydney rock oyster Saccostrea glomerata : a study in two southeastern Australian estuaries." Phd thesis, 2007. http://hdl.handle.net/1885/49349.
Full textYang, Wen-Bin, and 楊文彬. "Investigation on the Characteristics of GHGs Emitted from Industrial Wastewater Treatment Processes and Natural Estuarine Wetlands by In-situ Continuous Monitoring Technology." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/x85k75.
Full text國立中山大學
環境工程研究所
106
In the context of global warming and climate change, greenhouse gas (GHG) emission has received a considerable attention for the past decades. Of many natural GHG sources, wetland plays an important role in modulating the concentrations of GHGs in the atmosphere. This study aims to continuously monitor the emission of greenhouse gases (CO2, CH4, and N2O) from a constructed wetland. A self-designed dynamic floating chamber was applied to collect GHGs through a Teflon tube connected to the top of the chamber, and in-situ monitored the concentrations of GHGs with a non-dispersive infrared (NDIR) monitor to continuously measure GHG emissions, estimated its CO2 equivalent (CO2-e), and investigated the seasonal variation of GHGs. This study further correlated GHGs and water quality, and combined GHG data and net primary production data to understand GHG emission from a natural estuarine wetland and a wastewater treatment plant. The temporal variation of greenhouse gas (GHG) emission from petrochemical and integrated industry wastewater treatment plants (WWTP) was then investigated. Two approaches including an in-situ continuous monitoring and a typical grab sampling methods were further compared. The in-situ continuous monitoring method provided more detailed information regarding the temporal variation of GHG concentration. A sufficient sampling frequency (e.g., once every 6 hours) for the grab sampling method is required to effectively resolve the diurnal variation of GHG emission. This study highlights significant diurnal variation of GHG concentration in different wastewater treatment units. Only with proper and reliable sampling and analytical methods, it becomes possible to correctly identify the characteristics of GHG emissions and to develop strategies to curtail the GHG emissions from such an important source in response to regulatory measures and international treaties. This study revealed that N2O was the dominant species responsible for GHG emissions from the WWTPs and the emission factors of CH4, and N2O were higher in the equalization tank and final sedimentation tank compared to other units. We also compared the GHG emission factors of this study with other literatures, showing that the GHG emission factors were much lower than those measured in Netherlands, Australia, and IPCC, but similar to those measured in Japan. Wetland play a crucial role in modulating atmospheric concentrations of greenhouse gases (GHGs). Key factors controlling GHG emission from subtropical estuarine wetlands were investigated in this study, which continuously monitored the uptake/emission of GHGs by/from a subtropical estuarine wetland located in the Minjiang and Zhangjiang estuaries in the coastal region of southeastern China. A self-designed floating chamber was used to collect air samples on-site at three environmental habitats (P. australis, mangrove, mudflats, and river water). Based on its potential to increase global warming, N2O was the main contributor to the total GHG emission, with that emitted from the river water being the most considerable. Tidal water carried onto the marsh had its own GHG content and thus may act as a source or sink of GHGs. However, water quality had a large effect on GHG emissions from the riverwater whereas the tidal water height did not. Both high salinity and large amounts of sulfates in the wetlands explicitly inhibited the activity of CH4-producing bacteria, particularly at nighttime. This study also investigated the seasonal variation of GHG emissions and estimated their overall CO2 equivalent (CO2-e). The GHG emissions were further correlated with water quality to identify which water quality parameters dominated GHG emissions in an estuarine mangrove ecosystem. A positive correlation was found between CO2 emission and water temperature, dissolved oxygen (DO), and total phosphorus (TP) in the riverwater. CH4 emission was positively correlated with TP, DO, and NH4+-N, while N2O emission was significantly positively correlated with DO, TP, and total nitrogen (TN) in the riverwater.