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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Qualidade da água do Canal São Gonçalo - RS/ Brasil: uma avaliação hidroquímica considerando seus usos múltiplos / Water quality of the São Gonçalo ChannelRS/Brazil: an hydrochemical evaluation considering its multiple uses

Souza, Mariana Farias de 26 February 2015 (has links)
Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2016-05-06T19:32:41Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) QUALIDADE DA ÁGUA DO CANAL SÃO GONÇALO-RS-BRASIL – UMA AVALIAÇÃO HIDROQUÍMICA CONSIDERANDO SEUS USOS MÚLTIPLOS.pdf: 2559551 bytes, checksum: e392f8cb31107f23bfcb83085ef642a1 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-05-09T17:32:25Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) QUALIDADE DA ÁGUA DO CANAL SÃO GONÇALO-RS-BRASIL – UMA AVALIAÇÃO HIDROQUÍMICA CONSIDERANDO SEUS USOS MÚLTIPLOS.pdf: 2559551 bytes, checksum: e392f8cb31107f23bfcb83085ef642a1 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-05-09T17:32:52Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) QUALIDADE DA ÁGUA DO CANAL SÃO GONÇALO-RS-BRASIL – UMA AVALIAÇÃO HIDROQUÍMICA CONSIDERANDO SEUS USOS MÚLTIPLOS.pdf: 2559551 bytes, checksum: e392f8cb31107f23bfcb83085ef642a1 (MD5) / Made available in DSpace on 2016-05-09T17:33:06Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) QUALIDADE DA ÁGUA DO CANAL SÃO GONÇALO-RS-BRASIL – UMA AVALIAÇÃO HIDROQUÍMICA CONSIDERANDO SEUS USOS MÚLTIPLOS.pdf: 2559551 bytes, checksum: e392f8cb31107f23bfcb83085ef642a1 (MD5) Previous issue date: 2015-02-26 / Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul - FAPERGS / O Canal São Gonçalo está situado na Bacia Hidrográfica da Lagoa Mirim e faz a ligação entre a Laguna dos Patos e a Lagoa Mirim. É um manancial hídrico com significativa importância econômica e ambiental para a região sul do Brasil e suas águas são utilizadas para diversos fins, como abastecimento público, pesca, navegação e irrigação. O objetivo desse trabalho foi avaliar a qualidade físico-química e microbiológica do Canal São Gonçalo, considerando variações espaciais e pluviométricas. Foram realizadas duas campanhas de amostragem, em período de baixa e de alta pluviosidade. Foram coletadas amostras de água em 22 pontos ao longo do canal e determinados 24 parâmetros físico-químicos e microbiológicos, sendo eles: pH, condutividade elétrica, turbidez, oxigênio dissolvido, temperatura, salinidade, sólidos dissolvidos totais, fluoreto, potássio, cálcio, cloreto, nitrato, transparência, coliformes totais, coliformes termotolerantes, cor verdadeira, cor aparente, sulfato, fosfato, amônia, nitrito, ferro, zinco e cromo VI. Os resultados encontrados para cada parâmetro foram comparados com a classe 2 da Resolução CONAMA n° 357/2005. Foi realizada a análise estatística dos dados através da utilização da técnica de Análise de Componentes Principais como forma a determinar quais os principais parâmetros responsáveis pela qualidade da água do canal e identificar quais os tributários mais significativos com aporte de poluentes para o manancial em estudo. Foi verificado que a qualidade da água do Canal São Gonçalo varia tanto espacial quanto temporalmente. A variação espacial da qualidade da água demonstrou estar diretamente relacionada à condição de seus afluentes e verificou-se que muitos destes afluentes contribuem para degradação da qualidade da água do Canal São Gonçalo. Verificou-se que no período de baixa pluviosidade os parâmetros relacionados aos sólidos dissolvidos na água são os que mais contribuem para deterioração da qualidade da água. Já no período de alta pluviosidade há um aumento significativo na parcela de sólidos suspensos, relacionados a diversos outros parâmetros. Conclui-se que a qualidade da água do Canal São Gonçalo está em desacordo com seus atuais usos e que essa é uma situação que vem se agravando ao longo dos anos. Medidas de remediação devem ser tomadas para que os usos múltiplos do canal sejam garantidos. / The São Gonçalo Channel is localized at Mirim Lagoon Watershed and connects two lagoons in southern Brazil, the Mangueira Lagoon and Patos Lagoon. It has a significant importance to southern Brazil and the channel is used to several purposes, such as water supply, fishery, navigation and irrigation. The aim of this research was access the water quality of the São Gonçalo Channel. Water samples were collected in 22 sites in two different periods, in rainy season and in dry season. The water samples were analyzed for 24 different surface water parameters: pH, conductivity, turbidity, dissolved oxygen, temperature, salinity, total dissolved solids, fluoride, potassium, calcium, chloride, nitrate, transparency, total coliforms, fecal coliforms, true color, apparent color, sulfate, phosphate, ammonia, nitrite, iron, zinc and chromium VI. The results were compared with brazilian standards. The principal component analysis techniques also were applied for the results. The analysis showed that the water quality of the São Gonçalo Channel is different to each site and to each season. Different tributaries were identified that pollute the São Gonçalo Channel. The water quality parameters that are related with dissolved solids are the most significant in dry season. In rainy season there are increases in the parameters that are related with suspended solids. From this study it was concluded that the water quality of the São Gonçalo Channel is not according with current uses and the pollution is getting worse over the years. Remediation actions are necessary for maintained the multiple uses of the channel.
192

Impact de l'évolution des déchets d'une installation de stockage de déchets non dangereux sur l'environnement - Site d'étude : l'ISDND d'Etueffont (Territoire de Belfort - France) / Environnmental impact assessment of a municipal solid waste landfill : Experimental site : the Etuffont landfill ( Belfort Aera-France)

Grisey, Elise 26 June 2013 (has links)
Ce travail a pour objectif d’étudier l’impact d’une installation de stockage de déchets nondangereux sur l’eau souterraine. L’ISDND d’Étueffont (90) dont le mode d’exploitation associedes prétraitements mécanique et biologique (broyage et maturation aérobie) comporte un casiernon sécurisé ainsi qu’un casier étanche. La caractérisation des lixiviats sur 21 ans (1989-2010)montre une dégradation rapide des déchets. Un état de stabilisation est atteint en fin de suivi. Lesprétraitements ont permis d’accélérer la dégradation des déchets et de réduire le potentiel polluantde l’ISDND. Les lixiviats sont traités in situ par lagunage naturel. Bien que cette technique soitpeu répandue pour le traitement des lixiviats, elle offre pourtant des abattements significatifs (75-90 %) de la matière organique, des matières en suspension, de l’azote et du phosphore. Lesprécédentes études ayant démontré une contamination de l’eau souterraine par les lixiviats, unedélimitation du panache de contamination a été entreprise en combinant des prospectionsgéophysiques du secteur (tomographie de résistivité électrique) et des analyses physico-Chimiquesde l’eau. Les résultats montrent une infiltration des lixiviats à la base du casier non sécurisé ainsiqu’au travers de la géomembrane du casier sécurisé. Une légère infiltration des eaux de lagunagea aussi été observée au niveau des lagunes. Le panache a une étendue limitée et se concentreessentiellement sous la base de l’ISDND. L’ensemble des résultats a permis de cibler les zonescontaminées et de définir les paramètres physico-Chimiques à surveiller dans le cadre du suivipost-Exploitation auquel est soumise l’ISDND jusqu’en 2031. / The purpose of this work was to evaluate the impact of a landfill on groundwater quality.Municipal solid waste from the Etueffont landfill (Belfort area, France) was mechanically andbiologically treated (shredding and aerobic composting) before being disposed of in an unlinedarea and in a lined cell. The leachate characterization performed over a 21-Year period (1989-2010) showed a rapid degradation of waste. A steady state was reached at the end of themonitoring. Waste pretreatment enhanced the rate of biodegradation and reduced the pollutionpotential of the landfill. The leachate produced was treated on site in a natural lagooning. Whilelagooning is not a widespread practice for leachate treatment, significant removal (75-90 %) oforganic matter, suspended solids, nitrogen and phosphorus was observed. In previous studies,groundwater contamination was highlighted around the landfill. As a consequence, geophysicalinvestigations of the area by electrical resistivity tomography and physico-Chemical analyses wereconducted in order to delineate the contamination plume. The results showed leachate infiltrationinto the soil below the unlined part of the landfill and leakage through the watertightgeomembrane of the lined cell. Seepage of wastewater into the soil below the lagoons was alsoobserved. The extent of contamination plume was limited and was mostly limited to the landfillboundaries. The results of this work allowed to determine the location of the contaminated areasand helped to choose the appropriate physico-Chemical analytes of the post-Closure groundwatermonitoring program, which will be applied to the landfill until the end of 2031.
193

Distribution spatiale des kystes de résistance des Dinoflagellés au niveau du sédiment superficiel de la lagune de Bizerte : cas de l’espèce invasive Alexandrium pacificum R.W. Litaker, 2014 / Resting cyst distribution of Dinoflagellates in the surface sediment of Bizerte lagoon : The case of the invasive species Alexandrium pacificaum R.W, Litaker, 2014

Fartouna-Bellakhal, Mouna 15 November 2016 (has links)
Les rejets des eaux de ballast dans le port de Bizerte et les fermes conchylicoles installées au niveau de la lagune de Bizerte peuvent constituer des sources potentielles ayant un impact sur l’introduction des espèces de Dinoflagellés nuisibles, en particulier celles qui sont potentiellement toxiques telles que A. pacificum, A.pseudogonyaulax, A.minutum, A. affine et Polysphaeridium zoharyi, sans pour autant négliger le rôle des courants dans la distribution des kystes. L’étude du trafic maritime sur les 7 années précédant notre prospection a révélé que 14 % de la flotte qui accoste au port de Bizerte est en provenance de la voie maritime d’origine Pacifique. Afin d’identifier les espèces de Dinoflagellés produisant des kystes à l’origine des efflorescences potentiellement toxiques, un échantillonnage à grande échelle spatiale au niveau des sédiments superficiels a été effectué pour relever les densités des kystes en fonction des caractéristiques sédimentaires à savoir la teneur en eau, la matière organique, la granulométrie, l’abondance des formes végétatives ainsi que les facteurs environnementaux. Cette étude a permis l’identification de 48 morphotypes de kystes de Dinoflagellés, principalement dominés par Brigantidinium simplex, Votadinum spinosum, Alexandrium pacificum, Alexandrium pseudogonyaulax, et Lingulodinum machaerophorum. La densité des kystes a varié de 1276 à 20126 kystes g-1 sédiment sec. Des différences significatives portant sur la distribution des kystes ont été enregistrées, ce qui nous a permis de faire la distinction de deux zones dans la lagune de Bizerte. Un intérêt particulier a été porté au complexe Alexandrium tamarense dont fait partie l’espèce A. pacificum connue pour être à l’origine des efflorescences nuisibles (HABs). En outre, l’examen morphologique et le ribotypage des formes végétatives d’A. pacificum en provenance de cultures microalgales obtenues à partir de l’extraction, l’isolement des kystes de résistance en provenance du sédiment, et leur germination ont été réalisés pour l’obtention d’une culture cellulaire monospécifique ABZ1 qui se caractérise par un taux de croissance de µ= 0.33j-1 et un temps de génération T=2.1j. Le profil toxinique obtenu à partir d’un extrait de culture ABZ1, en phase exponentielle a révélé la présence de N-sulfocarbamoyl toxine C1 (9.82 pg toxin cell_1), la GTX6 (3.26 pg toxine cell_1) et la carbamoyl toxine Neo-STX (0.38 pg toxin cell_1), représentant 2,8% du total des toxines de cette souche. Une corrélation entre l’abondance des kystes d’Alexandrium pacificum et le pourcentage en eau ainsi que la matière organique a été relevée. Par ailleurs, la fraction sédimentaire <63µm s’est avérée potentiellement favorable à l’initiation des efflorescences du dinoflagellé Alexandrium pacificum au niveau de la lagune de Bizerte. Une différence significative dans le schéma de la distribution des kystes a été illustrée, mettant en évidence un zonage de la lagune avec une abondance plus importante au niveau des zones conchylicoles. / The ballast water discharges in Bizerte harbor and shellfish aquaculture farms in Bizerte lagoon can be potentials sources with an interest in the introduction of harmful species, especially those that are potentially toxic like A. pacificum, A. pseudogonyaulax, A.minutum, A.affine and Polysphaeridium zoharyi, without neglecting the role of currents in the distribution of cysts. The study of the vessel traffics for 7 years before our prospection in Bizerte harbour have showing that the percentage of vessels coming from the Pacific road is around 14%. In order to identify species of Dinoflagellates producing resting cysts incriminated on potentially toxic blooms, a high spatial resolution sampling of the surface sediment for the identification and counting of resistance cysts was carried out to estimate the cyst density based on sedimentary characteristics, water content, organic matter, granulometry, abundance of vegetative forms and environmental factors. This study allowed the identification of 48 morphotypes of dinoflagellate cysts, mainly dominated by Brigantidinium simplex, Votadinum spinosum, Alexandrium pacificum, Alexandrium pseudogonyaulax and Lingulodinum machaerophorum. The density of cysts ranged from 1276 to 20126 cysts g-1 dry sediment. Significant differences between cyst distributions were recorded, which enabled us to distinguish two areas in the Bizerte lagoon. Particular attention was given to the complex Alexandrium tamarense (HABs). In addition, morphological examination and ribotyping of vegetative cells obtained from microalgal cultures following extraction process, isolation of resistance cysts from sediment, and their germination led to the production of monospecific culture: ABZ1 characterized by a μ (growth rate) = 0.33 day-1 and a generation time T = 2.1 day. These reviews have confirmed the newly identified genus and species in the Mediterranean sea and mentioned specifically in the lagoon of Bizerte: Alexandrium pacificum. The toxin profile obtained from an extract of ABZ1 culture in exponential phase revealed the presence of N-sulfocarbamoyl toxin C1 (9.82 pg toxin Cell-1), the GTX6 (3.26 pg toxin Cell-1), carbamoyl and the Neo-STX toxin (0.38 pg cell toxin-1), representing 2.8% of total toxins of this strain.A correlation between the abundance of cysts of Alexandrium pacificum and water percentage well as organic matter was found. Moreover, sediment fraction <63μm proved potentially favorable to initiate Alexandrium pacificum blooms in Bizerte lagoon. A significant difference in the cyst distribution diagram was shown, highlighting a zoning of the lagoon with a greater abundance in shellfish farm areas.
194

Site selection and community participation in the development of Gracilaria Gracilts (stackhouse) steentoft, irvine and farnham mariculture in the Western Cape province, South Africa.

Brown, Bernadette January 1999 (has links)
Magister Artium (Development Studies) - MA(DVS) / The seaweed Gracilaria gracilis has been shown in previous studies to have potential for mariculture along the West Coast of South Africa. However, the selection of suitable sites is crucial for the success of a farming enterprise. The variables important in the success or sustainability of suspended raft culture, and the environmental factors influencing these variables, were identified through a literature review. A suitable site was defined as a site with surface water temperature of between 10 and 17 "C, water depth of between 2 and 10 m below surface, and wave heights of less than 4 m. Data and information about these factors were obtained from sources such as the Sea Fisheries Research Institute, the SADCO database, the CSIR and from volunteers in St Helena Bay. The objectives of this study were to convert available data into formats that could be used in a Geographical Information System (GIS), and to predict suitable and available sites for suspended cultivation of Gracilaria gracilis in Saldanha Bay, Langebaan Lagoon and St. Helena Bay. Data were converted to digital format and data layers created. Each data layer represented suitable and unsuitable areas. Areas with existing mariculture, harbours, ship traffic zones and other uses were excluded to determine the real available areas. The Saldanha Bay-Langebaan lagoon system and St Helena Bay, have sites that show potential for suspended cultivation of G. eracilis. The total sizes of the areas selected as suitable are 975.4 ha in Saldanha Bay and 474.8 ha in St. Helena Bay. Some sites predicted as suitable are located in areas known to be subject to conditions not suitable for seaweed mariculture, and led to the conclusion that the accuracy of input data or method of analysis must be improved.
195

The Molluscan Taphofacies of and Influence of Callianassid Shrimp on a Carbonate Lagoon (St. Croix, US Virgin Islands)

Lee, Rowan January 2019 (has links)
No description available.
196

VATTENLEVANDE FÅGLARS PÅVERKAN PÅ VEGETATIONEN I GRUNDA HAVSMILJÖER : FJÄRRANALYS SOM VERKTYG FÖR ATT IDENTIFIERA BETNINGSMÖNSTER / The effect of waterfowl on submerged aquatic vegetation in shallow bays : Remote sensing as a tool to identify grazing patterns

Gerland Fontana, Vanessa January 2023 (has links)
Submerged aquatic vegetation (SAV) is an important source of food for waterfowl. Effects of waterfowl grazing on SAV has foremost been studied in freshwater and agricultural ecosystems. This study used drone-based remote sensing to identify waterfowl grazing patterns and quantify the effect their grazing has on SAV in shallow coastal areas in Västerbotten County. Six subareas containing a total of 27 bays were studied in detail. Grazed areas were delimited by polygons in GIS. Using GIS, layers containing water depth, wave exposure and biotope were added to polygons and mean-values were calculated. Field data containing types of SAV were noted in grazed areas and compiled by number of observations. Data was tested in a regression analysis and a X2-test. Results revealed no connection between water depth and wave exposure in regard to the proportion of grazed area. Grazing was identified in 20 out 27 bays and in 41 out of 126 drone images. Field data containing charophytes often overlapped with polygons for grazed areas, but a more systematic collection of data is needed to conclude whether the presence of charophytes is crucial for the choice of grazing area. Shallow coastal areas can have a great variance in SAV species composition from year to year due to ice scraping during winter and yearly land raise. Continuous studies of these areas are therefore needed in order to conclude if changes in SAV species composition is due to abiotic factors or grazing from waterfowl.
197

Field-validated inter-comparison of Sentinel-2 MSI and Sentinel-3 OLCI images to assess waterquality in the Indian River Lagoon, Florida

Woodman, McKenzie Leonard 27 July 2023 (has links)
No description available.
198

Quantifying The Success Of Eastern Oyster Pilot Reefs In Brevard County, Florida

Anderson, Lacie 01 January 2016 (has links)
Crassostrea virginica, the eastern oyster, is a native keystone species that inhabits many coastal and estuarine ecosystems along the Atlantic seaboard. Introduction of the eastern oyster into estuarine areas with limited current populations is gaining popularity as a pro-active approach to improve estuarine water quality. In November 2014 and April 2015, a total of five pilot oyster reef treatments were deployed in Brevard County: bagged adult oysters (grown by community members under their docks through oyster gardening) collected in fall 2014 and spring 2015, bagged clean shell, oyster restoration mats, and empty plots (control). Locations of deployment included a Merritt Island impoundment (Marsh Harbor), Nicol Park (Port St. John), and Scout Island (Melbourne Beach). Prior to deployment, we collected morphometric data (shell length, weight) on all gardened oysters. Abiotic factors including salinity, air and water temperature, and wind speed were collected monthly. During quarterly sampling at each site, morphometric data were collected for all live oysters, surviving and newly recruited. Results show survival of gardened oysters and natural recruitment differed by and depended greatly on the within-site location of each reef. In areas with no recruitment and limited gardened oyster survival, regular deployment of gardened oysters is needed for long term success. In areas with natural recruitment, bagged, clean shell or oyster restoration mats are most successful. Future restoration sites should be tested prior to any large-scale oyster deployments.
199

Interactions between the Indian River Lagoon blue crab fishery and the bottlenose dolphin Tursiops truncatus

Noke, Wendy D. 01 January 1999 (has links)
No description available.
200

The Ecological Dynamics of a Coastal Lagoon: A Study of the Morphodynamics, Land Use Change, Community Participation, and Spatial Planning of the Segara Anakan Lagoon in Indonesia

Nandi, Nandi 04 February 2015 (has links)
A coastal lagoon is a landform that is influenced by natural processes and human activities. All human activities at the upstream, particularly agriculture and cultivation bring soil, waste, and other materials to the downstream area through the river drains into the lagoon. Even though its position is inland of water bodies, the lagoon is still affected by waves and winds from the sea. Additionally, coastal lagoon will be the depository place for sedimentation from the upland area. Segara Anakan (SA), which is located in Indonesia, is an example of a coastal lagoon area, which has a unique biophysical characteristic. The region has a great natural ability to ensure the sustainability of the interrelationships between terrestrial, estuarine and marine ecosystems in harmony and balance as a habitat for flora and fauna. The region is an area of migration of various types of protected animals and it is a place of breeding for diverse species of the shrimp and fish, which have a highly economical value. Segara Anakan lagoon (SAL), currently experiencing acceleration narrowed on its area due to a very intensive sedimentation from the mainland. The research aims to answer the question of how ecological dynamic occurs in the SAL area due to sedimentation. Achieving the objectives of this study required examining the morphology and land use changes with multitemporal remote sensing approaches. While, to assess the role of community participation and planning management strategies is using qualitative descriptive methods and SWOT analyze. The using of multitemporal remote sensing Landsat images is possible to analyze the morphological and land use changes with different time and sensors. These Landsat has image accuracy about 92.66%. It can be used for image interpretations resulting 13 classes of land use. The morphodynamics of SAL indicated by the changes of area of lagoon and accreted land and also the distance of coastlines during the periods 1979-2013. In addition, the land use or land cover also changes during that time. The bigger portions of land use changes are in the tropical and mangrove\''s forests. There are distinctive forms of participation in conservation efforts. The upstream community involvement in conservation tends to be different participating in the way of ideas, money, materials, properties, skills and expertise or social activities. In addition, the community at downstream area has a sufficiently high level of participation in environmental conservation. There are also strong relationships between the level of education and level of income and basic knowledge in conservation with the participation of SA conservation. The ecological dynamics of the SAL area are described with a historical time line. It is divided into three time periods: the 1970s - 1980s, the 1990s and from 2000 onwards. Each of these has occurrences that can lead to changes in the environment. The implementation of appropriate conservation technique can reduce the sedimentation rate. Hence, the synergic coordination measures between upstream and downstream regions are necessary in the future. Increasing community awareness and participation in the conservation by improving educational sector, providing information, and applying sustainable development land use are the ways to match human activities with the temporal and spatial dynamics of the coastal resources.

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