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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.
211

Mangrove Morphological Change Across an Environmental Gradients: Implications for Competitive Ability in a Changing Climate

Unknown Date (has links)
In Florida, mangroves have responded to climate change by slowly migrating northward into traditional salt marsh habitat. However, little is understood about the relationships among mangrove growth form plasticity and environmental conditions. In addition, the effects of the mangrove northward expansion on pre-existing salt marsh communities are unknown, especially any influences of differences in tree morphology. The size, canopy structure, and root structure of the three mangrove species Rhizophora mangle, Avicennia germinans, and Laguncularia racemosa were measured at six sites along the east coast of Florida. Structural equation modeling was used to evaluate the multivariate relationships between environmental and biotic variables. Mangrove growth form varied widely with environmental variables. The results of this study suggest that R. mangle expansion into salt marsh may rely on interactions with salt marsh and shading as well as on climatic variables, which has implications for future mangrove expansion northward in Florida. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
212

Análise da evolução da ocupação urbana na faixa oceânica do município de Santa Vitória do Palmar/RS: balneários do Hermenegildo e da Barra do Chuí

Silva, Cristiano da January 2017 (has links)
As zonas costeiras estão em constante processo de pressão, tanto pela ação humana, que acaba rompendo o equilíbrio dominante, como pela ação da natureza, que está ligada principalmente a fatores geológicos, fatores climáticos e à dinâmica costeira. Neste trabalho buscou-se analisar a evolução do processo de ocupação urbana na faixa oceânica no município de Santa Vitória do Palmar, nos balneários do Hermenegildo e da Barra do Chuí, devido ao fato de esse local apresentar problemas em seu processo de urbanização, que se configuram pela falta de planejamento e de ordenamento territorial. Para essa análise, utilizou-se produtos de sensoriamento remoto em escala multitemporal, com perspectivas temporais em que se pode trabalhar e entender as rupturas de paradigmas em diferentes momentos históricos. Para isso, foram feitas análises em um levantamento aerofotogramétrico, adquirido pelo Exército Brasileiro, na Escala 1:75.000 do ano de 1964, análises em Imagens de Satélite Landsat TM7, do ano de 1996 e Imagens de Satélite QuickBird do ano de 2010. Portanto, esse trabalho propôs uma análise em escala multitemporal no processo de urbanização dos balneários do Hermenegildo e da Barra do Chuí, para um melhor entendimento do porquê dos problemas com as construções residenciais na faixa frontal ao Oceano Atlântico, que tem levando muitos moradores a perda total de suas residências. Verificou-se que a evolução dos percentuais de ocupação urbana nos balneários do Hermenegildo e da Barra do Chuí foi bastante significativa, sendo o que os dois balneários apresentaram crescimento mais elevado nas três primeiras décadas analisadas e ainda concluiu-se que no último intervalo da análise os índices de crescimento urbano foram menores para os dois balneários, recomendando-se maiores estudos e monitoramento dos vetores de crescimento urbano para ambos os balneários, com maior atenção para o balneário do Hermenegildo, devido ao grave problema de erosão costeira. / Coastal zones are constantly affected by the pressure process, caused by the human action, which ends up breaking the dominant balance, as well as by the action of the nature, which is mainly related to geologic and climatic factors and to the coastal dynamic. This study aims to analyze the urban occupation evolution process along Santa Vitória do Palmar coastline, especially Balneário do Hermenegildo and Balneário da Barra do Chuí, considering the fact that this specific territory presents lots of problems concerning its urbanization process. For this analysis, images captured by remote sensing were used in a multitemporal scale, trough time perspectives that enable this study to develop and understand the paradigmatic ruptures in different historical periods. In order to do so, different types of images were analyzed, such as the aerial photogrammetric survey, taken by the Brazilian Army, in the 1:75.000 scale of 1964, TM7 Landsat Satellite Images, taken in 1996, and QuickBird Satellite Images, taken in 2010. Therefore, this study promoted an analysis in a multitemporal scale of the urbanization process regarding the territory already mentioned, in order to discover the causes of the problems involving residential constructions located on the frontal area of the Atlantic Ocean, which might be the reason why the residents are totally losing their residences. It was found that the development of the urban occupation percentage in Balneário do Hermenegildo and Balneário da Barra do Chuí was very significant, based upon the fact that both beaches present a notorious increase on the first three analyzed decades and, beyond that, it was concluded that during the last interval of the analysis, the urban growth indices were lower for both, suggesting that this field demands more studies and monitoring of the urban growth vectors for both beaches, attaching particular attention to Balneário do Hermenegildo because of its severe coastal erosion problem.
213

Les plages entre altération physique et représentations, les pratiques de réaménagement et résilience : l'exemple des plages du golfe du Lion (Vias, Agde et Marseillan) / Beaches between physical alteration and representations, redevelopment practices and resilience : the example of Gulf of Lion beaches (Vias, Agde and Marseillan)

Bahroun, Soumaya 25 June 2018 (has links)
La question de la remontée des niveaux marins et du recul du trait de côte est aujourd'hui une préoccupation de premier ordre face à laquelle les sociétés sont en attente de connaissances et de propositions. Or, les littoraux les plus menacés, les côtes basses, sont d'une part le siège de pratiques séculaires, de "défense contre la mer" et ont, d’autre part, été investis dans une période récente par des activités touristiques tournées vers l'exploitation des plages. Cette vulnérabilité physique et sociale explique notre choix pour les littoraux correspondants aux trois communes de Vias, Agde et Marseillan (golfe du Lion). Ces terrains réunissent un ensemble de caractéristiques qui en font un terrain laboratoire propice à l’observation et au traitement de cette problématique. L’érosion et la submersion marine ont marqué l’espace et les paysages de ces territoires. Face à cette situation de vulnérabilité se pose la question de l'adaptation des systèmes socio-économiques qui se sont développés dans ces espaces et de la résilience des territoires. La résilience désigne la capacité à anticiper, à réagir et à rebondir après un événement perturbateur. Cette approche nous permet de comprendre comment la société locale réagit face à des situations de vulnérabilité et comment se construisent les capacités d’adaptation et de résilience dans sa dimension territoriale. L’approche monographique est mobilisée dans notre travail à partir des entretiens semi-directifs, l’objectif est de confronter la notion théorique de la résilience des territoires à sa réalité pratique. À travers, ces trois territoires, il s’agit d’apporter des connaissances empiriques afin de décrypter les enjeux et révéler un modèle de développement axé sur la littoralisation des activités. Nous proposons à la fin de ce travail une nouvelle démarche, la Résilience Intégrée de Zones Côtières (RIZC), pour dépasser la complexité du réel et entretenir les solidarités entre tous les acteurs concernés. La RIZC permet de maintenir un niveau d’activité à l’aide des capacités de la souplesse du système afin de limiter les conflits d’intérêts entre public et privé et renforcer leur confiance mutuelle. / Rising sea levels and coastline recession have become a major issue about which society requires knowledges and solutions. The shorelines most threatened are low seacoasts which are both places of century-old traditions of coastal protection and localities exploited for tourism attracted by their beaches. This material and social vulnerability explains our choice of three municipalities: Vias, Agde and Marseillan (France, Gulf of Lion). These cases highlight features that permit pertinent observations on the subject. Erosion and coastal flood have shaped their landscape and planning. Can socioeconomics systems adapt to this new vulnerability? Resilience is the capacity to anticipate, react and bounce back after a disturbance. This approach allows us to understand how local communities react to vulnerability and plan new forms of resilience and adaptation. We use semi-structured interviews to build monographs and contrast theoretical resilience against real life experiences. These three territories are used to gather empirical knowledge in order to clarify the issues at stake and the need to abandon the concentration of activities on shorelines. Finally, we discuss how a new approach known as integrated coastal zone management; can overcome the complexity of the real situations encountered and underpin solidarity between all the stakeholders. Using a more versatile system, integrated coastal zone management, can help to maintain activities, limit conflicts of interest between public and private stakeholders and strengthen their mutual trust.
214

The ecological and economic analysis of beach management strategies in Scotland

Griffin, Caroline January 2016 (has links)
Coastlines are particularly susceptible to the necessary trade-offs which occur between different ecosystem services. Should the areas be managed for biodiversity or for people? Where sandy beaches are found there is usually a management decision to be made between managing for recreation or for biodiversity. Many popular tourist beaches (particularly those with a Beach Award) are often groomed with mechanical equipment to remove any stranded seaweed and associated litter which can get entangled in the wrack. This is likely to be having a negative impact on coastal biodiversity, with wide ranging implications for the entire habitat, including the intertidal zone, sand dunes and shorebirds. Beached wrack should be allowed to naturally decompose providing a habitat for numerous species of macro-invertebrates. These macro-invertebrate communities not only include many endemic species found exclusively along the strandline but they also provide a very rich source of food for shorebirds. The re-mineralised nutrients resulting from the decomposed macrophytes should then become available to provide a rich source of nutrients to dune, strandline and marine ecosystems populations of the strandline. In previous studies grooming has been shown to have a negative impact on the invertebrates of the strandline and this study reveals that tidal range has an effect on the impacts of grooming with a higher tidal range having a more negative impact on the invertebrates. A study to observe the impacts of grooming on both adult plant and seed bank communities of the sand dunes found that grooming is having a negative impact on these populations. Grooming is predominantly driven by beach managers who aspire to gain Beach Awards in order to attract tourists to their beaches. Using non-market valuation in the form of a stated preference choice experiment and a travel cost model, it was observed that Beach Awards are not valued by beach goers but are instead influenced to visit a particular beach by good bathing water quality, high levels of biodiversity and low levels of litter. It was also shown that stranded seaweed on the beach does not deter visitors. Future management suggestions include attempting to reduce the confusion arising from the presence of multiple beach awards by either removing them altogether or by making their criteria more clear and direct with consistency in their design and designation. Bathing water quality should be completely removed from the Beach Award system and real-time information in the form of electronic signage and a publicly available App should replace it.
215

Reconstitution paléogéographique et prospection archéologique en zone littorale par approches géophysiques multi-méthodes et multi-échelles / Paleo-geographical reconstitution and archaeological survey in coastal area by multi-method and multi-scale geophysical approaches

Bruniaux, Guillaume 07 December 2017 (has links)
L’étude archéologique d’un site est réalisée sur la base d’une fouille, qui est une étude précise sur une ouverture restreinte. En amont de cette opération, la prospection géophysique offre la possibilité de localiser une zone susceptible d’apporter des informations majeures par une cartographie détaillée du site. Ces travaux de thèse se focalisent sur un protocole original de prospection magnétique pour détecter des structures pluri-métriques à pluri-décimétriques et une démarche méthodologique pour estimer la conservation d’un niveau d’occupation archéologique. Ces développements ont été réalisés pour apporter un maximum d’information sur l’occupation anthropique et cibler une zone de fouille suivant la problématique archéologique associée au site. Dans les zones littorales et suivant la période chronologique considérée, l’environnement associé à une occupation était différent. La modification relativement rapide des environnements côtiers résulte de la remontée du niveau marin depuis la fin du dernier maximum glaciaire. Dans le cadre d'une étude paléoenvironnementale associée à un site, l’objectif de la prospection géophysique est similaire à celle effectuée pour une fouille : localiser une zone d’implantation des carottages paléoenvironnementaux. La démarche méthodologique développée dans ces travaux est basée sur une approche paléogéographique de l’environnement à partir de prospections géophysiques multi-méthodes et multi-échelles. Des prospections électromagnétiques (Slingram), des sections électriques et des diagraphies électriques (direct-push) apportent une représentation cartographique et stratigraphique des contrastes géophysiques de la subsurface. Deux zones d’étude ont été sélectionnées pour tester et mettre en place ces démarches méthodologiques, le site néolithique du Pontet (Charente-Maritime) et les ports antiques de Narbonne. Ces deux sites sont dans des contextes archéologiques, géographiques et géologiques différents. / Archaeological study of a site is based on an excavation which is a comprehensive study on a restricted gap. Before excavation, geophysical survey supplies the possibility to locate an area likely to provide details by detailed mapping of the site. This PhD work focus on an original magnetic survey protocol to detect pluri-metric and pluri-decimetric structures and a methodological approach to estimate the conservation of an archaeological level occupation. These developments have provided maximum information on anthropogenic settlement and to target excavation zone according to the archaeological problem of the site. In coastal zones and according to the considered chronological period, the environment of the settlement was different. The relatively rapid change in coastal environments results from the rise of sea level since the end of the last glacial maximum. As part of a paleoenvironmental study of a site, the objective of geophysical survey is similar to that for excavation : locating an area to paleoenvironmental coring. The methodological approach developed in this work is based on a paleogeographic approach to the site environment using multi-method and multi-scale geophysical surveys. Electromagnetic survey (Slingram), electrical tomography and direct-push electrical resistivity logging provide a cartographic and stratigraphic representation of the geophysical contrasts of the subsurface. Two study areas were selected to test and implement these methodological approaches, the Neolithic site of Le Pontet (Charente-Maritime) and the ancient harbours of Narbonne. These two sites are in different archaeological, geographical and geological contexts.
216

CaracterizaÃÃo dos tabuleiros prÃ-litorÃneos do Estado do Cearà / Characterization of pre-boards the coastal State of CearÃ

Luiz Josà Cruz Bezerra 17 April 2009 (has links)
A zona costeira cearense tem aproximadamente 600 km de extensÃo, distribuÃda em diversas unidades geoambientais. O foco deste trabalho sÃo os Tabuleiros PrÃ-LitorÃneos, moldados em rochas da FormaÃÃo Barreiras, de Paleodunas e Dunas. O plano amostral à composto de 71 poÃos rasos totalizando 360 amostras distribuÃdas por toda zona de Tabuleiros. Por intermÃdio de anÃlises granulomÃtricas, teor de carbonato, morfoscopia, geomorfologia por sensoriamento remoto e determinaÃÃo dos teores de metais em 9. Pelos parÃmetros analisados foi descoberto que a zona de dunas costeiras (paleodunas) nÃo se limita somente aos grandes campos de toda a Ãrea e com forma definida, sendo encontrados em locais antes mapeados como da FormaÃÃo Barreiras. Em geral, as paleodunas se encontram logo abaixo das recentes tendo as mesmas caracterÃsticas. A estratigrafia destes depÃsitos à formada no topo por uma camada bem fina de solo ou por sedimentos provenientes de rios, quando prÃximos ou na abrangÃncia de suas planÃcies de inundaÃÃo. Sotopostos, os sedimentos da FormaÃÃo Barreiras, sendo uma das principais feiÃÃes caracterÃsticas dos Tabuleiros PrÃ-LitorÃneos com granulometria variando de areia mÃdia a fina, com a presenÃa de nÃveis arenoargilosos e conglomerÃticos. O tom predominante à o avermelhado, que vai clareando ao se aproximar do nÃvel freÃtico. A partir de imagens Landsat ETM+ e SRTM, onze perfis topogrÃficos foram traÃados, identificando o comportamento dos Tabuleiros e sua delimitaÃÃo, com Ãnfase as drenagens que recorta a unidade. Os teores de metais presentes nos sedimentos apresentam ordem de abundÃncia Al>Fe>Pb>Mn>Cu, o alumÃnio à mais abundante com teor mÃdio de 5,47 mg.g-1, seguido do ferro, com 1,93 mg.g-1, chumbo com 4,58 ug.g-1, manganÃs com 4,14 ug.g-1 e o cobre, com 0,11 ug.g-1. O alumÃnio à derivado do intemperismo das rochas do embasamento, o ferro de um grupo de minerais que compÃe o embasamento, o chumbo tambÃm à encontrado nas rochas em regiÃes mais interiores, contudo a explicaÃÃo pra seus teores à a urbanizaÃÃo na regiÃo, o manganÃs e o cobre estÃo na ordem de ug.g-1 sua concentraÃÃes muito baixas tem explicaÃÃo na deficiÃncia deste elementos no embasamento. A quantidade mÃdia de matÃria orgÃnica nÃo excedeu 1,17%, e 2.42 % para carbonato de cÃlcio. / The coastal area Cearà has approximately 600 km long, divided into several units geoambientais. The focus of this work are the Pre-coastal trays, molded in the Barreiras Formation rocks of Paleodunas and dunes. The sampling plan consists of 71 shallow wells total of 360 samples distributed throughout the Tablelands area. Through analysis of size, content of carbonate, morfoscopia, geomorphology and remote sensing for determining the levels of metals in the 9th By the parameters analyzed was discovered that the area of coastal dunes (paleodunas) is not limited only to major fields of the whole area and shape, before being found in local map and the Barreiras Formation. In general, the paleodunas are below the recent having the same characteristics. The stratigraphy of these deposits is formed on top and a thin layer of soil or sediment from rivers, or when coming in from their coverage of flood plains. Sotopostos, the sediments of the Barreiras Formation, one of the main features characteristic of pre-coastal trays with a range of medium to fine sand, with the presence of arenoargilosos levels and Conglomerates. The predominant tone is reddish, which will clear when approaching the water table level. The images from Landsat ETM + and Srtm eleven topographic profiles were traced, identifying the behavior of the trays and their boundaries, emphasizing the drainages that cut the unit. The levels of metals in sediments have plenty of order Al> Fe> Pb> Mn> Cu, aluminum is more abundant with average content of 5.47 mg.g-1, followed by iron, with 1.93 mg.g -1, lead ug.g-1 to 4.58, manganese 4.14 to ug.g-1 and copper, with 0.11 ug.g-1. Aluminum is derived from the weathering of rocks of the basement, the iron of a group of minerals that make up the rock, lead is also found on rocks in the more inland, though the explanation for its content is the urbanization in the region, manganese and copper are the order of ug.g-1 is its very low concentrations in the explanation of this deficiency in the light elements. The average quantity of organic matter did not exceed 1.17% and 2.42% for calcium carbonate.
217

Diagnóstico sócio-ambiental do Balneário Cassino e áreas adjacentes - Rio Grande-RS : subsídio ao gerenciamento costeiro integrado local

Sarilho, Karina Aparecida January 2003 (has links)
As preocupações com a integridade e o equilíbrio ambiental das regiões costeiras decorrem do fato de serem as mais ameaçadas do planeta, justamente por representarem para as sociedades humanas um elo de ligação e de intensa troca de mercadorias entre si, com a exploração desordenada e muitas vezes predatória de seus recursos naturais, tornado-se, já na era industrial o principal local de lazer, turismo ou moradia de grandes massas de populações urbanos. A vocação de uso de determinada paisagem esta relacionada às funções que a mesma desempenha. O que ocorre é que o padrão de desenvolvimento adotado e a atual configuração sócio-econômica determinam usos que nem sempre coincidem com a sua melhor utilização. A fim de subsidiar futuros planos de uso e ocupação racional do solo das áreas naturais adjacentes ao Balneário Cassino (Rio Grande, RS), de acordo com os preceitos do Gerenciamento Costeiro Integrado, desenvolveu-se um Dianóstico Sócio-Ambiental da área dentro de abordagem sistêmica. Foram considerados principais componentes e processos urbanos e ambientais, definidos a partir da interpretação de aerofotografias, levantamentos de campo quali-quantitativos e informações bibliográficas. Os resultados são apresentados na forma de tabelas, quadros, levantamentos fotográficos, modelos diagramáticos conceituais, e mapas temáticos, que permitiram entender a organização estrutural e funcional da paisagem, e fundamentar uma ordenação espacial dos usos desta área, de modo a adequá-los às suas especificidades ambientais, histórico-culturais, sócio-econômicas e legais. / The integrity and the environmental equilibrium of coastal zones are increasingly becoming a concern to environmental scientists. Coastal environments are one of the most threatened in the world. Besides, they represent, to the human societies, a link of connection and intense exchange of merchandise amongst each other, with disordered and, at many times, predatory exploration, becoming, already at the industrial age, a main site of leisure, tourism and habitation of large masses of urban population. The vocation of a determined landscape is related to the functions and roles it plays. What actually occurs is that the development pattern adopted and the actual socio-economics determine the uses, which not always coincide with its best utilization. In order to assist future plans of rational use and occupation of natural areas adjacent to Cassino's Bathing Resort (Rio Grande, RS), in agreement with the Integrated Coastal Zone Management, a social-environmental diagnosis of the study site was developed using the systemic approach. The main environmental and urban processes and components were considered. They were defined based on aerophotos interpretation, quail-quantitative field survey and bibliographic information. The results, presented in the form of tables, photographic surveys, conceptual diagrammatic models and thematic maps, allowed to understand the structural and functional organization of the landscape and to establish a spatial ordering of land use to adequate them to their environmental, historic-social, socioeconomics and legal specificities.
218

A produção do espaço: ausência de integração das políticas públicas na zona costeira do Município de Fortaleza-CE

Romcy, Cristina Maria Aleme 24 February 2010 (has links)
Made available in DSpace on 2016-03-15T19:24:26Z (GMT). No. of bitstreams: 1 Cristina Maria Aleme Romcy.pdf: 3757553 bytes, checksum: 6ee4c8042faef927b7a0303a9fcf2832 (MD5) Previous issue date: 2010-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The worldwide preoccupation with the activities developed in costal zones and their consequences takes many countries to develop studies in order to find solutions with partnerships. Within this band of ocean near the coast, actions and policies are applied without a cooperative guideline in the sense of depredating no natural existing resources and do not pollute. Many times there are occupations conflicting the use when it is installed an environmental degrading process. The causes of these problems are: the unknowing of the public goods and of their environmental resources, as well as the lack of integration among the governmental sectors and the society in the environmental management. This thesis general objectives structure a management style of coastal zone of Fortaleza, capital of Ceará. And for this, discussed the plans, programs and projects needed to administrate comprehensively the coastal zone, being implemented together with the municipalities, the state and the federal government, aiming to propitiate conditions to develop sustainable projects of land use and occupation, in order to contribute to the environment quality, by the nation. The methodology adopted is based on the documental analysis existing for the coastal zone, guided by the theoretic-conceptual references that treat the themes about the coastal zone, its management and its land use and occupation. Thus it begins with the knowledge of the space and its resources, problems and economic activities identification that cause pollution and environmental degrading. The analysis are developed focusing the existing public policies and the instruments for their application. The concept of coastal zone in focus treated the theoretical reference in a comprehensive form searching to indentify the bases for the study of the public policies applied within this space and, consequently contribute to propose more sustainable land use and occupations / A preocupação mundial com as atividades desenvolvidas na zona costeira e suas consequências leva muitos países a desenvolver estudos e a buscar soluções mediante parcerias. Nessa faixa, são praticadas ações e políticas sem uma orientação cooperativa, provocando ocupação conflituosa de uso e processo de degradação ambiental. Como causas, estão: o desconhecimento dos bens públicos e de seus recursos ambientais, como também a falta de integração dos setores governamentais e a sociedade. Esta tese tem como objetivo geral estruturar um modelo da gestão costeira integrada para o Município de Fortaleza, capital do Estado do Ceará. Para isso, discute os planos, programas e projetos para a administração da zona costeira integrada, a ser feita pelos municípios, estados e União visando a proporcionar condições para desenvolver projetos de uso e ocupação do solo sustentáveis, contribuindo para a qualidade do ambiente. A metodologia adotada fundamentou-se na análise documental para a zona costeira, à luz do referencial teórico-conceitual que trata dos temas zona costeira, gestão integrada na zona costeira e uso e ocupação do solo. O esquema metodológico inicia com o conhecimento do espaço e de seus recursos, problemas, e identificação das atividades econômicas que provocam esses problemas. A continuação se desdobra com a análise das políticas e seus instrumentos. O conceito de zona costeira analisado de forma integrada com o referencial teórico permitiu construir as bases para o estudo das políticas nesse espaço e, consequentemente, contribuir, dessa forma, para soluções de uso e ocupação
219

Benthic habitat mapping using multibeam sonar systems

Parnum, Iain Michael January 2007 (has links)
The aim of this study was to develop and examine the use of backscatter data collected with multibeam sonar (MBS) systems for benthic habitat mapping. Backscatter data were collected from six sites around the Australian coastal zone using the Reson SeaBat 8125 MBS system operating at 455 kHz. Benthic habitats surveyed in this study included: seagrass meadows, rhodolith beds, coral reef, rock, gravel, sand, muddy sand, and mixtures of those habitats. Methods for processing MBS backscatter data were developed for the Coastal Water Habitat Mapping (CWHM) project by a team from the Centre for Marine Science and Technology (CMST). The CMST algorithm calculates the seafloor backscatter strength derived from the peak and integral (or average) intensity of backscattered signals for each beam. The seafloor backscatter strength estimated from the mean value of the integral backscatter intensity was shown in this study to provide an accurate measurement of the actual backscatter strength of the seafloor and its angular dependence. However, the seafloor backscatter strength derived from the peak intensity was found to be overestimated when the sonar insonification area is significantly smaller than the footprint of receive beams, which occurs primarily at oblique angles. The angular dependence of the mean backscatter strength showed distinct differences between hard rough substrates (such as rock and coral reef), seagrass, coarse sediments and fine sediments. The highest backscatter strength was observed not only for the hard and rough substrate, but also for marine vegetation, such as rhodolith and seagrass. The main difference in acoustic backscatter from the different habitats was the mean level, or angle-average backscatter strength. However, additional information can also be obtained from the slope of the angular dependence of backscatter strength. / It was shown that the distribution of the backscatter. The shape parameter was shown to relate to the ratio of the insonification area (which can be interpreted as an elementary scattering cell) to the footprint size rather than to the angular dependence of backscatter strength. When this ratio is less than 5, the gamma shape parameter is very similar for different habitats and is nearly linearly proportional to the ratio. Above a ratio of 5, the gamma shape parameter is not significantly dependent on the ratio and there is a noticeable difference in this parameter between different seafloor types. A new approach to producing images of backscatter properties, introduced and referred to as the angle cube method, was developed. The angle cube method uses spatial interpolation to construct a three-dimensional array of backscatter data that is a function of X-Y coordinates and the incidence angle. This allows the spatial visualisation of backscatter properties to be free from artefacts of the angular dependence and provides satisfactory estimates of the backscatter characteristics. / Using the angle-average backscatter strength and slope of the angular dependence, derived by the angle cube method, in addition to seafloor terrain parameters, habitat probability and classification maps were produced to show distributions of sand, marine vegetation (e.g. seagrass and rhodolith) and hard substrate (e.g. coral and bedrock) for five different survey areas. Ultimately, this study demonstrated that the combination of high-resolution bathymetry and backscatter strength data, as collected by MBS, is an efficient and cost-effective tool for benthic habitat mapping in costal zones.
220

Public participation in the marina developments at Port Vincent and Wallaroo on the Yorke Peninsula, South Australia

Alexander, Felicity Anne. January 2000 (has links) (PDF)
Bibliography: leaves 98-103. Examines the role of public participation in coastal protection and coastal management in two marina developments proposed for Yorke Peninsula. The study concluded that there was potential for the South Australian Planning System to incorporate sustainable development and involve the public to a greater extent. The Environmental Impact Assessment process has been perceived as a means of incorporating the principles of ecologically sustainable development at a community level, but the extent to which this has occured for the marina developments at Port Vincent and Wallaroo is limited.

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