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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.
51

Variabilité multi-échelles de la météorologie et des aérosols en situation littorale sous influence industrielle / Multi-scale variability of meteorology and aerosols in littoral situation under industrial influence

Gengembre, Cyril 19 June 2018 (has links)
Sur un site multi-influencé par des émissions urbaines et industrielles, l'analyse de la pollution aux aérosols, au voisinage des sources, requiert une connaissance multi-échelles de la dynamique atmosphérique. une campagne de mesure a été développée afin d'étudier la variabilité météorologique et micro-météorologique et l'évolution des particules, en particulier, submicroniques, sur une durée d'une année. Des oscillations de la concentration en aérosols, autour de la moyenne régionale, ont été identifiées le long du littoral dunkerquois, et attribuées aux phénomènes météorologiques locaux à proximité des industries. Des méthodes de reconnaissance et d'apprentissage supervisé, faisant appel aux mesures par anémomètre ultrasonique et aux profils verticaux du vent par lidar Doppler, ont été mises en œuvre pour établir la variabilité de phénomènes pertinents dans les événements de pollution de l'air : brise de mer, brouillard, front et tempête. L'analyse d'une base de données de six ans a permis de montrer que l’occurrence annuelle des brises de mer est corrélée à celle du nombre de journées anticycloniques. Par ailleurs, la fréquence annuelle des brouillards pourrait être liée à la concentration annuelle régionale en aérosols. L'analyse des covariances du vent a révélé deux situations contrastées, à faible et à fort flux turbulents. Le brouillard et la brise de mer, de faible flux, génèrent une pollution élevée aux PM₁, et sont le siège d'une forte concentration en aérosols organiques oxygénés (aérosols secondaires). Les situations à fort flux, favorisant les échanges verticaux, sont associées à une forte variabilité des sulfates particulaires. L'observation de longue durée a permis de mettre en évidence la construction d'épisodes de pollution particulaire, au cours de séquences de phénomènes météorologiques locaux, du fait des sources locales, mais aussi par incorporation de la pollution à plus grande échelle. / On a site that is multi-influenced by urban and industrial emissions, the analysis of aerosol pollution, in the vicinity of sources, requires a multi-scale knowledge of atmospheric dynamics. A measurement campaign was developed in order to study the meteorological and micro-meteorological variability and the evolution of particles, in particular, submicronic evolution, during a one-year period.Oscillations of the aerosol concentration around the regional average were identified along the Dunkirk coastline, and were attributed to the local meteorological phenomena close to the industries. Recognition and machine learning methods using measurements by an ultrasonic anemometer and vertical wind profiles by a Doppler lidar, were implemented to define the variability of relevant phenomena in air pollution events : sea breeze, fog, front and storm. A six-years database analysis has highlighted a correlation between the annual sea breeze occurrence and the annual number of anticyclonic days. Furthermore, the annual fog frequency could be connected with the annual regional concentration of aerosols. Analysis of wind covariance revealed two contrasting situations, low-level and high-level turbulent fluxes. The fog and the sea breeze, with low-level fluxes, generate a high PM₁ pollution and are in favor of a high organic oxygenated aerosols concentration (secondary aerosols). High-level fluxes situations, favoring vertical exchanges, are associated with a large variability of sulfate aerosols. The long-term observation, made it possible to highlight the development of episodes of particulate pollution during local weather phenomena, owing to the local emissions, but also by taking into account the larger-scale pollution.
52

Samhällsplaneringens påverkan av fritidsboende : En fallstudie av sex kust och skärgårdskommuner / The impact of recreational housing on planning : A case study of six coastal and archipelago municipalities ​

Larsson, Sara January 2018 (has links)
Second homes are a widespread part of the Swedish landscape and in many municipalities along the coastline the population can vary seasonally due to that. This cause planning issues for the municipalities, in how they plan their infrastructure, service etc. Studies has also shown that there are two sides in the discussion about second homes, some areas want to attract second home owners because they believe that this group help the municipality to grow while others try to attract permanent residents and restrict new development of second homes. The subject has been of discussion for a long time from many angels, for instance implementation of regulations to prevent second homes.  The purpose of this thesis is to investigate what planning strategies municipalities apply in areas that change so heavily in population depending on season. The method for this thesis is based on a mixture between comparative analysis and content analysis of six comprehensive plans and two policy documents from six municipalities with archipelagos. Furthermore, from the content analysis of the different documents, three themes were produced from the strategies which then were compared in comparative analysis where similarities and differences were highlighted. The themes were population and housing, infrastructure and transport communication, service, business sector and labor. The analysis was subsequently put into context with related academic research such as urbanization theories, rural gentrification, planning theories among others. This ended with a discussion and conclusion. Conclusively the analysis show that municipalities no longer plan for second homes but for permanent residents, the municipalities believed that it is reactionary to plan for second home owners and not primary for permanent residents. / Fritidsboende är en utbredd del av det svenska landskapet och i många kommuner längs kusten kan befolkningen variera säsongsmässigt på grund av det. Detta skapar viss planeringsproblematik för kommunerna i hur de planerar sin infrastruktur, service etc. Studier har också visat att det finns två sidor i diskussionen om fritidsbostäder, vissa områden vill locka fritidsboende eftersom de anser att denna grupp hjälper kommunen att utvecklas medan andra försöker locka permanenta invånare och begränsa ny utveckling av fritidsbostäder. Ämnet har diskuterats länge och från många vinklar, exempelvis implementering av regelverk för att förhindra fritidsbostäder. Syftet med detta examensarbete är att undersöka vilka planeringstrategier kommuner tillämpar i sådana områden som skiftar så kraftigt i befolkningen säsongsvis. Metoden i denna studie har bestått av en blandning mellan komparativ analys och innehållsanalys på sex översiktsplaner och två styrdokument gällande kust och skärgården från sex kust- och skärgårdskommuner Från innehållsanalysen av de olika dokumenten, producerades tre teman från de strategier som sedan jämfördes i den komparativa analysen, där likheter och skillnader lyfts fram. Teman var befolkning och bostäder, infrastruktur och kommunikation, service, näringsliv och arbetsmarknad. Analysen relaterades sedan till forskningsöversikten och den teoretiska utgångspunkten Detta avslutades med en diskussion och slutsats. Sammanfattningsvis visar analysen att kommunerna inte längre planerar för fritidsboende utan för fastboende, kommunerna menade att det är förlegat att planera för främst fritidsboende och inte fastboende.
53

[en] PROJECTIONS OF FUTURE SCENARIOS OF SHORELINE BEHAVIOR: ATAFONA AND GRUSSAÍ BEACH (RJ) BASED ON THE DYNAMIC TREND OBSERVED IN THE PERIOD FROM 1954 TO 2022 / [pt] PROJEÇÕES DE CENÁRIOS FUTUROS DE COMPORTAMENTO DA LINHA DE COSTA ENTRE ATAFONA E GRUSSAÍ (SÃO JOÃO DA BARRA, RJ) A PARTIR DA TENDÊNCIA DINÂMICA OBSERVADA NO PERÍODO DE 1954 A 2022

ISABELLE AFONSO VIEIRA DE SOUZA 14 November 2023 (has links)
[pt] A zona costeira é caracterizada por possuir certa fragilidade devido a sua complexa dinâmica ambiental, que é diretamente correspondente a interação dos agentes continentais e marinhos que, nem sempre, atuam em equilíbrio. Sendo assim, a intensa ocupação humana nas regiões costeiras, muitas vezes de forma desordenada, vem intensificando este desequilíbrio gerando consequências e impactos, usualmente negativos, ao ambiente costeiro e a população que habita a beira mar. Neste contexto, o presente trabalho compreende a realização do monitoramento continuado para o trecho do litoral entre Atafona e Grussaí, localizado em São João da Barra, litoral norte fluminense, através da projeção de cenários futuros de comportamento da linha de costa, para a temporalidade de 5, 10, 15, 20, 25 e 30 anos, baseados na tendência de comportamento de diversos pontos fixos observado através da dinâmica mapeada sobre séries históricas de fotografias aéreas e imagens de satélite nos últimos 68 anos. Os resultados encontrados para os cenários futuros mostram a retrogradação da linha de costa a uma velocidade média de -2,78m/ano na região afetada pelo processo erosivo e uma progradação de +2,51 m/ano onde ocorre predominantemente o processo de acreção. Mantendo-se a dinâmica atualmente delineada, o cenário futuro para os próximos 30 anos aponta que a região próxima ao pontal de Atafona continuará sendo a mais afetada pela perda de terreno costeiro em resposta à dinâmica erosiva, onde a maior taxa linear encontrada é de -161,10m a partir da atual linha de costa; na praia de Grussaí, a incorporação de sedimentos devido o processo de acreção tende a produzir uma progradação da linha de costa atual de cerca de +127,10m. / [en] The coastal zone is characterized by having a certain fragility due to its complex environmental dynamics, which is directly corresponding to the interaction of continental and marine agents that, not always, act in balance. Thus, an intense human occupation in coastal regions, often in a disorderly way, has intensified this imbalance, generating consequences and impacts, usually negative, to the coastal environment and a population that inhabits the seashore. In this context, the present work comprises the carrying out of continuous monitoring for the stretch of coast between Atafona and Grussaí, examination in São João da Barra, Rio do Janeiro s north coast, through the projection of future behavior scenarios. coastline, for the temporality of 5, 10, 15, 20, 25 and 30 years, based on the behavior trend of each fixed point observed through the dynamics mapped in the last 68 years. The results found for future scenarios show the displacement of the coastline at an average speed of -2.78 m/year in the region affected by the erosion process and +2.51 m/year where the progradation process occurs. Keeping the currently outlined dynamics, the future scenario for +30 years points out that the region close to the Atafona point will continue to be the most affected by the erosion dynamics, where the highest linear rate found is -161.10m from the current line of coastline in the region, while at Grussaí beach, the progressive process will have added +127.10m to the current coastline.
54

L'effectivité des instruments de protection et d'aménagement du littoral méditerranéen : cas de l'Algérie / Effectiveness of the instruments for the protection and the urban planning of the Mediterranean coast : the case of Algeria

Foury, Nazim Fouad 29 September 2017 (has links)
Le littoral algérien est caractérisé par une grande richesse en ressources naturelles et offre d’importantes potentialités économiques. Néanmoins, cette portion du territoire est victime de son succès et se trouve confrontée, par conséquent, à une multitude de problèmes tels que la surexploitation de ses ressources amplifiés par une urbanisation massive qui s'accélère de plus en plus mais également par une pollution et une dégradation des zones côtières. Afin de répondre au mieux aux nombreuses incohérences résultant de ces divers problèmes qui frappent le littoral algérien, l’État doit veiller à mettre en place les mesures nécessaires pour trouver un juste équilibre entre l’utilisation de cet espace et sa préservation. L’analyse approfondie du dispositif institutionnel et législatif mis en place par les pouvoirs publics algériens démontre qu’il y a une réelle insuffisance en matière de gouvernance côtière et que les textes juridiques sont lacunaires en ce qui concerne la préservation et l’aménagement du littoral. Le principal défi de l’État est de pallier ces carences en mettant en place une politique de gestion intégrée et globale du littoral qui en permettrait un développement équilibré et durable / The Algerian coastline is characterized by rich natural resources which offer important economic potential. Nonetheless, this part of the country finds itself victim of its own success and have to face a multitude of problems, especially the over-exploitation of its resources which have been amplified by a massive urbanization that is accelerated more and more, but also by pollution and a deterioration of the coastal areas. Moreover, and to best answer the numerous incoherencies that result from these multiple problems that hit the Algerian coastline, the state has to take necessary measures to find a right balance between the use of this space and its preservation. The thorough analysis of the institutional and legal framework put in place by the Algerian public authorities, proves the existence of a real inadequacy in terms of coastal governance, as well as incomplete judicial texts with regards to coastal preservation and development. The primary challenge of the government is to redress these shortcomings, by putting in place an integrated and global management policy of the coast that will allow a balanced and sustained development of this space
55

The impact of climate change effects on the planform of a headland-bay beach on the southern coast of South Africa

Hugo, Pierre-Malan 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The various consequences of climate change pose a significant threat to developments near the coast. These threats include saltwater intrusion, coastal erosion and flooding. In the coastal context, the climate change effect often raising the most concern is that of sea-level rise. Much work has therefore been done on the linear setback caused by a rise in sea-level. In order to get the full picture of possible changes caused by sea-level rise, the secondary effects of a rising sea-level also need to be considered. Sea-level rise could cause changes to the nearshore wave climate and could have impacts such as coastal erosion and changes to the coastline shape. The primary objective of this study was therefore to investigate the effects of sea-level rise on the nearshore wave climate and, consequently, the coastline stability. Other consequences of climate change considered in this study include increasing average wave heights and a rotation of offshore wave directions. The many headland-bay beaches on the South African coastline are generally in a state of dynamic equilibrium and find their planforms based on the local wave climate. Changes to the wave climate may therefore disrupt the equilibrium shapes of these bays. This study was therefore also aimed at investigating the effects of the changes to the wave climate on the stability of headland-bay beaches. The three consequences of climate change expected to affect the nearshore wave climate were identified as (1) sea-level rise; (2) an increased wave height; and (3) changing offshore wave angles. Although changes to storm frequency and intensity are also possible, the impacts of these changes were not studied. In order to assess the impacts of the three considered changes on a typical headland-bay beach, two numerical models were set up for Mossel Bay – a headland-bay beach on the southern coast of South Africa. The modelling approach included a wave transformation model to calculate nearshore wave climates from offshore data and a coastline model to assess the stability of the bay under the changed nearshore wave climates. The model results indicated that the rising sea-level alone would cause changes in the nearshore wave direction. These changes were shown to alter the longshore sediment transport regime such that rotations are expected in the south-western corner and eastern end of Mossel Bay. These rotations do not include the cross-shore effects of inundation and erosion, as suggested by models such as the Bruun Model. The results for an increased offshore wave height were inconclusive. The southerly rotation in offshore wave angles was shown to affect the nearshore wave angles. These changes affected the longshore transport regime such that the outward sediment transports were reduced. A minor accretion resulted in the centre of the bay for a 1° southerly rotation in offshore wave angles. For a 2° rotation, the extent of accretion increased and shifted towards the eastern end of the bay, primarily due to the dominance of south-westerly waves in the local wave climate. A valuable observation was made regarding the current stability of Mossel Bay. Inter-tidal reefs are present along three sections of the bay. These reefs protect the coastline such that the current bay shape contains sharp bends between the reefs. Under a rising sea-level, however, the effect of the reefs will become less pronounced. If a water level should be reached where these reefs become less significant, the planform of the bay is expected to smooth out through a significant redistribution of sediment. This smoothing effect was shown to cause erosion of the coastline in the order of 80m near the town of Klein Brak River. / AFRIKAANSE OPSOMMING: Die verskeie gevolge van klimaatsverandering bied ‘n merkwaardige bedreiging vir ontwikkelings naby die kus. Hierdie bedreigings sluit die versouting van varswaterbronne, kuserosie en oorstromings in. Vir kusgebiede is seevlakstyging gereeld die effek van klimaatsverandering wat die meeste kommer wek. Dus is heelwat navorsing rakende die direkte erosie as gevolg van seevlakstyging reeds gedoen. Om die volle beeld van die gevolge van ‘n stygende seevlak te verkry, is dit egter nodig om ook die sekondêre effekte hiervan in ag te neem. Seevlakstyging kan veranderinge in die golfklimaat naby die kus veroorsaak, en kan impakte soos kuserosie en veranderende baaivorms tot gevolg hê. Die primêre doel van hierdie studie is dus om die effek van seevlakstyging op die golfklimaat by die kus en gevolglik die stabiliteit van die kuslyn, te ondersoek. Benewens die styging van die seevlak word die effekte van groter gemiddelde golfhoogtes en die rotasie van diepsee golfrigtings ook in hierdie studie ondersoek. Die vele landpunt-baaie (headlandbay beaches) op die Suid-Afrikaanse kus is meestal in ‘n dinamiese ekwilibriumtoestand, waarvan die vorm deur die lokale golfklimaat bepaal word. Veranderinge aan dié golfklimaat mag dus die ekwilibrium vorms van sulke baaie versteur. Hierdie studie het dus ook die stabilititeit van landpuntbaaie onder ‘n veranderende golfklimaat ondersoek. Die drie gevolge van klimaatsverandering wat verwag word om die golfklimaat naby die kus te beïnvloed is geïdentifiseer as (1) seevlakstyging; (2) vergrote golfhoogtes; en (3) veranderende diepsee golfhoeke. Veranderinge aan die frekwensie en intensiteit van storms is ook moontlike gevolge van klimaatsverandering, maar die impakte hiervan is nie in die studie ondersoek nie. Twee numeriese modelle is toegepas om die impak van die drie bogenoemde gevolge op Mosselbaai – ‘n tipiese landpunt-baai aan die suidkus van Suid-Afrika – te ondersoek. ‘n Golfmodel is ingespan om die golfklimaat naby die kus te bepaal waarna ‘n kuslynmodel gebruik is om die stabiliteit van die baai onder die veranderde golfklimaat te ondersoek. Die resultate van die studie dui daarop dat die golfhoeke naby die kus beïnvloed word deur seevlakstyging. Daar is aangetoon dat dié veranderinge die langsstroomvervoer sodanig sal verander dat kuslynrotasies in die suid-westelike hoek asook die oostelike rand van Mosselbaai verwag word. Hierdie rotasies sluit nie die lineêre landwaartse verplasing van die kuslyn as gevolg van erosie en oorstroming in nie. Die effek van vergrote golfhoogtes kon nie met akkuraatheid ondersoek word nie. Daar is wel gevind dat die suidwaartse rotasie van diepsee golfhoeke rotasies in die golfklimaat naby die kus veroorsaak. Hierdie rotasies verander die langsstroom sedimentvervoer sodanig dat die uitwaartse sedimentvervoer verminder word en ‘n klein opbou van sediment in die middel van die baai vir ‘n 1° diepsee rotasie verwag word. Vir ‘n 2° suidwaartse rotasie is daar ‘n groter opbou van sediment wat verder ooswaarts veplaas is. Die ooswaartse veplasing is primêr ‘n gevolg van die oorheersing van suid-westelike golftoestande in die golfklimaat. ‘n Waardevolle gevolgtrekking rakende die huidige stabiliteit van Mosselbaai is ook gemaak. Langs drie gedeeltes van die Mosselbaaise kus word riwwe in die gebied tussen hoog- en laagwater aangetref. Hierdie riwwe beskerm die kus sodanig dat skerp kinkels in die vorm van die baai tussen die riwwe gesien kan word. Wanneer die seevlak styg, word die beskermende effek van die riwwe egter minder doeltreffend. Indien ‘n watervlak bereik word waar dié effek genoegsaam verminder is, word daar verwag dat die baai deur ‘n merkwaardige verplasing van sediment die kinkels sal uitstryk. Deur hierdie proses word erosie in die orde van 80m naby die dorp van Klein Brakrivier verwag.
56

Évolution du trait de côte, bilans sédimentaires et évaluation des zones à risques sur le littoral du Nord-Pas-de-Calais : analyse multi-échelles par LiDAR aéroporté / Shoreline evolution, sediment budget and assessment of areas at risk from coastal hazards on the coast of Nord-Pas-de-Calais : a multi-scale analysis using airborne topographic LiDAR

Crapoulet, Adrien 02 September 2015 (has links)
Les plages sableuses et les dunes côtuères occupent encore de nos jours une place importante dans la zone côtière du Nord-Pas-de-Calais. Ces accumulations sableuses, qui sont parfois le seul rempart protégeant les zones basses de la plaine côtière des submersions marines, sont des milieux particulièrement vulnérables dans le contexte actuel de l'élévation du niveau de la mer associée au changement climatique. Les objectifs principaux de la thèse étaient d'analyser les variations du trait de côte et du bilan sédimentaire à l'échelle régionale, d'apprécier le rôle des variations du volume sédimentaire sur la stabilité de la ligne de rivage, et d'évaluer les zones les plus menacées par les risques littoraux dans un avenir proche, de travail reposant en grande partie sur l'utilisation de données topographiques acquises par LiDAR aéroporté entre 2008 et 2014 ainsi que de photographies aériennes de 1963 à 2009. L'analyse de l'évolution du trait de côte a montré des évolutions contrastées, que ce soit spatialement ou temporellement. En effet, plusieurs portions de littoral ont connu une propagation du trait de côte à long terme, comme à court terme, tandis que d'autres sites ont subi un très fort recul à l'échelle de plusieurs décennies, mais aussi ces dernières années. La comparaison entre l'évolution du trait de côte et le volume initial du haut de plage en 2008, a montré que les reculs les plus importants se sont essentiellement produits dans les secteurs où l'on pouvait observer une absence de haut de plage à marée haute. Sur plusieurs sites, nos résultats suggèrent également qu'à partir d'un volume seuil de sédiments sur le haut de plage, le trait de côte est stable ou montre une tendance à la propagation vers le large. La cartographie de l'aléa de submersion marine à l'horizon 2050, prenant en compte la hausse du niveau marin liée au changement climatique, a montré clairement des franchissements du cordon dunaire sur plusieurs sites. Cette cartographie étant établie sur les données topographiques les plus récentes, à savoir décembre 2013 et janvier 2014, ces submersions potentiells ont une forte probabilité de se produire bien plus tôt que l'année 2050 en raison des forts taux d'érosion constatés sur certains massifs dunaires. Le calcul des bilans sédimentaires de l'ensemble du littoral régional, a montré, dans l'ensemble, une tendance à l'accrétion. Cette accrétion est d'autant plus significative pour le haut de plage et les dunes côtières, hormis pour quelques sites qui connaissent un grave déficit sédimentaire (particulièrement dans la baie de Wissant et sur la rive nord de la baie de l'Authie). Ces résultats suggèrent que la côte du Nord-Pas-de-Calais ne se trouve pas dans une situation de pénurie sédimentaire mais connaitrait plutôt une accumulation sur la majeure partie de son linéaire côtier. / Sandy beaches and coastal dunes still represent a significant portion of the coastal of Nord-Pas-de-Calais, northern France. These sandy accumulation landforms, which sometimes constitute the only defense protecting low-lying coastal areas from coastal flooding, are particularly vulnerable to sea level rise associated with climate change. The main objectives of the thesis were to analyze shoreline change and coastal sediment budget at the regional scale, to assess the role of changes in sediment volume on shoreline stability,and to evaluate areas at risk from coastal hazards in the near future, using airborne topographic LiDAR data collected between 2008 and 2014 and aerial photographs from 1963 to 2009. Analyses of shoreline change revealed spatially as well as temporally variables evolutions.Seaward shoreline progradation occured along several stretches of coastline at multidecadal and short times-scales, while significant coastal retreat took place at other sites during the same time periods. The comparison between coastline evolution and the initial volume of the upper beach in 2008 showed that the higher retreat rates were mainly observed in areas where the upper beach was lacking at high tide. Our results also suggest that there is a sediment volume threshold on the upper beach at each site above which the coastline is stable or progrades seaward. Mapping of areas at risk of marine flooding in 2050, taking into account a projection of sea level rise due to climate change, clearly shows that the submersion of coastal dunes would take place at several sites during storm-induced high water level events. The mapping of these areas at risk being based on topographic data collected in December 2013 and January 2014, coastal flooding is very likely to occur much earlier than 2050 at several sites, however, where very high rates of coastal retreat result in severe erosion of the coastal dunes. The calculation of sediment budget based on the repetitive LiDAR surveys shows that, overall, sediment accretion predominates over the entire regional coastal zone. This accretion is particularly significant for the upper beach and coastal dunes, except for a few sites that are characterized by a strong sediment deficit (particularly Wissant bay and the Northern shore of the Authie estuary). These results suggest that the coastal zone of Northern France does not experience sediment shortage, but is rather dominated by sediment storage in the backshore of the sand beaches
57

La concertation lors de la cartographie des aléas littoraux dans les Plans de Prévention des Risques : enjeu majeur de prévention / Dialogue during coastal hazards mapping in risks prevention plans : major prevention issue

Perherin, Céline 01 December 2017 (has links)
L’élaboration des Plans de Prévention des Risques Littoraux (PPRL) « prioritaires », définis suite à la tempête Xynthia de 2010, a provoqué des débats, souvent conflictuels, entre l’Etat et les collectivités territoriales au sujet des cartes d’aléas submersion marine ou recul du trait de côte. Cette recherche doctorale s’attache à la compréhension du processus de construction de ces cartes. Elle analyse les facteurs influençant cette cartographie à partir de ce que représentent les cartes d’aléas pour chaque acteur. Les résultats de cette recherche mettent en évidence que les études d’aléas sont peu issues des connaissances territoriales et abordées sous un angle expert complexe. Les acteurs locaux s’approprient ainsi difficilement les nouvelles connaissances sur les aléas littoraux. La forte présence des aspects techniques et la mécanique d’élaboration du zonage réglementaire conduisent à une cristallisation des débats des PPRL sur la cartographie des aléas. Ces débats cachent aussi souvent des conceptions distinctes de la politique de prévention et des intérêts divergents entre acteurs agissant à échelles spatiales et temporelles différentes. L’ouverture restreinte des discussions par l’Etat lors de la cartographie des aléas de référence et de l’élaboration du zonage conduit à une faible territorialisation des PPRL et rend difficile leur intégration au sein des politiques locales de prévention des risques littoraux et d’aménagement du territoire. Cette thèse révèle ainsi l’importance cruciale de la concertation et d’une entrée par le territoire, pour mettre en place une appropriation active des connaissances sur les aléas et favoriser l’intégration du PPRL au sein de l’action publique territoriale. / The development of Coastal risks prevention plans, identified as priorities after Xynthia storm in 2010, has revealed divisive debates, between the state services and territorial authorities, about coastal flooding or coastline recession mapping. This PhD research deals with the understanding of coastal hazards mapping. It analyses the factors which influence this process based on what do the maps represent for each stakeholder.The research results highlight that hazards studies sparsely come from territorial knowledge and are often approached from a complex expert angle. Thus, new knowledge is hardly managed by local stakeholders. Significant debates about technical aspects and the process of regulatory zoning conception lead to the fact that hazards mapping crystallizes the PPRL debates. Actually, these debates often hide different conceptions of prevention policy and opposing interests of stakeholders acting at different spatial and temporal scales. The few opened discussions purposed by state services during reference hazards mapping and zoning conception lead to a low territorialization of the PPRL and make their integration in local policies of coastal risks prevention and of land use planning difficult.Thus, this PhD highlights the crucial role of dialogue and of an input by the territory, in order to start an active appropriation of hazards knowledge and to enable the PPRL integration within the territorial public policy.
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Les établissements littoraux de la province romaine de Lyonnaise : Contribution à l'étude de l'habitat dispersé et de l'exploitation des ressources maritimes sur les côtes de l'Atlantique et de la Manche dans l'Antiquité / Coastal settlements of the Roman province of Lugdunensis : occupation and economy of the Atlantic and English Channel coast

Driard, Cyril 12 December 2011 (has links)
La Lyonnaise est la province gauloise la plus maritime, avec un trait de côte s’étendant sur plus de 3000 km de long. Ce travail de recherche concerne l’habitat dispersé (villae, fermes, ateliers) sur son littoral, du Ier au Vème siècle. Son objectif est de comprendre comment cette forme d’occupation et de gestion de l’espace rural a été adaptée au milieu géographique particulier qu’est le littoral. La question de la diffusion sur la façade Atlantique du phénomène des villae maritimes se pose également. Tout d’abord, les questions de typologie, de configuration et d’architecture des ensembles bâtis sont abordées. Ensuite, l’économie de ces établissements et en particulier l’exploitation des ressources maritimes est analysée. Bien que la documentation disponible soit ancienne et peu détaillée, des opérations archéologiques récentes ont contribué à renouveler les connaissances scientifiques sur le sujet, notamment sur les ateliers de salaisons et de sauces de poissons en Gaule et leurs productions. / With a coastline of at least 3000 kilometers, the Roman province of Lugdunensis is the most maritime area of the Gallic territories. This thesis deals with the occupation of the coastal countryside, dotted with villae, farms and craft workshops, between the 1st and 5th centuries AD. The main objective is to understand how the rural areas were managed and how roman society adapted to and transformed this landscape. This study also addresses the question of the dissemination of “villae maritimae” along the Atlantic coast. Themes covered included the organisation of Roman coastal settlements and their architectural influences, the role of farms in the management and exploitation of marine resources, and lastly, the types of products produced. The archaeological information available for use is extensive although dated, difficult to exploit, and as a such the analysis suffers. However, several recent surveys and excavations have allowed for the collection of new data about Roman salting and fish sauce workshops in western Gaul. Atlantic Coast and English Channel
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Le principe de solidarité écologique / The principle of ecological solidarity

Danna, Charlotte 07 September 2018 (has links)
Adopté par l’article 2 de la loi n°2016-1087 de reconquête de la biodiversité, de la nature et des paysages du 8 aout 2016, le principe de solidarité écologique appelle « à prendre en compte, dans toute prise de décision publique ayant une incidence notable sur l’environnement des territoires concernés, les interactions des écosystèmes, des êtres vivants et des milieux naturels ou aménagés ». Ce principe général du droit de l’environnement inscrit à l’article L110-1 du code de l’environnement est destiné à conserver les interactions écosystémiques et les processus écologiques ainsi qu’à améliorer la gestion environnementale des territoires. La dualité de son objet en fait un principe d’une grande richesse, qui devrait concerner de nombreuses décisions. Divers fondements supranationaux, au sein de la jurisprudence et dans les textes internationaux et européens peuvent ainsi lui être attribués. Dans un contexte d’interdépendance écologique, l’évolution de la dimension internationale et européenne du principe reste essentielle pour juger de ses effets au regard de la conservation de la biodiversité. Au niveau du droit interne, son ancrage au cœur de l’équilibre de l’environnement lui apporte un rayonnement particulier. Il conforte le droit à un environnement équilibré et prolonge les principes constitutionnels de prévention et de développement durable. Face à la crise d’extinction mondiale de la biodiversité menaçant notre survie, le principe de solidarité écologique se présente comme cette ultime chance de la conserver. Deux grands ensembles de dispositifs permettent de mesurer la dynamique du principe de solidarité écologique : la trame verte et bleue et la gestion intégrée de la mer et du littoral. Ils constituent une base pour concevoir la solidarité écologique et représentent ainsi le commencement d’un droit nouveau. Le principe de solidarité écologique appelle à les renforcer et, de manière plus générale, à faire évoluer l’ensemble des décisions concernées par le principe. / Adopted by article 2 from act nr 2016-1087 concerning the reconquest of biodiversity, nature and landscape of August 8th 2016, the principle of ecological solidarity calls “for taking into consideration the interactions of ecosystems, living creatures and natural or developed environments in all public decisions having a notable impact on the environment of the territories concerned”.This general principle of environmental law inscribed in article L110 1 of the environmental code is designed to preserve the interactions of ecosystems and ecological processes as well as to improve the environmental management of the territories. The duality of its objective renders it a highly valuable principle which should be applied to numerous decisions. Various supranational foundations, within jurisprudence and in international and European laws, can thus be assigned to it. In the context of ecological interdependence the evolution of the international and European dimension of the principle remains essential in order to see the benefits concerning the safeguarding of biodiversity. It is greatly enhanced, as regards internal law, by the fact that it is at the very center of the environment's equilibrium. It justifies the right to a balanced environment and extends the constitutional principles of prevention and sustainable development. Confronted with the crisis of world-wide biodiversity extinction that threatens our survival, the principle of ecological solidarity emerges as the last chance to preserve it. Two major groups of systems allow us to measure the dynamics of the principle of ecological solidarity: the green and the blue line belt network and the Ocean and coastline Governance Framework. They constitute a basis on which to develop ecological solidarity and represent the beginnings of new legislation. The principle of ecological solidarity requires them to be reinforced and more generally to advance all decisions concerned by the principle.
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Mapping Landcover/Landuse and Coastline Change in the Eastern Mekong Delta (Viet Nam) from 1989 to 2002 using Remote Sensing

SOHAIL, ARFAN January 2012 (has links)
There has been rapid change in the landcover/landuse in the Mekong delta, Viet Nam. The landcover/landuse has changed very fast due to intense population pressure, agriculture/aquaculture farming and timber collection in the coastal areas of the delta. The changing landuse pattern in the coastal areas of the delta is threatened to be flooded by sea level rise; sea level is expected to rise 33 cm until 2050; 45 cm until 2070 and 1 m until 2100. The coastline along the eastern Mekong delta has never been static, but the loss of mangrove forests along the coast has intensified coastline change. The objective of the present study is to map the changes in landcover/landuse along the eastern coast of the Mekong delta; and to detect the changes in position of the eastern coastline over the time period from 1989 to 2002.To detect changes in landuse, two satellite images of the same season, acquired by the TM sensor of Landsat 5 and the ETM+ sensor of Landsat 7 were used. The TM image was acquired on January 16, 1989 and ETM+ image was acquired on February 13, 2002. The landcover/landuse classes selected for the study are water, forest, open vegetation, soil and shrimp farms. Image differencing and post classification comparison are used to detect the changes between two time periods. Image to image correction technique is used to align satellite images. Maximum likelihood supervised classification technique is used to classify images. The result of the classification consists of five classes for 1989 and 2002, respectively. Overall accuracies of 87.5% and 86.8%, with kappa values of 0.85 and 0.84 are obtained for landuse 1989 and landuse 2002, respectively. The overall accuracy for the change map is 82% with kappa value 0.80. Post classification comparison is carried out in this study based on the supervised classification results. According to the results obtained from the post classification comparison, a significant decrease of 48% in forest and a significant increase of 74% in open vegetation and 21% in shrimp farms area observed over the entire study area. The coastline obtained by the combination of histogram thresholding and band ratio showed an overall advancement towards the South China Sea. The results showed that new land patches emerged along the eastern coast. The amount of new land patches appeared along the coast of the Mekong delta is approximately 2% of the entire study area.

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