Estuaries are irreplaceable natural resources that must be managed carefully for the mutual benefit of all who enjoy and depend on them. The estuarine environment is a very dynamic and complex environment, which poses threats and challenges to estuary managers and estuary users. As estuarine management is a very knowledge-intensive task, researchers in the Eastern Cape Estuaries Management Programme (ECEMP), estuary managers and estuary users have recently turned their attention to knowledge management as one of the important means of ensuring continued success and effective management of estuaries. However, knowledge management as an emerging field has been slow in formulating universally accepted methodologies for auditing, capturing, creating, acquiring, sharing and utilising knowledge. Existing methodologies do not adequately address, in particular, the knowledge audit requirements of non-traditional or non-constrained and non-formalised organisations. The purpose of this study was to develop a context-specific model for auditing knowledge in the Eastern Cape estuaries, with special reference to the Tyolomnqa Estuary. The study intended to identify the knowledge community, analyse existing knowledge and knowledge needs and gaps in the Tyolomnqa Estuary area. In order to achieve the objectives, the descriptive research design, employing the case study approach was used in the study. Focus groups and unstructured interviews were used to collect data. A literature review, concentrating on values and issues surrounding the management of estuaries and key issues in knowledge management and knowledge auditing, was carried out. The collected data was analysed according to themes such as knowledge sources, knowledge identification and knowledge needs and gaps. The study found that the communities of the Tyolomnqa Estuary lack knowledge concerning the management of estuaries. The study also established that the community has little knowledge on who to contact for expert advice in addressing estuarine issues. Furthermore, the study found that the community needed knowledge on how to address estuarine management issues and how that knowledge could be accessed. Based on the findings and the literature review, the study proposes a context-specific knowledge audit model for non-traditional organisations. The model is meant to assist non-traditional organisations to evaluate their knowledge health or status, and to develop a much better understanding of the know-how and how it can be used to effectively sustain their services. The model can be used to successfully implement knowledge management strategies in non-traditional organisations. The model needs to be tested for verification and validation purposes. / Thesis (M.I.S.)-University of KwaZulu-Natal, Pietermaritzburg, 2003.

The South African coastal and marine environment is an essential ecologic and economic asset. Its associated services and products are substantially contributing to economic growth and sustainable development of the country. However, it is internationally and nationally recognised that land-based marine pollution (LBMP) is the most important single risk to the health and sustainability of coastal and marine waters and the associated ecosystems. The regulation of LBMP at the national level is still difficult and challenging. The issue of LBMP management has only recently been introduced in South Africa with the development of the National Programme of Action to Protect Marine Environment from Land-based Activities, 2008. South Africa is only starting to consider the question of LBMP regulation. This thesis aims to conduct a critical analysis of the South African regulatory framework pertaining to LBMP in comparison to international best practice and the French regulatory framework, in order to identify the key South African challenges in this regard and to make recommendations to address them. In order to do so, this research commences by providing an analysis of LBMP and the theoretical foundations associated with LBMP regulation, as promoted by international best practice. The study identifies and assesses the main regulatory features to be considered in the development, implementation and/or assessment of a regulatory framework pertaining to LBMP. These features will form the methodological framework to conduct the comparative legal assessment between the French and South African regulatory frameworks pertaining to LBMP. This thesis then provides a detailed and thorough legal analysis of the French and South African regulatory frameworks pertaining to LBMP using the methodological framework developed using guidance from international best practice. Finally, based on lessons learnt from the comparative legal study, this study concludes with a set of recommendations for the South African context. / Thesis (LL.D.)--North-West University, Potchefstroom Campus, 2011.

The South African coastal and marine environment is an essential ecologic and economic asset. Its associated services and products are substantially contributing to economic growth and sustainable development of the country. However, it is internationally and nationally recognised that land-based marine pollution (LBMP) is the most important single risk to the health and sustainability of coastal and marine waters and the associated ecosystems. The regulation of LBMP at the national level is still difficult and challenging. The issue of LBMP management has only recently been introduced in South Africa with the development of the National Programme of Action to Protect Marine Environment from Land-based Activities, 2008. South Africa is only starting to consider the question of LBMP regulation. This thesis aims to conduct a critical analysis of the South African regulatory framework pertaining to LBMP in comparison to international best practice and the French regulatory framework, in order to identify the key South African challenges in this regard and to make recommendations to address them. In order to do so, this research commences by providing an analysis of LBMP and the theoretical foundations associated with LBMP regulation, as promoted by international best practice. The study identifies and assesses the main regulatory features to be considered in the development, implementation and/or assessment of a regulatory framework pertaining to LBMP. These features will form the methodological framework to conduct the comparative legal assessment between the French and South African regulatory frameworks pertaining to LBMP. This thesis then provides a detailed and thorough legal analysis of the French and South African regulatory frameworks pertaining to LBMP using the methodological framework developed using guidance from international best practice. Finally, based on lessons learnt from the comparative legal study, this study concludes with a set of recommendations for the South African context. / Thesis (LL.D.)--North-West University, Potchefstroom Campus, 2011.

Since the study on the Port Alfred/Kenton-on-Sea/Boknes linefishery by Hecht and Tilney (1989) there have been substantive changes to the linefish management environment in South Africa. Using the Port Alfred linefishery as a model, the aim of this study was to evaluate the effectiveness of the linefish management regulations that were implemented by Marine and Coastal Management (MCM) since 1992, and to assess the behaviour and 'status' of the fishery in response to these changes. Changes to both the licensing structure and catch regulations have had a significant effect on the functioning of many aspects of the Port Alfred linefishery (fishing effort, catch composition, cpue) as well as on the structure of the fishery and its socio-economic profile. Overall commercial cpue decreased from 1985 to 1998. Since 1998 there has been a significant increase in cpue (from 2.3 Kg.fisher⁻¹ hour⁻¹ to a peak of 4.8 Kg.fisher⁻¹.hour⁻¹ in 2005. This was attributed to good catches of geelbek, particularly in 2005, 2007 and 2008 (during these years geelbek contributed an average of 35% to the total landings in comparison to a mean contribution of II % between 1985 and 2004). However, size spectra analysis suggests that the increase in overall cpue since 1998 misrepresents the actual status of the fishery. If geelbek is excluded from the analysis on the grounds that it is the only species in the fishery that is highly migratory, susceptible to recruitment fluctuations and it does not contribute to the catches on a year round basis, then the results suggest that the fishery is still in a declining phase despite the 80% reduction in commercial effort and numerous stricter catch regulations (e.g. size/bag limits). Furthermore, the cpue of silver kob, which has been the "mainstay" species of the fishery, has consistently declined over the last 23 year period (from 1.69 Kg.fisher⁻1 .hour1 in 1986 to 0.86 Kg.fisher⁻1.hour⁻1in 2007). The substantial reduction in commercial effort in the fishery from 33 vessels in 2001 to 13 in 2002 resulted in a shift from commercial to recreational fishing. The number of active commercial vessels in Port Alfred alone decreased from 29 in 1989 (Hecht 1993) to four in 2008. During the same timeframe, the number of regularly active recreational vessels had almost doubled (16 in 1989 to 26 in 2008). Despite the greater number of recreational boats in the fishery they only landed approximately half the average yearly tonnage of the commercial vessels (21,5 and 44,7 tonnes,annum-I , respectively) between 2006 and 2008, This was ascribed to the differences in catch regulations for the two sectors, Furthermore, it was speculated that increasing operating costs and narrowing profit margins have contributed to lower levels of compliance in both the commercial and recreational sectors since 2006, For example, 16% of silver kob landed during 2006-08 were under the minimum size, Despite the changes made to the regulations since 1998 and the 60,6% reduction In legislated commercial effort in the fishery between 2001 and 2002 it was concluded that the fishery has continued to decline, Except for the good recruitment of geelbek (which may be due to regulatory changes made in 1992) the changes in the management environment have had no measurable positive effect on this fishery, It is recommended that commercial effort should not be allowed to increase beyond the current number of active boats, that there should be an area restriction on all commerciallinefish vessels, that the current recreational bag limit for silver kob should be re-assessed, there should also be a concerted and nationally funded effort to educate recreational anglers about the merits of catch and release, and the frequency of catch inspections of both sectors should be increased, / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

The aims of this study were to determine the potential use of biomarkers at multiple levels of biological organisation together with a fish community bioindicator to assess the estuarine health status of three temporarily open/closed estuaries. The estuaries investigated were the East Kleinemonde (EK), Old Woman's (OW) and Mtana (MTN), all of which are situated in the Eastern Cape Province. Three biomarkers, the acetylcholinesterase (AChE) assay, lipid peroxidation (LPx) assay, liver histopathology and a condition factor were used to determine sub-organism health and one bioindicator, the Estuarine Fish Community Index (EFCI), was used as a bioindicator of community health. The estuarine-dependent marine species Rhabdosargus holubi was selected as an indicator species for the sub-organism level analyses. The results from the community analyses indicated that the EK and OW estuaries were in 'good' condition, while the MTN was found to be in 'moderate' condition. Histological analyses revealed that R. holubi from all three estuaries showed signs of pathological changes to the liver, with the fish from the MTN eliciting the highest occurrence of these changes. The LPx assay found that R. holubi from both the OW and MTN showed signs of oxidative damage in the liver tissue, but those from the EK did not appear to be affected. The AChE assay showed that only the fish from the OW had been affected by anticholinesterase compounds. A laboratory study was undertaken using R. holubi as a positive control for the AChE and LPx assay. The fish were exposed to 3 μg/L chlorpyrifos, a known cholinesterase inhibitor, for six hours and their tissues were examined for changes to LPx levels and AChE activities. AChE activity was significantly inhibited (Mann Whitney U test, Z = 3.65, n = 38, P < 0.001) by the exposure, but LPx levels were not significantly affected. A composite index incorporating the biomarkers at different biological levels of organisation was developed. The index was designed to assist managers and scientists to determine whether the ichthyofauna of a system was being affected by environmental stressors and what management interventions could be undertaken to ameliorate the water quality in an estuary. The index was applied to the three estuaries investigated during the present study and both the OW and MTN were assessed to be in need of immediate management intervention. The fish in the OW were found to be stressed at all the sub-organism levels measured and the reason for this was hypothesised to be as a result of golf course activities in this adjacent estuary. A number of management actions are proposed to reduce the sub-organism stress observed in the fish from the OW. The livers of fish from the MTN were shown to be under stress; however the causative agent of this stress was unknown because there is no formal development in the MTN catchment. However, a possible contaminant source is proposed and management interventions to alleviate the stress on the biota of the MTN are suggested. The EK does not require immediate management intervention, however, continuous routine monitoring is recommended to ensure that conditions do not deteriorate. Shortcomings of the index were outlined and a number of suggestions were made in terms of other measures of biological health which could be incorporated into the index.

Studies of the dunefield systems crossing the Cape St. Francis headland in the Eastern Cape have focused on the role that wind plays in sediment transfer in coastal dunefield systems, with limited consideration of the role of water. The aim of this study was to improve understanding of the morphology, processes and patterns within the Oyster Bay HBD system, focussing particularly on surface water and groundwater interactions and the role of surface water in sediment transfer across the dunefield system. An extensive field survey was conducted, to collect related data, complimented by spatial and temporal analysis of the study area using GIS. The key findings from this research were the apparent differences between the western and eastern regions of the dunefield with regard to specific drivers and the respective processes and responses. Wind is the major driver of change up to and across the crest of the dunefield. In the eastern region water (ground water, surface water and the Sand River System) is the primary agent of sediment flux through processes of aggregation and slumping as well as episodic events including debris flows. This study has highlighted a need for further quantitative studies that investigate the movement of sediment through dunefield systems such as this (where water is at or near the land surface). The paradigm that sediment flux is entirely due to wind is almost certainly simplistic, and deeper understanding of these systems is needed / Maiden name: Elkington, Lauren

Le but principal de cette étude est de comprendre le fonctionnement de la zone interface, continuum terre-mer au Liban. Suite à l’anthropisation spécifiquement la construction des barrages, les apports du fleuve vers la mer en termes de quantité et qualité, sont modifiés de nos jours. Le fleuve Ibrahim, ayant le débit le plus important parmi les fleuves libanais, interrompu par trois barrages, a été choisi comme étude de cas représentant les fleuves côtiers libanais. Les différents paramètres retenus ont permis de dégager des résultats intéressants. Au niveau de l’eau de surface marine le panache fluvial est décelé par l’étude des paramètres hydrologiques des masses d’eaux superficielles. Les résultats montrent aussi que l’apport fluviatile est le contributeur principal en nutriments au niveau de la région côtière durant la saison humide, élucidé par les teneurs en nitrates et silice dissoute. D’autre part, le transfert des particules de la zone côtière vers le large, à travers la pente continentale, se fait par l’intermédiaire de couches néphéloïdes.L’origine des sédiments et de leurs constituants est mise en relief en analysant plusieurs paramètres sédimentaires. La combinaison des paramètres granulométriques et géochimiques organiques et inorganiques et l’application des tests statistiques a permis de distinguer entre deux environnements de dépôt. (1) Les environnements littoraux (≤ 30 m) ou zone de « bypass » où le sable fin et la matière organique autochtone dominent. (2) Les environnements profonds (≥ 60 m) ou zones de dépôts où la fraction fine et la matière organique allochtone dominent.Sur l’ensemble du suivi l’état chimique de l’eau du fleuve au niveau des deux stations échantillonnées, déduit des teneurs en nutriments et macrofaune benthique, est considéré comme bon à très bon d’après les normes internationales Finalement, l’analyse des éléments traces métalliques confirme la faible contribution anthropique dans les stations marines et fluviatiles échantillonnées malgré la densité de population croissante au niveau de la région côtière Libanaise. / The main purpose of this study is to understand the functioning of the coastal zone, land-sea continuum in Lebanon. Following the construction of dams, the contributions of the river towards the sea in terms of quantity and quality, are modified nowadays. The Ibrahim river, having the highest flow among the Lebanese rivers, interrupted by three dams, was chosen as a case study representing the Lebanese coastal rivers. The various parameters retained made it possible to obtain interesting results. At sea surface water level, the river plume is detected by studying the hydrological parameters of surface water.The results also show that the river is the main nutrient contributor in the coastal region during the wet season, elucidated by the nitrate and dissolved silica contents. On the other hand, the transfer of particles from the coastal zone to the open sea, across the continental slope, takes place through the nepheloid layers.The origin of sediments and their constituents is highlighted by analyzing several sediment parameters. The combination of organic and inorganic particle size and geochemical parameters and the application of statistical tests made it possible to distinguish between two deposition environments. (1) Coastal environments (≤ 30 m) or “bypass” area where fine sand and autochtonous organic matter dominate. (2) Deep environments (≥ 60 m) or deposit areas where the fine fraction and allochthonous organic matter dominate.The ecological state of the river water at the two sampled stations, deduced from the contents of nutrients and benthic macrofauna, is considered good to very good according to international standards. Finally, the analysis of metallic trace elements confirms the low anthropogenic contribution in the marine and river stations despite the increasing density of the population in the Lebanese coastal region.

Les zones côtières ne sont prises en compte dans les budgets globaux de CO2 atmosphérique que depuis peu. Il s’avère que bien qu’elles ne représentent globalement que de faibles superficies, les flux de carbone et de nutriments y sont très significatifs à l’échelle globale. On sait peu de chose sur le comportement des écosystèmes lagunaires vis-à-vis du CO2 et, encore moins des zones intertidales où les échanges avec l’atmosphère ont lieu alternativement avec l’eau et le sédiment. Les objectifs de cette étude ont été d’une part, d’établir le bilan de carbone échangé entre la lagune d’Arcachon, l’atmosphère et le milieu terrestre, et d’autre part de mettre en relation ces flux avec la production nette de l’écosystème (NEP) afin de mieux caractériser le statut métabolique de celle-ci ainsi que les facteurs environnementaux clés. Pour cela, nous avons mis en place pour la première fois et à différentes saisons et stations, des mesures directes de flux de CO2 par Eddy Corrélation, une méthode fonctionnant en continu pendant l’immersion et l’émersion. En parallèle, les apports de carbone terrestre sous ses différentes formes ont été quantifiés par un suivi annuel sur 9 rivières alimentant la lagune. L’export total de carbone par le bassin versant à travers les eaux de surface des rivières est estimé à 116 t C km-2 an-1 dont 39% est exporté à la lagune sous forme organique dissoute (DOC) du fait de la prédominance de podzols dans le bassin versant. La forte minéralisation de la matière organique terrestre dans les sols et eaux souterraines sursature largement les eaux en CO2 et l’export sous forme de carbone inorganique dissoute (DIC) représente environ 21%. La formulation d’un modèle mathématique, le « StreamCO2-DEGAS », basé sur les mesures de pCO2, de concentrations et de compositions isotopiques en DIC a permis de montrer que 43% de l’export total de carbone était dégazé sous forme de CO2 depuis les rivières vers l’atmosphère, réduisant alors le flux net entrant dans la lagune à 66 t C km-2 an-1. Concernant la mesure de flux verticaux, l’analyse cospectrale ainsi que les résultats obtenus en adéquation avec les contrôles physiques et biologiques aux différentes échelles tidale, diurne et saisonnières, ont permis de valider la méthode de l’Eddy Covariance en zone intertidale. Sur l’ensemble de la période de mesures, les flux de CO2 étaient faibles, variant entre -13 et 19 µmol m-2 s-1. Des puits de CO2 atmosphérique à marée basse le jour ont été systématiquement observés. Au contraire, pendant l’immersion et à marée basse la nuit, des flux positifs ou négatifs ou proche de zéro ont été observés suivant la saison et la station étudiées. L’analyse concomitante des flux de CO2 et des images satellites du platier à marée basse le jour a clairement permis de discriminer l’importance relative des deux cycles métaboliques distincts des principaux producteurs primaires avec (1) les herbiers de Zostera noltii à cycle annuel long, dominant la NEP en été et en automne à la station la plus centrale et (2) les communautés microphytobenthiques, dominant la production primaire brute (PPB) au printemps à la même station et en automne au fond du bassin. Un recyclage rapide de cette production durant l’immersion et l’émersion a aussi clairement été mis évidence. Au vue des différents résultats, la technique d’Eddy Covariance utilisée en zone intertidale laisse envisager d’intéressantes perspectives en termes de connaissances sur les budgets de carbone et les processus écologiques et biogéochimiques dans la zone côtière. / The coastal zone is only taken into account since recently in global carbon budgeting efforts. Although covering globally modest surface areas, carbon and nutrient fluxes in the coastal zone appear significant at the global scale. However, little is known about the CO2 behaviour in lagoons and even less in intertidal zones where exchanges with the atmosphere occur alternatively with the water and the sediment. The purposes of this work are, on one hand, to establish the carbon budget between the Arcachon lagoon, the atmosphere and the terrestrial watershed and on the other hand, to link these fluxes with the net ecosystem production (NEP) and better characterize its metabolic status along with the relevant environmental factors. For the first time, CO2 flux measurements by Eddy Correlation have been carried out at different seasons and stations in the tidal flat. In parallel, the total terrestrial carbon export from river waters has been quantified throughout a complete hydrological cycle in nine watercourses flowing into the lagoon. The total carbon export from the watershed through surface river waters is estimated at 116 t C km-2 yr-1 on which 39% is exported to the lagoon as dissolved organic carbon (DOC) owing to the predominance of podzols in the watershed. Intense organic matter mineralization in soils and groundwaters largely over-saturate river waters in CO2 on which export accounts for 21% as dissolved inorganic carbon (DIC). The mathematical “StreamCO2-DEGAS” model formulation based on water pCO2, DIC concentrations and isotopic composition measurements permits to show that 43% of the total carbon export was degassed as CO2 from the riverine surface waters to the atmosphere, lowering then this latter to 66 t C km-2 yr-1. With respect to the CO2 flux measurements in the lagoon, cospectral analysis and the well accordance of results with physical and biological controls at the tidal, diurnal and seasonal time scales permit to validate the Eddy Correlation technique over tidal coastal zone. CO2 fluxes with the atmosphere, during each period, were generally weak and ranged between -13 and 19 µmol m-2 s-1. Low tide and daytime conditions were always characterized by an uptake of atmospheric CO2. In contrast, during the immersion and during low tide at night, CO2 fluxes where either positive or negative, or close to zero, depending on the season and the site. The concomitant analysis of CO2 fluxes with satellite images of the lagoon at low tide during the day clearly discriminate the relative importance of the two distinct metabolic carbon cycling involving the main primary producers, i.e. (1) the Zostera noltii seagrass meadow predominance on the NEP in autumn and summer in the more central station, with an annual cycling and (2) the microphytobenthos community predominance on the gross primary production (GPP) in spring at the same station and in autumn in the inner part of the bay where a rapid carbon cycling during the immersion and the emersion was clearly highlighted. The different results obtained with the Eddy Correlation technique over tidal flats opens interesting perspectives on the knowledge of the carbon budget and the biogeochemical and ecological processes within the coastal zone.

Le but général de ce travail fut de quantifier la silice biogène (BSiO2) dans les sédiments du continuum de l'Escaut (estuaire – zone côtière), ainsi que son taux de recyclage - rétention. Le coefficient de diffusion moléculaire de la DSi a été déterminé pour différentes valeurs de température et deux salinités et une relation empirique reliant le coefficient de diffusion à la température et à la viscosité de la solution a été établie. La distribution longitudinale de la BSiO2 dans les sédiments de surface, ainsi que les profils verticaux de BSiO2 et de silice dissoute ont été déterminés durant différentes saisons en 2004 et 2005. Les flux de DSi ont été également estimés via des expériences d’incubations et par modélisation des profiles verticaux de DSi. Des expériences de dissolution des sédiments ont permis de déterminer (via modélisation) les constantes cinétiques de vitesse de la BSiO2 et une première évaluation du taux de recyclage de la BSiO2 (5 – 70%). Sur base des calculs à partir des profiles de DSi dans l’eau interstitielle, le taux de recyclage de la BSiO2 varie entre 8 et 92% dans l’estuaire, ce qui correspond à une rétention moyenne de la BSiO2 supérieure à 60%, et souligne ainsi l'efficacité du filtre estuarien par rapport à la silice. En revanche, le recyclage de BSiO2 dans la zone côtière apparaît comme très intensif, avec des valeurs souvent supérieures à 40%. Ces résultats montrent l'importance d'inclure les estuaires dans le calcul des budgets globaux de Si. / The general objective of this study was to quantify the BSiO2 in the sediments of the Scheldt continuum, together with its recycling and retention in this area. First an empirical relation linking the diffusion coefficient of DSi to temperature and salinity was determined, via diffusion experiments. The longitudinal BSiO2 distribution in surface sediments and the vertical BSiO2 and DSi profiles in sediment cores where then measured during 2 years and different seasons, together with other parameters characterizing pore waters, such as alkalinity, pH, sulphate… DSi fluxes were also estimated either directly through whole core incubations measurements or via modelling of interstitial water profiles. BSiO2 dissolution experiments allowed the evaluation of the kinetic rate constants also through modelling of the results, and gave preliminary information over the BSiO2 recycling rates (5 – 70%). The recycling rate as obtained from pore water profiles vary between 8 and 92%, with an average value of about 32%, which highlights the importance of the estuarine filter for silica. Recycling is much more intense in the coastal area, with values up to 40%, which we explain by higher salinity and higher sediment permeability. The different experiments and results also indicated that secondary mineral precipitation might be and important process affecting BSiO2 in the Scheldt sediments.<p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

La mer joue un rôle essentiel dans la régulation du climat et dans l'équilibre écologique. Les océans et les mers constituent une source de richesse, un immense réservoir de ressources alimentaires et d'emplois pour un grand nombre de personnes. La mer Méditerranée est un écosystème sensible soumis à de fortes pressions par les activités humaines comme la pêche, l'exploration gazière et pétrolière, l'immersion des déchets ou d'autres matières en mer, le transport maritime, le transfert d'espèces aquatiques envahissantes par les eaux de ballast et le tourisme littoral. La France durement touchée par les naufrages de l'Amoco Cadiz, de l'Erika et du Prestige, a pris de nombreuses initiatives tant au niveau international que régional. La complexité du problème de la pollution marine, due à la diversité des facteurs polluants et à leurs sources diffuses, a favorisé une approche sectorielle. Cette approche s'est traduite par l'adoption, aux niveaux national, régional et international, d'un ensemble disparate de politiques, textes législatifs, programmes et plans d'action dans le domaine de la protection du milieu marin. Il s'agit d'un corps de règles étouffées comprenant des mesures préventives et répressives. La complexité institutionnelle et juridique de la protection du milieu marin empêche pourtant la protection effective de la mer. Dans ce contexte, la communauté internationale encourage la mise en œuvre d'une approche écosystématique pour les océans. À l'échelle européenne, l'adoption de la directive-cadre « stratégie pour le milieu marin » favorise la cohérence entre les différentes politiques européennes et l'intégration des préoccupations environnementales dans toutes les politiques liées à la mer. De plus, l'efficacité de la législation européenne dans le domaine de la lutte contre la pollution marine a été renforcée par l'adoption d'un cadre commun de responsabilité pour la prévention et la réparation des préjudices environnementaux. / The sea plays a vital role in regulating climate and in maintaining ecological balance. The oceans and the sea constitute a source of wealth, an immense reservoir of food resources and of employment for many people. The Mediterranean Sea is a sensitive ecosystem, subject to strong pressures derived from human activities, such as fishing, oil and gas exploration, dumping of waste and other matter in the sea, maritime transport, transfer of aquatic invasive species via ballast water and littoral tourism. France, severely affected by the sinking of the Amoco Cadiz, the Erika and the Prestige, took numerous initiatives not only at an international but also at a regional level. The complexity of the marine pollution problem, due to the diversity of polluting factors and to their diffuse sources, has favored a regional approach. This approach has resulted in the adoption, at a national, regional and international level, of a network of policies, legislative texts, programs and action plans in the field of marine environment protection. It constitutes a stifling body of rules, comprising preventive and repressive measures. The institutional and legal complexity of marine protection hinders, however, the effective protection of the marine environment. ln this context, the international community encourages the implementation of an ecosystem approach to oceans. At European level, the adoption of the Framework Directive «Strategy for the Marine Environment» favours a consistency between different EU policies as well as an integration of environmental considerations into ail policies related to the sea. Furthermore, the effectiveness of European legislation in the field of the fight again marine pollution, has been reinforced by the adoption of a common framework of liability with regard to the prevention and remedy of environment damage.