L'accès des navires aux zones portuaires est assuré par le dragage de quantités importantes de sédiments. Les matériaux dragués ne peuvent être immergés que s'ils présentent toutes les garanties d'innocuité pour le milieu marin. Après un rappel sur la géochimie et la toxicité des différents contaminants qui sont adsorbés sur les sédiments, le présent ouvrage propose une approche globale de l'évaluation des risques environnementaux liés aux immersions. Les méthodes de caractérisation des risques à partir de l'analyse chimique (Géodrisk) et de tests de toxicité sélectionnés, de bioévaluation de la qualité des sédiments par la définition d'un Indice d'évaluation de l'endofaune côtière (I2EC) et de biomonitoring actif des zones d'immersion, sont décrites de manière détaillée. Cette démarche ascendante et itérative, appliquée au contexte réglementaire français, permet de satisfaire aux recommandations des conventions internationales et en particulier aux lignes directrices OSPAR.

Concerns over the potential ecological effects of fishing have increased with the expansion of fisheries throughout the marine waters of the United States. Effects of Trawling and Dredging on Seafloor Habitat describes how assessment of fishing impacts depends on gear type, number and location of bottom tows, and the physical and biological characteristics of seafloor habitats. Many experimental studies have documented acute, gear-specific effects of trawling and dredging on various types of habitat. These studies indicate that low mobility, long-lived species are more vulnerable to towed fishing gear than short-lived species in areas where the seabed is often disturbed by natural phenomena. Trawling and dredging may also change the composition and productivity of fish communities dependent on seafloor habitats for food and refuge. The scale of these impacts depends on the level of fishing effort. This volume presents color maps of fishing effort for all regions with significant bottom trawl or dredge fisheries-the first time that such data has been assembled and analyzed for the entire nation.

Expanding a port, deepening a navigation channel or creating new land for development, introduces changes to our physical, social, economic and political environment. Changes may result from events during the construction process, or relate to the nature of the completed structure. Changes can be positive or negative, short-term or long-term, and may affect the immediate vicinity of the project or a larger geographical area. Predicting and assessing all possible effects of a planned dredging activity in a scientifically-sound and reliable manner is essential, so that appropriate control measures can be taken to avoid or mitigate unwelcome impacts. This book provides guidance for a complete holistic environmental evaluation procedure and for the design and implementation of environmental control measures. The book is of particular interest to engineers, government agencies and port authorities, as well as civil engineering consultants and contractors involved in planning and designing dredging, maritime infrastructure and fluvial projects.

The varied use of dredgers has led to the development of a variety of dredger types, from small ones appropriate to modest inshore projects, to very large sea-going dredgers for large-scale projects calling for the storage of dredged material within the ship. This book, which is the first book dedicated to dredging and its environmental impact in the widest sense, contains chapters on dredging operations in the Netherlands, Belgium, the UK, Spain, the US, China and Singapore. Additional chapters discuss more general aspects such as dredging techniques, monitoring of dredging operations, and the prospects of dredging in a changing environment. As well as providing information on dredging activities in different areas, it gives an insight into the activities and problems (environmental or other) involved in modern dredging. It will be of interest to professionals and students alike.

This handbook is the first of its kind to provide a clear, accessible, and comprehensive introduction to the most important scientific and management topics in marine environmental protection. Leading experts discuss the latest perspectives and best practices in the field with a particular focus on the functioning of marine ecosystems, natural processes, and anthropogenic pressures. The book familiarizes readers with the intricacies and challenges of managing coasts and oceans more sustainably, and guides them through the maze of concepts and strategies, laws and policies, and the various actors that define our ability to manage marine activities. Providing valuable thematic insights into marine management to inspire thoughtful application and further study, it is essential reading for marine environmental scientists, policy-makers, lawyers, practitioners and anyone interested in the field.