Seagrass meadows play a very important role from an ecological, sedimentary and economic point of view. They produce more organic matter than the tropical forests and more than 10 l oxygen per m2 per day. Being at the base of many food chains and shelter for several hundreds of animal and plant species, they are of great importance for the maintenance of biological diversity and represent an invaluable economic source.
However, seagrass meadows are in regression because they are subjected to many pressures: littoral constructions, urban and industrial pollution, mechanical destruction and eutrophication of the marine ecosystems resulting from dumping from aquaculture, agriculture and urban activities. They require a sustainable management, which implies a good knowledge of their characteristics, sites, size, state of conservation and the pressures to which they are exposed.