Marée noireright|thumb|Travaux de nettoyage après une marée noire. Une marée noire est une catastrophe industrielle et écologique se traduisant par l'écoulement en zone côtière d'une nappe d'hydrocarbures. Cette nappe, qui résulte du déversement volontaire ou accidentel d'une quantité importante de pétrole brut ou de produits pétroliers lourds à la mer, est ensuite ramenée vers la côte par l'effet des marées, des vents ou de courants. L'expression pour désigner ce type de catastrophe a été lexicalisé en français à l’occasion du naufrage du Torrey Canyon.
Deepwater Horizon oil spillThe Deepwater Horizon oil spill (also referred to as the "BP oil spill") was an industrial disaster that began on 20 April 2010 off of the coast of the United States in the Gulf of Mexico on the BP-operated Macondo Prospect, considered to be the largest marine oil spill in the history of the petroleum industry and estimated to be 8 to 31 percent larger in volume than the previous largest, the Ixtoc I oil spill, also in the Gulf of Mexico. The United States federal government estimated the total discharge at .
Exxon Valdez oil spillThe Exxon Valdez oil spill occurred in the Prince William Sound, Alaska, on March 24, 1989. Exxon Valdez, an oil supertanker owned by Exxon Shipping Company bound for Long Beach, California struck Prince William Sound's Bligh Reef, west of Tatitlek, Alaska at 12:04 a.m. and spilled (or 37,000 tonnes) of crude oil over the next few days. The Exxon Valdez spill is the second largest in U.S. waters, after the 2010 Deepwater Horizon oil spill, in terms of volume of oil released.
Biodiversité marineLa biodiversité marine est l'ensemble de la diversité biologique propre aux océans ou en dépendant très directement. Elle est en forte régression (du point de vue de la richesse trophique notamment) depuis plus de , incontestablement du fait des activités humaines et en particulier du fait de la surpêche et de la pollution et artificialisation des fleuves, estuaires, ports et zones côtières. thumb|left|Animaux marins.
Marine microorganismsMarine microorganisms are defined by their habitat as microorganisms living in a marine environment, that is, in the saltwater of a sea or ocean or the brackish water of a coastal estuary. A microorganism (or microbe) is any microscopic living organism or virus, that is too small to see with the unaided human eye without magnification. Microorganisms are very diverse. They can be single-celled or multicellular and include bacteria, archaea, viruses and most protozoa, as well as some fungi, algae, and animals, such as rotifers and copepods.
Marine virusesMarine viruses are defined by their habitat as viruses that are found in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. Viruses are small infectious agents that can only replicate inside the living cells of a host organism, because they need the replication machinery of the host to do so. They can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea.
Planctonthumb|250px|right|Les diatomées sont une des bases des réseaux trophiques océaniques et d'eau douce. Certaines sont considérées comme bioindicatrices de la qualité de l'eau. thumb|250px|right|Zooplancton. Selon Hensen (1887), le plancton (du grec ancien , « errant, instable ») est un groupe polyphylétique d'organismes généralement unicellulaires vivant dans les eaux douces, saumâtres et salées, le plus souvent en suspension et apparemment passivement : gamètes, larves, animaux inaptes à lutter contre le courant (petits crustacés planctoniques, siphonophores et méduses), végétaux et algues microscopiques.
Marine habitatA marine habitat is a habitat that supports marine life. Marine life depends in some way on the saltwater that is in the sea (the term marine comes from the Latin mare, meaning sea or ocean). A habitat is an ecological or environmental area inhabited by one or more living species. The marine environment supports many kinds of these habitats. Marine habitats can be divided into coastal and open ocean habitats. Coastal habitats are found in the area that extends from as far as the tide comes in on the shoreline out to the edge of the continental shelf.
Biologie marinevignette|redresse=1.1|Les écosystèmes marins comptent parmi les plus complexes, les plus répandus et les moins bien connus de notre planète. La biologie marine est l'étude scientifique des organismes et écosystèmes marins, littoraux et estuariens ou d’organismes indirectement liés à l'eau de mer (oiseaux marins par exemple). La biologie marine diffère de l'écologie marine. En écologie marine, les chercheurs se concentrent sur la façon dont les organismes interagissent les uns avec les autres et l'environnement, tandis qu’en biologie marine, les chercheurs étudient l’organisme lui-même.
Marine protistsMarine protists are defined by their habitat as protists that live in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. Life originated as marine single-celled prokaryotes (bacteria and archaea) and later evolved into more complex eukaryotes. Eukaryotes are the more developed life forms known as plants, animals, fungi and protists. Protists are the eukaryotes that cannot be classified as plants, fungi or animals. They are mostly single-celled and microscopic.