Jump: M  - N - O - P


M Top


Macrobenthos: Benthic organisms greater than or equal to 0.5mm in length.

Marine Protected Area (MPA): Set locations assigned strong governmental and legal protection to restrict the occurrence of certain activities.

Marine snow: Fragile organic aggregates resulting from the collision of dissolved organic molecules or from the degradation of gelatinous substances such as larvacean houses; usually enriched with microoraganisms.

Maerl: fine-grained carbonate-rich mud.

Megafauna: Animals exceeding 2 cm in length.


N Top


Nekton: Organisms with swimming abilities that permit them to move against currents.

Nudibranch: Sea slug. A member of the mollusc class Gastropoda that has no protective covering as an adult. Respiration is carried out by gills or other projections on the dorsal surface.

Nutrients: Elements and compounds which are needed by organisms for maintenance and growth.


O Top


Oceanic: Associated with sea-water environments seaward of the shelf-slope break.

Oceanic Crust: The outermost layer of rock on the earth's surface, underlying the deep ocean. Oceanic crust is created at mid-ocean ridges where plates are moving apart.

Octocorallia: A subclass of the Anthozoa. Each polyp has eight tentacles extending radially from a central point.

Offshore: The comparatively flat submerged zone of variable width extending from the breaker line to the edge of the continental shelf.

Overfishing: Enormous fishing pressure resulting in fish stocks becoming overfished, and age structure degrading or even collapsing.
P Top


Patchiness: Organisms occur in aggregations.

Pelagic: Living in the open-water environment, seaward of the shelf-break, also used to describe the open water environment.

Phylum: A major grouping in taxonomy.

Plankton: Passively drifting or weakly swimming organisms that are not independent of currents, including mostly microscopic algae, protozoa and larval forms of higher animals.

Polychaeta: Class of annelid worms that includes most of the marine segmented worms.

Polyp: Typically sedentary soft-bodied component of Cnidaria (corals, sea pens etc), which comprises a trunk that is fixed at the base; the mouth is placed at the opposite end of the trunk, and is surrounded by tentacles.

Population: A group of organisms of the same species inhabiting a geographical area.

Predation: The consumption of one organism by another.

Productivity: A measure of the capacity of a biological system, starting with the primary production derived from chemo- or photosynthesis .