The entire water column in marine ecosystems, regardless of depth. Plants and algae in the pelagic zone directly or indirectly support most of the ocean's animal life. Because plant growth is confined to the shallow depths of the pelagic zone reached by light (epipelagic zone, 0-650 ft/0-200 m), much of the biological activity in the pelagic zone is concentrated in near-surface waters. The pelagic zone is further subdivided by depth into the mesopelagic zone (650-3,280 ft/200-1000 m), bathypelagic zone (3,280-13,125 ft/1000-4000 m) and abyssopelagic zone (greater than 13,125 ft/4000 m), each zone inhabited by a distinctive fauna. These deeper fauna are nourished largely by organic matter (e.g. dead plankton, fecal material) settling from surface waters.

See Also

Littoral Zone; Neritic Zone; Photic Zone; Phytoplankton; Zooplankton