EARTH SCIENCE > OCEANS > OCEAN OPTICS > APHOTIC/PHOTIC ZONE
Aphotic zone in the ocean, beneath the photic zone, where light intensities
are not sufficient to enable photosynthetic production. Photic zone is
the illuminated zone of the ocean where light intensities are sufficient
for photosynthetic primary production. Also known as the euphotic zone.
Adapted from: Open University. 1989. Seawater: its composition, properties and
behaviour. Pergamon Press. p. 61.