Most of the oxygen is produced by phytoplankton. These primary producers (also called autotrophs) are the first link in the food chain in the oceans. Because of this food source, many animals also live in this zone.
Most of the oxygen is produced by phytoplankton. These primary producers (also called autotrophs) are the first link in the food chain in the oceans. Because of this food source, many animals also live in this zone.
