Zonation in the Ocean

The ocean can be divided into zones.

neritic zone• shallow water over the continental

shelf• lots of light

oceanic zone• water over the deep sea• light only at the surface

ocean light zones

photic zone

• sunlit, upper layers of ocean• made up of euphotic and disphotic zones

ocean light zones

euphotic zone

• sunlit, upper layers of ocean• upper 150 m – depending on where you are• phytoplankton can survive and

photosynthesize here

ocean light zones

disphotic zone

• twilight zone• enough light to see, but not enough for

photosynthesis• extends to a few hundred meters deep

ocean light zones

aphotic zone

• permanently dark• no sunlight• no photosynthesis• most of ocean• extends to sea floor

vertical zonation of the ocean depends on depth

The Epipelagic Zone

The Mesopelagic Zone

The Bathypelagic Zone

The Abyssopelagic Zone

The Hadal or Hadopelagic Zone