| Deep Ocean |
| The open ocean is the most extensive biome,
although it is split into distinct vertical zones. The top 100 metres
(91 yards), where microscopic phytoplankton have enough sunlight for photosynthesis,
is the most productive zone, with fertility dependent on the seasonal
variation of sunlight and the upwelling of nutrients. Deeper down, a variety
of animals survive, preying on each other or dependent on the rain of
detritus from above. At mid-ocean ridges and hotspots, fumeroles provide
a habitat which is, uniquely, independent of energy from the sun.
North Pacific
Plankton Bloom in the Coral Sea |
