Water Cycles - Life In The Ocean
Ninty seven percent of the water on or near Earth's surface is ocean water. Living organisms in the ocean have adapted to the ocean environment. Ocean environments are conrolled by many components. A few of the important componets includes temperature, light, depth, nutrients, currents, tides, waves, and nature of the seafloor.
Consider the underwater organism known as kelp. It must be attached to the bottom and yet be in water that is shallow enough for light to penetrate. This quick growing organism also requires an ample supply of nutrients which on the west coast are provided by upwelling currents caused by prevailing west winds.
Now consider tropical corals. These must be attached to bottom in area where waves and currents bring in food. Each type of coral requires specific temperatures; therefore clear water results from low-nutrient water.
Lastly, consider the large mammals known as blue whales. These large organisms exist in all the world's open oceans which are rich in krill. The Antarctic krill feeds manly on photoplankton near the ocean's surface. Other krill feeds on both zooplankon and photoplankton near the ocean's surface.

