The level of productivity in oceans can be explained by the fact that the volume of the global ocean is enormous.
The oceans cover about 70% of the earth. This makes the ocean to occupy the largest volume on earth.
In spite of this large volume, the productivity of the ocean is just about 55 billion tons.
This low productivity of the ocean is tied to its large volume and small amount of primary productivity.
Learn more: https://brainly.com/question/22283115