Question

Discuss the main reason for the low productivity of ocean.

Answer 1

Ocean water is not as mineral rich as the land. Minerals are essential for photosynthesis. ... Penetration of light cannot be the reason for low productivity as it is a healthy 250 m in ocean as compared to roughly 25 m in tropical rain-forests with thick canopies.

Answer 2

Productivity actual means primary productivity which is the biomass or dry weight produce by the plants per unit area during the photosynthesis. In ocean, there is insufficient radiation as sunlight decreases with the increasing depth which decreases the rate of photosynthesis. Decrease in rate of photosynthesis decreases the growth of aquatic plants and animals. Minerals and nutrients can also be a retarding factor based on location of the oceans. So, there will be less productivity than land which is 170 billion tons compared to 55 billion tons ion oceans.