EVERYDAY SCIENCE

Detailed explanation-1: -It undergoes a series of physical, chemical, and biological processes that supply nutrients into the upper water column. The photic zone is home to the majority of aquatic life due to the activity (primary production) of the phytoplankton.

Detailed explanation-2: -In terrestrial environments, primary productivity is generated by trees and other land plants (including planted crops). Most primary producers require nitrogen and phosphorus-which are available as dissolved nutrients in the soil, lakes, and rivers and in the oceans as nitrate, nitrite, ammonia, and phosphorus.

Detailed explanation-3: -Photic Zone is the top layer, nearest the surface of the ocean and is also called the sunlight layer. In this zone enough light penetrates the water to allow photosynthesis. The Disphotic Zone is found just below the Photic Zone and is known as the twilight layer.

Detailed explanation-4: -Higher chlorophyll concentrations and in general higher productivity are observed on the equator, along the coasts (especially eastern margins), and in the high latitude ocean (Figure 4a and b).

Detailed explanation-5: -Most primary production occurs in the upper half of the photic zone (the thin surface layer of lighted water that is rarely deeper than 200 m), in the zone called the euphotic zone (meaning good zone).