Question

Explain the concept of primary productivity.

Answer 1

It can be defined as the rate at which solar energy is captured by the producer for the synthesis of energy-rich organic molecules through photosynthesis.

It is again of two types:

1. Gross primary productivity (GPP): It refers to the total amount of organic matter (Biomass) produced during photosynthesis by the producer. It is estimated in terms of either chlorophyll content as chl/g dry wt/unit area or photosynthetic numbers as CO₂ fixed/g chl/hour.
2. Net primary productivity (NPP): It refers to the amount of organic matter stored by the producer after meeting the loss by way of respiration. Net primary productivity= Gross primary productivity-Respiration rate.