Productivity of an ecosystem is composed of which of the following?

Question

Question

This question was previously asked in

SSC CGL 2022 Tier-I Official Paper (Held On : 02 Dec 2022 Shift 2)

Answer 1

The correct answer is Net primary productivity and gross primary productivity.

Key Points

Primary production is defined as the amount of biomass or organic matter produced per unit area over a time period by plants during photosynthesis.
It is expressed in terms of gm^–2 yr ^–1or (kcal m^–2 ) yr ^–1 to compare the productivity of different ecosystems
It can be divided into gross primary productivity (GPP) and net primary productivity (NPP).
The gross primary productivity of an ecosystem is the rate of production of organic matter during photosynthesis
Net primary productivity, or NPP, is gross primary productivity excluding the rate of energy loss to metabolism and maintenance.
Net primary productivity is the rate at which energy is stored as biomass by plants or other primary producers and made available to consumers.
GPP – R = NPP ( R represents the Respiration losses)

Additional Information

Primary productivity depends on the plant species inhabiting a particular area.
Secondary productivity is defined as the rate of formation of new organic matter by consumers.
The annual net primary productivity of the whole biosphere is approximately 170 billion tons (dry weight) of organic matter.
Despite occupying about 70 per cent of the surface, the productivity of the oceans is only 55 billion tons.