Which of the following produces the maximum amount of organic matter?

This productivity is expressed in terms of weight $(gm^{-2})$ or energy $(kcal,m^{-2})$.

The total energy fixed by a gram plant ($Cicer$ $arietinum$) in an ecosystem on the whole is called

Energy storage at the consumer level is called:

Why are oceans the least productive ecosystems?

$A$: In secondary productivity,no new organic matter is formed.
$R$: It is only the utilisation of part of food manufactured by primary producers in the building of consumer biomass.