The Annual Net Primary Productivity on land and ocean respectively are . . . . . . and . . . . . . billion tons.

Primary productivity depends on.........

What is primary productivity? Give a brief description of the factors that affect primary productivity.

Which of the following ecosystems has the highest gross primary productivity?

The rate at which light energy is converted into chemical energy of organic molecules is the ecosystem's

$A$: 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.