Secondary productivity is defined as ...

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

Match the Column-$I$ with Column-$II$ and choose the correct option.

Column-$I$	Column-$II$
$(a)$ $\text{NPP}$ of ocean	$(i)$ $115$ billion tons
$(b)$ Annual $\text{NPP}$ of the whole biosphere	$(ii)$ $170$ billion tons
$(c)$ $\text{NPP}$ of terrestrial ecosystem	$(iii)$ $55$ billion tons
$(d)$ Secondary productivity	$(iv)$ Heterotrophs

Net primary productivity $(NPP)$ in an ecosystem is:

Arrange the following ecosystems in increasing order of mean $NPP$ (Tonnes / ha / year):
$A.$ Tropical deciduous forest
$B.$ Temperate coniferous forest
$C.$ Tropical rain forest
$D.$ Temperate deciduous forest

State whether the following statements are True or False:
$I.$ The total organic matter synthesized by the producers in the process of photosynthesis per unit time and area is known as gross primary productivity.
$II.$ Net primary productivity is the weight of the organic matter stored by the producers in a unit area/volume per unit time.