Who attempted to put a price tag on nature's life-support services?

In a given habitat,we have $20$ plant species and $20$ animal species. Should we call this 'diversity' or 'biodiversity'? Justify your answer.

Assertion : Diversity observed in the entire geographical area is called gamma diversity.
Reason : Biodiversity decreases from high altitude to low altitude.

Which among the following shows highest amphibian species diversity?

Which one of the following pairs of geographical areas show maximum biodiversity in our country?

In tropical forests like $..........$,the species of vascular plants are $10$ times more than those in temperate forests of the mid-west of the $U.S.A$.