What are the three levels of biodiversity?

Explanation

There are three levels of biodiversity-
(1) Genetic diversity (2) Species diversity and
(3) Community/Ecosystem diversity.
(i) Genetic diversity:
(i) Refers to the difference in genetic make-up (number and types of genes) between distinct species and to the genetic variation between distinct populations of the same species.
(ii) Genetic diversity can be measured using a variety of molecular techniques. India has more than 50,000 genetic variants of paddy and 1000 variants of mango.
(iii) Variation of genes of a species increases with diversity in size and habitat, It results in the formation of different races, varieties and subspecies.
(iv) Rouwolfia vomitaria, a medicinal plant growing in different ranges of the Himalayas shows differences in the potency and concentration of active ingredient reserpine due to genetic diversity.
(v) Genetic diversity helps in developing adaptations to change environmental conditions.
(2) Species diversity:
(i) It refers to th variety in number and richness of the species in any habitat. The number of species per unit area at a specific time is called species richness, which denotes the measure of species diversity.
(ii) The Western Ghats have greater amphibian species diversity than the Eastern Ghats. The more is the number of species in an area the more is species richness. The three indices of diversity are - Alpha, Beta and Gamma diversity.
(a) Alpha diversity: It is measured by counting the number of texa (usually species) within a particular area, community or ecosystem.
(b) Beta diversity: It is species diversity between two adjacent ecosystems and is obtaining by comparing the number of species unique to each of the ecosystems.
(c) Gamma diversity refers to the diversity of the habitats over the total landscape of geographical area.
(3) Community/Ecosystem diversity : The variety of habitats, biotic communities, and ecological processes in the biosphere. It is the diversity at ecosystem level due to diversity of niches, tropic levels and ecological processes like nutrient cycles, food webs, energy flow and several biotic interactions.