Biodiversity refers to the variety of forms of life in an area and can be measured in different ways.
In our biosphere immense diversity exists at all levels of biological organization, which ranges from macromolecules within cells to biomes.
The term biodiversity was popularized by Edward Wilson to describe the combined diversity at all the levels of biological organization. The most important are (1) Genetic diversity, (2) Species diversity and (3) Ecological diversity.
Genetic diversity:
-
Genetic diversity is the amount of variation in the genetic material within all members of a population (total number of genetic characteristics in the genetic makeup).
-
It affects a population’s ability to adapt to changing environments.
-
A large population always promotes the genetic diversity required for surviving environmental changes. When a population is reduced to small numbers, the amount of genetic variation is reduced as well.
-
Natural selection suggests the struggle of organisms to survive and reproduce. When genetic variation in a species reduces it reduces the possibility that the species will survive natural selection.
-
Many germplasm reserves or gene banks have been established all around the world to meet present and future needs for plant genetic diversity for economically important plant species
Species diversity:
-
Species diversity refers to the diversity at the species level.
-
It takes into account both species richness and species evenness.
-
Species richness - Suggests simple count of species, number of unique species within an area
-
Species evenness - relative number of individuals of each species in an area (counts how equal are the abundances of the species)
-
Pollution often reduces the species diversity of an ecosystem.