Biodiversity is the diversity of different species together with genetic
variation within each species in a given area. United Nations Environment
Programme (UNEP) defines it as the totality of genes, species and ecosystems in
a region. In simple words biodiversity is the variety of genes, species and
ecosystem in a given region at a given time.
Based on the elements of biodiversity it is
divided into the following types:
(1)
Genetic Diversity – Genetic diversity of
genes within species or population e.g. different varieties of rice. It is
basically the diversity of genes which determines the diversity of species
which in turn determines diversity of a population and ecosystem. More genetic
diversity within a species means greater variability and adaptability of
individuals of species to environmental changes. Lesser genetic diversity leads
to susceptibility to environmental changes and threat of elimination.
Genetic diversity on a
larger scale is sometimes equated with Gene
Pool. A gene pool is the total genetic diversity found within a population
or species. A large gene pool has extensive genetic diversity and is better
able to withstand the environmental stresses. In –breeding contributes to the
creation of small gene pool and makes populations or species more likely to go
extinct when faced with some stress.
(2)
Species Diversity: