ABSTRACT
Biodiversity is the degree of variation of life-forms within a given species, ecosystem, biome or the entire planet. Health of an ecosystem can be measured by biodiversity, which is a function of climate. The term biological diversity was used rst by the wildlife scientist and conservationist Raymond F. Dasmann in 1968 in the book A Different Kind of Country. The term was widely adopted only after more than a decade, when in the 1980s, it came into common usage in science and environmental policy. The biological denition of biodiversity is ‘totality of genes, species and ecosystems of a region’. Biological variation can be identied in four levels:
• Species diversity: Species diversity is the effective number of different species that are represented in a collection of individuals. The effective number of species refers to the number of equally abundant species needed to obtain the same mean proportional species abundance as that observed in the dataset of interest. Species diversity consists of two components, species richness and species evenness.
