Q.Explain the three indices of species diversity.

Species diversity is expressed at three levels - alpha (within a habitat), beta (between habitats), and gamma (over an entire region) - which together describe biodiversity at increasing spatial scales.

Alpha diversity refers to the species richness and relative abundance of species found within a particular community or habitat, essentially measuring how diverse a single local area is. Beta diversity measures the degree of change in species composition, or turnover, when moving from one habitat/community to another along an environmental or geographical gradient - a high beta diversity means neighbouring communities share few species and are very distinct from one another. Gamma diversity is the overall species diversity across a large area or region, such as a landscape or an entire biogeographic zone, that includes many different communities; it can be thought of as the product/sum of the alpha diversities of the individual communities combined with the beta diversity (turnover) a …