Question

what is the measure of the bio diversity ?

Answer 1

Measuring the diversity of a species generally incorporates estimates of “richness.” Also referred to as alpha-diversity, species richness is a common way of measuring biodiversity and involves counting the number of individuals – or even families – in a given area.

Answer 2

Biodiversity is usually plotted as taxonomic richness of a geographic area, with some reference to a temporal scale. Whittaker described three common metrics used to measure species-level biodiversity, encompassing attention to species richness or species evenness.

Species richness - the least sophisticated of the indices available.
Simpson index
Shannon-Wiener index
Recently, another new index has been invented called the Mean species abundance index (MSA); this index calculates the trend in population size of a cross section of the species.

Other types of diversity might be plotted against a temporal time scale.

Species diversity
Ecological diversity
Morphological diversity
Genetic diversity
There is also

Phylogenetic diversity
Functional diversity.
I hope this information will help you. In case you need some detail information or any confusion , feel free to comment .
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