Which index is quantitative and used to represent species diversity?

The Shannon Wiener Index is a quantitative measure used to represent species diversity within a community. It takes into account both the richness (the number of different species) and the evenness (how evenly individuals are distributed among those species) of a community. The index is calculated using the formula that integrates the proportion of each species and the natural logarithm of that proportion. This approach effectively captures the complexity of biodiversity by providing a single value that reflects both how many different species are present and how balanced their populations are.

In contrast, while other indices mentioned might also relate to aspects of diversity or community structure, they may not be focused solely on diversity in the same quantitative manner. The Simpson's Index, for instance, tends to emphasize dominance and the probability of two randomly selected individuals being of the same species, rather than capturing the full breadth of diversity in the community. The Phylogenetic Diversity Index considers the evolutionary relationships between species but is not focused purely on species diversity. The Biomass Index primarily looks at the mass of organisms and is not a standard measure of biodiversity itself. Therefore, the Shannon Wiener Index stands out as the most comprehensive tool for quantifying species diversity in ecological studies.