4.6.3 Index of Diversity

Formula for Index of Diversity

$$D = \frac{N(N-1)}{\sum n(n-1)}$$

Where:

• D = Index of Diversity.
• N = Total number of organisms of all species.
• n = Total number of organisms of each individual species.
• Σ = Sum of (calculated for each species).

How to Calculate the Index of Diversity

1. Count the total number of organisms (N) in the community.
2. Count the total number of individuals for each species (n).
3. Substitute the values into the formula and calculate Σ n(n-1) for all species.
4. Divide by . $N(N−1)N(N-1) \ by\ Σn(n−1)\Sigma n(n-1)$

Interpreting the Index of Diversity

• High D value: Indicates high biodiversity, meaning a large number of species and balanced population sizes.
• Low D value: Indicates low biodiversity, meaning few species or dominance of one species.

Factors Affecting the Index of Diversity

1. Habitat Destruction: Reduces the number of species and disrupts ecosystem balance.
2. Pollution: Affects sensitive species, reducing their populations.
3. Deforestation: Removes habitats, decreasing species richness and abundance.
4. Agriculture: Monoculture reduces habitat variety and species diversity.