1. What is the Species Diversity Index?

The Shannon Diversity Index (H) is a measure of species diversity that considers both species richness and evenness. It quantifies the uncertainty in predicting the species of an individual chosen at random from the community.

2. How Does the Calculator Work?

The calculator uses the Shannon Diversity Index equation:

Where:

• \( p_i \) — Proportion of individuals belonging to species i
• \( \ln \) — Natural logarithm

Explanation: The index increases as both the number of species and the evenness of their proportions increase. Higher values indicate greater diversity.

3. Importance of Diversity Index Calculation

Details: The Shannon Index is widely used in ecology, conservation biology, and environmental monitoring to assess biodiversity, compare ecosystems, and track changes over time.

4. Using the Calculator

Tips: Enter species proportions as comma-separated decimal values (e.g., 0.2,0.3,0.5). All values must be between 0-1 and the sum must equal 1.0.

5. Frequently Asked Questions (FAQ)

Q1: What is a good diversity index value?
A: Values typically range from 1.5 to 3.5, with higher values indicating greater diversity. The interpretation depends on the specific ecosystem being studied.

Q2: How does this differ from species richness?
A: Species richness only counts the number of species, while the Shannon Index also considers how individuals are distributed among species.

Q3: What are the limitations of this index?
A: It assumes random sampling and may be sensitive to sample size. It doesn't account for species identity or phylogenetic relationships.

Q4: Can I use percentages instead of proportions?
A: Yes, but convert percentages to decimal proportions (e.g., 25% = 0.25) and ensure the total sums to 1.0.

Q5: What other diversity indices are commonly used?
A: Simpson's Index, Berger-Parker Index, and Fisher's Alpha are other commonly used diversity measures in ecology.