Diversity analysis: Richness versus evenness

Area of Science:

• Ecology
• Biodiversity Science
• Statistical Ecology

Background:

• Species richness and evenness are key components of biodiversity.
• Previous studies on their relationship yielded contradictory results, suggesting weak correlations.
• Existing research often relied on specific datasets and abundance distributions.

Purpose of the Study:

• To investigate the correlation between species richness and evenness.
• To use randomly generated abundance distributions for more generalizable findings.
• To introduce a new tool, the richness-evenness curve, for diversity analysis.

Main Methods:

• Utilized randomly generated species abundance distributions.
• Applied four well-known diversity measures, including Simpson's indices and the entropy index.
• Analyzed the influence of richness and evenness on diversity metrics.

Main Results:

• No statistically significant correlation was found between richness and evenness.
• Evenness showed the strongest influence on overall diversity.
• Richness was most influential for effective-number diversity formulations.

Conclusions:

• The relationship between richness and evenness is not statistically significant across diverse abundance distributions.
• Evenness and richness play distinct roles in shaping diversity metrics.
• The richness-evenness curve offers a novel approach to visualizing diversity tradeoffs.