Index of Diversity
What is Species diversity?
Community 1
Community 2
The formula to measure the index of diversity
value for N – 1
Maximum diversity
Introduction
Species diversity is described as the number of species in a community. The more species, the higher the diversity. What if there are two separate communities like this:
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Community #1 has 150 individuals per each of 20 different species (3000 individuals in total)
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Community #2 has 10 individuals per each of 19 species, and 2990 individuals of the last species (3000 individuals in total)
It doesn’t take a complex formula to figure out that community #1 is far more diverse compared to community #2, despite them having the same number of species and individuals. The distribution of individuals to species is important in determining a community’s diversity.
The above example is easy enough, but for most purposes a formula is needed. This formula measures the index of diversity, which is simply a measure of diversity in a community. By calculating it and obtaining a numerical value, different communities can be easily compared.
Right here it comes….
No, don’t run away yet! Wait and see how easy it is to work out….
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- D = Diversity index
- N = total number of all organisms
- n = total number of organisms of each species
- Σ = sum of
Now it’s simply a matter of replacing numbers…..