This tutorial explains how to calculate the Shannon Wiener diversity index and Evenness.
The samples of 5 species are 60,10,25,1,4. Calculate the Shannon diversity index and Evenness for these sample values.
Sample Values (S) = 60,10,25,1,4 number of species (N) = 5
shannon diversity index and Evenness
First, let us calculate the sum of the given values.
sum | = (60+10+25+1+4) |
= 100 |
No of sample | pi=sample/sum | ln(pi) | pi*ln(pi) |
---|---|---|---|
60 | 0.60 | -0.51 | -0.31 |
10 | 0.10 | -2.30 | -0.23 |
25 | 0.25 | -1.39 | -0.35 |
1 | 0.01 | -4.61 | -0.05 |
4 | 0.04 | -3.22 | -0.13 |
sum=100 | SUM = -1.07 |
H=1.07
Hmax=ln(N)=ln(5)=1.61 Evenness=H/Hmax=1.07/1.61=0.66
Shannon diversity index(H)=1.07 Evenness =0.66