Shannon Diversity Index - Do you need the same species across sites to compare?

#1
Hello,

I comparing fish diversity from the years 2013 to 2018 in a freshwater river system. There are however different species present in some years. Can I still use the Shannon Index to compare diversity? I have attached my calculations below.

Thank you!
 

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#3
Well the index for from 2013 to 2018 can be seen to drop which indicates overall diversity is decreasing over time? Is a stats test required to see if they’re significant?
 

katxt

Active Member
#6
Put the year and diversity into two columns. Analyse, Regression, Linear. Make Year the independent variable and Diversity the dependent variable. Then look for the p value in the output anova table or the coefficients table