Mexican trees

The first exercise involves data taken from three forest types in Mexico. The abundances are counts of individual trees. What differences are there in species diversity between the forest types?

library(vegan)
library(reshape)
library(dplyr)
library(ggplot2)
mexveg<- read.csv("/home/aqm/course/data/mexveg.csv")
df<-melt(mexveg,id=1:2)
mexmat<-mexveg[,-c(1,2)]

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https://www.youtube.com/watch?v=FjZV7orhbq0

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