Answer: The species richness is how much species there are in the area. The species evenness is who equal the relative number of species are.
EXPLANATION:
If you have only a few species in an habitats the species richness will be low and if there are a lot of species richness will be high.
But independently of the richness, the evenness is comparing the number of individuals between species. If there are a lot of individuals in a few species and just a little number of individuals in the other species, the evenness will be low.
Hope this helps! C: