Species diversity is concerned with two specific aspects:
1. **Species Richness**: This refers to the number of different species in a particular area or ecosystem. It focuses on the variety of species present.
2. **Species Evenness**: This aspect looks at how evenly distributed the individuals of each species are within a community. It considers whether a few species dominate the area or if there is a more equal distribution of individuals across different species.
In summary, species diversity concerns both the number of species (species richness) and how evenly distributed they are (species evenness) within a specific ecosystem or area.