How are species related to the concept of biodiversity?

Biologists most often define biodiversity as the "totality of genes, species, and ecosystems of a region".
So if you have a bunch of species of the same kind of animal then that animal would be considered biodiverse. This is a kinda basic concept, and thus hard to elaborate on; you just have to understand what the words mean.

Abay where the river empties into the sea