We will try to determine if species and functional groups have different impacts on ecosystem processes like NPP and soil nutrients. We will then think about scientifically based methods for ecosystem management over the next century. When species are uneven, one species dominates. The Shannon-Weiner index is an example. Most ecosystem studies on species diversity look at species richness.
Functional diversity describes the richness of different functional groups in an ecosystem.
Here s an example. Imagine two ecosystems, each with 5 species. We say that the functional diversity is higher in the second ecosystems because it has 5 functional groups, whereas the first ecosystem only has one. However, we could also say that the first ecosystem has higher functional redundancy , because if we lose a species, another functionally similar one is there to take its place. All of these ideas have the basic meaning that stable ecosystems are capable of resisting change over time or bouncing back from disturbance.