Species richness:
number of species in an area is the usual measure of "biodiversity".
- Census indicator taxa because richness of one taxon will predict richness of another
Problems with this approach:
- Assumes that all species are equal: e.g. saving 5 species of Dichrostachys is as important as saving a conifer, a monocot, a dicot, a fern, and an alga
- Is a positive correlation between range size and abundance. Means that if you do rapid assessment methods will just be counting most widespread and abundant species.