Defining and measuring biodiversity
DownloaD Graphic 2
Biodiversity as defined by the Convention on Biological Diversity encompasses a natural state. For example, if a forest is cleared, then the MSA is based on
the diversity of genes, species and ecosystems. One terrestrial measure of the surviving forest species. MSA is modelled on a relative scale from 0 per
species-level diversity is the average remaining abundance of each individual cent (ecosystem destroyed) to 100 per cent (ecosystem intact).
species belonging to an ecosystem, or “mean original species abundance”
(MSA). MSA represents the remaining abundance of native species, relative to
Mean species abundance in 2000
Mean species abundance index (2000)
< 50%
50–60%
60–70%
70–80%
80–90%
90–100%
DownloaD Graphic 2
36 VITAL GEO GRAPHICS