Professor Jeff Bennett
Asia Pacific School of Economics and Government
The Australian National University, October 2003
2. What is biodiversity?
The casual observer may be excused for thinking that biodiversity is synonymous with all things ‘natural’ and worth caring for in the environment such is the generality with which the term is used. Protecting biodiversity is a frequent call to arms within conservation non-government organization and features prominently in government policy documents as a goal. The definition of biodiversity is to the contrary, rather specific. It is, according to the United Nations Convention on Biological Diversity, the “… variability among living organisms”. Hence, the term relates specifically to variability rather than to the overall extent of the biological resource.
This variability can be considered at four levels:
- Genetic (ie genes, nucleotides, chromosomes, individuals);
- Species (ie kingdom, phyla, families, subspecies, species, populations);
- Ecosystem (ie bioregions, landscapes, habitats); and,
- Functional (ie ecosystem robustness, resilience, goods and services).
Hence, the term can be applied to the variability of genetic material through to landscape diversity.
It is also important to recognise that variability and overall magnitude are intrinsically linked. It is conceivable that genetic variability could be protected in intensively managed small-scale facilities such as zoos and herbariums and that mini landscape preserves could be established to provide representations at the ecosystem level. But to ensure resilience and robustness at the functional level it is difficult to imagine a protection regime that does not involve scale as well as diversity. For instance, resilience implies an ability to recover from an externally imposed shock. Almost by definition, a small-scale attempt to protect biodiversity will be at greater risk from an external shock. Even at the genetic and species levels, the protection of variability in the biological resource is afforded by larger scale protection initiatives. Put simply, scale and variability in the biological resource are likely to be strongly complementary.
It is, perhaps, because of this complementarity that biodiversity has taken on such an extensive mantle in the nature conservation debate.