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BiodiversityBiodiversity measurements

Biodiversity is the total variation between all living things and can be measured to help identify species that need to be supported. Threats to biodiversity have adverse effects on the ecosystem.

Part of BiologySustainability and interdependence

Biodiversity measurements

There are three measurable components of biodiversity:

  • genetic diversity
  • species diversity
  • ecosystem diversity

Genetic diversity

Genetic diversity relates to genetic variation of the number and frequency of alleles of a specific gene, as the image below illustrates.

Genetic diversity. The different coloured circles represent different alleles in the population. From this the number and frequency of alleles determines the genetic diversity of the population.

This image demonstrates genetic diversity. The different coloured circles represent different alleles in the population. From this the number and frequency of alleles determines the genetic diversity of the population.

If one population of a species dies out then the species may lose some of its genetic diversity. This may impact the species ability to adapt to changing conditions.

Species diversity

Species diversity is made up of two factors - the number of different species in an ecosystem and the proportion of each species in the ecosystem.

These represent the richness of the species and the relative abundance respectively. When a dominant species is present in a community it will have a lower species diversity than a community with the same species richness and no particularly dominant species.

Ecosystem

Ecosystem diversity is the number of distinct ecosystems in a defined area.

Biodiversity measurements can be used to monitor ecosystem change and for conservationists to decide on species to support.

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