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PubMed · 15744293

A biodiversity intactness index.

R J Scholes·R Biggs
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Abstract

The nations of the world have set themselves a target of reducing the rate of biodiversity loss by 2010. Here, we propose a biodiversity intactness index (BII) for assessing progress towards this target that is simple and practical--but sensitive to important factors that influence biodiversity status--and which satisfies the criteria for policy relevance set by the Convention on Biological Diversity. Application of the BII is demonstrated on a large region (4 x 10(6) km2) of southern Africa. The BII score in the year 2000 is about 84%: in other words, averaged across all plant and vertebrate species in the region, populations have declined to 84% of their presumed pre-modern levels. The taxonomic group with the greatest loss is mammals, at 71% of pre-modern levels, and the ecosystem type with the greatest loss is grassland, with 74% of its former populations remaining. During the 1990s, a population decline of 0.8% is estimated to have occurred.

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Africa, SouthernAlgorithmsAnimalsBiodiversityConservation of Natural ResourcesData CollectionEcologyGeographyInternational CooperationMammalsPlant Physiological PhenomenaPopulation DynamicsSensitivity and SpecificityTime FactorsJournal Article

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R J Scholes, R Biggs. 2005-03-03. A biodiversity intactness index.. https://doi.org/10.1038/nature03289

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