Biodiversity: An index of intactness

The global community is committed to reducing the rate of loss of biodiversity, but how can progress be measured? A novel system to tackle the problem may also identify key factors behind the changes.Conservation begins at homeThe World Summit on Sustainable Development set the target of significantly reducing the rate of biodiversity loss by 2010. As yet there is no agreed way of measuring progress towards that goal. R. J. Schoels and R. Biggs of CSIR Environmentek, the environmental research facility based in Pretoria, South Africa, now offer a ‘biodiversity intactness index’ that might fit the bill. It focuses on changes in the population level of broad groups of species, rather than on extinction, which is hard to prove and provides warnings too late. The approach shows that most diversity exists outside formally protected areas, and that management of biodiversity in areas already used for agriculture, mining and habitation is key to slowing biodiversity loss.