But now, researchers writing in Tropical Conservation Science journal have revealed that biodiversity can also be affected when humans move away.
Aerin Jacob, a biologist at McGill University in Canada, and her team discovered that as people leave an area, one dominant habitat (usually secondary forest or savannah) comes to take over from the diverse mosaic of human-maintained landscapes.
This ‘ecological homogenisation’ can lead to a decrease in biodiversity at a local level, the scientists concluded, although this will not be the case everywhere.
‘We need to understand the social, biological and economic reasons behind rural depopulation if we want to conserve biodiversity and help rural people deal with declining populations,’ Jacob said. ‘Globally, the situation is complex. Rural depopulation and the resulting environmental changes will not happen everywhere. Nor does a decrease in habitat diversity necessarily imply conservation losses.’
This article first appeared in the Ecologist January 2009
