Physics theory explains patterns of deforestation in the tropics
Scientists get a handle on sizes of forest fragments using percolation theory
Predicting rising numbers is usually good news in ecology, but not if they are forest fragments. Current rates of deforestation could cause a 33-fold increase in forest fragments over the next 50 years, shows a study published in Nature.
Deforestation, fuelled by factors including habitat conversion and timber production, causes fragmentation. As large forests are cut into pieces, biodiversity suffers and carbon is also lost. To study patterns of tropical forest fragmentation, scientists at the Helmholtz Centre for Environmental Research (Germany) used remotely-sensed images to map more than 130 million forest fragments across 427 million hectares in the Americas, Asia, Africa and Australia.
They found that fragment sizes in three continents followed similar frequency distributions. The number of forest fragments smaller than 10,000 hectares, for instance, is similar in Central and South America (11.2 %), Africa (9.9 %) and south-east Asia (9.2 %).
“This is surprising because land use noticeably differs from continent to continent,” said mathematician and lead author Franziska Taubert in a press release. While habitat conversion is what plagues the Amazon, it is logging of commercially-important forest trees in south-east Asia.