European scientists studying tropical forest deforestation around the world say it happens in “waves,” with highest-value timber being removed in a first wave.
An international team of researchers says economics drives each succeeding wave, with high-value trees being in the first “wave,” followed by a wave that removed mid-value timber before the remaining wood was felled for charcoal, the BBC reported Monday.
“This translates to a prediction that waves of forest degradation will emanate from major demand centers and expand into nearby forested areas, targeting resources in sequence, starting with those of highest value,” a study printed in the Proceedings of the National Academy of Sciences said.
The team says the deforestation model could help manage forests as vital carbon sinks and limit the loss of biodiversity.
The team used data collected around Tanzania’s largest city, Dar es Salaam, to see how far the degradation “waves” traveled between 1991 and 2005.
“The first wave that emanates is high-value timber, and that is mostly used for export,” Antje Ahrends of the Royal Botanical Garden, Edinburgh, said. “There has been a massive demand for this in China, and this is where most of the timber ends up.”
The second wave saw medium-valued timber trees being felled, generally used in the city for construction and furniture.
“This is expanding very rapidly, in line with urban migration,” she said. “The town has an average growth rate of about 7 percent each year, so there is — again — a rapidly growing demand for this material.”
The third and final wave involved local people collecting wood to make charcoal for cooking.
“It’s the most destructive of all of the waves because charcoal burners would collect everything,” Ahrends said.