The expansion of rubber plantations in southeast Asia could have a "devastating" environmental impact, scientists warned Thursday as they pressed for a substantial increase in forest preserves.
More than 500,000 hectares (1.2 million acres) may have already been converted to rubber plantations in the uplands of China, Thailand, Vietnam, Laos, Cambodia and Myanmar.
And researchers predict the area of land dedicated to rubber and other farming systems could more than double or triple by 2050, replacing lands currently occupied by evergreen broadleaf trees and secondary vegetation growing in areas subjected to slash-and-burn farming.
That could result in a significant reduction in carbon biomass, dessicate the region's water systems, and increase the risk of landslides through erosion, researchers from China, Singapore and the US warned in an essay in the journal Science.
"The unrestricted expansion of rubber in montane mainland southeast Asia could have devastating environmental effects," wrote lead author Alan Ziegler of the National University of Singapore.
Ziegel and his colleagues warned "time is too short" to wait for results from studies aimed providing reliable assessments of the impact on water systems.
"A substantial increase in natural reserve areas could help to reduce the threats to biodiversity and carbon stocks," they wrote.
The authors also suggested promoting "diversified agroforestry systems in which cash crops such as rubber and oil palm play important roles, but are not planted as monocultures."
(c) 2009 AFP