Slash-and-burn agriculture may be bad for the environment, but in southeast Asia, the cure may be worse than the disease. Endorsed by multiple governments, at both the local and national levels, as well as numerous business interests, everyone from individual farmers to massive corporations has been replacing the traditional slash-and-burn, more technically known as swidden, method of farming with rubber plantations managed with European techniques.
In the last 20 years, over 1.2 million acres of land in China, Thailand, Vietnam, Laos, Cambodia, and Myanmar have been cleared and replanted with nothing but rubber trees. By 2050, this number is expected to double — possibly even triple.
With international encouragement, Cambodia, Laos, and Thailand have halted swidden agriculture with laws that either criminalize the practice or make it otherwise unprofitable. Rubber plantations legally count in these areas as reforestation and are thus encouraged instead, and the growing appetite for tires in China has only added to both the market demands and the financial incentives. China already surpassed American demand for rubber in 2002 and is projected to consume 30% of the world supply by 2020.
But the outlook is even bleaker than the severe reduction in biodiversity would imply. Last week, an article appeared in Science outlining the dangers of such single-minded agribusiness. “The unrestricted expansion of rubber in montane mainland southeast Asia could have devastating environmental effects” according to lead author Alan Ziegler, a professor at the National University of Singapore who studies hydrology and geomorphology in southeast Asia. The growing rubber plantations, in reducing biodiversity, could significantly impact the region’s carbon biomass.
What is more, Jefferson Fox, one of Ziegler’s coauthors, believes that the rubber trees, transplants from South America and thus not native to the region, suck up the most water at the beginning of the monsoon season — when the soil is at its driest. The strain the trees will put on the already stressed water tables in these areas could lead to water shortages and even landslides due to eventual erosion.
From a purely economic perspective, other problems are lurking on the horizon. And a few are already here and entrenched. Economists warn that entrusting so many people’s livelihoods to a single crop could spell doom in future. After all, commodities markets are notoriously unstable, and cash crops themselves can suffer any number of environmental trials and tribulations — from droughts to floods to pests. The boll weevil infestation that decimated cotton crops in the southeastern U.S. in the early part of the 20th century is a testament to the far-reaching severity of Mother Nature’s more unpleasant surprises.
While the rubber business in Asia is currently highly lucrative — more so than rice and only slightly less so than opium — regulation is spotty and poor at best — and nonexistent at worst. Corruption within local governments, particularly among low-paid local officials is rife, and corporations are taking advantage of many local farmers.
The authors of the Science article assert that more diversified agricultural models might ameliorate some if not all the concerns created by this over farming. They state that more research is necessary to confirm their suspicions but add that the region’s environment may not have the luxury of the time required to conduct such studies. Either way, their own work ended abruptly due to a new Chinese policy preventing foreigners from collecting meteorological data, and they do not hold out much hope that the governments within the region will change anytime soon. As Fox said, “We can report that this is not a good trend for the environment and for people’s livelihoods, but I don’t think it’s going to stop.”