China’s US $30 billion rubber industry, fueled by the demand for car tires, is seeing once-forested areas converted to vast rubber plantations.

As an article on Deutsche Welle shows, Xishuangbanna in the south of Yunnan province is one example. Most of this area used to be covered in diverse tropical forest, home to elephants and white-cheeked gibbons, but now one fifth of Xishuangbanna is planted with rubber. Farmers who used to struggle to grow enough rice and corn to survive now earn around US $27,000 per year.

Zhuang-fang Yi, a researcher at the World Agroforestry Centre, says rubber expansion has had a drastic effect on Xishuangbanna's trees, plants, soils and watersheds.

"Rubber monocultures have no other plants covering their surface and once the rains come it just washes away the topsoil," says Zhuang-fang.

"If there's no consideration of forest protection, then in the next 25 years Xishuangbanna is going to be much drier."

A study by the Asian Development Bank found that one hectare of rubber-plantation in Xishuangbanna loses more than 20 tons of soil to erosion each year. The plantations also lose more than a hundred tons of water as rain fails to penetrate the soil and refill groundwater tables.

There are some moves that could help reverse the situation. In 2012 the government announced a plan to convert under-performing rubber plantations back to natural forest. The plan also involves planting trees along stream beds to prevent erosion and restore animal habitats.

Read the full story: China's rubber boom obliterates southern forests