Southern Yunnan is home to China's only tropical rainforest, but its existence is being threatened by rising rubber prices, which has spurred increased rubber planting in recent years.
Rubber planting has led to a 67 percent decline in Yunnan's tropical rainforest coverage in the last 30 years, according to a paper published in the first issue of the online journal Tropical Conservation Science by Dr Zhu Hua of the Xishuangbanna Tropical Botanical Garden, China Academy of Sciences.
"Rubber plantations, by replacing this unique type of tropical rainforest, are resulting in a loss of biodiversity," Zhu writes.
"The tropical seasonal rainforest in southern Yunnan conspicuously decreased from a cover of 10.9 percent of the total area of the region in 1976 down to 3.6 percent in 2003, mainly due to rubber planting. The high price of rubber has continued to promote the expansion of rubber plantations in the region."
There is no question that the rubber tree has brought new affluence to Xishuangbanna's poor rural farmers, who previously operated on a subsistence level. But the growing numbers of rubber plantations in the region are causing a loss of biodiversity. In Zhu's words:
"Limiting further expansion of rubber plantations is the only way to conserve the tropical seasonal rainforest in southern Yunnan."
The rubber tree has brought economic benefits to southern Yunnan, but it is creating other long-term problems that cannot be ignored. In addition to dwindling biodiversity, the thirsty rubber tree is also draining the area's water supplies. Pesticides used on rubber trees are also contaminating local reservoirs used by villages for drinking water.