From the BBC:
More than 10% of China’s farm land is polluted, posing a “severe threat” to the nation’s food production, state media reports.
Arable land shrank by nearly 307,000 hectares (760,000 acres) in the first 10 months of 2006, government officials were quoted as saying.
Excessive fertiliser use, polluted water, heavy metals and solid wastes are to blame, the reports said. [Full text]