A farmer drives past a sign with directions to the Dongtan Wetland, where Dongtan Eco City is planned to be built, on Chong Ming Island southeast to Shanghai in this January 21, 2008 file photo. Shanghai's Dongtan Eco-city has a lofty ambition: To become the world's first carbon-neutral city, just as recent estimates suggest that China has overtaken the United States as the largest emitter of globe-warming carbon dioxide. To match feature CHINA-ECOCITY/ REUTERS/ Nir Elias/Files (CHINA)
REUTERS/NIR ELIAS