no area of china has supplied as much labor as sichuan, a fertile, mountainous region in the country’s southwest, home to pandas, bamboo forests, spicy cuisine and some of the country’s most difficult terrain, stretching west into the tibetan plateau and north toward the arid lands of gansu province.

　　sichuan also sits along one of asia’s biggest tectonic faults, making it prone to devastating earthquakes.when the chinese leader deng xiaoping, a native of sichuan, began pushing the country’s economic development in the 1980s, the government allowed poor people from farms and rural areas to move to big cities and coastal areas to work at factories and construction sites.

　　millions picked up and left sichuan. many have lived for years in cramped dormitories or temporary construction barracks, separated from their families, hoping to make enough to return home.li bo, 21, came to shanghai in 2004. he is from the city of mianyang in sichuan, northeast of the earthquake’s epicenter.his mother is safe, he says, but most of the rooms in his house have collapsed — the house the family spent thousands of dollars improving.

　　but he frets over a report from a relative that a huge lake called the bai shui has completely disappeared, apparently sucked down into the earth’s crust after the quake. could it be true, he wonders.“maybe the lake has disappeared forever,” he said. “this would be a disaster. the people would have grain but no water to boil things.”zhang shanghai, another 21-year-old sichuan resident working in shanghai, said he had reached his family. they had not yet heard from an uncle who had been working in a mine, and they were still tortured by tremors.“when i called my family yesterday, i heard the sound of heavy rain,” he said. “my uncle told me aftershocks are occurring every half hour and that his legs are shaking all the time, even in the safe periods.”

　　chen yang contributed research from tianjin, china.