Farmers help villager Peng Qiugen harvest rice on the roof of Peng's house which had been converted into a rice field at Qilin Village of Shaoxing City, east China's Zhejiang Province, Nov. 18, 2013. Peng several years ago transformed the roof of his house into a farmland, in which rice, watermelons and vegetables have been harvested in different seasons. (Xinhua/Xu Yu)

Farmers help villager Peng Qiugen harvest rice on the roof of Peng's house which had been converted into a rice field at Qilin Village of Shaoxing City, east China's Zhejiang Province, Nov. 18, 2013. Peng several years ago transformed the roof of his house into a farmland, in which rice, watermelons and vegetables have been harvested in different seasons. (Xinhua/Xu Yu)

A farmer helps villager Peng Qiugen harvest rice on the roof of Peng's house which had been converted into a rice field at Qilin Village of Shaoxing City, east China's Zhejiang Province, Nov. 18, 2013. Peng several years ago transformed the roof of his house into a farmland, in which rice, watermelons and vegetables have been harvested in different seasons. (Xinhua/Xu Yu)