Beijing, December 19 (Youth.cn) - In a village in Taizhou, villagers were drying sweet potato bars in a sunny day. Guided by green development principle, the local authority encourage every village in its administration area to develop an industry that corresponds with local natural conditions. Xianju County, where sweet potatoes are planted, makes fully use of mountainous geographic condition to plant sweet potatoes and process them to snacks with local taste. The "sweet economy" has increased incomes to local households. Photo/VCG