Photo taken on Oct. 27, 2020 shows a hydroponic farm at a modern agricultural park in Tongshan District, Xuzhou, east China's Jiangsu Province. Authorities in Tongshan District have taken steps to optimize the local agricultural sector by combining modern agriculture with urban tourism. Altogether, the district's 300-plus agritourism parks have received some four million visitors in 2019. (Xinhua/Li Bo)