Aerial photo taken on Jan. 7, 2020 shows a freight train passing the Qingshiya Railway Station on the top of Qinling Mountains in Baoji City, northwest China's Shaanxi Province. (Xinhua/Tao Ming)

Xi Jinping, general secretary of the Communist Party of China Central Committee, on Monday urged local officials to be guardians of the ecological environment of the Qinling Mountains during his inspection tour in northwest China's Shaanxi Province.