River cleaners collect the floating objects at the Moshui River in Jimo District of Qingdao, east China's Shandong Province, April 5, 2020. Local authority of Jimo District in Qingdao has set up a river long-effect management mechanism to maintain the cleanliness of rivers. (Photo by Liang Xiaopeng/Xinhua)

People collect floating objects at the Moshui River in Jimo District of Qingdao, east China's Shandong Province, April 5, 2020. Local authority of Jimo District in Qingdao has set up a river long-effect management mechanism to maintain the cleanliness of rivers. (Photo by Liang Xiaopeng/Xinhua)

People collect floating objects at the Moshui River in Jimo District of Qingdao, east China's Shandong Province, April 5, 2020. Local authority of Jimo District in Qingdao has set up a river long-effect management mechanism to maintain the cleanliness of rivers. (Photo by Liang Xiaopeng/Xinhua)