Aerial photo taken on Nov. 4, 2020 shows workers collecting salt in a salt pond at Dongfeng salt field in Qingdao, east China's Shandong Province. Dongfeng salt field has entered the harvest season recently. (Photo by Liang Xiaopeng/Xinhua)

Aerial photo taken on Nov. 4, 2020 shows workers collecting salt in a salt pond at Dongfeng salt field in Qingdao, east China's Shandong Province. Dongfeng salt field has entered the harvest season recently. (Photo by Liang Xiaopeng/Xinhua)

Aerial photo taken on Nov. 4, 2020 shows workers collecting salt in a salt pond at Dongfeng salt field in Qingdao, east China's Shandong Province. Dongfeng salt field has entered the harvest season recently. (Photo by Liang Xiaopeng/Xinhua)

Aerial photo taken on Nov. 4, 2020 shows workers collecting salt in a salt pond at Dongfeng salt field in Qingdao, east China's Shandong Province. Dongfeng salt field has entered the harvest season recently. (Photo by Liang Xiaopeng/Xinhua)