A bird catches fish at Nanhu Park in Tangshan, north China's Hebei Province, July 15, 2019. Nanhu Park used to be a deserted spot due to coal exploitation. Since 1996, local authorities have taken measures to improve the environment. Over years of management, the park has been scenic spot with clean water and green trees. (Photo: Xinhua)

A bird catches fish at Nanhu Park in Tangshan, north China's Hebei Province, July 15, 2019. Nanhu Park used to be a deserted spot due to coal exploitation. Since 1996, local authorities have taken measures to improve the environment. Over years of management, the park has been scenic spot with clean water and green trees. (Photo: Xinhua)

A bird catches fish at Nanhu Park in Tangshan, north China's Hebei Province, July 15, 2019. Nanhu Park used to be a deserted spot due to coal exploitation. Since 1996, local authorities have taken measures to improve the environment. Over years of management, the park has been scenic spot with clean water and green trees. (Photo: Xinhua)

A bird is seen at Nanhu Park in Tangshan, north China's Hebei Province, July 15, 2019. Nanhu Park used to be a deserted spot due to coal exploitation. Since 1996, local authorities have taken measures to improve the environment. Over years of management, the park has been scenic spot with clean water and green trees. (Photo: Xinhua)

A bird rests on a seedpod of lotus at Nanhu Park in Tangshan, north China's Hebei Province, July 15, 2019. Nanhu Park used to be a deserted spot due to coal exploitation. Since 1996, local authorities have taken measures to improve the environment. Over years of management, the park has been scenic spot with clean water and green trees. (Photo: Xinhua)