Combo photo including undated file photos (top and middle) and photo taken on June 28, 2018 (bottom) shows the Shimen Forest Park of the Qilian Mountains national nature reserve before, during and after its environmental restoration in Wuwei, northwest China's Gansu Province. The Qilian Mountains, on the border of Gansu and Qinghai provinces, was designated a national nature reserve in 1988. However, many illegal mining projects and hydropower stations have sprung up as a result of lax supervision in recent years, inflicting significant damage to the environment. Provincial authorities have revised local environmental protection regulations to ban production activities, including mining, in the core and buffer zones of the Qilian Mountains nature reserve. Other measures include closing hydropower stations and relocating herders in efforts to protect the national nature reserve. (Xinhua/Fan Peishen)

Lan Yonghua, a resident relocated from the Qilian Mountains nature reserve, takes care of sheep at home in Dongniumao Village of Zhangye, northwest China's Gansu Province, March 27, 2018. The Qilian Mountains, on the border of Gansu and Qinghai provinces, was designated a national nature reserve in 1988. However, many illegal mining projects and hydropower stations have sprung up as a result of lax supervision in recent years, inflicting significant damage to the environment. Provincial authorities have revised local environmental protection regulations to ban production activities, including mining, in the core and buffer zones of the Qilian Mountains nature reserve. Other measures include closing hydropower stations and relocating herders in efforts to protect the national nature reserve. (Xinhua/Fan Peishen)

Aerial photo taken on March 27, 2018 shows a view of the former site of Zhengnangou Village after it was moved out of the Qilian Mountains, in Zhangye, northwest China's Gansu Province. The Qilian Mountains, on the border of Gansu and Qinghai provinces, was designated a national nature reserve in 1988. However, many illegal mining projects and hydropower stations have sprung up as a result of lax supervision in recent years, inflicting significant damage to the environment. Provincial authorities have revised local environmental protection regulations to ban production activities, including mining, in the core and buffer zones of the Qilian Mountains nature reserve. Other measures include closing hydropower stations and relocating herders in efforts to protect the national nature reserve. (Xinhua/Fan Peishen)

Staff members check the environment monitoring system on the Qilian Mountains in Zhangye, northwest China's Gansu Province, June 5, 2018. The Qilian Mountains, on the border of Gansu and Qinghai provinces, was designated a national nature reserve in 1988. However, many illegal mining projects and hydropower stations have sprung up as a result of lax supervision in recent years, inflicting significant damage to the environment. Provincial authorities have revised local environmental protection regulations to ban production activities, including mining, in the core and buffer zones of the Qilian Mountains nature reserve. Other measures include closing hydropower stations and relocating herders in efforts to protect the national nature reserve. (Xinhua/Fan Peishen)

Photo taken on March 27, 2018 shows a view of the former site of Zhengnangou Village after it was moved out of the Qilian Mountains, in Zhangye City, northwest China's Gansu Province. The Qilian Mountains, on the border of Gansu and Qinghai provinces, was designated a national nature reserve in 1988. However, many illegal mining projects and hydropower stations have sprung up as a result of lax supervision in recent years, inflicting significant damage to the environment. Provincial authorities have revised local environmental protection regulations to ban production activities, including mining, in the core and buffer zones of the Qilian Mountains nature reserve. Other measures include closing hydropower stations and relocating herders in efforts to protect the national nature reserve. (Xinhua/Fan Peishen)

Aerial photo taken on June 20, 2018 shows the site of a closed mine in the Qilian Mountains national nature reserve in Jinchang, northwest China's Gansu Province. The Qilian Mountains, on the border of Gansu and Qinghai provinces, was designated a national nature reserve in 1988. However, many illegal mining projects and hydropower stations have sprung up as a result of lax supervision in recent years, inflicting significant damage to the environment. Provincial authorities have revised local environmental protection regulations to ban production activities, including mining, in the core and buffer zones of the Qilian Mountains nature reserve. Other measures include closing hydropower stations and relocating herders in efforts to protect the national nature reserve. (Xinhua/Fan Peishen)

Photo taken on June 5, 2018 shows staff members checking the flow of water at the Longshou hydropower station in the Qilian Mountains national nature reserve in Zhangye City, northwest China's Gansu Province. The Qilian Mountains, on the border of Gansu and Qinghai provinces, was designated a national nature reserve in 1988. However, many illegal mining projects and hydropower stations have sprung up as a result of lax supervision in recent years, inflicting significant damage to the environment. Provincial authorities have revised local environmental protection regulations to ban production activities, including mining, in the core and buffer zones of the Qilian Mountains nature reserve. Other measures include closing hydropower stations and relocating herders in efforts to protect the national nature reserve. (Xinhua/Fan Peishen)