Aerial photo taken on Sept. 28, 2020 shows salt pans in Naxi Township of Mangkam County, Qamdo, southwest China's Tibet Autonomous Region. Local people follow a traditional salt harvesting method by collecting brines from salt mines and ponds and evaporating them in the sun until crystallization. (Xinhua/Zhan Yan)

Aerial photo taken on Sept. 28, 2020 shows salt pans in Naxi Township of Mangkam County, Qamdo, southwest China's Tibet Autonomous Region. Local people follow a traditional salt harvesting method by collecting brines from salt mines and ponds and evaporating them in the sun until crystallization. (Xinhua/Zhan Yan)

Aerial photo taken on Sept. 28, 2020 shows salt pans in Naxi Township of Mangkam County, Qamdo, southwest China's Tibet Autonomous Region. Local people follow a traditional salt harvesting method by collecting brines from salt mines and ponds and evaporating them in the sun until crystallization. (Xinhua/Zhan Yan)

Aerial photo taken on Sept. 28, 2020 shows salt pans in Naxi Township of Mangkam County, Qamdo, southwest China's Tibet Autonomous Region. Local people follow a traditional salt harvesting method by collecting brines from salt mines and ponds and evaporating them in the sun until crystallization. (Xinhua/Zhan Yan)

Aerial photo taken on Sept. 28, 2020 shows salt pans in Naxi Township of Mangkam County, Qamdo, southwest China's Tibet Autonomous Region. Local people follow a traditional salt harvesting method by collecting brines from salt mines and ponds and evaporating them in the sun until crystallization. (Xinhua/Zhan Yan)