This photo taken on March 11, 2018 shows saline fields in Mangkam County of Qamdo, southwest China`s Tibet Autonomous Region. Local salt farmers have followed a centuries-old harvesting method by collecting brines from the rocks and drying them in prepared fields until the salt within crystalizes. (Xinhua/Jigme Dorgi)

A salt farmer examines saline stalactites formed by trickling brines in Mangkam County of Qamdo, southwest China`s Tibet Autonomous Region, March 11, 2018. Local salt farmers have followed a centuries-old harvesting method by collecting brines from the rocks and drying them in prepared fields until the salt within crystalizes. (Xinhua/Jigme Dorgi)

This photo taken on March 11, 2018 shows saline fields and stalactites in Mangkam County of Qamdo, southwest China`s Tibet Autonomous Region. Local salt farmers have followed a centuries-old harvesting method by collecting brines from the rocks and drying them in prepared fields until the salt within crystalizes. (Xinhua/Jigme Dorgi)

A salt farmer works among patches of saline fields in Mangkam County of Qamdo, southwest China`s Tibet Autonomous Region, March 11, 2018. Local salt farmers have followed a centuries-old harvesting method by collecting brines from the rocks and drying them in prepared fields until the salt within crystalizes. (Xinhua/Jigme Dorgi)

A salt farmer works among saline fields in Mangkam County of Qamdo, southwest China`s Tibet Autonomous Region, March 11, 2018. Local salt farmers have followed a centuries-old harvesting method by collecting brines from the rocks and drying them in prepared fields until the salt within crystalizes. (Xinhua/Jigme Dorgi)

A salt farmer works among patches of saline fields in Mangkam County of Qamdo, southwest China`s Tibet Autonomous Region, March 11, 2018. Local salt farmers have followed a centuries-old harvesting method by collecting brines from the rocks and drying them in prepared fields until the salt within crystalizes. (Xinhua/Jigme Dorgi)