Farmers harvest highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

A farmer harvests highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

A farmer harvests highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

Farmers harvest highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

A farmer harvests highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

A farmer harvests highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

A farmer harvests highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

Farmers harvest highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)

A farmer harvests highland barley in the fields at Kaduo Village in Linzhou County, southwest China's Tibet Autonomous Region, Sept. 3, 2018. (Xinhua/Purbu Zhaxi)