A yak grazes on a mountain slope in autumn in Maizhokunggar county, southwest China's Tibet Autonomous Region, Oct. 11, 2014. (Xinhua/Wen Tao)

Yaks run on the field in autumn in Gongbo'gyamda county, southwest China's Tibet Autonomous Region, Oct. 11, 2014. (Xinhua/Wen Tao)

Yellow leaves fall on a road in autumn in Gongbo'gyamda county, southwest China's Tibet Autonomous Region, Oct. 11, 2014. (Xinhua/Wen Tao)

A yak walks near a golden forest in autumn in Gongbo'gyamda county, southwest China's Tibet Autonomous Region, Oct. 11, 2014. (Xinhua/Wen Tao)

Yellow leaves are seen on trees in autumn on the outskirts of Lhasa, capital of southwest China's Tibet Autonomous Region, Oct. 11, 2014. (Xinhua/Wen Tao)

Birds fly in front of the colorful autumn leaves in Maizhokunggar county, southwest China's Tibet Autonomous Region, Oct. 11, 2014. (Xinhua/Wen Tao)