A pair of egrets roost in the Zhanghe River in Northwest China's Gansu province. [Photo by Ma Tianyun]

Spring has arrived in Gansu, with lush meadows, beautiful flowers, chirping birds as its harbingers.

Zhangxian county of Dingxi, Northwest China's Gansu province, with its clean and green environment, is a retreat for fun-loving birds.

Flocks of snowy egrets seem happy creating humorous scenes with their human friends!

In recent years, the county has made continuous efforts to make progress in the battle to keep skies blue, waters clear and land pollution-free. Statistics show that Zhangxian has good air quality more than 97 percent of the time.