Aerial photo taken on Dec. 7, 2018 shows pond cypress trees and birds at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)

　　Aerial photo taken on Dec. 7, 2018 shows pond cypress trees and birds at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)

　　Aerial photo taken on Dec. 7, 2018 shows pond cypress trees and birds at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)

　　Photo taken on Dec. 7, 2018 shows pond cypress trees and birds at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)

　　Aerial photo taken on Dec. 7, 2018 shows pond cypress trees and a bird at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)

　　Photo taken on Dec. 7, 2018 shows pond cypress trees and a bird at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)

　　Photo taken on Dec. 7, 2018 shows pond cypress trees and birds at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)

　　Photo taken on Dec. 7, 2018 shows pond cypress trees and a bird at Chishan Lake National Wetland Park in the Lai'an County, east China's Anhui Province. The cypress trees not only curb water and soil erosion, but also attract various kinds of birds. (Xinhua/Zhang Duan)