Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.

Aerial photo shows the Dongge Cuona Lake that locates at the source of Yellow River in Madoi County, Golak Tibetan Autonomous Prefecture, northwest China`s Qinghai Province begins to thaw as the temperature raises in April.