Significant changes

As a photographer, Qi Hongyan has paid regular visits to Ulansuhai Nur since the 1980s.

The 66-year-old said he noticed that the local government had rolled out measures to remediate the lake in 2010, but little progress was made in the first few years.

When he passed the lake in 2012, he still saw a lot of dead fish floating on the surface, he recalled.

He said he saw some mild environmental improvements in the lake in the following years, but significant changes only occurred after 2020. Instead of being black, "the lake's water was green and clear" when he visited it more than two years ago.

"Before 2020, it was extremely difficult to see mute swans in the lake. Since then, though, there have been many, and the number of the birds is especially large this year," he said.

During one of his visits to the lake this year, Qi saw an island in the water that was "blanketed by birds", he said.

According to the Bayannuur government, the quality of the lake's water has been upgraded from below Grade V, the worst in the country's five-tier quality system for surface water, to Grade IV.

The number of birds around Ulansuhai Nur has also risen, with 264 species monitored at the lake recently, compared with 185 in 2000, it said. The number of mute swans living around the body of water has also climbed to more than 800 from roughly 200 in 2000.

Zhang Zhijia, a resident of Wayaotan, a village near Ulansuhai Nur, is keenly aware of the environmental improvements at the lake.

The overwhelming number of mosquitoes that made people avoid going outside in the evening as far as possible has fallen significantly as the water quality has improved.

"But the number of fish and shrimps has risen greatly," Zhang said with a smile.

Liu, the official with the Ulansuhai Nur administration, said he has found that swan geese, which disappeared from the lake as its environment deteriorated, are now returning in large numbers, indicating that the environment has greatly improved.

"We may not soon be able to see the water in the lake restored to the state it was in my childhood, when we could swim in the lake and directly use water from it for drinking and cooking, but definitely I think we are heading in that direction," he said.