Fishing farms used to be nothing strange in the upper reaches of Xin'an River. With very little arable land per capita there, the river, which runs through Anhui and Zhejiang provinces, was what natives depended on for a living.
"More than a decade ago, the waters close to the shore were dotted with net cages for fish farming," recalled 55-year-old Wu Bin, a resident of Miantan village in Anhui's Shexian county.
While offering villagers a stable income, these fishing farms were heavily polluting the water body that locals refer to as "mother river".
The lack of garbage disposal facilities made the situation even worse. In the flood season, thousands of metric tons of garbage floated downstream, and this led in 2010 to an abnormal bloom of blue-green algae in Qiandao Lake in Zhejiang.
Things have changed now. People can directly source water from the river for drinking, thanks to a cross-region mechanism the two provinces introduced in 2012. The model encourages upstream stakeholders to implement pollution control measures and, in return, receive compensation from downstream areas for their efforts.
Under the system, the water that flows from Anhui to Zhejiang is subject to periodic assessments. If the quality reaches agreed standards, Zhejiang compensates Anhui for expenses incurred to protect the environment. Otherwise, Zhejiang is compensated to subsidize its additional costs to treat polluted water.
According to Anhui authorities, nearly 6,400 net cages owned by more than 3,000 fishermen were removed in the province, the annual output value of which totaled to roughly 40 million yuan ($5.7 million).
Besides compensation for their businesses, these fishermen were also given vocational training, so they could find new jobs. Many were encouraged and supported to take up eco-agriculture and tourism businesses.
Wu, from Miantan, for example, was offered job as a conductor for public transport vessels. "I make around 4,000 yuan a month," he said.
Some fishermen from his village now work at a local tourist attraction, where they demonstrate their skills at catching fish, Wu said. Others have opened rural resorts for tourists.
In 2019, the per capita income in the village of more than 2,000 residents had reached 15,000 yuan, which is above average in Anhui province.
According to Anhui's finance department, the province has received a total of 5.7 billion yuan of ecological compensation in the past 10 years.
With the help of the funds, Huangshan, which has over 60 percent of the about 373-kilometer Xin'an River, has done a lot more than just removing fishing farms. The city has shut down 220 polluting companies and relocated another 110, according to local authorities.
The city also introduced reward points in 2016 to encourage public participation in environmental protection. A person can win a point by collecting five spent batteries or 30 cigarette packages. Two points can be exchanged for a package of salt and four points for a bottle of detergent at 345 special supermarkets across Huangshan.
Yu Zhujin has frequented one of these supermarkets, in Qiankou village, Shexian county. At first, the 68-year-old was drawn by the rewards. "Now, it has become a habit. When I see discarded items outside, I pick them up to curb littering, not for points," she said.
Local authorities say that on average, each of the special supermarkets can annually recycle 190 kilograms of plastic bottles, almost 9,600 plastic bags and 415 kilograms of cigarette packages.
The cross-region eco-compensation mechanism is paying rich dividends, according to the Ministry of Ecology and Environment. "There has been significant progress in water pollution management in the Xin'an River Basin," it said.
Generally, the quality of water in the river is stable at Grade II. Some of the monitoring parameters can even reach Grade I, it said. China has a five-tier quality scale for surface water, Grade I being the best.
The ministry said the compensation model had also greatly boosted the green transition in Anhui.
The mechanism has been put into practice in 18 provincial regions across the country, which concerns 13 rivers, it said. Thirty-one provincial regions have introduced the system within their borders, and 13 of them have seen it cover all their major water bodies.
"The cooperation between the upstream and downstream regions is a win-win situation," the ministry added.
XINHUA contributed to this story.