Guilin is considered a pioneer in the country's tourism sector, as it is one of the first major Chinese cities to tap peak tourism waves, going back two decades. Guilin recorded nearly 19 million visitors in 2009, with the number surging to more than 80 million in 2017.

But the growth also threatened the Lijiang River environment. Rapid urbanization had already posed a threat to water quality, with local authorities recording about 175,000 metric tons of industrial and domestic sewage discharged into its waters each day as early as the 1970s, despite efforts to curb pollution.

Moves to promote green urban growth as well as the pillar tourism sector along the vital waterway are now reaping rewards. At the landmark Elephant Hill scenic area in central Guilin, tourists enjoy upgraded boats that take them on lake and river cruises.

"We've invested more than 46 million yuan to refurbish 39 cruise vessels, and injected 122 million yuan to build new ones. The vessels use green materials and power generation to stem emissions and reduce carbon footprints, with fuel consumption cut by 10 percent to 15 percent compared with ordinary diesel engines," said Li Feiying, head of the Guilin group that manages the tourism area.

Song Yongjun, 41, who captains the refurbished vessels taking visitors on tours, said the hardware is the best offered in his 17-year career.

"It's a big change from the more polluting vessels we used to have. They're better and safer now," Song said, adding that the improvements put them in good stead to handle renewed travel demand as the tourism sector looks beyond the difficulties of the COVID-19 pandemic.

Wang Zixi, director of the Guilin tourism bureau, said the city is poised to tap the latest opportunities and trends in the post-pandemic cultural tourism sector.

"We will integrate our resources with high-quality development, including the urban areas, building Guilin into a world-class scenic city," she said.

Fulongzhou, a major island on the Lijiang River, has become another model of Guilin's environmental inroads.

Covering more than six hectares, the island in the heart of the city used to be home to 23 households of more than 130 residents, with waste from restaurants that catered to visitors and from other daily activities discharged directly into the river, threatening the ecology and the safety of urban drinking water.

Five years ago, Fulongzhou's residents began to move off the island to better housing in the city as part of a drive to restore the area and turn it into public green space. The move has helped cut river discharge by at least 8 tons a year.

"In recent years, Guilin invested a total of 87 million yuan to implement and upgrade the comprehensive environmental management of Fulongzhou," said Guo Hongxing, head of the Lijiang River management committee. "The island has become an ecological park for the general public and tourists to be closer to the river and feel its beauty."