Finless porpoises - known in China as water pandas due to their rarity - have seen their numbers surge to about 1,000 in the Yangtze River thanks to improvement in water quality in the country's longest water body, Pan Biling, deputy head of Hunan province's environmental watchdog told reporters.

Pan, also a national political adviser, was answering questions from reporters at the Great Hall of the People in Beijing on Sunday afternoon.

He also said that Dongting Lake, a major water body connected to the Yangtze in Hunan, has seen the numbers of the porpoises rise to 110 from a record low of about 72.

The increase occurred amid water-improvement projects as the campaign to protect and restore the river's ecological environment goes on, Pan said.

The targets of the projects include tackling pollution from chemical plants along the river and wastewater discharge, said Pan.

Both central government bodies and governments in the provincial regions along the river have been paying more and more attention to the protection of the Yangtze since 2016, when President Xi Jinping highlighted ecological restoration and protection, as well as avoiding large-scale development near the river, he added.

He said the Ministry of Ecology and Environment and the National Development and Reform Commission, the country's top economic planner, published a circular on Yangtze restoration and protection early this year.

As part of the efforts by Hunan authorities, two three-year action plans have been carried out for the protection of the Xiangjiang River, a major tributary of the Yangtze, and more than 1,000 factories responsible for heavy metal pollution were shut down, Pan said.

As a result of the efforts from government bodies at various levels, national monitoring stations along the river last year found that 87.5 percent of the river's water has been at or above Grade III, the third highest in the country's five-tier water quality system, he said.

He stressed that the campaign for the Yangtze will be long, as there are still a lot of environmental violations occurring along the river. He said, however, he believes the country could win the campaign by emphasizing green development.