More than 76,000 hectares of trees have also been planted, while water quality on the Jiangsu section of the Yangtze has stood at Grade II (the second-best level in China's five-tier water quality system) for five years, and no large-scale algal blooms have been reported in Taihu Lake for 15 years, the department said.

Yin Rongyao, the department's deputy director, said the province values environmental protection highly and has done a great job in ecological restoration despite facing enormous pressure and challenges.

"Jiangsu ranks among the top three provinces and municipalities nationwide for thermal power generation, steel and cement production. Its production of raw pesticide materials and dyes accounts for more than 40 percent of the total in China," Yin said.

"As the province with the smallest per capita land area in the country, the intensity of emissions from major pollutants per unit area is about five times that of the whole country."

He added that Jiangsu has closed more than 4,600 low-end chemical factories, 25 chemical parks and 57,000 polluting companies.

Meanwhile, the province's GDP has risen from 9.32 trillion yuan in 2018 to 12.29 trillion yuan last year.

The department said the annual average concentration of PM2.5 in Jiangsu has fallen by 33.3 percent in five years.

Last year, the PM2.5 concentration was 32 micrograms per cubic meter, marking the ninth consecutive year of decline, while the number of days with good air quality has risen by 5.2 percent in the past five years. Last year, 81.3 percent of days had good air quality in the 136 villages in which air quality monitoring was conducted.

Some 91 percent of surface water examined in a national monitoring program in Jiangsu last year stood at or above Grade III, which means it is suitable for people to drink or raise aquatic products. No areas of surface water were classified as Grade V, which is only good for use in farmland.

"The level of environmental satisfaction among the public in Jiangsu has risen for five consecutive years, reaching 93.6 percent in 2021," Yin said.