Ningxia Hui autonomous region has been found to have illegal construction projects in nature reserves and insufficient implementation of pollution controls, the Ministry of Environmental Protection said on Wednesday.

Ningxia is the fifth provincial region to be inspected by a team sent by the central government. A total of 57 polluting companies have been shut down, while another 179 companies have been required to improve their equipment to control pollution. Eight people have been detained and 105 officials have been held accountable, inspectors said.

In the autonomous region, 149 illegal construction projects have been found inside the nine national-level nature reserves since 2013.

Among the 86 mining companies working inside the famous Helan Mountain National Nature Reserve, 81 have been open-cut mining, destroying the surroundings.

The ministry released results from inspection teams, which have conducted one-month inspections in eight provinces since mid-July.

Inspectors said Ningxia has prioritized economic growth over environmental protection, leading to degradation in certain areas.

Last year, government funds allocated to air pollution controls declined 58.4 percent year-on-year, while that allocated to water pollution controls fell by 40.6 percent.

The concentration of PM10 - particulate matter with a diameter of less than 10 micrometers - increased by 21.8 percent last year compared with 2013, and the region has failed to meet national targets for air pollution control since 2014, inspectors said.

Water in five of the eight major channels connecting to the Yellow River is so polluted that it is unfit for industrial, agricultural or public use.

Inspection teams have transferred more than 470 pollution-related cases to the government and required the autonomous region to submit plans to solve pollution issues to the State Council within a month.

zhengjinran@chinadaily.com.cn