China News Service, October 20. According to the WeChat official account of the Ministry of Ecology and Environment, the Ministry of Ecology and Environment announced on the 20th the state of surface water and ambient air quality throughout the country from September to September 2020.

In September, the average number of good days in 337 cities at prefecture level and above was 91.7%, an increase of 11.2 percentage points year-on-year; the PM2.5 concentration was 21 micrograms/m3, a year-on-year decrease of 19.2%.

Overall surface water conditions

　　In September 2020, among the 1940 national surface water assessment sections, the proportion of sections with good water quality (Class I-III) was 75.9%, an increase of 3.9 percentage points year-on-year; the proportion of sections with poor water quality was 2.1%, a year-on-year decrease of 1.7 percentage points.

The main pollution indicators are total phosphorus, chemical oxygen demand and permanganate index.

　　From January to September 2020, among the 1940 national surface water assessment sections, 81.2% of the sections with good water quality (Class I to III) were 81.2%, up 6.2% year-on-year; the proportion of sections with poor water quality was 0.8%, down 2.6% year-on-year .

The main pollution indicators are chemical oxygen demand, total phosphorus and permanganate index.

Water quality status of main rivers

　　In September 2020, the seven major river basins including the Yangtze River, the Yellow River, the Pearl River, the Songhua River, the Huaihe River, the Haihe River and the Liaohe River, as well as the rivers in the northwest, southwest and Zhejiang-Fujian rivers, had good water quality (class I to III). An increase of 3.4 percentage points; the proportion of sections inferior to Category V was 1.6%, a year-on-year decrease of 1.4 percentage points.

The main pollution indicators are chemical oxygen demand, permanganate index and total phosphorus.

Among them, the water quality of the rivers in the northwest, southwest and the Yangtze River is excellent, the rivers in Zhejiang and Fujian, the Yellow River and the Pearl River are of good water quality, and the Liaohe, Haihe, Huaihe and Songhua Rivers are lightly polluted.

Proportion of water quality categories in the seven major river basins and rivers in the southwest, northwest, and Zhejiang and Fujian regions in September 2020

　　From January to September 2020, the seven major river basins including the Yangtze River, the Yellow River, the Pearl River, the Songhua River, the Huaihe River, the Haihe River and the Liaohe River, as well as the northwestern, southwestern, and Zhejiang-Fujian rivers have good water quality (class I to III). The proportion of sections is 84.9% , A year-on-year increase of 6.3 percentage points; the proportion of sections with inferior grade V was 0.4%, a year-on-year decrease of 2.9 percentage points.

The main pollution indicators are chemical oxygen demand, permanganate index and total phosphorus.

Among them, the water quality of the rivers in the Northwest, the Yangtze River, the Southwest, the rivers of Zhejiang and Fujian, and the Pearl River are excellent; the water quality of the Yellow River and Songhua River are good; the Huaihe, Liaohe and Haihe rivers are lightly polluted.

Proportion of water quality categories in the seven major river basins and rivers in the southwest, northwest and Zhejiang and Fujian from January to September 2020

Water quality and nutritional status of important lakes (reservoirs)

　　In September 2020, among the 111 key lakes (reservoirs) monitored, the number of lakes and reservoirs with Grade I-III water quality accounted for 65.8%, an increase of 1.9% year-on-year; the number of lakes and reservoirs with water quality inferior to Grade V accounted for 4.5%, year-on-year A decrease of 2.9 percentage points.

The main pollution indicators are total phosphorus, permanganate index and chemical oxygen demand.

Among 106 lakes (reservoirs) monitored for nutritional status, 6 were moderately eutrophic, accounting for 5.7%; 26 were mildly eutrophic, accounting for 24.5%; the remaining lakes (reservoirs) did not show eutrophication.

Among them, Taihu Lake and Chaohu Lake are lightly polluted and mildly eutrophic, and the main pollution indicators are total phosphorus; Dianchi Lake is moderately polluted and moderately eutrophic. The main pollution indicators are chemical oxygen demand, total phosphorus and permanganate. Index; Erhai Lake and Danjiangkou Reservoir have excellent water quality and moderate nutrition; Baiyangdian Lake is lightly polluted and lightly eutrophic. The main pollution indicators are total phosphorus, chemical oxygen demand and permanganate index.

Compared with the same period last year, the quality of Erhai Lake has improved, and the nutritional status has not changed significantly. The water quality and nutritional status of Danjiangkou Reservoir, Baiyangdian Lake, Taihu Lake, Chaohu Lake and Dianchi Lake have not changed significantly.

　　From January to September 2020, among the 112 key lakes (reservoirs) monitored, the number of lakes and reservoirs with Grade I-III water quality accounted for 72.3%, an increase of 4.1% year-on-year; the number of lakes and reservoirs with water quality inferior to Grade V accounted for 5.4% , A year-on-year decrease of 1.9 percentage points.

The main pollution indicators are total phosphorus, chemical oxygen demand and permanganate index.

Among the 109 lakes (reservoirs) monitored for nutritional status, 1 lake (reservoir) with severe eutrophication, accounting for 0.9%; 6 with moderate eutrophication, accounting for 5.5%; 25 lakes with mild eutrophication, accounting for 22.9%; the remaining lakes ( Library) did not show eutrophication.

Among them, Taihu Lake and Chaohu Lake are lightly polluted and mildly eutrophic, and the main pollution indicators are total phosphorus; Dianchi Lake is moderately polluted and moderately eutrophic. The main pollution indicators are chemical oxygen demand, total phosphorus and permanganate. Index: Erhai Lake and Danjiangkou Reservoir have excellent water quality and moderate nutrition; Baiyangdian Lake is lightly polluted and lightly eutrophied. The main pollution indicators are chemical oxygen demand, total phosphorus and permanganate index.

Compared with the same period last year, the quality of Erhai Lake has improved, with no significant changes in nutritional status; Dianchi Lake's water quality and nutritional status have declined; Danjiangkou Reservoir, Taihu Lake, Chaohu Lake and Baiyangdian Lake have no significant changes in water quality and nutritional status.

National surface water assessment section ranking of cities at prefecture level and above

　　The cities at prefecture-level and above participating in the ranking cover 2050 state-controlled sections (of which 1940 are national surface water assessment sections and 110 are sea-controlled sections).

In September 2020, among the national prefecture-level and above cities, 30 cities including Turpan, Laibin, and Liuzhou have relatively good water quality in the national surface water assessment sections (from 1st to 30th), Cangzhou, Dongying and Xingtai The water environment quality of the national surface water assessment sections in 30 cities including the city is relatively poor (from the bottom to the bottom 30).

From January to September, among the prefecture-level and above cities in the country, 30 cities including Liuzhou, Zhangye, and Jinchang City have relatively good water environment quality in the national surface water assessment sections (from 1st to 30th), Tongchuan, Cangzhou and Xingtai The water environment quality of the national surface water assessment sections in 30 cities including the city is relatively poor (from the bottom 1 to the 30th); the water environment quality changes of the national surface water assessment sections in 30 cities including Yingkou, Luliang and Dongguan are relatively poor Good (from the 1st to the 30th), and the changes in the water environment quality of the national surface water assessment sections in 30 cities including Tongchuan, Changde and Chifeng are relatively poor (from the bottom 1 to the bottom 30).

Ambient air

　　In September, the average number of good days in 337 cities at prefecture-level and above was 91.7%, an increase of 11.2 percentage points year-on-year; the PM2.5 concentration was 21 μg/m3, a year-on-year decrease of 19.2%; the PM10 concentration was 42 μg/m3, A year-on-year decrease of 17.6%; O3 concentration was 134 μg/m3, a year-on-year decrease of 14.6%; SO2 concentration was 9 μg/m3, a year-on-year decrease of 10.0%; NO2 concentration was 22 μg/m3, a year-on-year decrease of 8.3%; CO concentration was 0.9 mg/cubic meter, unchanged year-on-year.

　　From January to September, the average number of good days in 337 prefecture-level and above cities across the country was 87.2%, an increase of 5.7 percentage points year-on-year; the PM2.5 concentration was 30 μg/m3, a year-on-year decrease of 11.8%; the PM10 concentration was 51 μg/m3 M, a year-on-year decrease of 15.0%; O3 concentration was 142 μg/m3, a year-on-year decrease of 6.6%; SO2 concentration was 10 μg/m3, a year-on-year decrease of 9.1%; NO2 concentration was 22 μg/m3, a year-on-year decrease of 12.0%; CO The concentration was 1.2 mg/m3, a decrease of 7.7% year-on-year.

Proportion of days of each level in 337 cities at prefecture-level and above across the country from January to September 2020

Concentrations and year-on-year changes of six indicators in 337 cities at prefecture-level and above across the country from January to September 2020

　　In September, the average number of good days in Beijing-Tianjin-Hebei and surrounding "2+26" cities was 74.2%, up 25.7 percentage points year-on-year; PM2.5 concentration was 31 μg/m3, down 16.2% year-on-year; O3 concentration was 180 μg /Cubic meter, a year-on-year decrease of 12.2%.

From January to September, the average number of good days was 62.8%, a year-on-year increase of 13.1%; the PM2.5 concentration was 48 μg/m3, a year-on-year decrease of 11.1%; the O3 concentration was 189 μg/m3, a year-on-year decrease of 6.9%.

　　The proportion of good days in Beijing in September was 90.0%, a year-on-year increase of 40.0%; the PM2.5 concentration was 24 μg/m3, a year-on-year decrease of 33.3%; the O3 concentration was 151 μg/m3, a year-on-year decrease of 29.1%.

From January to September, the proportion of good days was 71.9%, an increase of 11.5 percentage points year-on-year; the PM2.5 concentration was 39 μg/m3, a year-on-year decrease of 7.1%; the O3 concentration was 186 μg/m3, a year-on-year decrease of 9.7%.

　　The average number of good days in the 41 cities in the Yangtze River Delta region in September was 80.2%, an increase of 5.7 percentage points year-on-year; the PM2.5 concentration was 26 μg/m3, a year-on-year decrease of 3.7%; the O3 concentration was 180 μg/m3, which was the same year-on-year.

From January to September, the average number of good days was 85.4%, an increase of 10.2 percentage points year-on-year; the PM2.5 concentration was 32 μg/m3, a year-on-year decrease of 17.9%; the O3 concentration was 159 μg/m3, a year-on-year decrease of 7.0%.

　　The average number of good days in the 11 cities in the Fenwei Plain in September was 90.6%, a year-on-year increase of 11.5 percentage points; the PM2.5 concentration was 32 μg/m3, a year-on-year increase of 10.3%; the O3 concentration was 155 μg/m3, a year-on-year decrease of 9.4 %.

From January to September, the average number of good days was 71.5%, an increase of 12.1 percentage points year-on-year; the PM2.5 concentration was 44 μg/m3, a year-on-year decrease of 15.4%; the O3 concentration was 168 μg/m3, a year-on-year decrease of 6.7%.

　　In September, among the 168 key cities, the air quality of Anyang, Zibo, and Tangshan was relatively poor (from the bottom to the bottom 20); the air quality of cities such as Haikou, Ya'an, and Guiyang was relatively good (from 1st to tied for 19th).

　　From January to September, among the 168 key cities, the air quality of Tangshan, Shijiazhuang, and Taiyuan was relatively poor (from the bottom to the bottom 20); the air quality of cities such as Haikou, Lhasa, and Zhuhai was relatively good (From No. 1 to tied for No. 19).

The air quality changes in 20 cities including Baotou, Hohhot, and Harbin were relatively poor (from the bottom to the bottom 20); the air quality changes in 20 cities including Yichang, Jingzhou and Jingmen were relatively good (from 1st to tied for 19th).