Water quality status

China's Ministry of Environmental Protection "2015 China Environmental Status Bulletin" notified the water quality status of surface water, lakes and reservoirs, groundwater, coastal waters, and several important bays across the country
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Surface water mainly includes the seven major river basins of the Yangtze River, Yellow River, Pearl River, Songhua River, Huaihe River, Haihe River, and Liaohe River, as well as rivers in the Zhejiang-Fujian belt, northwestern rivers and southwestern rivers
.

Figure 1-1 Surface water quality in 2015

The proportion of national surface water sections with Grade I water quality in 2015 decreased by 0.

The main pollution indicators of 61 key lakes (reservoirs) in the country are total phosphorus, chemical oxygen demand and permanganate index
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Table 1-1 Water quality status of key lakes (reservoirs) in 2014

Figure 1-2 Lake (reservoir) water quality in 2015

Excessive groundwater indicators include total hardness, total dissolved solids, iron, manganese, "three nitrogens" ( nitrite nitrogen , nitrate nitrogen and ammonia nitrogen), fluoride, sulfate, etc.

Figure 1-3 Groundwater quality in 2015

The main pollution indicators in the coastal waters are inorganic nitrogen and active phosphate .

Figure 1-4 Water quality of coastal waters in 2015

In 2010, there were 69 red tides along the coast of China, with a cumulative area of ​​10892km ² , including 7 in the Bohai Sea with a cumulative area of ​​3560km ² ; 9 in the Yellow Sea with a cumulative area of ​​735km ² ; 39 in the East China Sea with a cumulative area of ​​6374km ² ; and 14 in the South China Sea with a cumulative area 223km ²
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The red tide frequent occurrence period in 2010 is from May to September, as listed in Table 1-2
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Table 1-2 Part of the red tide process with an area of more than 100km ² along the coast of China in 2010

The water quality of important bays in 2015 is shown in Figure 1-5
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Figure 1-5 Water quality of important bays in 2015