China's environmental pollution situation and countermeasures
In 2006, among the 408 monitoring sections of 197 rivers in the seven major river systems of the Yangtze River, the Yellow River, the Pearl River, the Songhua River, the Huaihe River, the Haihe River and the Liaohe River, the sections of Class I to III, Class IV to V, and the sections inferior to Class V water quality accounted for 46%, 28%, and 26% respectively. The main pollution indicators are permanganate index, petroleum and ammonia nitrogen. In general, the water quality of the main stream is better than that of the tributaries, and the general river reach is stronger than that of the urban river reach. The pollution is gradually transferred from the downstream area to the upstream. In 2008, the water quality of the seven major river systems of the Yangtze River, the Yellow River, the Pearl River, the Songhua River, the Huaihe River, the Haihe River and the Liaohe River remained the same as in 2007.
