The order of the pollution for serious level to light level in the seven key river systems in 2001 is: Hai River,Liao River,Huai River,Huang River,Song Hua River,Yangtze River and Pearl River.

• 2001年，七大水系污染由重到轻的顺序依次是：海河、辽河、淮河、黄河、松花江、长江和珠江。