Application of AHP method in evaluation of water quality of Dianshan Lake in Shanghai City

The eutrophication of Dianshan Lake in Shanghai City threatens the ecology and environment in the lake region. On the basis of its monitoring results from 2005 to 2009,the eutrophication index system of Dianshan Lake was established by AHP method and the eutrophication situation was evaluated. The results showed that the water quality of the lake was in medium eutrophication. However,the water quality from 2005 to 2009 was improved with the decreasing of nitrogen and phosphorus. The evaluation method reveals the influential degree of every factor on eutrophication situation and the results are objective and reliable.