The Application of Extension Engineering Method in Water Environmental Quality Evaluation

The water environmental quality assessment is the most important content in the environmental quality evaluation. And the environmental quality assessment depends on the scientific assessment methods. The extension method is a new method which resolves the contradictory problem in the real world from two angles of the qualitative and quantitative. The paper introduces emphatically the application of the assessment of extension engineering method in the water environment and carries on the comparison with fuzzy assessment method which is the most widespread and whose appraisal effect is very well. The result indicates that the extension engineering method has a very good prospect for development with its unique thought model - matter-element model in the environmental quality evaluation.