Abstract:

In view of the diversity of the water quality evaluation and incompatibility of evaluating results given by single index, the authors establish the groundwater quality evaluation model using the matter-element and extension method. As an example, the authors conduct a comprehensive evaluation of groundwater quality to the shallow groundwater in Lishu plain areas. Through the calculation of the integrated degree of association and extension index, the results show that the groundwater has been polluted along the riverside of Dongliao River, such as Gujiazi, Donghe, Jinshan and so on. In some other areas, the groundwater quality is deteriorating from Ⅱ to Ⅲ rank. By comparing the matter-element and extension means with the method of synthetically comparisons,  the reliability of the evaluation model is verified , and shows that using matter-element and extension means to evaluate the groundwater quality not only can reflect the overall situation of groundwater quality objectively, but also can analyze the deteriorating direction of water-quality sample. So, the matter-element and extension means can make the results of the evaluation closer to the actual situation.

Key words: water-quality evaluation, matter-element and extension, shallow groundwater