Comparison of Identification Methods of Main Component Hydrochemical Anomalies in Groundwater: A Case Study of Liujiang Basin

Abstract

Identification of chemical composition anomalies in groundwater is an important basis for establishing groundwater background values and quantifying the degree of influence of human activities. The main component anomaly identification by five kinds of hydrochemical diagrams has achieved good results in the past. However, this method is too complex to be used widely. In order to simplify the five kinds of hydrochemical diagrams, the Durov diagram was used to replace the five kinds of hydrochemical diagrams to identify the main component anomalies of groundwater, with the Liujiang basin employed as a verification example. The effects of seven kinds of anomaly identification methods combined by hydrochemical diagrams and mathematical statistics methods were compared, and the reliability of these methods were tested in the study. The result indicated that the combination of mathematical statistics and hydrochemical diagrams method can identify the groundwater anomalies better than either used alone. The method of the Pauta criterion+five kinds of hydrography diagrams and the Pauta criterion+the Durov diagram were the best to identify the major component anomalies of groundwater. This shows that the Durov diagram can effectively replace the five kinds of hydrochemical diagrams for anomaly recognition of groundwater, which not only preserves the scientificity of hydrochemical anomaly identification, but also greatly simplifies the process of calculation.