Comprehensive Evaluation of Surface Water Quality Based on SOM and PCA: A Case Study in Luan River Basin

Abstract Objective evaluation of surface water quality and quantitative analysis of water quality spatial characteristics are crucial for the sustainable utilization of surface water. This article innovatively proposes a method based on (Self-organizing maps) SOM, principal component analysis (PCA), and water quality index(WQIM) to evaluate the water quality of the Luan River Basin (LRB). Firstly, SOM an PCA were used to reduce the dimensionality characterize the hydrochemical characteristics of LRB, spatial variations, and establish the correlation between water quality indicators. In addition, a comprehensive evaluation the water quality of LRB monitoring sections through WQIM and quantify their water quality results. Then, SOM indicates that influencing factors of water quality were pH and TN (total nitrogen). PCA further validated the strong correlation between pH and TN. Finally, the comprehensive evaluation of LRB water quality was achieved using WQIM. This study qualitatively quantified the correlation between different water quality indicators, providing support for improving the accuracy of water quality evaluation.