Water Quality Characteristics and Fuzzy Comprehensive Evaluation on Qu River Basin
To accurately investigate the current situation and temporal-spatial distribution characteristics of water quality in the Qu River Basin,30 sampling sections containing DO,CODMn,NH3-N and TP were selected in this paper.Based on the monthly water quality data from 2021 to 2022,a comprehensive evaluation of water quality in the Qu River Basin was carried out with the fuzzy comprehensive evaluation method.The results showed that CODMn and TP were the main pollutants in the 30 sampling sections.The results of fuzzy comprehensive evaluation showed:93.3%of the sampling sections in Qu River Basin meet the Classes Ⅰ-Ⅲ water quality standards from 2021 to 2022;the water quality in the Qu River Basin was generally distributed between Classes Ⅰ-Ⅳ;the sampling sections of Class Ⅰ water quality were basically located in the upstream of the Qu River Basin;the sampling sections of Class Ⅳ water quality were located in the middle and lower streams;and the proportion of ClassesⅠ-Ⅲ water quality in 30 sampling sections in 2022 was increased by 3.3%,compared with that of 2021.The proportion of section s with the same results of the improved fuzzy comprehensive evaluation,fuzzy comprehensive evaluation and single factor index evaluation was between 83.3%and 90.0%.The results also showed that the improved fuzzy comprehensive evaluation method reflected the water quality evaluation results in highly polluted areas better,and its results were more stable.
Qu River Basinwater quality assessmentfuzzy comprehensive evaluation