Application of a New Improved Weighting Method, ESO Method Combined with Fuzzy Synthetic Method, in Water Quality Evaluation of Chagan Lake

Abstract

The existing weighting methods mainly comprise subjective and objective weighting and have a certain degree of subjectivity, with certain requirements for the professional ability of the users and unstable results. Therefore, an improved weighting method based on the entropy weight, over-standard multiple, and single-factor evaluation methods, referred to as the ESO method, is proposed. The advantages and advancements of the ESO method are demonstrated in this study by combining it with the fuzzy synthetic evaluation method to evaluate the water quality of Chagan Lake wetland from 2007 to 2016. The main conclusions of this study are as follows: 1. The ESO method has more comprehensive consideration factors, lower requirements for the professional ability of users, and more stable weighting results than the traditional weighting method. Therefore, it is highly suitable for beginners and frontline staff who are not professionally qualified and cannot accurately conduct subjective weighting. Meanwhile, owing to the amendment rule and emphasis on the local weight of the sample in the ESO method, it is applicable to time-series samples. 2. The ESO method better allocates the amendment weights to indicators with a higher degree of pollution; thus, the final comprehensive evaluation results are relatively conservative. However, in contrast to the single-factor evaluation, the conservatism of ESO method is the result of the comprehensive effect of all samples; thus, the conservative result of the ESO method is more reasonable. 3. The water quality of Chagan Lake in 2009 and 2015 was class IV, which did not meet the standard, while that in remaining the eight years was class III, which met the requirements of the national 13th Five-Year Plan. The results of this study can provide a new approach to weighting calculation methods and a basis for the protection and treatment of the ecological environment of the Chagan Lake wetland.

Constructing an Efficient Health Assessment Model for Drainage Network to Evaluate the Drainage Network in Zone A of Zhenjiang City

“…The usual range of confidence values is [0.5, 1], typically ranging from 0.6 to 0.7. In this article, 0.7 is chosen [36][37][38].…”

Multilevel Evaluation Model of Electric Power Steering System Based on Improved Combination Weighting and Cloud Theory

“…(3) Building comprehensive cloud parameters of the system Based on the above-weighted processing index cloud parameters, the cloud parameters of the entire EPS working state are summarized [20], and the specific calculation method is shown in Equation (15).…”

An assessment of the hydrochemical characteristics and nitrate human health risks of groundwater in a semi-arid plain: A case study of western Jilin Province

“…For example, Ding et al (Ding et al, 2022) combined the Analytic Hierarchy Process (AHP) and entropy weight method within an improved comprehensive water quality identification index; Yan et al (Yan et al, 2016b) used AHP, the entropy method, and coefficient of variation to combine subjective and objective weights within the establishment of a urban drinking water quality model. Zhao et al (Zhao et al, 2021) combined entropy weight and over-standard multiple and single-factor assessment methods within their proposed improved weighting method, which they combined with a fuzzy synthetic assessment method to evaluate the water quality of Chagan Lake. These studies have advanced the comprehensive weighting method and confirmed its feasibility.…”

“…Studies related to hydrochemistry have mainly focused on the migration, distribution and assessment of the risk to human health of harmful elements in groundwater, such as fluorine, arsenic, and cadmium (Adeyeye et al, 2021;Cao et al, 2009;Jianmin et al, 2015;Xu et al, 2020;Xu et al, 2021;Zhang et al, 2003), as well as on the evolution of hydrology and geochemistry (Li et al, 2019a). Recent groundwater quality assessments have mainly focused on Chagan Lake (Zhang et al, 2016b;Zhao et al, 2021), Songyuan City (Yan et al, 2021), and Songnen Plain (Chen et al, 2021). However, there remains insufficient knowledge on the hydrochemical characteristics, water quality, and risks posed to human health of nitrates of groundwater over the entire western plain of Jilin Province.…”