Author(s): Mobina Hadinejad; Kumars Ebrahimi; Alireza Moghaddam Nia

Linked Author(s):

Keywords: Dissolved oxygen; Empirical modelling; Hybrid approaches; Jajrood River; River monitoring; Water quality assessment structure

Abstract: The Jajrood River is one of the vital surface water resources of Northern Iran, which provides drinking and agricultural water. Various sources of pollution have caused a decrease in dissolved oxygen (DO) concentrations along the above-mentioned river. This posing serious threats to water quality and aquatic ecosystems. This study conducted a comprehensive comparative evaluation of multiple dissolved oxygen assessment methods including: analytical, numerical, empirical, and data-driven modelling approaches. Also, field monitoring and water sampling were performed along the river to measure DO concentrations alongside associated water quality parameters including BOD₅, temperature, pH, and Nutrients. The performance of the aforementioned methods was evaluated along the river under different hydrological and pollution conditions. Different statistical criteria were used to assess the performances of the evaluated models. Results demonstrated that empirical relationships exhibited superior accuracy in capturing the complex DO dynamics influenced by both point and non-point pollution sources. Advanced hybrid approaches showed enhanced predictive capabilities, particularly in handling non-linear temporal patterns and multi-source hydro-meteorological data characteristic of river systems. Empirical models, when appropriately calibrated, provided the most reliable results for operational DO assessment.

DOI:

Year: 2026