The Relationship between Surface Water Quality and Watershed Characteristics

Abstract

The healthy water resources are necessary and essential prerequisite for environmental protection and economic development, political, social and cultural rights of Iran. In this research, water quality parameters i.e. total dissolved solids (TDS), sodium absorption rate (SAR), electrical conductivity (EC), Na+, Cl-, CO32-, K+, Mg2+, Ca2+, pH, HCO3- and SO42- during 2010-2011 were obtained from Iranian Water Resources Research Institute in water quality measurement stations on Mazandaran province, Iran. Then, the most important catchment characteristics (area, mean slope, mean height, base flow index, annual rainfall, land cover, and geology) were determined on water quality parameters using stepwise regression via backwards method in the 63 selected rivers. The results showed that sodium absorption rate (SAR), total dissolved solids (TDS), electrical conductivity (EC), Na+ and Cl- parameters are strongly linked to geology characteristics, while K+, Mg2+ and Ca2+ cations is linked to rainfall and geology characteristics. pH and HCO3- are related to area, rainfall, land cover and geology characteristics, CO32- is related to area, rainfall, rangeland area and geology characteristics and SO42- is related to area, rainfall, range and bar land area and geology characteristics. Adaptive Neuro-Fuzzy Inference System (ANFIS) was used for modeling the selected catchment characteristics and water quality parameters. The ANFIS models have a high Nash–Sutcliffe model efficiency coefficient (NSE) and low root mean squares error (RMSE) to estimate water quality parameters.

A comparative study of various parameters of drinking water quality in Shahroud city, Iran: tap water, well water and bottled water

“…In terms of hardness, brands 1, 2, 4, 6 and 7 had hardness values above the IBWA standard. Differences in the quality of various brands of bottled drinking water can be attributed to the quality of water purifiers or geographical differences in water resources, precipitation, mineralogy of aquifer rocks and regional topography, which provide water for bottled water companies (Mohammadi et al, 2019). In a study by Dindarloo in Bandar Abbas (Dindarloo et al, 2016), it was revealed that the quality of some parameters, such as pH, in some brands was not consistent with the standard.…”