Water Chemical Characteristics and Water Quality Evaluation of the River under the Ecological Water Replenishment: A Case Study in the Yongding River Basin in North China

Abstract

Ecological water replenishment projects have been implemented in the Yongding River (YDR) Basin since 2019 to adjust the contradiction between regional ecology and social development. To clarify the water chemistry, sources of riverine solutes, and the water quality assessment of the YDR under the ecological water replenishment, concentrations of major ions (Na + , K + , Ca 2+ Mg 2+ , SO 4 2− , HCO 3 − , Cl − , and NO 3 − ) of the YDR collected in August 2021 are determined. The dominant water chemical type of the YDR water was SO 4 2−•Cl − −Na + . Anthropogenic activities were the dominant factors affecting concentrations of riverine solutes, making up 71% of the total cations, and the main type was urban domestic sewage inputs. According to the evaluation of irrigation water quality, the YDR was facing a low-level sodium hazard and moderate salinity hazard, and the harm to soil aggregates was limited according to irrigation. The health threats to adult residents were limited in YDR, while potential health risks for children remained. Ecological water replenishment projects have been implemented to improve the ecological function of the YDR with significant effects observed near the replenishment outlets, leading to a significant improvement in the irrigation water quality. This study highlights the disturbance of ecological replenishment to water chemical characteristics and ecological restoration function to the dry-up river and provides a valuable example for further studies of water chemistry under ecological water replenishment.

Effects of Ionic Interferents on Electrocatalytic Nitrate Reduction: Mechanistic Insight

“…Therefore, the scope of our discussion is to address the impacts of ionic species in diverse water matrices, spanning groundwater, surface water, and industrial effluents. ,, The data collected from the reported literature (Figure a) show that surface water and groundwater are generally composed of similar types of co-existing ions. The NO 3 – concentrations in groundwater (∼0–250 mg/L) are slightly higher than those in surface water (∼0–150 mg/L) − as a result of the high infiltration and longer hydraulic retention time in groundwater. , The concentrations of Cl – ions are similar (∼0–200 mg/L) in surface water and groundwater. , The alkali and alkaline metals, including Na + , K + , and Ca 2+ , exhibit higher concentrations in groundwater compared to surface water, potentially as a result of mineral dissolution . In contrast, the mean values of SO 4 2– (85 mg/L) and HCO 3 – (190 mg/L) in surface water exceed those of 25 and 140 mg/L in groundwater, which may result from atmospheric precipitation and anthropogenic activities. − In addition, CO 3 2– is found in surface water at pH > 8 according to the carbonic acid pH–log C relationship.…”

“…The presence of co-existing ions that can significantly impact eNO 3 RR performance is one of the most important contributors to the uncertainties in implementing field-scale operations . Therefore, the scope of our discussion is to address the impacts of ionic species in diverse water matrices, spanning groundwater, surface water, and industrial effluents. ,, The data collected from the reported literature (Figure a) show that surface water and groundwater are generally composed of similar types of co-existing ions. The NO 3 – concentrations in groundwater (∼0–250 mg/L) are slightly higher than those in surface water (∼0–150 mg/L) − as a result of the high infiltration and longer hydraulic retention time in groundwater. , The concentrations of Cl – ions are similar (∼0–200 mg/L) in surface water and groundwater. , The alkali and alkaline metals, including Na + , K + , and Ca 2+ , exhibit higher concentrations in groundwater compared to surface water, potentially as a result of mineral dissolution .…”

Assessment and Comprehensive Evaluation of Large-Scale Reclaimed Water Reuse for Urban River Restoration and Water Resource Management: A Case Study in China

“…In recent years, there has been a growing interest in the application of reclaimed water reuse for urban river replenishment [9][10][11]. Studies have explored various aspects of this approach to assess its feasibility and potential benefits, including the technical aspects of water treatment, water quality analysis, hydrological modeling, and ecological assessments [12][13][14][15].…”