A Revised Method of Surface Water Quality Evaluation Based on Background Values and Its Application to Samples Collected in Heilongjiang Province, China

Maoqing Duan,Wenqi Peng,Shijie Zhang,Linqing Yan,Xia Du

doi:10.3390/w11051057

Maoqing Duan, Wenqi Peng + Show 3 more

Open Access

https://doi.org/10.3390/w11051057

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Abstract

In China, the use of certain standards to evaluate surface water quality in areas with high background values due to natural factors rather than to human activities results in water quality underestimation and thus affects regional water quality management and decision-making. Herein, we examined river source water function zones of the Heilongjang province characterised by high background values and analysed the corresponding water quality data acquired in 2011–2016. The examined samples featured elevated chemical oxygen demand (COD), permanganate index (CODMn), and ammonia nitrogen (NH3-N) levels, which indicated that water quality was affected by the natural environment. The concentrations of background pollutants almost exceeded the limits stipulated by regional surface water quality standards and exhibited strong spatiotemporal variability. A three-step discrimination method including single index recognition, limiting factors, and a synthetic index was proposed to distinguish the background area among these zones for determining background values, and 10 complete background areas were identified. The background values of COD, CODMn, and NH3-N for the entire area were determined based on the data acquired during background area monitoring. Finally, considering the present procedure of water quality evaluation in China (single factor exponential method), a revised method based on background values was suggested. Thus, the evaluation results objectively and accurately reflect the regional water quality situation and therefore provide a scientific basis for the development of a better water quality assessment and management system in China.

Highlights

Since the 1960s, countries around the world have become increasingly concerned about environmental problems
Determining surface water geochemical background values is key for guiding environmental legislation, regional water resource protection, and managing the water quality of rivers
PH, total nitrogen, and faecal coliform bacteria contents are not involved in the them, water temperature, pH, total nitrogen, and faecal coliform bacteria contents are not involved in process of water quality evaluation, while volatile phenols, anionic surfactants, and total phosphorus the process of water quality evaluation, while volatile phenols, anionic surfactants, and total contents are monitored less than 150 times and less than the detection limit

Summary

Introduction

Since the 1960s, countries around the world have become increasingly concerned about environmental problems. Compared to soil and groundwater, determining surface water geochemical background values is difficult because of various factors influencing its complexity and variability (e.g., hydrologic and hydraulic conditions, the natural environment, and anthropogenic factors). Assessed each sampling location in terms of land use and other potential research on environmental background values based on monitoring data from the study area obtained anthropogenic influences onignored the determined metal background of surface water.area. [10] the assessed each sampling location in terms of land use and other potential areas anthropogenic influences on the determined metal background of surface water. Background pollution and regional characteristics are influence on water quality, and a three-step discriminant methodsources is proposed to identify the background considered to identify several natural and human factors that have a substantial influence on water areas (Figure 5)

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Conclusion