Calculation and Analysis of Water Environmental Capacity of Typical Rivers in the Loess Area of Northern Shaanxi Based on a One-Dimensional Water Quality Model

DOI: https://doi.org/10.62517/jlsa.202607208

Author(s)

Qian Huang1,*, Pu Zhang1, Yuan Zhang1, Xiaohu Du2, Chunxing Guan1, Xiaokun Xu1, Lu Zhang1, Bo Yang1

Affiliation(s)

1Shaanxi Modern Architectural Design and Research Institute Co., Ltd., Xi'an, Shaanxi, China 2Huoqi County Water Resources Bureau, Lu'an, Anhui, China *Corresponding Author

Abstract

Water environmental capacity (WEC) is a key indicator for pollutant load control and watershed management. Taking the Xingzi, Xichuan, and Pingqiaochuan rivers in Ansai District, Yan’an City as case studies, this study selected COD, NH₃-N, and TP as control indicators and applied a one-dimensional water quality model based on GB/T 25173–2010 to estimate WEC under wet (10%), normal (50%), and dry (90%) hydrological years. Results showed that all three rivers maintained surplus WEC and generally good water quality. WEC followed the pattern of wet year > normal year > dry year and was significantly higher in summer than in winter. Among the rivers, Xichuan River had the largest WEC, followed by Xingzi River, while Pingqiaochuan River had the smallest. It is recommended that dry-year WEC be adopted as the baseline for total pollutant load control, with strengthened management of rural non-point source pollution and improved dry-season monitoring and early-warning systems. This study provides scientific support for regional water environmental management and pollutant control.

Keywords

Water Environmental Capacity; Water Quality Model; Design Hydrological Conditions; Non-Point Source Pollution; Loess Plateau

References

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