Improving surface water quality of the Yellow River Basin due to anthropogenic changes

Jinling Quan; Yuxuan Xu; Ting Ma; John P Wilson; Na Zhao; Yong Ni

doi:10.1016/j.scitotenv.2022.155607

Improving surface water quality of the Yellow River Basin due to anthropogenic changes

Sci Total Environ. 2022 Aug 25:836:155607. doi: 10.1016/j.scitotenv.2022.155607. Epub 2022 Apr 29.

Authors

Jinling Quan¹, Yuxuan Xu¹, Ting Ma², John P Wilson³, Na Zhao¹, Yong Ni⁴

Affiliations

¹ State Key Laboratory of Resources and Environmental Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² State Key Laboratory of Resources and Environmental Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China. Electronic address: mting@lreis.ac.cn.
³ Spatial Sciences Institute, College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA 90089, USA.
⁴ China National Environmental Monitoring Center, Beijing 100012, China.

PMID: 35500708
DOI: 10.1016/j.scitotenv.2022.155607

Abstract

Understanding of how changes in diverse human activities and climate contribute to water quality dynamics is crucial for sustainable water environment management especially in the arid and semi-arid regions. This study conducted a comprehensive estimation of the surface water quality change in the Yellow River basin during 2003-2017 and its responses to varied pollution sources and water volumes under socioeconomic and environmental influences. Basin-wide measurements of chemical oxygen demand (COD), ammonium nitrogen (NH⁺₄-N) and dissolved oxygen (DO) concentrations were used in trend detection. Annual anthropogenic (covering six sectors) and natural (sediment-induced, flow-in from the upstream and stored last year) pollution sources and water components (inflow, natural runoff, water consumption, reservoir storage and evaporation) were compiled for each sub-basin. Bottom-up hierarchical analysis was then performed to differentiate individual contributions. Results showed significant decreasing trends in COD and NH⁺₄-N concentrations and increasing trends in DO concentrations. The middle reaches that traverse the Loess Plateau however remained severely polluted with 11.3-39.0% inferior to level III in 2017. The pollutant load played major positive contributions that gradually increased from upper to lower reaches. Declines in urban, rural and industrial pollution discharges following environmental investments and rural depopulation contributed the most: 78-96% for COD and 55-100% for NH⁺₄-N. The total surface water volume had dilution effects in the upper and middle reaches (3-28%) and condensing effects in the lower reaches (2-37%). Precipitation and vegetation dynamics contributed slightly. The primary unfavorable factors were the growing agricultural pollution discharges and water consumption in the upper and middle reaches that also threatened the lower reaches. This study is expected to provide in-depth insights for the systematic response of regional water quality to combined human interventions and references for water quality management in other arid and semi-arid river basins worldwide.

Keywords: Anthropogenic pollution; Driving factors; Human activity; Spatiotemporal variation; Water quality; Yellow River basin.

MeSH terms

China
Environmental Monitoring / methods
Human Activities
Humans
Nitrogen / analysis
Rivers*
Water Pollutants, Chemical* / analysis
Water Quality

Substances

Water Pollutants, Chemical
Nitrogen