Affiliation:
1. College of Geographic Science, Hunan Normal University Changsha China
2. State Key Laboratory of Hydrology‐Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing China
3. State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER) Institute of Tibetan Plateau Research, Chinese Academy of Sciences Beijing China
4. College of Civil Engineering and Architecture, Hunan Institute of Science and Technology Yueyang China
Abstract
AbstractPressure on river water resources may increase continuously under global climate change and the increasing intensity of human activity, and the identification of river water sources is needed to maintain water resource sustainability. In this study, river water sources were studied using hydrochemical tracers (i.e. the major ions) and end‐member mixing analysis (EMMA) during two hydrological years, in the subtropical monsoon basin of the Xiangjiang River in the south‐central China. Various water types including precipitation, river water, and mountain creek water, were collected in the basin at a high frequency. The results of EMMA showed that the average contributions from the direct input of precipitation, near‐surface runoff (represented by mountain creek water), and groundwater (represented by river water sampled during the base flow period) were 28 ± 24%, 49 ± 24% and 23 ± 16%, respectively. The contributions from these water sources to the river water varied greatly within the year, which may indicate a shift in the major flow pathways from direct precipitation input and near‐surface flow pathways in the spring rainy months (e.g. from March to May), to a deeper flow pathway in the dry or rainless months (e.g. January, February, July and December). The shift of the major flow pathways may be due to the factors such as the seasonality of precipitation, evapotranspiration and soil wetness conditions. Groundwater and near‐subsurface runoff dominated the river water and the direct input of precipitation was negligible during the dry or rainless months, and consequently, the river water chemistry was less diluted and more influenced by water‐soil/rock interactions and anthropogenic pollution during these months. The creek water contribution to the river water was relatively high in summer, especially in June and July 2021, which may indicate the substantial inter‐seasonal carryover of precipitation that contributed to the river water. With the projected increased frequency of extreme weather events such as seasonal drought, streamflow in the subtropical monsoon regions may experience greater recharge by deeper flow pathways, with the enhanced role of base flow in regulating streamflow, and there may be an increased risk to the water resource security under the condition of the decreased river dilution capacity and increased anthropogenic pollution.
Funder
National Natural Science Foundation of China
Subject
Water Science and Technology
Reference70 articles.
1. Allen R. G. Pereira L. S. Raes D. &Smith M.(1998).Crop evapotranspiration‐Guidelines for computing crop water requirements‐FAO Irrigation and drainage paper 56. FAO Rome 300(9) D05109.https://www.scscourt.org/complexcivil/105cv049053/volume3/172618e_5xagwax8.pdf
2. The Seasonal Origins of Streamwater in Switzerland
3. The implications of climate change for the water environment in England
4. Stormflow generation: A meta-analysis of field evidence from small, forested catchments
5. Water source dynamics of high Arctic river basins
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献