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Effect of riverbed sediment flushing and clogging on river-water infiltration rate: a case study in the Second Songhua River, Northeast China

Effet de la chasse et du colmatage des sédiments du lit d’une rivière sur le taux d’infiltration de l’eau: une étude de cas dans la deuxième rivière Songhua, au Nord-Est de la Chine

Efecto del lavado y la depositación de sedimentos en la tasa de infiltración en el cauce de un río: un estudio de caso en el Second Songhua River, noreste de China

河床沉积物的冲淤对河水入渗速率的影响-以中国东北第二松花江为例

Efeito da descarga e do depósito no leito do rio e na taxa de infiltração da água do rio: um estudo de caso no Segundo Rio Songhua, nordeste da China

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Abstract

Infiltration from natural rivers or streams is the most important source of aquifer recharge at riverbank filtration (RBF) sites. Due to the influence of river hydrological processes and changes in suspended solids in rivers, riverbed sediments often undergo significant flushing and clogging processes, which lead to obvious spatial and temporal changes in riverbed sediment permeability. Moreover, the lithology, structure, and thickness of natural riverbed sediments change with time, influencing the bank infiltration rate into groundwater. At present, how riverbed-sediment flushing and clogging influences the sediment hydraulic conductivity is not fully understood, which results in high uncertainty about the amount of water involved in RBF. An RBF site in the middle reach of the Second Songhua River, northeastern China, was studied, and continuous time series data of riverbed-sediment hydraulic conductivity were obtained for the first time. By identifying the hydrological conditions, using field monitoring, laboratory experiments and field tests, the mechanisms of change associated with sediment lithology, infiltration rate, and hydraulic conductivity during flushing and clogging processes were revealed.

Résumé

L’infiltration à partir des rivières ou cours d’eau naturels est la source la plus importante de recharge des aquifères sur les sites de filtration par berges (RBF). En raison de l’influence des processus hydrologiques des rivières et des changements des matières solides en suspension dans les rivières, les sédiments du lit des rivières subissent souvent d’importants processus de chasse et de colmatage, qui entraînent des changements spatiaux et temporels évidents de la perméabilité des sédiments du lit des rivières. En outre, la lithologie, la structure, et l’épaisseur des sédiments naturels du lit des rivières changent au cours du temps, ce qui influence le taux d’infiltration des berges dans les eaux souterraines. À l’heure actuelle, on ne comprend pas encore parfaitement comment la chasse et le colmatage des sédiments du lit des rivières influencent la conductivité hydraulique des sédiments, ce qui entraîne une grande incertitude quant à la quantité d’eau impliquée dans la RBF. Un site de RBF situé dans le cours moyen de la deuxième rivière Songhua, au nord-est de la Chine, a été étudié et des séries temporelles continues de données sur la conductivité hydraulique du lit de la rivière et des sédiments ont été obtenues pour la première fois. En identifiant les conditions hydrologiques, en utilisant des suivis de terrain, des expériences en laboratoire et des tests sur le terrain, les mécanismes de changement associés à la lithologie des sédiments, le taux d’infiltration et la conductivité hydraulique pendant les processus de chasse et de colmatage ont été révélés.

Resumen

La infiltración procedente de ríos o arroyos naturales es la fuente más importante de recarga de acuíferos en en las riberas de los ríos (RBF). Debido a la influencia de los procesos hidrológicos fluviales y a los cambios en los sólidos suspendidos, los sedimentos del cauce de los ríos suelen sufrir importantes procesos de lavado y obstrucción, que provocan cambios espaciales y temporales evidentes en la permeabilidad en los sedimentos del cauce. Además, la litología, la estructura y el espesor de los sedimentos naturales del lecho de los ríos cambian con el tiempo, lo que influye en la tasa de infiltración de las riberas. En la actualidad no se comprende del todo cómo el lavado y la obstrucción del cauce de los ríos influye en la conductividad hidráulica de los sedimentos, lo que da lugar a una gran incertidumbre acerca de la cantidad de agua que interviene en el RBF. Se estudió un sitio de RBF en el tramo medio del Second Songhua River, al noreste de China, y se obtuvieron por primera vez datos continuos de series temporales de la conductividad hidráulica del cauce del río. Mediante la identificación de las condiciones hidrológicas, utilizando monitoreo de campo, experimentos de laboratorio y pruebas de campo, se revelaron los mecanismos de cambio asociados con la litología del sedimento, la tasa de infiltración y la conductividad hidráulica durante los procesos de lavado y obstrucción.

摘要

天然河川的入渗是河岸入渗(RBF)场地含水层最重要的补给来源。由于河流水文过程以及河流中悬浮物变化的影响,河床沉积物往往存在着显著的冲淤过程,从而导致河床沉积物的渗透性发生明显的时空变化。此外,天然河床沉积物的岩性、结构和厚度等随时间的变化也会影响河水向地下水的入渗速率。目前,河床沉积物的冲淤过程对沉积物渗透系数的影响尚不完全清楚,这导致河岸入渗的水量存在高度的不确定性。以中国东北第二松花江中游的河岸入渗场地为研究区,首次获得了河床沉积物渗透系数的连续时间序列数据。通过分析水文条件,结合野外监测、实验室实验和野外测试,揭示了冲淤过程中与沉积物岩性、河水入渗速率以及渗透系数等相关参数的变化机制。

Resumo

Infiltração a partir de rios ou córregos naturais é a fonte mais importante de recarga de aquíferos em locais de filtração de margem de rio (FMR). Devido à influência dos processos hidrogeológicos do rio e às mudanças nos sólidos em suspensão nos rios, os sedimentos no leito do rio frequentemente passam por processos significativos de descarga e deposição, o que leva a claras mudanças espaciais e temporais na permeabilidade dos sedimentos do leito do rio. Ademais, litologia, estrutura e espessura dos sedimentos do leito natural mudam com o tempo, influenciando a infiltração da margem para água subterrânea. Atualmente, a forma como a descarga e a deposição dos sedimentos do leito do rio influencia a condutividade hidráulica dos sedimentos não é completamente entendida, resultando em incertezas elevadas em relação à quantidade de água envolvida na FMR. Um local de FMR no meio do Segundo Rio Songhua, nordeste da China, foi estudado, e dados contínuos de séries temporais da condutividade hidráulica dos sedimentos do leito do rio foram obtidos pela primeira vez. Ao identificar as condições hidrológicas, usando monitoramento de campo, experimentos de laboratório e testes de campo, foram revelados os mecanismos de mudança associados à litologia de sedimentos, taxa de infiltração e condutividade hidráulica durante os processos de descarga e deposição.

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Acknowledgements

The authors would like to thank the editor Jean-Christophe Comte, the associate editor Juliana G. Freitas and the anonymous reviewers for their efforts and constructive comments, which helped improve the manuscript. We would also like to thank Editage (www.editage.cn) for English language editing.

Funding

This work was funded by the National Natural Science Fund Project (Grant No. 41877178) and the Major Science and Technology Program for Water Pollution Control and Treatment (Grant No. 2014ZX07201-010). The authors would like to express deep gratitude to the funder for supporting the research described in this paper.

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Correspondence to Xiaosi Su.

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This article is part of the topical collection “Groundwater recharge and discharge in arid and semi-arid areas of China”

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Cui, G., Su, X., Liu, Y. et al. Effect of riverbed sediment flushing and clogging on river-water infiltration rate: a case study in the Second Songhua River, Northeast China. Hydrogeol J 29, 551–565 (2021). https://doi.org/10.1007/s10040-020-02218-7

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