Hydro-geomorphological characteristics in response to the water-sediment regulation scheme of the Xiaolangdi Dam in the lower Yellow River

Floodplains provide valuable social and ecological environment functions, and understanding the rates and patterns of floodplain sedimentation/erosion is critical for floodplain management and rehabilitation. The sediment entering the lower Yellow River has been dramatically reduced, and the geomorphology has changed greatly during the operation of the Xiaolangdi (XLD) reservoir since 2000. Utilizing sediment resources is the key to managing the downstream river, and the floodplains not only play the roles of flood mitigation, detention and de-sanding but also provide land to support local residents and economic development; however, the floodplain currently faces competition between land development and protection. This research presents a detailed investigation of changes in the sediment budget and morphology of the braided reach between Huayuankou (HYK) and Gaocun (GC) during 2000-2017 using digital elevation models (DEMs) and the historical bathymetry of the braided reach. During the implementation of the water-sediment regulation scheme (WSRS), the long-term low-concentration flow released from the XLD reservoir leads to a fully scoured long channel, further improving the bank-full discharge and reducing the risk of floods on floodplains. However, the floodplains have gradually changed from sedimentation to erosion due to the continual construction of farm dykes and control works, land use changes and other forms of land disturbance, including water and soil conservation measures and climate change. The cumulative eroded volume was approximately 11.47×108 m3 along the HYK - GC reach between 2000 and 2017, of which 3.08×108 m3 originated from the floodplains, with an average annual erosion rate of 1.3 cm/yr. To develop the economy and guide floodplain construction, we propose a new method of environmental management to reconstruct the floodplain domain into different zones for immigration resettlement areas, agricultural areas and resource development and utilization areas, with the methods of river dredging and floodplain filling.

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Multiple time scale analysis of sediment and runoff changes in the Lower Yellow River

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-379-357-2018 ◽

2018 ◽

Vol 379 ◽

pp. 357-362

Author(s):

Kaige Chi ◽

Zhao Gang ◽

Bo Pang ◽

Ziqian Huang

Keyword(s):

Time Scale ◽

Sediment Load ◽

Yellow River ◽

Mean Value ◽

Multiple Time ◽

Multiple Time Scale ◽

Lower Yellow River ◽

The Lower Yellow River ◽

Regulation Scheme ◽

Runoff Changes

Abstract. Sediment and runoff changes of seven hydrological stations along the Lower Yellow River (LYR) (Huayuankou Station, Jiahetan Station, Gaocun Station, Sunkou Station, Ai Shan Station, Qikou Station and Lijin Station) from 1980 to 2003 were alanyzed at multiple time scale. The maximum value of monthly, daily and hourly sediment load and runoff conservations were also analyzed with the annually mean value. Mann–Kendall non-parametric mathematics correlation test and Hurst coefficient method were adopted in the study. Research results indicate that (1) the runoff of seven hydrological stations was significantly reduced in the study period at different time scales. However, the trends of sediment load in these stations were not obvious. The sediment load of Huayuankou, Jiahetan and Aishan stations even slightly increased with the runoff decrease. (2) The trends of the sediment load with different time scale showed differences at Luokou and Lijin stations. Although the annually and monthly sediment load were broadly flat, the maximum hourly sediment load showed decrease trend. (3) According to the Hurst coefficients, the trend of sediment and runoff will be continue without taking measures, which proved the necessary of runoff-sediment regulation scheme.

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MODEL FOR LOSS ASSESSMENT DUE TO FLOOD IN THE LOWER YELLOW RIVER

Environmental Engineering and Management Journal ◽

10.30638/eemj.2015.207 ◽

2015 ◽

Vol 14 (8) ◽

pp. 1933-1939

Author(s):

Xianqi Zhang ◽

Weiwei Han ◽

Xiaofei Peng ◽

Cundong Xu

Keyword(s):

Yellow River ◽

Loss Assessment ◽

Lower Yellow River ◽

The Lower Yellow River

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High-Arsenic Groundwater in Paleochannels of the Lower Yellow River, China: Distribution and Genesis Mechanisms

Water ◽

10.3390/w13030338 ◽

2021 ◽

Vol 13 (3) ◽

pp. 338

Author(s):

Chuanshun Zhi ◽

Wengeng Cao ◽

Zhen Wang ◽

Zeyan Li

Keyword(s):

Yellow River ◽

The Yellow River ◽

Rock Interaction ◽

Lower Yellow River ◽

The Lower Yellow River ◽

Groundwater Samples ◽

Groundwater Systems ◽

Different Sources ◽

High Arsenic ◽

High Arsenic Groundwater

High–arsenic (As) groundwater poses a serious threat to human health. The upper and middle reaches of the Yellow River are well–known areas for the enrichment of high–arsenic groundwater. However, little is known about the distribution characteristics and formation mechanism of high-As groundwater in the lower reach of the Yellow River. There were 203 groundwater samples collected in different groundwater systems of the lower Yellow River for the exploration of its hydrogeochemical characteristics. Results showed that more than 20% of the samples have arsenic concentrations exceeding 10 μg/L. The high-As groundwater was mainly distributed in Late Pleistocene–Holocene aquifers, and the As concentrations in the paleochannels systems (C2 and C4) were significantly higher than that of the paleointerfluve system (C3) and modern Yellow River affected system (C5). The high-As groundwater is characterized by high Fe2+ and NH4+ and low Eh and NO3−, indicating that reductive dissolution of the As–bearing iron oxides is probably the main cause of As release. The arsenic concentrations strikingly showed an increasing tendency as the HCO3− proportion increases, suggesting that HCO3− competitive adsorption may facilitate As mobilization, too. In addition, a Gibbs diagram showed that the evaporation of groundwater could be another significant hydrogeochemical processes, except for the water–rock interaction in the study area. Different sources of aquifer medium and sedimentary structure may be the main reasons for the significant zonation of the As spatial distribution in the lower Yellow River.

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