In situ reconstruction of long-term extreme flooding magnitudes and frequencies based on geological archives.

Extreme flooding magnitudes and frequencies are essentially related to assessment of risk and reliability in hydrological design. Extreme flooding and its discharge are highly sensitive to regional climate change. Presently, its discharge can be reconstructed by a geological archive or record along the river valley. Two units of typical extreme flooding deposits (EFDs) carrying long-term information preserved in the Holocene loess-palaeosol sequence were found at Xipocun (XPC), which is located in Chengcheng County, China. It is situated in the downstream section of the Beiluohe (hereafter BLH) River. Based on multiple sedimentary proxy indices (grain-size distribution (GSD), magnetic susceptibility (MS), and loss-on-ignition (LOI), etc.), EFDs were interpreted as well-sorted clayey silt in suspension. They were then deposited as a result of riverbank flooding in a stagnant environment during high water level. Through the Optically Stimulated Luminescence (OSL) dating technique and stratigraphic correlations, chronologies of two identified extreme flooding periods were 7600-7400 a B.P. and 3200-3000 a B.P. Two phases of extreme flooding occurrence under climate abnormality scenarios were characterized as having high frequencies of hydrological extremes in river systems. According to simulation and verification using the Slope-Area Method and Hydrologic Engineering Center's River Analysis System (HEC-RAS) model, the extreme flooding discharges at the XPC site were reconstructed between 9625 m3/s and 16,635 m3/s. A new long-term flooding frequency and peak discharge curve, involved gauged flooding, historical flooding at Zhuangtou station and in situ reconstructed extreme flooding events, was established for the downstream BLH River. The results improve the accuracy of low-frequency flooding risk assessment and provide evidence for predicting the response of fluvial systems to climate instability. Thus, this improves the analysis of the BLH River watershed.

[1]  Ge Yu,et al.  Sedimentary records of large Holocene floods from the middle reaches of the Yellow River, China , 2000 .

[2]  Yuzhu Zhang,et al.  Investigating extreme flood response to Holocene palaeoclimate in the Chinese monsoonal zone: A palaeoflood case study from the Hanjiang River , 2015 .

[3]  J. Pang,et al.  Reconstruction palaeoflood hydrology using slackwater flow depth method in the Yanhe River valley, middle Yellow River basin, China , 2017 .

[4]  Yu Li,et al.  Projected Flood Risks in China Based on CMIP5 , 2014 .

[5]  V. Baker.  Paleoflood hydrology and extraordinary flood events , 1987 .

[6]  Zhaodong Feng,et al.  Holocene climate variations in the Altai Mountains and the surrounding areas: A synthesis of pollen records , 2018, Earth-Science Reviews.

[7]  C Rodriguez-Morata,et al.  Regional reconstruction of flash flood history in the Guadarrama range (Central System, Spain). , 2016, The Science of the total environment.

[8]  Shixia Zhang,et al.  Correlation between flood frequency and geomorphologic complexity of rivers network - A case study of Hangzhou China , 2015 .

[9]  Martin Beniston,et al.  Impacts of climatic change on water and natural hazards in the Alps: Can current water governance cope with future challenges? Examples from the European “ACQWA” project , 2011 .

[10]  C Huggel,et al.  Climate change impacts on mass movements--case studies from the European Alps. , 2014, The Science of the total environment.

[11]  R. Webb,et al.  The Scientific and Societal Value of Paleoflood Hydrology , 2013 .

[12]  Victor R. Baker,et al.  Paleoflood hydrology: Origin, progress, prospects , 2008 .

[13]  Ashish Sharma,et al.  Impact of climate change on floods in the Brahmaputra basin using CMIP5 decadal predictions , 2015 .

[14]  J. Pang,et al.  Extraordinary hydro-climatic events during the period AD 200−300 recorded by slackwater deposits in the upper Hanjiang River valley, China , 2013 .

[15]  M. Grossman,et al.  Large floods and climatic change during the Holocene on the Ara River, Central Japan , 2001 .

[16]  Y. Saito,et al.  Depositional facies and radiocarbon ages of a drill core from the Mekong River lowland near Phnom Penh, Cambodia: Evidence for tidal sedimentation at the time of Holocene maximum flooding , 2007 .

[17]  Patrick Willems,et al.  Implications of climate change on hydrological extremes in the Blue Nile basin: A review , 2015 .

[18]  Vasilis Pagonis,et al.  Reliability of single aliquot regenerative protocol (SAR) for dose estimation in quartz at different burial temperatures: A simulation study , 2016 .

[19]  G. Benito,et al.  The Holocene fluvial chronology of Spain: evidence from a newly compiled radiocarbon database , 2006 .

[20]  Yuzhu Zhang,et al.  Late Pleistocene and Holocene palaeoflood events recorded by slackwater deposits in the upper Hanjiang River valley, China , 2015 .

[21]  A. Murray,et al.  Luminescence dating of quartz using an improved single aliquot regenerative-dose protocol , 2000 .

[22]  Toshio Nakamura,et al.  Holocene East Asian monsoonal precipitation pattern revealed by grain-size distribution of core sediments of Daihai Lake in Inner Mongolia of north-central China , 2005 .

[23]  A. Singhvi,et al.  Sedimentary records and luminescence chronology of Late Holocene palaeofloods in the Luni River, Thar Desert, northwest India , 2000 .

[24]  G. Benito,et al.  The Palaeoflood record of the Gardon River, France: A comparison with the extreme 2002 flood event , 2008 .

[25]  Sumit Ghosh,et al.  Depositional mechanisms as revealed from grain-size measures of the palaeoproterozoic kolhan siliciclastics, Keonjhar District, Orissa, India , 1994 .

[26]  M. Prieto,et al.  Determination of droughts and high floods of the Bermejo River (Argentina) based on documentary evidence (17th to 20th century) , 2015 .

[27]  V. Singh,et al.  Flood-induced agricultural loss across China and impacts from climate indices , 2016 .

[28]  M. Borga,et al.  Basin-scale analysis of the geomorphic effectiveness of flash floods: A study in the northern Apennines (Italy). , 2018, The Science of the total environment.

[29]  A. Matter,et al.  Strong coherence between solar variability and the monsoon in Oman between 9 and 6 kyr ago , 2001, Nature.

[30]  Yuzhu Zhang,et al.  Holocene palaeoflood events recorded by slackwater deposits along the middle Beiluohe River valley, middle Yellow River basin, China , 2015 .

[31]  T. Ricketts,et al.  Simulating stream response to floodplain connectivity and revegetation from reach to watershed scales: Implications for stream management. , 2018, The Science of the total environment.

[32]  V. Nguyen,et al.  An at-site flood estimation method in the context of nonstationarity II. Statistical analysis of floods in Quebec , 2016 .

[33]  Nigel G. Wright,et al.  Quantifying the combined effects of multiple extreme floods on river channel geometry and on flood hazards , 2016 .

[34]  W. Toonen,et al.  Flood frequency analysis and discussion of non-stationarity of the Lower Rhine flooding regime (AD 1350-2011): Using discharge data, water level measurements, and historical records , 2015 .

[35]  A. Casas,et al.  A long-term flood discharge record derived from slackwater flood deposits of the Llobregat River, NE Spain , 2005 .

[36]  Yaofeng Jia,et al.  Extraordinary floods related to the climatic event at 4200 a BP on the Qishuihe River, middle reaches of the Yellow River, China , 2011 .

[37]  B. Horton,et al.  Nile Delta vegetation response to Holocene climate variability , 2012 .

[38]  Yuzhu Zhang,et al.  Holocene palaeoflood events recorded by slackwater deposits along the lower Jinghe River valley, middle Yellow River basin, China , 2012 .

[39]  B. Jiang,et al.  Quantitative analysis of burden of bacillary dysentery associated with floods in Hunan, China. , 2016, The Science of the total environment.

[40]  G. Benito,et al.  Hydrological response of a dryland ephemeral river to southern African climatic variability during the last millennium , 2011, Quaternary Research.

[41]  G. Benito,et al.  Holocene flooding and climate change in the Mediterranean , 2015 .

[42]  Y. Tachikawa,et al.  Impact assessment of upstream flooding on extreme flood frequency analysis by incorporating a flood-inundation model for flood risk assessment , 2017 .

[43]  M. Tamer Ayvaz.  A linked simulation–optimization model for simultaneously estimating the Manning’s surface roughness values and their parameter structures in shallow water flows , 2013 .

[44]  F. García-García,et al.  Unsteady two-dimensional paleohydraulic reconstruction of extreme floods over the last 4000 yr in Segura River, southeast Spain , 2013 .

[45]  Q. Ge,et al.  Comment on “Outburst flood at 1920 BCE supports historicity of China’s Great Flood and the Xia dynasty” , 2017, Science.

[46]  Shengli Li,et al.  Holocene environmental change inferred from the loess–palaeosol sequences adjacent to the floodplain of the Yellow River, China , 2009 .

[47]  J. López‐Sáez,et al.  Mid-late Holocene climate, demography, and cultural dynamics in Iberia: A multi-proxy approach , 2016 .

[48]  V. Baker.  Palaeoflood hydrology in a global context , 2006 .

[49]  Buda Su,et al.  Spatio-temporal changes of exposure and vulnerability to floods in China , 2014 .

[50]  Mariano Barriendos,et al.  The impact of late Holocene climatic variability and land use change on the flood hydrology of the Guadalentín River, southeast Spain. , 2010 .

[51]  J. Pang,et al.  Extraordinary Floods of 4100−4000 a BP recorded at the Late Neolithic Ruins in the Jinghe River Gorges, Middle Reach of the Yellow River, China , 2010 .

[52]  H. Meurs,et al.  Reconstructing peak discharges for historic flood levels in the city of Cologne, Germany , 2010 .