Yellow River Flood Research Articles

Study on mechanical properties of unsaturated silt in the Yellow River flood area

The alluvial deposits of the Yellow River led to the formation of less clay content, loose soil particles, and low compactness of the unsaturated silt, which makes it complicated to determine the mechanical properties of the Yellow River flood area soil. To investigate the mechanical characteristics of unsaturated silt, the relationship between unsaturated silt saturation and matric suction is analyzed through the soil-water characteristic test, and the soil-water characteristic curve is fitted by the Van-Genuchten model. A series of consolidated undrained shear tests were conducted on silt in Kaifeng using the GDS triaxial apparatus, the influence of moisture content, matric suction (u a-u w), and net confining pressure (σ 3-u a) on the strength characteristics of unsaturated silt was discussed. The results indicated that the net confining pressure, moisture content, and matric suction significantly influenced the shear characteristics of unsaturated silt. The shear strength of unsaturated silt increased with increasing net confining pressure at the same moisture content. The strain-hardening state of silt at high confining pressure was more obvious, while the silt at low confining pressure showed a weak strain-hardening state. Under a constant net confining pressure, the deviatoric stress versus deviatoric strain curves of silt with low moisture content exhibited a strain-softening state, while other moisture content showed a weak strain-hardening state. At the same matric suction, the shear strength increased with increasing normal stress. The cohesion increased and then decreased while the internal friction angle decreased and then increased with the increasing moisture content and matric suction.

An experimental and theoretical study on the creep behavior of silt soil in the Yellow River flood area of Zhengzhou City

We took the silt soil in the Yellow River flood area of Zhengzhou City as the research object and carried out triaxial shear and triaxial creep tests on silt soil with different moisture contents (8%, 10%, 12%, 14%) to analyze the effect of moisture content on silt soil. In addition, the influence of moisture contents on soil creep characteristics and long-term strength was analyzed. Based on the fractional derivative theory, we established a fractional derivative model that can effectively describe the creep characteristics of silt soil in all stages, and used the Levenberg–Marquardt algorithm to inversely identify the relevant parameters of the fractional derivative creep model. The results show that the shear strengths of silt soil samples with moisture contents of 8%, 10%, 12% and 14% are 294 kPa, 236 kPa, 179 kPa and 161 kPa, respectively. The shear strength of silt soil decreases with increasing moisture content. When the moisture content increases, the cohesion of the silt soil decreases. Under the same deviatoric stress, the higher the moisture content of the silt soil, the greater the deformation will be. The long-term strength of silt soil decreases exponentially with the increase of moisture content. If the moisture content is 12%, the long-term strength loss rate of silt soil is the smallest, with a value of 32.96%. The calculated values of our creep model based on fractional derivatives have a high goodness of fit with the experimental results. This indicates that our model can better simulate the creep characteristics of silt soil. This study can provide a theoretical basis for engineering construction and geological disaster prevention in silt soil areas in the Yellow River flood area.

DOES HISTORICAL NATURAL DISASTER AFFECT CORPORATE RISK-TAKING NOWADAYS? — EVIDENCE FROM YELLOW RIVER FLOODING IN CHINA

Frequent natural disasters have had an important impact on social development and human behavior. Based on quasi-natural experiments in the flooding area of Yellow River, this study investigates the impact of the historical Yellow River flooding on the risk-taking of modern enterprises by using Regression Discontinuity design. Our study finds that those enterprises located in the flooding area of Yellow River have significantly lower risk-taking capability than those not located in the flooding area of Yellow River. Our claim remains unchanged when we use a series of robustness checks and rule out some competing explanations. This negative influence can be attributed to three mechanisms, namely trust, religious belief and uncertainty avoidance. And the negative effects are subject to heterogeneity stemming from variations in an enterprise’s ownership structure and scale. More importantly, the negative impact of the Yellow River flooding on the risk-taking of enterprises can be alleviated in areas with a higher level of formal institution.

Adversity breeds ingenuity: exploring the enduring effect of historical Yellow River flooding on family firm innovation

ABSTRACT Historical natural disasters could leave deep imprint on family firms’ innovation trajectory. Drawing upon the well-established link between geographic characteristics, institutions and innovation dynamics, this study investigates the effect of historical natural disasters on family firm innovation, focusing specifically on the impact of the historical Yellow River flooding. By leveraging the both sides of the Yellow River floodplain areas (YRFA) and employing the regression discontinuity design (RDD), we find compelling evidence that the historical Yellow River flooding significantly promotes family firm innovation in the affected areas. Meanwhile, the mechanism shows that the Yellow River flooding increases family firms’ risk-taking propensity and fosters the concentration of ownership, thereby leading to a higher engagement in innovative activities. Furthermore, we demonstrate that the positive impact of the YRFA on family firm innovation is mainly attributed to the cumulative effects of the historical flood, rather than individual flood events. Overall, this study underscores the enduring historical legacy that shape the dynamics of family firm innovation.

Study on the influence of water supply and drainage pipeline damage on urban silt ground collapse

Underground drainage pipelines play crucial roles in urban construction and development. Over time, these pipelines may incur damage and leakage due to aging and changes in surrounding loads. Ruptures and leaks in pipelines can lead to water seepage through cracks, resulting in erosion of surrounding soil layers and the formation of underground cavities. The loss of support in the soil above these cavities can lead to structural instability and eventual ground collapse. Such collapses can disrupt urban transportation systems, leading to significant social and economic consequences. This study specifically investigates ground collapse phenomena resulting from damage to drainage pipelines in silty soil within the Yellow River flood area in Zhengzhou City. By considering the influence of seepage velocity at the damaged pipeline section, the study differentiates between seepage erosion and scour erosion, conducting theoretical analyses and calculations for each scenario. The results show that ① when the surrounding area of the pipeline is damaged and the slow seepage rate causes a change in the critical groundwater level ΔH ≥ (Lσt )/((1 – n)γw), the soil around the pipeline will be damaged by seep erosion; ② when the water flow velocity at the damaged area of the pipeline is reached V 0 = 2λ(γs – γw )a 2 B 2/(9μ(B 2 – b 2)), the water flow impacts the soil and causes erosion damage. The critical pressure within the pipeline can be derived from the stress state where the pipeline is damaged P1=ρ2[2λ(γs−γw)a2B2/(9μ(B2−b2))] ; ③ the underground cavity formed by water flow erosion is assumed to be an “soil arch.” The stress analysis on it obtains the critical span of the “soil arch” when the “soil arch” is damaged 2b = [2c(H + h) + Kaγ(H + h)2 tan φ – P]/(H + h/3). This study provides a theoretical basis and technical support for the management of silty ground collapse in the Yellow River flood area.

The long-term effects of natural disasters on human capital accumulation: a quasi-natural experiment based on the Yellow River floodplain area

Abstract This study exploits the correlation between Yellow River flooding and human capital accumulation using county-level data from Anhui, Hebei, Henan, Jiangsu, and Shandong provinces in China. Employing a spatial regression discontinuity approach, we compare the differences in human capital accumulation within and beyond the Yellow River floodplain areas (YRFA). Empirical results show human capital accumulation in the YRFA is at least 12.1 percent lower than outside the YRFA. Furthermore, our results demonstrate intergenerational transmission and gender differences in the negative impact of the Yellow River flooding on human capital accumulation. The baseline specifications of this study are not affected by drought and overall natural disasters. This paper documents historical human capital accumulation, clan power, and social trust, through which Yellow River flooding has a long-term impact.

Overflowing waters, diluted investments: The enduring impact of historical Yellow River floods on enterprise fixed assets investments

Unraveling the long shadow of historical natural disasters, this study explores how the Yellow River floods shape enterprise fixed asset investments in an institutional and cultural context. Leveraging the regression discontinuity approach, we uncover a significant negative impact of these floods on investments, primarily due to weakened property rights and increased reliance on religious coping mechanisms. Further analysis suggests that the enduring impact of floods on investment persists even after controlling for confounding short-term natural disasters, financial development level, and the Tangshan Earthquake. In addition, the impact of historical Yellow River flood arises from cumulative consequences, rather than individual flood outcomes. Overall, this study not only sheds light on the dynamics between historical natural disasters and enterprise economic behavior, but also contributes to a deeper understanding regarding the broader, long-term economic impacts of climate change.

Study on bearing characteristics of super-long and super-large diameter pipe piles in silt foundation of alluvial plain of Yellow River

In recent years, super-long and super-large diameter pipe piles have been gradually applied to the foundation in the Yellow River flood area. However, its bearing mechanism is not clear, especially the unclear bearing characteristics of the pile under the eccentric state, which limits its application and development. In this regard, this paper uses the method of combining field test and numerical simulation to analyze the bearing characteristics of super-long and super-large diameter pipe piles under different pile lengths, different pile diameters, different diameter-thickness ratios, and different offsets. Combined with the specific deviation form of the pipe pile, the calculation formula of the vertical ultimate bearing capacity of the super-long and super-long diameter pipe pile in the Yellow River flooding area under the influence of the construction effect is modified. The results show that when the length of the pipe pile changes, the vertical bearing capacity changes the most, and the vertical ultimate bearing capacity of the pipe pile increases linearly with the increase of the length of the pipe pile. When the wall thickness of the pipe pile increases, the vertical bearing capacity increases approximately linearly, but the reduction of the pile displacement decreases exponentially. The greater the deflection of the pipe pile, the smaller the vertical ultimate bearing capacity. When the deflection of the pipe pile is greater than 0.35°, the vertical ultimate bearing capacity decreases rapidly with the increase of the deflection. On the basis of the traditional formula, considering the deviation form of the pipe pile, the reduction coefficient of the bearing capacity correction formula of the super-long and super-large diameter pipe pile is proposed, and the correction formula is compared with the field example. It is proved that the formula can accurately calculate the bearing capacity of the super-long and super-large diameter pipe pile. The research results of this paper are of great significance to the application and promotion of super-long and super-large diameter pipe piles in the Yellow River flood area and the evaluation of vertical ultimate bearing capacity. At the same time, the research results of this paper can also provide a reference for the study of bearing characteristics of super-long and super-large diameter pipe piles in other foundations.

Dynamic modulus and damping ratio characteristics of unsaturated silt in the Yellow River flood field

Dynamic modulus and damping ratio characteristics of unsaturated silt in the Yellow River flood field

Comparative Grain Size Analysis of Modern Flood Sediments Based on Graphic and Moment Methods in the Lower Yellow River (Huang He), China

Grain size analysis of flood sediments is a key method for understanding the sedimentary environments of rivers worldwide; however, there is limited knowledge of how to effectively reflect the sedimentary environment of lower Yellow River (Huang He) flood events using grain size parameters. In this study, two widely used grain size analysis methods, the graphic method (GM) and moment method (MM), were compared, and their applicability to flood sediment analysis in the lower Yellow River was evaluated. Modern flood sediments (n = 143) in the lower Yellow River featured a fine-grained texture and were classified as silty sand (4.95 ≤ Φ ≤ 5.03) characterized by an inadequate sorting ability. The grain size distribution patterns obtained using the GM and MM revealed positive and extremely positive deviations with sharp and flat peaks, respectively. A strong correlation (0.6966 ≤ R2 ≤ 0.9961) was observed between the mean grain size and the sorting coefficient obtained using the GM and MM. Thus, both methods were deemed suitable and could be used interchangeably. Our results indicate that the MM should be applied to assess skewness because it provided comprehensive information regarding flood sediments in the lower Yellow River, whereas the GM is recommended for kurtosis analysis, as it highlighted the primary sedimentary dynamics during flood events. Methods must be selected based on the sedimentary environment when analyzing grain size parameters.

Human disturbances dominated the unprecedentedly high frequency of Yellow River flood over the last millennium.

A warming climate may increase flood hazard through boosting the global hydrological cycle. However, human impact through modifications to the river and its catchment is not well quantified. Here, we show a 12,000-year-long record of Yellow River flood events by synthesizing sedimentary and documentary data of levee overtops and breaches. Our result reveals that flood events in the Yellow River basin became almost an order of magnitude more frequent during the last millennium than the middle Holocene and 81±6% of the increased flood frequency can be ascribed to anthropogenic disturbances. Our findings not only shed light on the long-term dynamics of flood hazards in this world's most sediment-laden river but also inform policy of sustainable management of large rivers under anthropogenic stress elsewhere.

Function and crisis of the Nationalist Yellow River flood control system in wartime China

ABSTRACT The water management of the Yellow River was subsumed under the wartime system of the Nationalist government since the beginning of China’s national resistance against Japanese aggression in 1937. The Yellow River Conservancy Commission, responsible for disaster prevention and economic exploration of the river, was on the one hand affiliated to the Ministry of Economic Affairs under the aegis of the Executive Yuan, while on another hand it was under the supervision of the First War Zone Command. The three parties above were closely related in all practical work and formed a complex operation mode which caused the water management in the flooded area to be riddled with difficulties and omissions. To be specific, albeit nominally unified, it functioned separately in its military, financial, and personnel management branches, and there was a lack of clarity in the responsibility of its three components. This resulted in chaotic circumstances, all parties impeding each other and denying responsibility. This situation reflected the serious deficiencies of the wartime system of the Nationalist government in various regards, such as in its functions, values, and administrative capacities.

Sedimentary records of palaeofloods during the late Holocene along the lower Yellow River, China: A comprehensive study based on multi-proxy

In this paper we propose a new super-comprehensive proxy that integrates the sedimentary rhythm indicators of grain size, black carbon, anthropogenic elements, and pollen for the division of alluvial sedimentary rhythms suitable for use on sediments that have or have not been disturbed by past human activity. The new proxy was applied in the analysis of sedimentary records from two boreholes (identified as JM and SZ) in the Kaifeng area of the lower Yellow River, an area that has received less research attention in terms of flood events and sedimentary records compared to its middle and upper reaches. From this analysis, flood events that occurred in the lower Yellow River since the late Holocene were reconstructed. The results suggest there are 15 and 14 sedimentary rhythms in the cores of JM and SZ, respectively. Based on historical documents, archaeological excavation data from the vicinity of the core sites, and AMS14C dating, we established the chronological framework of sedimentary rhythms in both JM and SZ cores. Using this information, we then reconstructed six Yellow River flood events impacting Kaifeng that occurred after the Warring States period in the years 225 BCE, 1387 CE, 1399 CE, 1461 CE, 1642 CE and 1841 CE. Among the six flood events, except for the flood of 225 BCE which was directly caused by human factors, the rest were caused by natural factors, mainly from prevailing climatic conditions but superimposed by human activities. The research results, therefore, can provide a scientific basis for flood prediction, prevention and risk assessment in the Yellow River Basin under the background of global change, and also provide support for clarifying the relationship between regional climate background and human activities in abnormal flood events.

Human deforestation outweighed climate as factors affecting Yellow River floods and erosion on the Chinese Loess Plateau since the 10th century

Increasing proportions of the global population are exposed to floods, including many living in the Yellow River floodplain. Since records were first kept in 602 BCE, there have been ∼1500 floods on the Yellow River, resulting in the death of millions of people. Counteracting increased flood risk requires an understanding of the relationship between climate, forest cover, erosion, and river flow. However, to assess whether the Yellow River basin is currently experiencing a period of high flood risk requires a long-term perspective. Here we use a variety of paleoenvironmental proxies (pollen, magnetic susceptibility, cladoceran assemblages) preserved in high-resolution, well-dated sediment records retrieved from an alpine lake in the middle Yellow River basin (Chinese Loess Plateau) within the agro-pastoral ecozone to examine how climatic and land-use changes affected aquatic ecosystems over the past ∼2000 years. Further, to examine changes in erosion, runoff production and flood frequency, we synthesize previously published proxy reconstructions of vegetation density, soil erosion, and dry-wet changes, as well as flood records from historical documents. We demonstrate that, following the period around the 10th century, excessive cultural deforestation outweighed climate effects and became the dominant factor that led to an unprecedented flood-rich period when drought conditions were common, cultivation expanded to meet food shortages, heavy silting raised the riverbed, and runoff and flood risk increased. These watershed changes, including enhanced soil erosion, affected the biological communities of aquatic ecosystems that led to the disappearance of planktonic cladocerans that hitherto dominated the assemblages. Increasing temperatures and weakening monsoon precipitation during the past ∼50 years, together with decreased erosion indicated by unprecedented reductions in Yellow River runoff and sediment load resulting from reforestation and damming, led to the re-establishment of planktonic cladocerans. Despite these recent changes, vegetation cover has not recovered to pre-deforestation levels, suggesting that the Yellow River is currently experiencing a high flood risk period. Our results emphasize the importance of considering vegetation–flooding relationships to help improve risk assessments and management protocols for the Yellow River.

Use of COVID-19 personal protective equipment pollutants to improve physical properties of silty sand in Yellow River flooded area

Silty sand in the Yellow River flood area (YRFA) of China exhibits a low cohesive force and water-holding capacity. Its direct use for subgrade filling leads to phenomena such as subgrade bed depression, slurry, and mud. Therefore, from the perspective of waste utilization, this study investigates disposable protective clothing (DPC) and disposable nitrile gloves (DNG) produced due to COVID-19 in combination with silty sand as subgrade filling for the YRFA. Through an unconfined compressive strength and permeability test, we studied the influence of personal protective equipment (PPE) with different moisture content, concentration, and size on the strength and permeability of mixed samples. Further, we discuss its impact on the improvement of subgrade filling in YRFA. Results show that adding DPC improves both the compressive strength and ductility of the sample. However, the impermeability of the sample remains unchanged. In contrast, the addition of DNG does not increase the compressive strength and ductility of the sample at the same time, whereas it significantly improves its impermeability. The size of PPE has a considerable influence on the compressive strength of the mixed sample, whereas it does not affect the sample permeability. This method makes use of the PPE waste produced due to COVID-19, reduces environmental pollution, and provides a novel concept for improving silty sand in the YRFA.

3D modeling of the impact of ancient Yellow River floods on urban landscapes: A new look at the late imperial landscape at the Shuntianmen Site of Kaifeng City, Henan Province, China

AbstractFloods had a massive impact on the development of ancient cities around the world and understanding this phenomenon constitutes an essential part of the history of long‐term and dynamic human–environment interactions. There remains, however, an enormous challenge in identifying records of ancient floods in urban environments due to various sedimentation and postdepositional processes that often remove, erase, and alter such environmental records. During archaeological excavations in the famous historic city of Kaifeng, we identified records of two historical floods at the Shuntianmen site. Related stratums were carefully studied, from which dating and sediment samples were collected. These excavated stratums were also scanned to obtain digital data for modeling. Combining these data, we then applied three‐dimensional modeling to reconstruct the evolution of the natural and cultural landscape of the site since the Northern Song Dynasty (960–1127 AD), which was not possible in previous studies due to the deep burial of archaeological strata. Our results indicate that the two floods occurred during the late Ming Dynasty (1368–1644 AD) and the Qing Dynasty (1636–1912 AD), respectively. During the Northern Song Dynasty, Shuntianmen was an important part of Kaifeng, which was, at that time, the capital of China and one of the largest cities in the world. Later, during the Yuan and Ming dynasties, Shuntianmen became a suburban settlement situated along various traffic routes. During the Qing Dynasty, the area became a small village. Subsequently, the area was completely abandoned and deserted until modern Kaifeng, which was built at the same place. The evolution of the regional landscape is the direct result of the interaction between the natural environment and human activities, among which the precarious alluvial processes of the Yellow River were playing an increasingly vital role. Over the centuries, the Yellow River floods, warfare, and wind‐blown sand accumulation reduced the Kaifeng region from a prosperous capital to a comparatively deserted area.

Soil-resistant organic carbon improves soil erosion resistance under agroforestry in the Yellow River Flood Plain, of China

Soil-resistant organic carbon improves soil erosion resistance under agroforestry in the Yellow River Flood Plain, of China

Enzyme-induced carbonate precipitation (EICP) combined with lignin to solidify silt in the Yellow River flood area

A novel method that combines enzyme-induced carbonate precipitation (EICP) and lignin was proposed to improve the mechanical properties of silt in the Yellow River flood area. The silt in this area is characterized by poor particle gradation, weak cohesion and low strength. It is essential to focus on the modification of silt by environmentally friendly methods. The work described in this paper investigated the unconfined compressive strength (UCS), elastic modulus, cohesion, internal friction angle and microstructure of EICP-lignin treated silt. A series of laboratory experiments was conducted, including the unconfined compressive strength (UCS) test and consolidated undrained (CU) triaxial test. The results proved that the EICP-lignin treatment enhanced silt obtained from the Yellow River flood area. All the strength parameters increased and then decreased with increasing lignin content, and their values were optimum for approximately 5% lignin. Specifically, the optimum UCS strength, cohesion and internal friction angle improved to approximately 5, 10, and 3 times those of untreated silt. In addition, the strength parameters gradually increased with curing time. Microstructure analyses were used to illustrate the physical basis for the improvement in strength with increasing aggregation of lignin and calcite.

How does turions production of Potamogeton crispus L. respond to parental population biomass and living environment

Turions production is the dominant means of propagation in Potamogeton crispus L. To understand how parental population and their living environmental factors influence the turions production of P. crispus L., a field research was conducted in Nansi Lake in Yellow River Flood Plain and southwestern Shandong Province, China. This study showed that P. crispus biomass and asexual turions showed an almost uniform spatial distribution pattern. Water depth, attenuation coefficient of light, sediment water content, sediment organic matter content, and pH were significantly related to P. crispus biomass, turions weight, and turions number. Single turion weight was determined only by P. crispus biomass, while turions number was simultaneously determined by P. crispus biomass and sediment water content. Turions weight mainly depended on turions number rather than single turion weight, and maternal biomass and sediment water content determined turions weight by affected turions number rather than single turion weight.

Natural calamity and cultural formation: A study on Yellow River flooding region

Traditional culture is usually regarded as the response to environmental change. In this paper, we tried to investigate the impact of natural calamity on the cultural formation by a case study of Yellow River flooding region (YRFR). Using national population censuses and Chinese General Social Survey data and the regression discontinuity design, we estimated the influence of YRFR on the formation of cultures, including gender norms, religious beliefs, and trust. The results suggested that inner YRFR residents preferred boys than girls, believed in religions but repelled foreign religions, and lacked the trust in others in spite of their more trust on governmental organizations. Finally, we conducted robustness checks and discussed the possible influencing paths.