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Dynamic Modeling Framework of Sediment Trapped by Check-Dam Networks:A Case Study of a Typical Watershed on the Chinese Loess Plateau

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Engineering 2023年第8期27卷 209-221页

作者： Pengcheng Sun yiping wu Key Laboratory of Degraded and Unused Land Consolidation Engineering the Ministry of Natural ResourcesShaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an 710075China Key Laboratory of Soil and Water Conservation on the Loess Plateau of Ministry of Water Resources Yellow River Institute of Hydraulic ResearchZhengzhou 450003China Technology Innovation Center for Land Engineering and Human Settlement Shaanxi Provincial Land Engineering Construction Group Co.Ltd.&Xi’an Jiaotong UniversityXi’an 710115China

Check-dam construction is an effective and widely used method for sediment trapping in the Yellow River Basin and other places over the world that are prone to severe soil erosion.Quantitative estimations of the dynamic sediment trapped by check dams are necessary for evaluating the effects of check dams and planning the construction of new ones.In this study,we propose a new framework,named soil and water assessment tool(SWAT)–dynamic check dam(DCDam),for modeling the sediment trapped by check dams dynamically,by integrating the widely utilized SWAT model and a newly developed module called DCDam.We then applied this framework to a typical loess watershed,the Yan River Basin,to assess the time-varying effects of check-dam networks over the past 60 years(1957–2016).The DCDam module generated a specific check-dam network to conceptualize the complex connections at each time step(monthly).In addition,the streamflow and sediment load simulated by using the SWAT model were employed to force the sediment routing in the check-dam network.The evaluation results revealed that the SWAT-DCDam framework performed satisfactorily,with an overestimation of 11.50%,in simulating sediment trapped by check dams,when compared with a field survey of the accumulated sediment deposition.For the Yan River Basin,our results indicated that the designed structural parameters of check dams have evolved over the past 60 years,with higher dams(37.14%and 9.22%increase for large dams and medium dams,respectively)but smaller controlled areas(46.03%and 10.56%decrease for large dams and medium dams,respectively)in recent years.Sediment retained by check dams contributed to approximately 15.00%of the total sediment load reduction in the Yan River during 1970–2016.Thus,our developed framework can be a promising tool for evaluating check-dam effects,and this study can provide valuable information and support to decision-making for soil and water conservation and check-dam planning and management.

关键词： Check dams Dynamic check dam(DCDam) Loess Plateau Sediment trapping SWAT

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Flow softening and dynamic recrystallization behavior of a Mg-Gd-Y-Nd-Zr alloy under elevated temperature compressions

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Journal of Magnesium and Alloys 2023年第8期11卷 2891-2900页

作者： yiping wu Yuzhen JIA Sha Zhang Yu Liu Hanqing Xiong Gang Chen Department of Mechanical and Electrical Engineering Changsha UniversityChangsha 410003China Bichamp Cutting Technology(Hunan)Co. LtdChangsha 410200China College of Material Science and Engineering Hunan UniversityChangsha Hunan 410082China

Flow softening behavior of a homogenized Mg-7Gd-4Y-1Nd-0.5Zr alloy under compression to a final strain of∼1.8 at elevated temperatures of 450∼550℃ and a constant strain rate of 2s^(−1) has been investigated by optical microscopy,scanning electron microscopy,electron back-scattered diffraction and transmission electron microscopy.The results show that true stress first rises to the peak point and then drops to the bottom value and increases again with further increasing strain at each temperature.Twinning dynamic recrystallization(DRX)and continuous DRX contribute to the formation of new fine grains at temperatures 450∼475℃ when the restoration is caused by both DRX and texture change due to extension twinning,resulting in the larger softening degrees compared with the softening effects owing to continuous DRX and discontinuous DRX at 500∼550℃ when twinning activation is suppressed.500℃ is the transition temperature denoting a significant decline in the contribution of twinning and TDRX to the strain with increasing temperature.The cuboid-shape phase exists in both homogenized and compressed samples,while the compositions are varied.

关键词： Mg-Gd-Y alloy Elevated temperature compression Flow softening Dynamic recrystallization

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Toward Sustainable Revegetation in the Loess Plateau Using Coupled Water and Carbon Management

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Engineering 2022年第8期8卷 143-153页

作者： Fubo Zhao yiping wu Xiaowei Yin Georgii Alexandrov Linjing Qiu Department of Earth and Environmental Science School of Human Settlements and Civil EngineeringXi’an Jiaotong UniversityXi’an 710049China A.M.Obukhov Institute of Atmospheric Physics Russian Academy of SciencesMoscow 119017Russia

The"Grain-for-Green"project on the Loess Plateau is the largest revegetation program in the world.However,revegetation-induced land use changes can influence both water and carbon cycles,and the diverse consequences were not well understood.Therefore,the reasonability and sustainability of revegetation measures are in question.This study quantifies the impacts of revegetation-induced land use conversions on the water and carbon cycles in a typical watershed on the Loess Plateau and identifies suitable areas where revegetation of forest or grassland could benefit both soil and water conservation and carbon sequestration.We used a coupled hydro-biogeochemical model to simulate the changes of a few key components in terms of water and carbon by designing a variety of hypothetical land use conversion scenarios derived from revegetation policy.Compared to the baseline condition(land use in 2000),both sediment yield and water yield decreased substantially when replacing steep cropland with forest or grassland.Converting cropland with slopes larger than 25°,15°,and 6°to forest(CTF)would enhance the carbon sequestration with a negligible negative effect on soil water content,while replacing cropland with grassland(CTG)would result in a decline in net primary production but with a substantial increase in soil water content(3.8%-14.9%).Compared to the baseline,the soil organic carbon would increase by 0.9%-3.2% in CTF and keep relatively stable in CTG.Through testing a variety of hypothetical revegetation scenarios,we identified potential priority areas for CTF and CTG,where revegetation may be appropriate and potentially beneficial to conserving soil and water and enhancing carbon sequestration.Our study highlights the challenges in future water and carbon coupling management under revegetation policy,and our quantitative results and identification of potential areas for revegetation could provide information to policy makers for seeking optimal management on the Loess Plateau.

关键词： Carbon Land use change Loess Plateau Sediment SWAT-Day Cent Water resources

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Centrifugal model test on a riverine landslide in the Three Gorges Reservoir induced by rainfall and water level fluctuation

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Geoscience Frontiers 2022年第3期13卷 196-209页

作者： Fasheng Miao yiping wu Ákos Török Linwei Li Yang Xue Faculty of Engineering China University of GeosciencesWuhan 430074China Engineering Research Center of Rock-Soil Drilling&Excavation and Protection Ministry of EducationWuhan 430074China Department of Construction Materials and Engineering Geology Budapest University of Technology and EconomicsBudapestHungary College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China

Frequent soil landslide events are recorded in the Three Gorges Reservoir area,China,making it necessary to investigate the failure mode of such riverside landslides.Geotechnical centrifugal test is considered to be the most realistic laboratory model,which can reconstruct the required geo-stress.In this study,the Liangshuijing landslide in the Three Gorgers Reservoir area is selected for a scaled centrifugal model experiment,and a water pump system is employed to retain the rainfall condition.Using the techniques of digital photography and pore water pressure transducers,water level fluctuation is controlled,and multi-physical data are thus obtained,including the pore water pressure,earth pressure,surface displacement and deep displacement.The analysis results indicate that:Three stages were set in the test(waterflooding stage,rainfall stage and drainage stage).Seven transverse cracks with wide of 1–5 mm appeared during the model test,of which 3 cracks at the toe landslide were caused by reservoir water fluctuation,and the cracks at the middle and rear part were caused by rainfall.During rainfall process,the maximum displacement of landslide model reaches 3 cm.And the maximum deformation of the model exceeds 12 cm at the drainage stage.The failure process of the slope model can be divided into four stages:microcracks appearance and propagation stage,thrust-type failure stage,retrogressive failure stage,and holistic failure stage.When the thrust-type zone caused by rainfall was connected or even overlapped with the retrogressive failure zone caused by the drainage,the landslide would start,which displayed a typical composite failure pattern.The failure mode and deformation mechanism under the coupling actions of water level fluctuation and rainfall are revealed in the model test,which could appropriately guide for the analysis and evaluation of riverside landslides.

关键词： Riverine landslide The Three Gorges Reservoir Centrifugal model test Rainfall Fluctuation of water level

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System reliability analysis of reservoir landslides: Insights from long-term reservoir operation

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Journal of Earth Science 2022年

作者： Kang Liao yiping wu Fasheng Miao Faculty of Engineering， China University of Geosciences

The reservoir operation awakens numerous landslides with multiple sliding surfaces known as reservoir landslides， and the systematic stability analysis for such landslides is becoming increasingly urgent. Taking the Majiagou landslide as an example， this paper analyses the comprehensive performance of the landslide from a probabilistic point of view. Under a reservoir operation cycle， a series of numerical analyses are carried out to simulate the migration of the seepage field， then the dynamic stability of the landslide is quantified accordingly. Subsequently， the wetting-drying cycles test is used to model the weakening of strength parameters in hydro-fluctuation belt under the long-term reservoir operation. Considering the weakening effect of long-term reservoir operation on the hydro-fluctuation belt， the system reliability is evaluated using the Ditlevsen’s bounds. The results suggest that the reservoir operation can affect the stability of the landslide by changing the seepage field. The system failure probability gradually rises as the number of wetting-drying cycles increases. Compared with conventional probabilistic analysis that calculates the failure probability of each sliding surface mechanically， analyzing the landslide in terms of system reliability can effectively narrow the failure probability range， which provides an insightful idea for evaluating the systematic stability of analogous reservoir landslides.

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Probabilistic Assessment of Constitutive Model Parameters: Insight from a Statistical Damage Constitutive Model and a Simple Critical State Hypoplastic Model

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Journal of Earth Science 2023年

作者： Yang Xue Fasheng Miao yiping wu Linwei Li Daniel Dias Yang Tang Faculty of Engineering China University of Geosciences College of Resources and Environmental Engineering Key Laboratory of Karst Georesources and EnvironmentMinistry of Education Guizhou University Laboratory 3SR Grenoble Alpes University Antea Group Engineering Digital Technology Center Central-South Architectural Design Institute Co. Ltd

The constitutive model is essential for predicting the deformation and stability of rocksoil mass. The estimation of constitutive model parameters is a necessary and important task for the reliable characterization of mechanical behaviors. However, constitutive model parameters cannot be evaluated accurately with a limited amount of test data, resulting in uncertainty in the prediction of stress-strain curves. This paper proposes a Bayesian analysis framework to address this issue. It combines the Bayesian updating with the structural reliability and adaptive conditional sampling methods to assess the equation parameter of constitutive models. Based on the triaxial and ring shear tests on shear zone soils from the Huangtupo landslide, a statistical damage constitutive model and a critical state hypoplastic constitutive model were used to demonstrate the effectiveness of the proposed framework. Moreover, the parameter uncertainty effects of the damage constitutive model on landslide stability were investigated. Results show that reasonable assessments of the constitutive model parameter can be well realized. The variability of stress-strain curves is strongly related to the model prediction performance. The estimation uncertainty of constitutive model parameters should not be ignored for the landslide stability calculation. Our study provides a reference for uncertainty analysis and parameter assessment of the constitutive model.

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黄土高原典型流域淤地坝系泥沙拦截动态模拟（英文）

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Engineering 2023年第8期 209-221页

作者： Pengcheng Sun yiping wu Key Laboratory of Degraded and Unused Land Consolidation Engineering the Ministry of Natural Resources Shaanxi Provincial Land Engineering Construction Group Co.Ltd. Key Laboratory of Soil and Water Conservation on the Loess Plateau of Ministry of Water Resources Yellow River Institute of Hydraulic Research Technology Innovation Center for Land Engineering and Human Settlement Shaanxi Provincial Land Engineering Construction Group Co.Ltd.& Xi'an Jiaotong University

Check-dam construction is an effective and widely used method for sediment trapping in the Yellow River Basin and other places over the world that are prone to severe soil erosion. Quantitative estimations of the dynamic sediment trapped by check dams are necessary for evaluating the effects of check dams and planning the construction of new ones. In this study, we propose a new framework, named soil and water assessment tool(SWAT)–dynamic check dam(DCDam), for modeling the sediment trapped by check dams dynamically, by integrating the widely utilized SWAT model and a newly developed module called DCDam. We then applied this framework to a typical loess watershed, the Yan River Basin, to assess the time-varying effects of check-dam networks over the past 60 years(1957–2016). The DCDam module generated a specific check-dam network to conceptualize the complex connections at each time step(monthly). In addition, the streamflow and sediment load simulated by using the SWAT model were employed to force the sediment routing in the check-dam network. The evaluation results revealed that the SWAT-DCDam framework performed satisfactorily, with an overestimation of 11.50%,in simulating sediment trapped by check dams, when compared with a field survey of the accumulated sediment deposition. For the Yan River Basin, our results indicated that the designed structural parameters of check dams have evolved over the past 60 years, with higher dams(37.14% and 9.22% increase for large dams and medium dams, respectively) but smaller controlled areas(46.03% and 10.56% decrease for large dams and medium dams, respectively) in recent years. Sediment retained by check dams contributed to approximately 15.00% of the total sediment load reduction in the Yan River during 1970–2016. Thus, our developed framework can be a promising tool for evaluating check-dam effects,and this study can provide valuable information and support to decision-making for soil and water conservation and check-dam planning and management.

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基于多重分形的改进GRU滑坡位移预测模型

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浙江大学学报（工学版） 2024年第7期58卷 1407-1416页

作者：徐满张冬梅余想李江吴益平中国地质大学(武汉)计算机学院湖北武汉430074 湖北省自然资源厅信息中心湖北武汉430071 中国地质大学(武汉)工程学院湖北武汉430074

门控机制设计难以学习序列变化趋势,导致传统记忆网络模型对滑坡位移非平稳跃变段预测效果较差.基于多重分形改进门控循环单元(GRU),通过量化序列的变化特征来动态更新门控权重,引入循环神经网络单元的状态融合策略以学习数据的长程相... 详细信息

门控机制设计难以学习序列变化趋势,导致传统记忆网络模型对滑坡位移非平稳跃变段预测效果较差.基于多重分形改进门控循环单元(GRU),通过量化序列的变化特征来动态更新门控权重,引入循环神经网络单元的状态融合策略以学习数据的长程相关性特征.采用变分模态分解算法将滑坡累积位移分解成趋势项、周期项及随机项,利用改进GRU进行位移分量的训练和预测.选取三峡库区白水河滑坡监测点ZG93、ZG118进行仿真实验.实验结果表明,相比传统预测模型,新模型的滑坡位移形变趋势特征学习能力更强,预测精度更高.

关键词：滑坡累积位移多重分形门控循环单元(GRU) 变分模态分解循环神经网络

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Can the Grain-for-Green Program Really Ensure a Low Sediment Load on the Chinese Loess Plateau?

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Engineering 2019年第5期5卷 855-864页

作者： Pengcheng Sun yiping wu Zhifeng Yang Bellie Sivakumar Linjing Qiu Shuguang Liu Yanpeng Cai Department of Earth and Environmental Science School of Human Settlements and Civil EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China School of Civil and Environmental Engineering The University of New South WalesSydneyNSW 2052Australia Department of Land Air and Water ResourcesUniversity of CaliforniaDavisCA 95616USA Department of Civil Engineering Indian Institute of Technology BombayMumbai 400076India National Engineering Laboratory for Applied Technology of Forestry and Ecology in South China Central South University of Forestry and TechnologyChangsha 410004China

The Chinese Loess Plateau is the most seriously eroded area in the world and contributes the vast majority of the sediment that goes into the Yellow River.Since the 1950s,progressive soil and water conservation measures have been implemented—in particular,large-scale ecological restoration has been ongoing since 1999—resulting in a significant reduction of the sediment load.However,the mechanism of the sediment transport dynamics is not fully understood due to multiple and complicated influencing factors including climate change and human activities(e.g.,ecological restoration).A challenging question,then,arises:Is the current low sediment level a“new normal”in this era and in the future?To address this question,we selected a typical loess hilly region where considerable ecological restoration has been implemented,and which is regarded as the site of the first and most representative Grainfor-Green program in the Loess Plateau.We investigated the evolution of discharge–sediment relationships in the past decades(1960–2010)and their association with the soil and water conservation measures in this area.The results showed that there was a distinct change in the regression parameters of the commonly used annual discharge–sediment regression equation—a continuously increasing trend of parameter b and a decreasing trend of parameter a,accompanying the ecological restoration.The increase in exponent b(i.e.,a steeper slope)implies a potential lower sediment load resulting from low discharge and a potential higher sediment load resulting from large discharge.This finding may question the new normal of a low sediment level and implies the potential risk of a large sediment load during extremely wet years.

关键词： Discharge–sediment relationship Ecological restoration Loess hilly region Sediment load Sediment rating parameters

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Fiber-specific increase of carotenoid content promotes cotton fiber elongation by increasing abscisic acid and ethylene biosynthesis

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The Crop Journal 2023年第3期11卷 774-784页

作者： Jianyan Zeng Dan Yao Ming Luo Lingli Ding Yi Wang Xingying Yan Shu’e Ye Chuannan Wang yiping wu Jingyi Zhang Yaohua Li Lingfang Ran Yonglu Dai Yang Chen Fanlong Wang Hanyan Lai Nian Liu Nianjuan Fang Yan Pei Yuehua Xiao Biotechnology Research Center Southwest UniversityChongqing 400715China

Cotton fiber is a raw material for the global textile industry and fiber quality is essential to its industrial application.Carotenoids are plant secondary metabolites that may serve as dietary components,regulate light harvesting,and scavenge reactive oxygen species.Although carotenoids accumulate predominantly in rapidly elongating cotton fibers,their roles in cotton fiber development remain poorly understood.In this study,a fiber-specific promoter proSCFP was applied to drive the expression of GhOR1Del,a positive regulator of carotenoid accumulation,to upregulate the carotenoid level in cotton fiber in planta.Fiber length,strength,and fineness were increased in proSCFP:GhOR1Del transgenic cotton and abscisic acid(ABA)and ethylene contents were increased in elongating fibers.The ABA downstream regulator GhbZIP27a stimulated the expression of the ethylene synthase gene GhACO3 by binding to its promoter,suggesting that ABA promoted fiber elongation by increasing ethylene production.These findings suggest the involvement of carotenoids and ABA signaling in promoting cotton fiber elongation and provide a strategy for improving cotton fiber quality.

关键词： Abscisic acid Carotenoid Cotton fiber elongation Ethylene ORANGE gene

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