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Refining aquifer heterogeneity and understanding groundwater recharge sources in an intensively exploited agrarian dominated region of the Ganga Plain

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Geoscience Frontiers 2024年第4期15卷 134-147页

作者： Abhinav Patel Shive Prakash Rai Nijesh Puthiyottil Abhinesh Kumar Singh Jacob Noble Rajesh Singh Dharmappa Hagare U.D.Saravana Kumar Nachiketa Rai Kossitse Venyo Akpataku department of Geology Institute of ScienceBanaras Hindu UniversityVaranasiUttar Pradesh 221005India Isotope and Radiation Application Division Bhabha Atomic Research CentreTrombayMumbai 400085India Environmental hydrology Division National Institute of HydrologyRoorkeeUttarakhand 247667India School of Engineering Design and Built EnvironmentWestern Sydney UniversityAustralia Isotope hydrology Section Division of Physical and Chemical SciencesInternational Atomic Energy Agency(IAEA)ViennaAustria department of Earth Sciences Indian Institute of TechnologyRoorkeeUttarakhand 247667India Laboratory of Organic Chemistry and Environmental Science Department of ChemistryUniversity of KaraPO Box 404KaraTogo

Densely populated region of Ganga Plain is facing aquifer vulnerability through waterborne pollutants and groundwater stress due to indiscriminate abstraction,causing environmental and socio-economic *** address long-term groundwater resilience,it is crucial to understand aquifer heterogeneity and connectivity,groundwater recharge sources,effects of groundwater abstraction *** this con-text,present study aims to understand factors responsible for vertical and spatial variability of groundwater chemistry and to identify groundwater recharge sources in an intensively exploited agrarian region of the Ganga *** of chemometric,statistical,and isotopic analysis categorises the alluvial aquifer into zone 1(G1;ground surface to 100 m)and zone 2(G2;>100 m-210 m).The group G1 samples are characterized by a wide variation in hydrochemical species,noted with pockets of F-and NO3-rich groundwater,and fresh to more evolved water types,while group G2 groundwater is characterized by a sharp increase in freshwater types and limited variation in their isotopic and hydrochemical *** G1 groundwater chemistry is governed by soil mineralogy,local anthropogenic inputs(SO42-,Cl-,and NO3-),and manifested by multiple recharge sources(local precipitation,river,canal water,pond).The G2 group is dominated by geogenic processes and mainly recharged by the local *** signatures confirm more evolved water type for group G1 in northwestern region,while fresh-water type covers the rest of the study *** rich groundwater is attributed to sodic water under alkaline conditions and enrichedδ18O values emphasizing role of evaporation in F-mobilization from micas and amphiboles abundant in the *** findings provide insight into potential groundwater vulnerability towards inorganic contaminants,and ground water recharge *** outcome of this study will help to develop aquifer resilience towards indiscriminate groundwater extrac

关键词： Stable isotopes Hydrogeochemical attributes Groundwater recharge sources Ganga Plain

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Hydrological functioning of forested catchments,Central Himalayan Region,India

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Forest Ecosystems 2020年第4期7卷 833-850页

作者： Nuzhat Qazi Forest Research Institute DehradunUttarakhand 248006India National Institute of hydrology RoorkeeUttarakhand 247667India

Background:Central Himalayan forested catchments provide fresh water supply and innumerable ecosystem services to millions of ***,the understanding of linkages between forests and water is very crucial for availability and quality of water at catchment ***,the present study aims to understand the hydrological response of two forested catchments(namely,Arnigad and Bansigad)in the Central Himalayan ***:Threeyears’data(March,2008 to February,2011)were collected from meteorological and hydrological stations in Arnigad and Bansigad *** present paper describes the mean hydrological response of these forested catchments investigated through detailed field ***:The annual hyetograph analysis revealed that the rainfall at both the catchments was highly seasonal,and wetperiod(June–September)plays a key role in catchment *** of rainfall threshold of^200 mm(~10%of annual rainfall)significantly increased streamflow generation in both *** Arnigad,the stream was perennial with a mean baseflow of^83mm per month(~6%of annual baseflow)whereas,Bansigad had greater seasonality due to lack of streamflow during the prewetperiod(March–May).Separation of hydrographs in Arnigad and Bansigad catchments ***(6%and 31%,respectively)and baseflow(50%and 32%,respectively)helped to understand the probability of flooding during wetperiod and drought during *** forest ecosystem in Arnigad displayed healthier hydrological functioning in terms of reduced stormflow(82%),and enhanced baseflow(52%),soil moisture(13%),steady infiltration rate(22%)and lag time(~15 min)relative to *** enhanced values indicated soil capability to store water in the forested catchment(Arnigad)and helped to understand the volume of water(discharge)that was available during *** lower denudation rate at Arnigad by 41%resulted in decreased suspended sediment(18%)and bed load(75%)compared to ***

关键词： Forested catchments Stormflow Baseflow Soil moisture Sediment transport Water budget

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A Piecewise Modeling Approach for Climate Sensitivity Studies:Tests with a Shallow-Water Model

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Journal of Meteorological Research 2015年第5期29卷 735-746页

作者：邵爱梅邱崇践 NIU Guo-Yue Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou University department of hydrology and Water Resources University of Arizona Biosphere 2 University of Arizona

In model-based climate sensitivity studies, model errors may grow during continuous long-term inte- grations in both the ＂reference＂ and ＂perturbed＂ states and hence the climate sensitivity （defined as the difference between the two states）. To reduce the errors, we propose a piecewise modeling approach that splits the continuous long-term simulation into subintervals of sequential short-term simulations, and updates the modeled states through re-initialization at the end of each subinterval. In the re-initialization processes, this approach updates the reference state with analysis data and updates the perturbed states with the sum of analysis data and the difference between the perturbed and the reference states, thereby improving the credibility of the modeled climate sensitivity. We conducted a series of experiments with a shallow-water model to evaluate the advantages of the piecewise approach over the conventional continuous modeling approach. We then investigated the impacts of analysis data error and subinterval length used in the piecewise approach on the simulations of the reference and perturbed states as well as the resulting climate sensitivity. The experiments show that the piecewise approach reduces the errors produced by the conventional continuous modeling approach, more effectively when the analysis data error becomes smaller and the subinterval length is shorter. In addition, we employed a nudging assimilation technique to solve possible spin-up problems caused by re-initializations by using analysis data that contain inconsistent errors between mass and velocity. The nudging technique can effectively diminish the spin-up problem, resulting in a higher modeling skill.

关键词： climate sensitivity modeling approach nudging technique model uncertainty

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Re-study on Recurrence Period of Stokes Wave Train with High Order Spectral Method

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China Ocean Engineering 2011年第4期25卷 679-686页

作者：陶爱峰郑金海 MEE Mee Soe 陈波涛 State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Hohai University College of Harbor Coastal and Of fshore Engineering Hohai University department of Civil Engineering Myanmar Maritime UniversityMyanmar

Owing to the Benjamin-Feir instability, the Stokes wave train experiences a modulation-demodulation process, and presents a recurrence characteristics. Stiassnie and Shemer researched the unstable evolution process and provided a theoretical formulation for the recurrence period in 1985 on the basis of the nonlinear cubic Schrodinger equation （NLS）. However, NLS has limitations on the narrow band and the weak nonlinearity. The recurrence period is re-investigated in this paper by using a highly efficient High Order Spectral （HOS） method, which can be applied for the direct phase- resolved simulation of the nonlinear wave train evolution. It is found that the Stiassnie and Shemer＇s formula should be modified in the cases with most unstable initial conditions, which is important for such topics as the generation mechanisms of freak waves. A new recurrence period formula is presented and some new evolution characteristics of the Stokes wave train are also discussed in details.

关键词： Benjamin-Feir instability High Order Spectral (HOS) method recurrence period nonlinear wave-wave interaction

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Aspects of forest restoration and hydrology:linking passive restoration and soil–water recovery in Brazilian Cerrado

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Journal of Forestry Research 2021年第6期32卷 2301-2311页

作者： Luara Castilho Pereira Leonardo Balbinot Gregorio Nolazco Matus Herly Carlos Teixeira Dias Kelly Cristina Tonello hydrology of Forest Ecosystems Lab.(Hidrolef) Department of Environmental SciencesFederal University of São Carlos(UFSCar)SorocabaSao PauloBrazil department of Forest Engineering Federal University of Vicosa(UFV)VicosaMGBrazil

Although the scientific knowledge about some associations between physical parameters of the soil is consolidated,studies focused on investigating the dynamics of forest restoration processes and the structure of soils remain *** study area is located in Cerrado and is called as Private Natural Heritage Reserve(RPPN)Águas Perenes Forest(perennial water forest)and was selected as a“High Conservation Value Forest”,provides scope to investigate the soil physical properties recovery on passive restoration sites,with different ages but with the same land use ***,the aim was to investigate the soil density,moisture,penetration resistance and infiltration rate with long-term from old(FA,46 year-old),medium(FB,11 year-old)and young(FC,8 year-old)passive restoration *** was observed differences in soil density,as well as in soil moisture,resistance to penetration and infiltration *** densities recorded for FA,FB and FC were 1.38,1.48 and 1.53 g cm^(-3),*** recorded higher mean soil moisture(14.9%)than FB(11.5%)and FC(10.0%),whereas mean soil resistance to penetration was increased from FA(0.87 MPa)to FB(0.91 MPa)and FC(1.10 MPa).The average infiltration rate was almost similar in FA and FB(FA=76.43 mm h^(-1);FB=77.48 mm h^(-1))and approximately 39%higher than FC(55.79 mm h^(-1)).Thus,although soil density and moisture were different in each passive restoration site,11 year-old passive restoration site showed similar resistance to penetration and infiltration rate to the old(46 years)passive restoration *** features allowed seeing improvements in hydrological maintenance in the soil and revealed that passive restoration in Cerrado is able to improve the physical features on a soil presenting similar texture,climate and management history.

关键词： Ecological restoration Ecosystems service Forest management Forest restoration Soil conservation Tropical forest

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Study on Enhancement Effect of Cavitation Caused by HIFU Piezoelectricity Transducer

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稀有金属材料与工程 2006年第A03期35卷 527-529页

作者： Xinnan Fan Changping Zhu Shichuan He Minglei Shan Jiacai Chen department of Computer ＆ Information Engineering Hohai University Changzhou 213022 China State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China

An orthogonal ultrasonic irradiation system consisting of HIFU with frequency at 1.05 MHz combined with ultrasound with frequency at 28 kHz was applied in this *** of cavitation was detected by pH-value measurement and conductance *** result shows that the effect of cavitation caused by ultrasound with frequency at 28 kHz is greatly enhanced by HIFU piezoelectricity transducer with frequency at 1.05 MHz.

关键词： HIFU piezoelectricity transducer enhanced cavitation effect orthogonal ultrasonic irradiation

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Nash Model Parameter Uncertainty Analysis by AM-MCMC Based on BFS and Probabilistic Flood Forecasting

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Chinese Geographical Science 2011年第1期21卷 74-83页

作者： XING Zhenxiang RUI Xiaofang FU Qiang JIYi ZHU Shijiang department of Water Conservancy & Civil Engineering Northeast Agriculture University Harbin 150030 China Key Laboratory for Water-saving Agriculture of Universities in Heilongjiang Province Harbin 150030 China department of hydrology Hohai University Nanjing 210098 China

A hydrologic model consists of several parameters which are usually calibrated based on observed hy-drologic processes. Due to the uncertainty of the hydrologic processes, model parameters are also uncertain, which further leads to the uncertainty of forecast results of a hydrologic model. Working with the Bayesian Forecasting System (BFS), Markov Chain Monte Carlo simulation based Adaptive Metropolis method (AM-MCMC) was used to study parameter uncertainty of Nash model, while the probabilistic flood forecasting was made with the simu-lated samples of parameters of Nash model. The results of a case study shows that the AM-MCMC based on BFS proposed in this paper is suitable to obtain the posterior distribution of the parameters of Nash model according to the known information of the parameters. The use of Nash model and AM-MCMC based on BFS was able to make the probabilistic flood forecast as well as to find the mean and variance of flood discharge, which may be useful to estimate the risk of flood control decision.

关键词： Bayesian Forecasting System parameter uncertainty Markov Chain Monte Carlo simulation Adaptive Metropolis method probabilistic flood forecasting

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NUMERICAL STUDY OF HYDRODYNAMICS OF MULTIPLE TANDEM JETS IN CROSS FLOW

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Journal of Hydrodynamics 2011年第6期23卷 806-813页

作者： XIAO Yang TANG Hong-wu LIANG Dong-fang ZHANG Jiu-ding State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Nanjing 210098 China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China department of Engineering University of Cambridge Cambridge UK

The hydrodynamics of a single jet and four tandem jets in a cross flow are simulated by using the Computational Fluid Dynamics （CFD） software Fluent. The realizable model is used to close the Reynolds-Averaged equations. The flow characteristics of the jets, including the jet trajectory, the velocity field and the turbulent kinetic energy are obtained with various jet-to-cross flow velocity ratios in the range of 2.38-17.88. It is shown that a single jet penetrates slightly deeper than the first jet in a jet group at the same , although the difference decreases with the decrease of . It is also found that the way in which the velo-city decays along the centerline of the jet is similar for both a single jet and the first jet in a group, and the speed of the decay increases with the decrease of . The downstream jets in a group are found to behave differently due to the sheltering effect of the first jet in the group. Compared with the first jet, the downstream jets penetrate deeper into the cross flow, and the velocity decays more slowly. The circulation zone between the two upstream jets in the front is stronger than those formed between the downstream jets. The Turbulent Kinetic Energy （TKE） sees a distinct double-peak across the cross-sections close to each nozzle, with low values in the jet core and high values in the shear layers. The double-peak gradually vanishes, as the shear layers of the jet merge further away from the nozzle, where the TKE assumes peaks at the jet centerline.

关键词： multiple tandem jets jet in cross flow realizable model flow dynamics

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Nonlinear Dynamic Behaviors of A Floating Structure in Focused Waves

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China Ocean Engineering 2015年第6期29卷 807-820页

作者：曹飞凤赵西增 Institute of Harbor-Channel and Coastal Engineering Department of Civil EngineeringZhejiang University of Technology Ocean College Zhejiang University State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute

Floating structures are commonly seen in coastal and offshore engineering. They are often subjected to extreme waves and, therefore, their nonlinear dynamic behaviors are of great concern. In this paper, an in-house CFD code is developed to investigate the accurate prediction of nonlinear dynamic behaviors of a two-dimensional（2-D） box-shaped floating structure in focused waves. Computations are performed by an enhanced Constrained Interpolation Profile（CIP）-based Cartesian grid model, in which a more accurate VOF（Volume of Fluid） method, the THINC/SW scheme（THINC： tangent of hyperbola for interface capturing; SW： Slope Weighting）, is used for interface capturing. A focusing wave theory is used for the focused wave generation. The wave component of constant steepness is chosen. Comparisons between predictions and physical measurements show good agreement including body motions and free surface profiles. Although the overall agreement is good, some discrepancies are observed for impact pressure on the superstructure due to water on deck. The effect of grid resolution on the results is checked. With a fine grid, no obvious improvement is seen in the global body motions and impact pressures due to water on deck. It is concluded that highly nonlinear phenomena, such as distorted free surface, large-amplitude body motions, and violent impact flow, have been predicted successfully.

关键词： focused wave CIP method wave-structure interaction VOF method free surface flow wave breaking

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Radial tidal current field in a semi-enclosed rectangular basin: formation and evolution

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Chinese Journal of Oceanology and Limnology 2015年第4期33卷 1085-1099页

作者：钱学生陈永平张长宽潘毅 DAS Himangshu State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Hohai University College of Harbor Coastal and Offshore Engineering Hohai University department of Civil and Environmental Engineering Jackson State University

The radial tidal current field accounts for the formation of the radial sand ridges in the South Yellow Sea. Understanding the formation and evolution of this radial tidal current field is vital to assessing the morphodynamic features in the area. A semi-enclosed rectangular basin with and without a coastal barrier was schematized from the topography of the Bohai Sea and Yellow Sea. The 2D tidal current field in this basin was simulated using the DELFT3D-FLOW model. The concept of tidal wave refraction, which highlights the effect of the sloped or stepped submarine topography on the propagation of the tidal waves, was introduced to explain the formation of the radial tidal current field. Under the effect of tidal wave refraction, co-phase lines of the counterclockwise rotating tidal wave and incident tidal wave are transformed into clockwise and counterclockwise deflections, respectively, leading to the convergence and divergence of the flow field. Regardless of whether a coastal barrier exists or not, the outer radial tidal current field might emerge over certain topography. The responses of the radial tidal current field in this basin to the environmental variations such as coastline changes and bottom erosions were discussed. Results show that local protrusion near the focal point of the radial tidal current field will have limited effects on the location of the tidal system. However, a remarkable shift of the amphidromic point toward the entrance and central axis of this basin and a movement of the focal point of the radial tidal current field toward the entrance could be caused by the significant seaward coastline advance and submarine slope erosion.

关键词： semi-enclosed rectangular basin coastal barrier M2 tide amphidromic point radial tidal current field

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