Article
Soil Science
Nicolas Guillermo Polich, Luis Alberto Lozano, Rafael Villarreal, Maria Paz Salazar, Esteban M. Melani, C. German Soracco
Summary: No tillage (NT) in simplified agricultural systems has negative effects on soil physical quality, but the inclusion of winter cover crops (CC) can help preserve the physical fertility of soils under NT. This study aimed to determine the effect of cover crop incorporation under NT on the soil pore system configuration and anisotropy of unsaturated hydraulic properties. Results showed that cover crops increased the structure porosity and modified the anisotropy of unsaturated hydraulic conductivity.
SOIL & TILLAGE RESEARCH
(2023)
Article
Multidisciplinary Sciences
Leonardo Scalco, Leandro Tonietto, Raquel Quadros Velloso, Graciela Racolte, Luiz Gonzaga, Mauricio Roberto Veronez
Summary: This study proposes an alternative method to determine the roughness coefficient in rock plugs by using photogrammetry and computer vision techniques. The results show that obtaining the roughness coefficient over the entire surface of the three-dimensional model has peculiarities that would not be observed in the two-dimensional reading.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Geological
Jeevan Joseph, Shetty Rakshith, D. N. Singh, C. S. Tang
Summary: This article introduces the methods and techniques for determining the unsaturated hydraulic conductivity of various porous media in the field of geotechnical and agriculture engineering. It also points out the limitations and challenges of existing methodologies. To overcome these limitations, a novel methodology, (MI-EC)k(u), is proposed and its robustness and ease of use are demonstrated through experiments.
Article
Engineering, Civil
Ke Chen, Chen Wang, Fayun Liang
Summary: This paper presents a fractal-based hydraulic model that accurately describes the evolution of soil water characteristics and hydraulic conductivity during soil deformation.
JOURNAL OF HYDROLOGY
(2023)
Article
Engineering, Geological
Behrooz Daneshian, Ghassem Habibagahi, Ehsan Nikooee
Summary: Hydraulic conductivity of unsaturated soils is crucial for modeling various phenomena, and is influenced by factors such as soil water content and pore connectivity. Current predictive models do not adequately consider pore connectivity, while pore network models offer a more realistic portrayal of soil characteristics.
Article
Soil Science
Behzad Ghanbarian
Summary: Modeling fluid flow in dual-porosity media with bi-modal pore size distributions has practical applications to understanding transport in agricultural soils. Comparing theoretical estimations with experimental measurements shows that a modified capillary pressure curve model results in more accurate unsaturated hydraulic conductivity (KSw) estimations. Additionally, accurate characterization of the capillary pressure curve and correct determination of the crossover point separating the structure domain from the texture one are crucial for precise estimation of K(Sw) via critical path analysis (CPA).
SOIL & TILLAGE RESEARCH
(2021)
Article
Engineering, Chemical
Md Rajibul Karim, David Hughes, Md Mizanur Rahman
Summary: Changes in pore water pressure due to soil-atmospheric boundary interaction can have significant effects on soil behavior and the safety of geotechnical structures. Hydraulic conductivity is an important parameter for analyzing the behavior of soil subjected to atmospheric boundary interactions, but it is difficult to determine accurately. This paper presents a simple alternative method for estimating the hydraulic conductivity of unsaturated soils by re-analyzing observed pore water pressure response. The numerical model accurately captures the development of suction, positive pore water pressure, and changes in water content, demonstrating the usefulness of the proposed method.
Article
Chemistry, Physical
Tian Chen, Mao Du, Qiangling Yao
Summary: This study proposes a novel theoretical method for the evolution of the pore system in compacted bentonite based on its stacked microstructure. The Kozeny-Carman equation is revised to evaluate the hydraulic conductivity, taking into account the microstructure effects. A new constitutive relationship is developed to describe the unsaturated hydraulic conductivity. The results show good agreement between the predictions and experimental observations.
Article
Engineering, Geological
Suaiba Mufti, Arghya Das
Summary: This paper presents a pore-scale model for predicting unsaturated hydraulic conductivity along drying and wetting paths in unsaturated soils. The model combines the discrete element method for soil packing and pore network modeling to simulate fluid flow, incorporating pore-scale phenomena. The predicted hydraulic conductivity compares favorably to experimental data and outperforms other physically-based models.
Article
Chemistry, Multidisciplinary
Jhan Piero Rojas, Juan Carlos Ruge, Gustavo Adolfo Carrillo
Summary: This study focused on determining the hydraulic conductivity in porous media under total and partial saturation conditions, finding that the differences in granular microstructures of materials and hydraulic interaction mechanisms significantly affected the values of k(s) and k(u) and the coupling between pore domains and water regimes.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Geological
Hao Wang, Rui Chen, Anthony Kwan Leung, Junwen Huang
Summary: The soil temperature of vegetated landfill earthen covers changes over time due to the heat released by the degradation of municipal solid waste. This study conducted an experimental campaign to determine the soil water-retention curve (SWRC) and hydraulic conductivity function (HCF) of unsaturated rooted soils at different temperatures. The results showed that increasing temperature reduced water-retention capacity and enhanced soil hydraulic conductivity. A new nonisothermal SWRC model was developed to capture the dual effects of roots and temperature.
CANADIAN GEOTECHNICAL JOURNAL
(2023)
Article
Multidisciplinary Sciences
Huanhuan Qin
Summary: Centrifugal modelling has been used in the past to study groundwater flow and transport processes, but there has been disagreement on whether numerical models can effectively simulate centrifugal systems under unsaturated flow conditions. This study developed a numerical model based on Richards' equation to predict one-dimensional unsaturated flow in centrifugal systems. The model was validated using data from physical models in four benchmark problems, and its ability to close mass balance was also tested. The results showed that the numerical model was successful in recreating the benchmark problems, indicating its feasibility in simulating unsaturated flow conditions. The study also highlighted the importance of spatial grid resolution and suggested the use of adaptive temporal time stepping to improve computational efficiency. Dimensionless scaling factors were found to be useful in scaling centrifugal systems.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Civil
J. A. P. Pollacco, J. Fernandez-Galvez, Q. de Jong van Lier
Summary: We developed a novel, lognormal, pore-scale, unsaturated hydraulic conductivity model, K(psi)Model, which does not require saturated hydraulic conductivity, Ks, as an input parameter. The K(psi)Model is derived solely from hydraulic parameters describing a bimodal, lognormal, pore-scale, soil water retention curve theta(psi). Compared to previously developed models, the K(psi)Model does not require the use of integrals and can be computed from a spreadsheet and distinguishes between macropore (non-equilibrium) and matrix (equilibrium) flows. The K(psi)Model gives improved results when the hydraulic parameters are dynamically constrained and when theta(psi) describes a bimodal, lognormal distribution.
JOURNAL OF HYDROLOGY
(2023)
Article
Environmental Sciences
David P. Huber, Greg L. Butters, Luis A. Garcia
Summary: This study investigates the impact of salinity on soil hydraulic properties through experiments, finding that the effect of solution chemistry on hydraulic conductivity increases with decreasing soil moisture. Current models may overestimate drainage, recharge, or bare soil evaporation. The research demonstrates that hydraulic conductivity can decrease by up to five orders of magnitude relative to native soils at reduced soil water contents.
VADOSE ZONE JOURNAL
(2021)
Article
Engineering, Civil
Gioacchino Francesco Andriani, Nicola Pastore, Concetta Immacolata Giasi, Mario Parise
Summary: This study presents an integrated investigation of the hydraulic properties of homogeneous calcarenites with a complex pore network, focusing on water infiltration and retention mechanisms under high water inflow from dry to wet conditions. The experimental and model-based assessment of the materials' hydraulic properties under unsaturated conditions was conducted, with a particular emphasis on the dominance of macro-porosity on water flow and infiltration rate. Theoretical solutions and model predictions were compared with experimental data, highlighting the gravity-driven flow through macropores as the main mechanism for wetting front propagation.
JOURNAL OF HYDROLOGY
(2021)
Article
Geosciences, Multidisciplinary
Xuan Yu, Holly A. Michael
GEOPHYSICAL RESEARCH LETTERS
(2019)
Article
Computer Science, Interdisciplinary Applications
Xuan Yu, Daniel Moraetis, Nikolaos P. Nikolaidis, Bailing Li, Christopher Duffy, Bingjun Liu
ENVIRONMENTAL MODELLING & SOFTWARE
(2019)
Article
Water Resources
Xuan Yu, Anna Lamacova, Lele Shu, Christopher Duffy, Pavel Kram, Jakub Hruska, Tim White, Kairong Lin
HYDROLOGICAL SCIENCES JOURNAL
(2020)
Article
Water Resources
Xuan Yu, Holly A. Michael
ADVANCES IN WATER RESOURCES
(2019)
Editorial Material
Geochemistry & Geophysics
Xuan Yu, Christopher J. Russoniello, Leanne K. Morgan, Gudrun Massmann, Guizhi Wang
Article
Environmental Sciences
Julia A. Guimond, Xuan Yu, Angelia L. Seyfferth, Holly A. Michael
WATER RESOURCES RESEARCH
(2020)
Article
Geochemistry & Geophysics
Angelia L. Seyfferth, Frances Bothfeld, Rodrigo Vargas, Jason W. Stuckey, Jian Wang, Kelli Kearns, Holly A. Michael, Julia Guimond, Xuan Yu, Donald L. Sparks
GEOCHIMICA ET COSMOCHIMICA ACTA
(2020)
Article
Engineering, Civil
Jiangchao Qiu, Bingjun Liu, Xuan Yu, Zibo Yang
Summary: This study employed a shifting method to estimate nonstationary rating curves and found key indicators in calculating change point range, segment results, and discharge prediction, while also discussing how to reduce the use of calibration data.
JOURNAL OF HYDROLOGY
(2021)
Article
Water Resources
Wenjuan Zheng, Anna Lamacova, Xuan Yu, Pavel Kram, Jakub Hruska, Pavel Zahradnicek, Petr Stepanek, Ales Farda
Summary: Climate warming is profoundly affecting the hydrological cycle, with Europe experiencing heat waves and Central Europe facing consecutive years of drought. By simulating future climate scenarios, significant impacts on runoff and evapotranspiration were found, emphasizing the importance of considering subsurface processes in projecting hydrological responses to a warming climate.
HYDROLOGICAL PROCESSES
(2021)
Article
Engineering, Civil
Xuan Yu, Zexuan Xu, Daniel Moraetis, Nikolaos P. Nikolaidis, Franklin W. Schwartz, Yu Zhang, Lele Shu, Christopher J. Duffy, Bingjun Liu
Summary: Submarine groundwater discharge significantly impacts coastal waters, but its variability is often challenging to compare due to various factors. Research on Crete Island in the Mediterranean Sea showed that fresh SGD contributes substantially to water flow into the Mediterranean, influenced by river mouths and precipitation.
JOURNAL OF HYDROLOGY
(2021)
Article
Environmental Sciences
Xuan Yu, Holly A. Michael
Summary: Numerical models of variable-density groundwater flow and salt transport are crucial for predicting salinity distributions in coastal aquifers and estimating submarine groundwater discharge. The study found that the scale of representation of heterogeneity significantly impacts salinity distributions and flow paths, and simulated density distributions control both the rate and direction of subsurface saltwater circulation.
WATER RESOURCES RESEARCH
(2022)
Article
Environmental Sciences
Yuxuan Hou, Jie Yang, Christopher J. Russoniello, Tianyuan Zheng, Mei-lin Wu, Xuan Yu
Summary: Shrimp aquaculture can lead to groundwater salinization and increased submarine groundwater discharge (SGD), but research on this topic is limited. In this study, a numerical simulation approach was used to assess the impacts of shrimp farm irrigation on groundwater salinization and SGD. The results showed that pond water depth had a primary control on the mass of saltwater infiltration, while farm width had a primary control on recovery rate. Both pond water salinity and depth affected fresh and saline SGD. This study highlights the previously unrecognized mechanism of aquaculture on coastal aquifer vulnerability and SGD, emphasizing the need for further research on the impact of aquaculture on coastal groundwater resources.
WATER RESOURCES RESEARCH
(2022)
Article
Environmental Sciences
Yuxuan Hou, Gang Zhao, Xiaohong Chen, Xuan Yu
Summary: Coastal aquaculture is expanding globally as an important source of animal proteins for human consumption. However, it may cause environmental concerns. This study developed a method using shape and water quality parameters to accurately map aquaculture ponds, and the results showed high accuracy in distinguishing them from other water bodies. The method has great potential for global application in extracting long-term series and large-scale aquaculture ponds.
Article
Engineering, Environmental
Xuan Yu, Joshua J. LeMonte, Junxia Li, Jason W. Stuckey, Donald L. Sparks, John G. Cargill, Christopher J. Russoniello, Holly A. Michael
Summary: Historical industrial activities have caused soil contamination at coastlines worldwide, which are susceptible to disruptions by climate change and rising sea levels. However, the effects of hydrologic dynamics on contaminant transportation in tidal environments have not been extensively studied. This research collected data from various sensors at a contaminated site near a freshwater tidal channel and found that seasonal groundwater interactions and sub-daily water level fluctuations in the channel contribute to varying redox conditions and contaminant concentrations. The findings highlight the importance of understanding the impacts of sea-level rise on the mobility of coastal solutes.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Civil
Qiaoyu Wang, Jie Yang, Ingo Heidbuechel, Xuan Yu, Chunhui Lu
Summary: The excessive use of nitrogen fertilizer has negative effects on drinking water quality and aquatic ecosystems. This study examines the spatiotemporal variation of nitrogen retention and the impact of external nitrogen input heterogeneity on retention capacity and nitrogen export in a small catchment in Germany. The findings highlight the importance of considering land-use patterns and regional wetness conditions to manage surface water quality.
JOURNAL OF HYDROLOGY
(2023)