Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3D

The heterogeneity of layered soils affects the transport processes of water in the vadose zone. However, the mechanism of soil moisture transport in the vadose zone under heterogeneous media conditions, especially the three-dimensional transport mechanism, is a frontier problem to be studied. In ord...

Full description

Bibliographic Details
Main Authors: Simin Xie, Guizhang Zhao
Format: Article
Language:English
Published: MDPI AG 2023-10-01
Series:Water
Subjects:
Online Access:https://www.mdpi.com/2073-4441/15/20/3550
_version_ 1797572038731235328
author Simin Xie
Guizhang Zhao
author_facet Simin Xie
Guizhang Zhao
author_sort Simin Xie
collection DOAJ
description The heterogeneity of layered soils affects the transport processes of water in the vadose zone. However, the mechanism of soil moisture transport in the vadose zone under heterogeneous media conditions, especially the three-dimensional transport mechanism, is a frontier problem to be studied. In order to reveal the law of soil water transport in the vadose zone under heterogeneous media, this paper constructs a three-dimensional model of water transport using HYDRAS-3D (V 2.x) software through in situ tests of water transport in 3 × 3 × 4 m sample and verifies and analyzes the model. The vertical distribution and variability of soil water content and the temporal and spatial rules of soil water transversal transport at the soil–layer interface were analyzed. The results indicate that after adjusting the parameters in the HYDRAS-3D model using measured values, the simulation results are reasonable, and the model has high reliability. To represent the water content variability characteristics of the test tube profile, water movement in the vadose zone was classified as follows: (I) steady period (April–September, less affected by rainfall), (II) slow change period (January–March), and (III) rainfall rapid change period (June, when the impact of rainfall on the test cylinder was greater). The two largest values of the soil water potential variation gradient, 19.9 and 17.8 cm/d, were observed in the silty clay layer of the test cylinder, and the influence of evaporation and infiltration in the silty clay layer was most notable at the interface. The lateral transport of soil water at the interface was influenced to a certain degree by the layered heterogeneity, wherein the fine sand layer exhibited the most pronounced impact. This was followed by silt and silty clay layers, with the silt layer showing the lowest degree of influence. The research results can provide scientific reference for the rational planning of water resources in the Yinchuan Plain.
first_indexed 2024-03-10T20:48:59Z
format Article
id doaj.art-9243508708a5472bac8f20c131d3ba08
institution Directory Open Access Journal
issn 2073-4441
language English
last_indexed 2024-03-10T20:48:59Z
publishDate 2023-10-01
publisher MDPI AG
record_format Article
series Water
spelling doaj.art-9243508708a5472bac8f20c131d3ba082023-11-19T18:29:15ZengMDPI AGWater2073-44412023-10-011520355010.3390/w15203550Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3DSimin Xie0Guizhang Zhao1College of Geosciences and Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450046, ChinaCollege of Geosciences and Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450046, ChinaThe heterogeneity of layered soils affects the transport processes of water in the vadose zone. However, the mechanism of soil moisture transport in the vadose zone under heterogeneous media conditions, especially the three-dimensional transport mechanism, is a frontier problem to be studied. In order to reveal the law of soil water transport in the vadose zone under heterogeneous media, this paper constructs a three-dimensional model of water transport using HYDRAS-3D (V 2.x) software through in situ tests of water transport in 3 × 3 × 4 m sample and verifies and analyzes the model. The vertical distribution and variability of soil water content and the temporal and spatial rules of soil water transversal transport at the soil–layer interface were analyzed. The results indicate that after adjusting the parameters in the HYDRAS-3D model using measured values, the simulation results are reasonable, and the model has high reliability. To represent the water content variability characteristics of the test tube profile, water movement in the vadose zone was classified as follows: (I) steady period (April–September, less affected by rainfall), (II) slow change period (January–March), and (III) rainfall rapid change period (June, when the impact of rainfall on the test cylinder was greater). The two largest values of the soil water potential variation gradient, 19.9 and 17.8 cm/d, were observed in the silty clay layer of the test cylinder, and the influence of evaporation and infiltration in the silty clay layer was most notable at the interface. The lateral transport of soil water at the interface was influenced to a certain degree by the layered heterogeneity, wherein the fine sand layer exhibited the most pronounced impact. This was followed by silt and silty clay layers, with the silt layer showing the lowest degree of influence. The research results can provide scientific reference for the rational planning of water resources in the Yinchuan Plain.https://www.mdpi.com/2073-4441/15/20/3550layered heterogeneitysoil water movement in the vadose zonesoil water potentialHYDRAS-3Dnumerical simulation
spellingShingle Simin Xie
Guizhang Zhao
Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3D
Water
layered heterogeneity
soil water movement in the vadose zone
soil water potential
HYDRAS-3D
numerical simulation
title Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3D
title_full Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3D
title_fullStr Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3D
title_full_unstemmed Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3D
title_short Study on Spatiotemporal Transport Characteristics of Soil Moisture in Layered Heterogeneous Vadose Zone Based on HYDRAS-3D
title_sort study on spatiotemporal transport characteristics of soil moisture in layered heterogeneous vadose zone based on hydras 3d
topic layered heterogeneity
soil water movement in the vadose zone
soil water potential
HYDRAS-3D
numerical simulation
url https://www.mdpi.com/2073-4441/15/20/3550
work_keys_str_mv AT siminxie studyonspatiotemporaltransportcharacteristicsofsoilmoistureinlayeredheterogeneousvadosezonebasedonhydras3d
AT guizhangzhao studyonspatiotemporaltransportcharacteristicsofsoilmoistureinlayeredheterogeneousvadosezonebasedonhydras3d