HYDRUS Software Research Articles

Evaluation of Subsurface Drip Irrigation Designs in a Soil Profile with a Capillary Barrier

Enhanced water use efficiency (WUE) is the key to sustainable agriculture in arid regions. The installation of capillary barriers (CB) has been suggested as one of the potential solutions. CB effects are observed between two soil layers with distinctly different soil hydraulic properties. A CB helps retain water in the upper, relatively fine-textured soil layer, suppressing water losses by deep drainage. However, retaining water in a shallow surface layer also intensifies water loss by evaporation. The use of subsurface drip irrigation (SDI) with a CB may prevent such water loss. This study evaluated the performance of SDI in a soil profile with a CB using a pot experiment and numerical analysis with the HYDRUS (2D/3D) software package. The ring-shaped emitter was selected for the SDI system for its low capital expenditures (CapEx) and maintenance. Strawberry was selected as a model plant. The results indicated that the proposed SDI system with a CB was effective in terms of WUE. The numerical analysis revealed that the CB’s depth influences the system’s water balance more than the ring-shaped emitter’s installation depth. While the CB’s shallow installation led to more root water uptake by the strawberry and less water loss by deep drainage, it induced more water loss by evaporation.

Effect of multilayered groundwater mounds on water dynamics beneath a recharge basin: Numerical simulation and assessment of surface injection

AbstractInteractions between groundwater mounds caused by a geologic layer contrast affect the efficiency of managed aquifer recharge in arid areas. However, research has rarely examined the roles of groundwater mounding size variations on soil water dynamics in a stratified vadose zone in response to a sustained infiltration source. Numerical experiments were conducted on a two‐dimensional vertical‐section domain using HYDRUS software to simulate the behaviours of two adjacent (upper and lower) groundwater mounds underlying an infiltration basin subjected to clay loam and sandy alternately‐layered soil profiles. The model successfully predicted the volume and extent of perched water and approximated vertical travel times during events generating downward fluxes from the surface injection. The response time of the mounding width (lateral extension) to the surface injection was delayed as compared to that of the mounding height (vertical extension), especially for the lower water mound. The mounding heights and widths show a strongly positive correlation with the infiltration rates of both high‐ and low‐permeability layers where the injected water mounded, while the water storage amounts in the high‐ and low‐permeability layers were governed by the mounding height and width, respectively. Exploratory simulations were then employed to assess the dependence of groundwater mounding behaviours and recharge performances on surface injection strategies. Results suggest that, by reducing injection rate or shortening injection duration, the near‐term fraction of the surface injection converted to deep recharge is likely to be increased due to the narrowed groundwater mounding size, which would be limited by the water‐retarding effect of layer contrasts. This study has important implications for predicting and understanding multilayered groundwater mounding behaviours and associated water mass balance under the geologic stratification, and is expected to aid in optimizing the infiltration basin operation for aquifer recharge.

A Simulation of Salt Transport in NaCl-Laden Soil Barrier to Control Subterranean Termites in an Earth Embankment

Subterranean termite activity can increase the hydraulic conductivity and water infiltration of filling soil, and therefore affects the stability of an earth embankment and subsequent safety. As a physical barrier for sustainable termite management, NaCl-laden soil barrier (NLSB) is a promising alternative for subterranean termite control in earth embankments. This novel technology can prevent tunneling and penetration of subterranean termites into the interior of an embankment and has been widely employed for more than 20 years in Zhejiang Province, China. The efficacy and longevity of NLSB depend on the long-term presence of NaCl concentration in soil barriers. The aim of this study is to develop an understanding of water flow and salt transport in NLSB based on the two-dimensional Richards’ equation and convection dispersion equation using the HYDRUS software package. Conceptual and numerical models of NLSB are modeled using scenario analysis according to water level fluctuations, saturated hydraulic conductivity, and rainfall infiltration conditions. Furthermore, the center and spread variance of a solute mass over a 100-year period are quantified using moment analysis. As flood frequency, saturated hydraulic conductivity, and rainfall infiltration flux increase, salt desalination in NLSB significantly increases. When the rainfall infiltration flux is 1% of the annual average rainfall, the total amount of salt transport and leaching can increase by 55%. Moreover, these results facilitate better long-term sustainable management of existing sites and optimal design of future NLSBs.

Water Distribution from Artificial Recharge via Infiltration Basin under Constant Head Conditions

The vadose zone plays a significant role during artificial recharge via the infiltration basin. Its thickness, lithology, heterogeneity, among others greatly affect the recharge efficiency. The main objective of this research is to establish the role of the vadose zone and the impacts of infiltration basin features and vadose zone factors on water distributions. In this work, an ideal conceptual model was considered, and mathematical models were built using HYDRUS (2D/3D) software package version 2.05. A total of 138 numerical experiments were implemented under seven types of experimental conditions. The experimental data were analyzed with the aid of correlation and regression analysis. The results showed that infiltration basin features and vadose zone factors had various impacts on water distribution, low permeability formation had various effects on evaporation depending on its depth, and there were consistent, similar, or different variation trends between infiltration and recharge. In conclusion, it is recommended that when the vadose zones are to be chosen as an infiltration basin site, the trade-off among the infiltration, recharge, storage, and evaporation should be seriously considered. This paper may contribute to a better understanding of the vadose zone as a buffer zone for artificial recharge.

Numerical simulation of hydraulic properties of soil in the GSPAC system under variable water-levels

The effects of spatial variability and human factors on soil lead to complex soil hydraulic properties. In areas with highly variable water levels, it is impossible to use analytic expressions to accurately quantify and describe the process of moisture transport. In this study, the HYDRUS software package was used to calculate and simulate soil moisture transport under variable water levels by analyzing soil and underground water as an integrated system, and conducting in-situ monitoring tests on a large indoor soil trough. The results showed that: (1) the initial model verification achieved by adjusting the groundwater level revealed that when the groundwater dropped, the soil moisture in the vadose zone transitioned from balanced to unbalanced to balanced again; (2) the values and development trends of the negative pressure and water content of the soil as calculated by the model using adjusted parameters were consistent with those of the measured result, which indicated that the moisture transport model established in the GSPAC system was credible; and (3) the model established by the HYDRUS software package was able to effectively predict the soil moisture transport and infiltration dynamics.

Simulation of nitrate and potassium concentrations in soil solution using parametric models and Hydrus-2D

This study estimated the nitrate and potassium concentration in the soil solution of drainage lysimeter using the mathematical models developed by Vogeler et al. (1996) and Muñoz-Carpena et al. (2005) and the computational model Hydrus-2D, while comparing the simulated and observed data using statistical parameters. The cultivar used for the study was ‘Prata Gorutuba’. The experimental plots were six lysimeters of drainage. Fertigation was performed weekly. The mathematical models developed by Vogeler et al. (1996) and Muñoz-Carpena et al. (2005) were used to determine the specific concentration of a given ion (Ci). The Hydrus software was used to simulate the dynamics of nutrients. The concentrations of nitrate and potassium in the soil solution were estimated by the model of Vogeler et al. (1996), adapted to the linear type CEw-Ci ratio and simulated by the Hydrus model, resulting in an acceptable characterization of the distribution of these nutrients.

Comparison of recharge from drywells and infiltration basins: A modeling study

Drywells (DWs) and infiltration basins (IBs) are widely used as managed aquifer recharge (MAR) devices to capture stormwater runoff and recharge groundwater. However, no published research has compared the performance of these two engineered systems under shared conditions. Numerical experiments were conducted on an idealized 2D‐axisymmetric domain using the HYDRUS (2D/3D) software to systematically study the performance of a circular IB design (diameter and area) and partially penetrating DW (38 m length with water table > 60 m). The effects of subsurface heterogeneity on infiltration, recharge, and storage from the DW and IB under constant head conditions were investigated. The mean cumulative infiltration (μI) and recharge (μR) volumes increased, and the arrival time of recharge decreased with the IB area. Values of μI were higher for a 70 m diameter IB than an DW, whereas the value of μR was higher for a DW after 1-year of a constant head simulation under selected subsurface heterogeneity conditions. A comparison between mean μI, μR, and mean vadose zone storage (μS) values for all DW and IB stochastic simulations (70 for each MAR scenario) under steady-state conditions demonstrated that five DWs can replace a 70 m diameter IB to achieve significantly higher infiltration and recharge over 20 years of operation. Additional numerical experiments were conducted to study the influence of a shallow clay layer by considering an IB, DW, and a DW integrated into an IB. The presence of such a low permeable layer delayed groundwater recharge from an IB. In contrast, a DW can penetrate tight clay layers and release water below them and facilitate rapid infiltration and recharge. The potential benefits of a DW compared to an IB include a smaller footprint, the potential for pre-treatments to remove contaminants, less evaporation, less mobilization of in-situ contaminants, and potentially lower maintenance costs. Besides, this study demonstrates that combining both IB and DW helps to get the best out of both MAR techniques.

Water Movement through Soil under Drip Irrigation using Different Hydraulic Soil Models

Drip irrigation is one of the conservative irrigation techniques since it implies supplying water directly on the soil through the emitter; it can supply water and fertilizer directly into the root zone. An equation to estimate the wetted area in unsaturated soil is taking into calculating the water absorption by roots is simulated numerically using HYDRUS (2D/3D) software. In this paper, HYDRUS comprises analytical types of the estimate of different soil hydraulic properties. Used one soil type, sandy loam, with three types of crops; (corn, tomato, and sweet sorghum), different drip discharge, different initial soil moisture content was assumed, and different time durations. The relative error for the different hydraulic soil models was calculated and was compared with the model of Brooks and Corey, 1964. There was good agreement compared with different models. The Root Mean Square Error (RMSE) was (0.23) cm, while the relative error (- 1%) and (1) for modeling efficiency (EF) for wetted radius, but wetted depth was RMSE (0.99) cm, and the relative error was (4.5%), and EF was (1).

Assessment of potential groundwater contamination by ground source heat pump operation using solute transport models

Globally, over the past few decades, there has been a rapid increase in the use of ground source heat pump (GSHP) systems for heating and cooling purposes. Although these systems are more energy efficient than conventional air source heat pump systems, their association with potential groundwater contamination risks, e.g., the leakage of heat exchanger fluids like glycol, is a major concern. In this study, HYDRUS software was used to simulate the transportation of fluids from such systems into an aquifer. To better understand the transport environment, a geological survey was conducted and a > 50 m deep observation well was dug close to the GSHP installation site. To determine the physical properties of the soil, core samples were collected and analyzed; to determine the flow rate of the groundwater as well as the hydrological properties of the aquifer, measurements were conducted using a velocimeter that was installed in the borehole of the observation well. A laboratory column containing aquifer soil was used to determine drainage breakthrough curves. The hydrological parameters of the soil and the solute were used for the simulation under a virtual groundwater environment. The flow of groundwater resulted in the dispersion of the contaminant from its source, and its concentration was significantly reduced owing to degradation presumedly by biological activity. Additionally, two methods for the elimination of the contaminant from aquifers (enforced biodegradation and decontamination by pumping) were identified.

Using electromagnetic induction technology to identify atrazine leaching potential at field scale

Atrazine is an herbicide commonly used to control weeds in corn crop. Atrazine becomes an environmental concern when it moves off-site to surface and ground waters. Understanding how atrazine moves in the field is important for developing management controls. Electromagnetic induction (EMI) has been used to map certain contaminant transport at the field scale. This study was developed to evaluate the efficacy of EMI technology for identifying surface soil atrazine concentration in a corn crop field. The research was conducted in a corn silage field with silt, clay and loam soils at the U.S. Meat Animal Research Center (USMARC), Clay Center, NE – USA, and it was divided in three stages; i) EMI data collection and a response surface sampling design for collection of bulk soils and soil core samples, ii) atrazine transport parameters were obtained by Breakthrough Curves using the bulk soil and numerical adjustments using STANMOD (HYDRUS package), and iii) Modeling atrazine parameters through EMI signal data with posterior atrazine’s movement simulations through the soil using HYDRUS 2D. Atrazine’s retardation factor, partition coefficient, and transfer coefficient were strongly correlated with EMI signal exhibiting a strong correlation with apparent electrical conductivity (ECa). The low values for RMSE and RRMSE and the high values for Willmott and Pearson coefficients indicate EMI technology can be used to predict atrazine movement parameters. HYDRUS 2D quantitatively simulates the atrazine concentration leaching and how the temporal scale of this contamination would be. Combining EMI technology with HYDRUS 2D modeling provides researcher with additional information for developing better management practices for controlling atrazine movement to surface water; however, further studies are needed determine the effectiveness of this approach for other soil types.

Groundwater recharge from drywells under constant head conditions

Drywells are widely used as managed aquifer recharge devices to capture stormwater runoff and recharge groundwater, but little research has examined the role of subsurface heterogeneity in hydraulic properties on drywell recharge efficiency. Numerical experiments were therefore conducted on a 2D‐axisymmetric domain using the HYDRUS (2D/3D) software to systematically study the influence of various homogenous soil types and subsurface heterogeneity on recharge from drywells under constant head conditions. The mean cumulative infiltration (μI) and recharge (μR) volumes increased with an increase in the saturated hydraulic conductivity (Ks) for various homogeneous soils. Subsurface heterogeneity was described by generating ten stochastic realizations of soil hydraulic properties with selected standard deviation (σ), and horizontal (X) and vertical (Z) correlation lengths. After 365 days, values of μI, μR, and the radius of the recharge area increased with σ and X but decreased with Z. The value of μR was always smaller for a homogeneous than a heterogeneous domain. This indicates that recharge for a heterogeneous profile cannot be estimated with an equivalent homogeneous profile. The value of μR was always smaller than μI and correlations were highly non-linear due to vadose zone storage. Knowledge of only infiltration volume can, therefore, lead to misinterpretation of recharge efficiency, especially at earlier times. The arrival time of the wetting front at the bottom boundary (60 m) ranged from 21 to 317 days, with earlier times occurring for increasing σ and Z. The corresponding first arrival location can be 0.1–44 m away from the bottom releasing point of a drywell in the horizontal direction, with greater distances occurring for increasing σ and X. This knowledge is important to accurately assess drywell recharged performance, water quantity, and water quality.

Effects of subterranean termite nest architectures on earth embankment seepage and stability

Subterranean termites (Odontotermes formosanus Shiraki) that build nests in the soil matrices of earth embankments may adversely affect the stability of these structures in paddy farming regions of southern China. An adult termite nest comprises a primary chamber, fungus gardens, passageways, and other shelter tubes. These porous architectures enable high hydraulic conductivity and rapid groundwater flow. In this study, we performed a field survey to characterize these termite nest architectures and proposed a simulation method that estimates seepage and associated stability in termite-infested earth embankments. Three types of nest architectures—straight, siphon, and string—were investigated in situ. Groundwater flow and its relationship with earth embankment stability were analyzed using a numerical model based on the two-dimensional Richards equation in the HYDRUS software package. Results indicated that the presence of termite nests affected seepage zone geometry and substantially affected its phreatic line, seepage flux, and global and local stabilities of the earth embankment. In the cases examined here, the presence of termite nests resulted in a maximum factor of safety reduction of 17% along the downstream slope. The local instability zones of earth embankment, resulting from clogged termite nest passageways along the downstream slope, were also assessed.

Procena procesa kompostiranja u automatizovanom sistemu aerobne fermentacije na osnovu ključnih parametara

The poultry (broiler) industry is continuously increasing all over the world, therefore, the amount of waste generated in these facilities is also increasing. As a consequence of the above mentioned, the more efficient conversion of chicken manure to organic fertilizer is a key problem. The aims of the study are to investigate the changes in temperature and moisture content during composting of chicken manure in the oval tank fermentation system and to create a model for the evaluation of the performance of biodegradation processes. The moisture and temperature distribution models of the oval tank were created in Hydrus software. The results showed that the oval tank fermenter can be divided into two main zones. In the first zone, where the rate of biodegradation was relatively high, a heterogeneous temperature zone was found with continuously decreasing moisture content. The second zone was more homogenous in both temperature and moisture content. This stage represents the weak fermentation part of the technology and results in an elongated post fermentation section. Furthermore, statistically significant correlations were found between composting key parameters, such as ammonium content with temperature and organic matter content with organic nitrogen content. It was also concluded that the exact location of the manure turning and chopping mechanical system (MTCM) used for aeration had a high effect on the composting processes, as well as on the quality parameters of the mature compost.

Predicting Wetting Patterns in Soil from a Single Subsurface Drip Irrigation System

Soil wetted pattern from a subsurface drip plays great importance in the design of subsurface drip irrigation (SDI) system for delivering the required water directly to the roots of the plant. An equation to estimate the dimensions of the wetted area in soil are taking into account water uptake by roots is simulated numerically using HYDRUS (2D/3D) software. In this paper, three soil textures namely loamy sand, sandy loam, and loam soil were used with three different types of crops tomato, pepper, and cucumber, respectively, and different values of drip discharge, drip depth, and initial soil moisture content were proposed. The soil wetting patterns were obtained at every thirty minutes for a total time of irrigation equal to three hours. Equations for wetted width and depth were predicted and evaluated by utilizing the statistical parameters (model efficiency (EF), and root mean square error (RMSE)). The model efficiency was more than 95%, and RMSE did not exceed 0.64 cm for three soils. This shows that evolved formula can be utilized to describe the soil wetting pattern from SDI system with good accuracy. 

Capturing soil-water and groundwater interactions with an iterative feedback coupling scheme: new HYDRUS package for MODFLOW

Abstract. Accurately capturing the complex soil-water and groundwater interactions is vital for describing the coupling between subsurface–surface–atmospheric systems in regional-scale models. The nonlinearity of Richards' equation (RE) for water flow, however, introduces numerical complexity to large unsaturated–saturated modeling systems. An alternative is to use quasi-3-D methods with a feedback coupling scheme to practically join sub-models with different properties, such as governing equations, numerical scales, and dimensionalities. In this work, to reduce the nonlinearity in the coupling system, two different forms of RE are switched according to the soil-water content at each numerical node. A rigorous multi-scale water balance analysis is carried out at the phreatic interface to link the soil-water and groundwater models at separated spatial and temporal scales. For problems with dynamic groundwater flow, the nontrivial coupling errors introduced by the saturated lateral fluxes are minimized with a moving-boundary approach. It is shown that the developed iterative feedback coupling scheme results in significant error reduction and is numerically efficient for capturing drastic flow interactions at the water table, especially with dynamic local groundwater flow. The coupling scheme is developed into a new HYDRUS package for MODFLOW, which is applicable to regional-scale problems.

Drywell infiltration and hydraulic properties in heterogeneous soil profiles

Drywells are increasingly used to capture stormwater runoff for surface infiltration and aquifer recharge, but little research has examined the role of ubiquitous subsurface heterogeneity in hydraulic properties on drywell performance. Numerical experiments were therefore conducted using the HYDRUS (2D/3D) software to systematically study the influence of subsurface heterogeneity on drywell infiltration. Subsurface heterogeneity was described deterministically by defining soil layers or lenses, or by generating stochastic realizations of soil hydraulic properties with selected variance (σ) and horizontal (X) and vertical (Z) correlation lengths. The infiltration rate increased when a high permeability layer/lens was located at the bottom of the drywell, and had larger vertical and especially horizontal dimensions. Furthermore, the average cumulative infiltration (I) for 100 stochastic realizations of a given subsurface heterogeneity increased with σ and X, but decreased with Z. This indicates that the presence of many highly permeable, laterally extending lenses provides a larger surface area for enhanced infiltration than the presence of isolated, highly permeable lenses. The ability to inversely determine soil hydraulic properties from numerical drywell infiltration results was also investigated. The hydraulic properties and the lateral extension of a highly permeable lens could be accurately determined for certain idealized situations (e.g., simple layered profiles) using constant head tests. However, variability in soil hydraulic properties could not be accurately determined for systems that exhibited more realistic stochastic heterogeneity. In this case, the heterogeneous profile could be replaced with an equivalent homogeneous profile and values of an effective isotropic saturated conductivity (Ks) and the shape parameter in the soil water retention function (α) could be inversely determined. The average value of Ksfor 100 stochastic realizations showed a similar dependency to I on σ, X, and Z. Whereas, the average value of α had large confidence interval for soil heterogeneity parameters and played a secondary role in drywell infiltration. This research provides valuable insight on the selection of site, design, installation, and long-term performance of a drywell.

Improving the Estimation of Hydraulic and Thermal Properties of Heterogeneous Media via the Addition of Heat Loss

Core Ideas Heat loss is the main reason for water flux underestimation. Two methods were proposed to quantify the heat loss. More accurate hydraulic properties can be estimated with the addition of heat loss. Heat has been widely used to investigate water flow in soils and aquifers during the past few decades. However, heat loss as an important characteristic has not been well considered in laboratory heat‐tracing experiments. To evaluate the impact of heat loss on the estimation of hydraulic and thermal properties, a laboratory experiment was conducted using a sandbox packed with heterogeneous silica sand under steady‐state flow condition. Thermocouple probes were used to simultaneously measure the temperature inside and outside of the silica sand during the experiment. The measured temperature of the sand layer was used to estimate the hydraulic conductivities and longitudinal and transverse thermal dispersivities via curve fitting using HYDRUS software. We found that >50% of the sensible heat was dissipated into the shell of sandbox and the surrounding air rather than being absorbed by the sand. Two methods were then proposed to quantify the heat loss and to improve the accuracy of parameter estimation: (i) a conceptual heat balance method that accounted for the change in heat storage in different parts of the system and (ii) a physical process‐based method that described the thermodynamic processes of heat transfer among different parts of the system. On combining these two methods, the relative error between the estimated and measured water flux significantly decreased from 19% to nearly 2%. The results imply that the heat‐tracing method is capable of obtaining accurate hydraulic and thermal properties in a heterogeneous porous medium with the addition of heat loss.

Performance of HYDRUS-1D for simulating water movement in water-repellent soils

Soil water repellency affects soil water movement during infiltration significantly. The HYDRUS software has been popularly applied in soil water dynamics simulation for many years, but its performance in water-repellent (WR) soils has not been assessed thoroughly. Our objectives are to assess the performance of HYDRYUS-1D for cumulative infiltration (CI), wetting front (Zf), and volumetric soil water content (θv) during horizontal imbibition and vertical infiltration in wettable, slightly WR, and strongly WR soils. The key parameters of α and n in water retention curves were inversely estimated by RETension Curve software. The α and n were calibrated inversely until the observed data fitted the simulated values well enough. The α and n were then used for validation using three statistical parameters including relative root-mean-square error, R2, and Nash–Sutcliffe efficiency coefficient. The performances of calibration and validation for wettable, slightly, and strongly WR soils were good enough to be used for further simulations (RRMSE ≤20.2% for calibration and ≤21.1% for validation). Soil water movements for strongly WR soils of variable ponded depth during vertical infiltration were simulated. For Lou soil, as the ponded depth increased from 4 to 10 cm, the CI and Zfincreased 2.08 and 5.5 cm, respectively. The simulations for the other three soils also showed gradually increased CI and Zfvalues. In conclusion, the performances of HYDRUS-1D in four different soil types with changing WR levels were good, which confirmed the application of HYDRUS-1D in WR soils.

Implementation of Solute Transport in the Vadose Zone into the "HYDRUS Package for MODFLOW".

The "HYDRUS package for MODFLOW" is an existing MODFLOW package that allows MODFLOW to simultaneously evaluate transient water flow in both unsaturated and saturated zones. The package is based on incorporating parts of the HYDRUS-1D model (to simulate unsaturated water flow in the vadose zone) into MODFLOW (to simulate saturated groundwater flow). The coupled model is effective in addressing spatially variable saturated-unsaturated hydrological processes at the regional scale. However, one of the major limitations of this coupled model is that it does not have the capability to simulate solute transport along with water flow and therefore, the model cannot be employed for evaluating groundwater contamination. In this work, a modified unsaturated flow and transport package (modified HYDRUS package for MODFLOW and MT3DMS) has been developed and linked to the three-dimensional (3D) groundwater flow model MODFLOW and the 3D groundwater solute transport model MT3DMS. The new package can simulate, in addition to water flow in the vadose zone, also solute transport involving many biogeochemical processes and reactions, including first-order degradation, volatilization, linear or nonlinear sorption, one-site kinetic sorption, two-site sorption, and two-kinetic sites sorption. Due to complex interactions at the groundwater table, certain modifications of the pressure head (compared to the original coupling) and solute concentration profiles were incorporated into the modified HYDRUS package. The performance of the newly developed model is evaluated using HYDRUS (2D/3D), and the results indicate that the new model is effective in simulating the movement of water and contaminants in the saturated-unsaturated flow domains.

Simulation of irrigation return flow from a Triticale farm under sprinkler and furrow irrigation systems using experimental data: A case study in arid region

Irrigation return flow is an important and hard-to-estimate component of the groundwater balance equation. In this study, irrigation return flow from a Triticale farm under sprinkler and furrow irrigation systems was investigated in arid region. For the sake of accuracy, high-resolution (both temporally and spatially) datasets were provided through ten monitoring wells (eight two-meter-deep and two six-meter-deep monitoring wells) equipped with totally 76 soil moisture sensors. Moreover, dual crop coefficient approach was used for estimation of evapotranspiration in each experimental field due to its adaptability with short-interval data. The datasets were used for calibration and validation of HYDRUS-1D software over about six months of Triticale growth period. The results showed an acceptable agreement between measured and simulated water content in each soil layer of furrow- (with RMSE and MAE equal to 0.035 and 0.031 cm3/cm3, respectively) and sprinkler-irrigated (with RMSE and MAE equal to 0.024 and 0.020 cm3/cm3, respectively) fields. HYDRUS simulations were also used for estimation of irrigation return flow. Results showed that in furrow-irrigated field, about 13.3 percent of inflows (including irrigation and precipitation) returns back to groundwater aquifer as irrigation return flow. However, that was negligible in sprinkler-irrigated field. The rationale behind different irrigation flows obtained for each experimental field was investigated using water balance components obtained by HYDRUS software. It was revealed that total water application depth and evapotranspiration was almost the same for both experimental fields. However, the intrinsic difference between the application intervals and in turn, application depths in each interval provoked more irrigation return flow in furrow-irrigated field. Eventually, sensitivity assessment was done to quantify the impact of soil hydraulic parameters on return flow. The results showed that the parameters which have the most impact on total amount of return flow are θs and n for furrow-irrigated field whereas in the case of sprinkler-irrigated field parameters showed inconsiderable impact on return flow. The fact which has root in different initial water content of each experimental field.