Water Uptake Parameters Research Articles

Carbonation process of commercial lime mortars vs cement-based mortars: Comparative analysis of textural differences, strength and durability

The present study analyses 5 commercially available mortars (Italian, German and Hungarian brands) under various conditions such as dry, water-saturated and freeze-thaw. Laboratory tests assessed specimens' physical properties and carbonation process 28 days after casting using EN guidelines. The workability, density, ultrasonic pulse velocity, water uptake, and strength parameters were measured. The bulk density of the studied mortars was between 1514-1840 kg/m3, indicating the variations in composition and porosity, and it correlates well with the measured P-velocities of 1939 m/s to 2649 m/s. The compressive strength of cubic standard test specimens was between 1.8 and 8.4 MPa, suggesting different mineralization and carbonation processes, clearly marking the presence of the Portland cement phase. A large scatter of physical parameters and various durability marks water-saturated and freeze-thaw-affected mortars. Carbonation and curing conditions can cause significant parameter differences in lime-based mortars. CO2 sequestration depends on mortar composition, textural and micro-fabric, and environmental conditions.

A probabilistic framework for assessing the hydrological impact of Faidherbia albida in an arid area of Senegal

The Faidherbia tree (Faidherbia albida) is frequently used as an intercrop in Sahelian agroforestry parklands due to its multi-purpose advantages and reverse phenology. However, its effect upon the water balance remains unclear, due to the challenges in directly measuring water fluxes in the underlying vadose zone. Mechanistic hydrological models can be inversely calibrated on transient observations and used to partition different hydrological components, but the computational burden of the analysis can become impractical if the model itself is computationally expensive. To overcome this limitation, and to provide novel insights into the hydrological role of Faidherbia, we combine a low-fidelity, one-dimensional hydrological model (HYDRUS-1D) with a kriging-based correction function to emulate the response of a high-fidelity, two-dimensional axisymmetric description of the system (HYDRUS-2D). Multiannual measurements of soil moisture and sap flow in a Senegal agroforestry parkland are used in conjunction with Bayesian inference to calibrate the resulting validated multifidelity surrogate, and to inversely estimate soil hydraulic and root water uptake parameters. Results show that the model can reproduce observations with good accuracy and limited uncertainty for both the calibration and the validation phases, and also confirm the phreatophytic behaviour of Faidherbia by indicating the existence of a moderately compensated root water uptake. Moreover, a local sensitivity analysis suggests that a fully compensated uptake could potentially reduce groundwater recharge by 13%. Interestingly, estimated soil hydraulic parameters hint at the possibility of root-induced changes in soil hydraulic properties that mimic preferential and/or macropore flow, resulting in sustained recharge fluxes (≈ 26% of the annual precipitation). The analysis indicates that overall, Faidherbia could have a net positive effect upon the water balance in arid areas.

Investigating Near-Surface Hydrologic Connectivity in a Grass-Covered Inter-Row Area of a Hillslope Vineyard Using Field Monitoring and Numerical Simulations

The interplay of surface and shallow subsurface fluxes plays a critical role in controlling water movement in hillslope agroecosystems and impacting soil and plant health during prolonged dry periods, demonstrating a need for in-field monitoring. This study was conducted for two years (2021–2022) by combining field monitoring of the grass-covered inter-row area (passive wick lysimeter, surface runoff, and meteorological data), laboratory determination of soil hydraulic properties (SHPs), and numerical modeling with the aim to explore near-surface fluxes at the SUPREHILL Critical Zone Observatory (CZO) located on a hillslope vineyard. Additionally, sensitivity analysis for basic root water uptake (RWU) parameters was conducted. The model was evaluated (R2, RMSE, and NSE) with lysimeter (hillslope) and runoff (footslope) data, producing good agreement, but only after the inverse optimization of laboratory estimated hydraulic conductivity was conducted, demonstrating that adequate parameterization is required to capture the hydropedological response of erosion-affected soil systems. Results exhibit the dependence of runoff generation on hydraulic conductivity, rainfall, and soil moisture conditions. The data suggest different soil-rewetting scenarios based on temporal rainfall variability. Sensitivity analysis demonstrated that Leaf Area Index (LAI) was the most responsive parameter determining the RWU. The study offers an approach for the investigation of fluxes in the topsoil for similar sites and/or crops (and covers), presenting the methodology of self-constructed soil–water collection instruments.

Mechanical Scarification Influence on Gleditsia assamica Bor Water Uptake and Germination

Physical dormancy is a typical kind of dormancy in Fabaceae species, including Gleditsia assamica. Physical dormancy is caused by the impermeability of the seed coat and can be alleviated, among others, by mechanical scarification. Previous studies on mechanical scarification effect on G. assamica seed focus only on its germination parameter without regard to its effect on seed water upatke. As germination is initiated with water uptake, current study aims to understand the treatment effect on both of seed water uptake and germination parameters. Tetrazolium dyeing and seed weight measurement trials were conducted to study the seed water uptake. Meanwhile, a germination test is conducted to investigate the treatment's influence on the seed germination parameters. This study shows that mechanical scarification can enhance G. assamica seed water uptake. The treatment was also significantly improve final germination percentage and germination speed index. This study result gives us a clearer understanding of the effect of mechanical scarification to alleviate G. assamica dormancy and germination, which will be advantageous to the species conservation and domestication efforts.

Foliar Application of Boron Nanoencapsulated in Almond Trees Allows B Movement Within Tree and Implements Water Uptake and Transport Involving Aquaporins.

Nanotechnology brings to agriculture new forms of fertilizer applications, which could be used to reduce environmental contamination and increase efficiency. In this study, foliar fertilization with nanoencapsulated boron (B) was studied in comparison to an ionic B (non-encapsulated) application in young B-deficient almond trees grown under a controlled environment. B movement within the plant in relation to the leaf gas exchange, water relations parameters, and root hydraulic conductance was measured. Also, the expression of aquaporins (AQPs) [plasma membrane intrinsic protein (PIP) and tonoplast intrinsic protein (TIP)] was studied in relation to water uptake and transport parameters to establish the effectiveness of the different B treatments. The obtained results were associated with a high concentration of observed B with nanoencapsulated B, provided by the higher permeability of carrier nanovesicles, which allowed B to reach the cell wall more efficiently. The increases in water uptake and transport obtained in these plants could be related to the role that this element played in the cell wall and the relationship that it could have in the regulation of the expression of AQPs and their involvement in water relations. Also, an increase in the expression of PIPs (mainly PIP2.2) to the applied nanoencapsulated B could be related to the need for B and water transport, and fine regulation of TIP1.1 in relation to B concentration in tissues provides an important feature in the remobilization of B within the cell.

Water absorption parameters of glass/epoxy composites based on dimension effect

In this study, the water uptake parameters of S glass/epoxy samples have been assessed experimentally. The glass/epoxy specimens were manufactured by the vacuum assisted resin transfer method (VARIM) have been kept in distilled water and sea water at 25°C and 70°C temperatures for 1000 hours in a hydrothermal aging cabin. The water gain behavior of samples with different length/width (L/w) ratios has been investigated based on criteria such as different water types and different temperatures. Furthermore, the water uptake trend of samples has been assessed analytically based on the Fick’s law in addition to the experimental method. The results have shown that the L/w ratio, water type, and temperature have an important influence on the water gain character of glass/epoxy composites. The experimental weight measurements showed that temperature increase was caused to more water absorption in both water types. Furthermore, it was noted the increase in L/w ratio was caused to more water sorption. Moreover, experimental and analytical results have shown that water intake trends consistent in both methods.

Compensated non‐linear root water uptake model and identification of soil hydraulic and root water uptake parameters*

AbstractThe improvement in soil and root parameterization is a key to enhance the root zone moisture depletion pattern prediction capability. In the present study, a new compensated non‐linear root water uptake (RWU) model is developed to analyse moisture flow under various crop growth and soil conditions. This is achieved by introducing a water stress index in the calibrated non‐linear RWU model that takes care of RWU compensation. The present study also deals with the identifiability of soil hydraulic and RWU parameters using soil moisture and percolation data with an inverse approach. For parameter estimation, the numerical model has been coupled with a genetic algorithm‐based optimizer. The efficacy of the coupled simulation‐optimization model is tested for wheat (Triticum aestivum) crops grown in loamy, sandy clay loam, and sandy loam soil. The study shows that the RWU is less sensitive to soil moisture dynamics in sandy loam soil due to predominant vertical flow. Further, these parameters were estimated for four major Indian crops, that is, berseem (Trifolium alexandrinum), wheat, maize (Zea mays), and pearl millet (Pennisetum glaucum). In soils of higher hydraulic conductivity, the inverse approach was found to be ill‐posed in estimating RWU and soil parameters using only soil moisture information. Hence, for such soils, both soil moisture and percolation data are necessary for estimating these parameters uniquely.

Quaternary polymethacrylate−magnesium aluminum silicate film formers: Stability studies for tablet coatings

The objective of this work was to investigate the long-term stability of quaternary polymethacrylate-magnesium aluminum silicate (QPM-MAS) nanocomposite film-coated tablets compared to that of QPM-coated tablets. QPM- and QPM-MAS-coated tablets prepared without or with a curing process at 60 °C for 12 h were stored without packaging under ambient (26 ± 2 °C, 50% relative humidity (RH)) and accelerated (45 ± 1 °C, 75% RH) conditions. The outer morphology, water uptake and drug release parameters (lag time and drug release rate) were investigated. The results showed that the QPM-coated tablets prepared without or with curing (60 °C for 12 h) presented darker brown and shinier films, whereas the QPM-MAS 4:0.75-coated tablets showed minor change in color and appearance after storage under both conditions for 4 months. The QPM- and QPM-MAS-coated tablets experienced a decrease in % change in wet mass and drug release rate, and an extension in lag time when stored under both conditions. Changes in the water uptake and drug release of the coated tablets were also observed when a curing process was involved. This finding suggested that temperature and humidity strongly influenced further fusion of the QPM particles, even though MAS could interact with QPM to form nanocomposites in the coated films. Therefore, temperature control and water vapor-resistant packaging are necessary for maintaining the long-term stability of the QPM and QPM-MAS film-coated formulations.

Estimation of root water uptake and soil hydraulic parameters from root zone soil moisture and deep percolation

For efficient irrigation management practices, an accurate prediction of water uptake in the root zone and soil information are foremost important. The present study deals with the identification and estimation of root water uptake (RWU) and soil hydraulic parameters using inverse modeling. These parameters were estimated by minimizing the difference between observed and model simulated soil moisture and deep percolation during the crop growth period. The linked simulation optimization model is tested for three different objective functions using hypothetically generated observed data. Results indicate that the optimizer with objective function defined by soil moisture, failed to provide unique estimate of RWU and soil hydraulic parameters. Further, it has been observed that with the objective function defined by deep percolation, soil hydraulic parameters were uniquely estimated but RWU parameter was not estimated accurately. However, with the objective function, that includes both soil moisture and deep percolation, these parameters were uniquely estimated. A Lysimeter experiments were conducted with four crops i.e. berseem (Trifolium alexandrinum), wheat (Triticum aestivum), maize (Zea mays) and pearl millet (Pennisetum glaucum). Daily monitoring of soil moisture and deep percolation along with soil and crop parameter measurements were done for model validation. Inversely estimated soil hydraulic parameters were found to be in close agreement with laboratory obtained values. The results indicate that specifically for soils with high hydraulic conductivity, the information about deep percolation along with soil moisture is necessary for inverse estimation of root and soil parameters simultaneously. The moisture depletion pattern and deep percolation corresponding to optimized parameters for these crops were found to be in close agreement with observed values.

Effect of Water Table Depth on Soybean Water Use, Growth, and Yield Parameters

Water table contribution to plant water use is a significant element in improving water use efficiency (WUE) for agricultural water management. In this study, lysimeter experiments were conducted in a controlled greenhouse environment to investigate the response of soybean water uptake and growth parameters under four different water table depths (WTD) (30, 50, 70, and 90 cm). Soybean crop water use, WUE, and root distribution under the different WTD were examined. For 30, 50, 70, and 90 cm of WTD treatments, the average water table contributions were 89, 83, 79, and 72%; the grain yields were 15.1, 10.5, 14.1, and 17.2 g/lys.; and the WUEs were 0.22, 0.18, 0.25, and 0.31 g/lys./cm, respectively. Further analysis of the root mass and proportional distribution among the different soil layers illustrated that the lysimeters with 70 and 90 cm WTD had greater root mass with higher root distribution at 40–75 cm of the soil layer. The results indicated that 70 and 90 cm of constant WTD can yield higher grain yield and biomasses with greater WUE and better root distribution than the irrigated or shallow WTD treatments.

Swelling behaviors of novel magnetic semi-IPN hydrogels and their application for Janus Green B removal

Novel magnetic hydrogels based on acrylamide/2-acrylamido-2-methyl-1-propanesulfonic acid/poly(ethylene glycol) were prepared by free radical solution polymerization using ammonium persulfate/N,N,N′,N′-tetramethylethylenediamine as redox initiating pair in the presence of poly(ethylene glycol) dimethacrylate as a cross-linker. In this study, the water uptake and dye sorption performances of a series of novel magnetic hydrogel sorbents were investigated. For the preparation of magnetic polymeric hydrogels and semi-IPNs, they were loaded with iron (Fe2+, Fe3+) ions. Dynamic swelling tests were applied at 25 °C gravimetrically. According to obtained data, swelling kinetics parameters and diffusion mechanisms were calculated. The magnetic hydrogels synthesized in this study showed high water absorbency. Some water uptake and diffusion parameters were calculated, and they were discussed for the hydrogels prepared under various formulations. Structural characterization of polymers was completed with Fourier transform infrared spectroscopy analysis. Scanning electron microscopy images were taken for the determination of surface porosity of hydrogels and semi-IPNs. For adsorption studies, Janus Green B was chosen as model molecule. It was determined that semi-IPNs and hydrogels adsorbed Janus Green B from aqueous solutions at high levels. Consequently, the hydrogels developed in this study could serve for potential applications in wastewater treatment for water and dye uptake.

Optimum Turf Grass Irrigation Requirements and Corresponding Water- Energy-CO2 Nexus across Harris County, Texas

Harris County is one of the most populated counties in the United States. About 30% of domestic water use in the U.S. is for outdoor activities, especially landscape irrigation and gardening. Optimum landscape and garden irrigation contributes to substantial water and energy savings and a substantial reduction of CO2 emissions into the atmosphere. Thus, the objectives of this work are to (i) calculate site-specific turf grass irrigation water requirements across Harris County and (ii) calculate CO2 emission reductions and water and energy savings across the county if optimum turf grass irrigation is adopted. The Irrigation Management System was used with site-specific soil hydrological data, turf crop water uptake parameters (root distribution and crop coefficient), and long-term daily rainfall and reference evapotranspiration to calculate irrigation water demand across Harris County. The Irrigation Management System outputs include irrigation requirements, runoff, and drainage below the root system. Savings in turf irrigation requirements and energy and their corresponding reduction in CO2 emission were calculated. Irrigation water requirements decreased moving across the county from its north-west to its south-east corners. However, the opposite happened for the runoff and excess drainage below the rootzone. The main reason for this variability is the combined effect of rainfall, reference evapotranspiration, and soil types. Based on the result, if the average annual irrigation water use across the county is 25 mm higher than the optimum level, this will result in 10.45 million m3 of water losses (equivalent water use for 30,561 single families), 4413 MWh excess energy use, and the emission of 2599 metric tons of CO2.

Modeling Moisture Flow in Root Zone: Identification of Soil Hydraulic and Root Water Uptake Parameters

AbstractThe present study is concerned with the analysis of moisture flow in the crop root zone and estimation of soil hydraulic and root water uptake parameters from soil moisture depletion data u...

Quantifying Soil Water and Root Dynamics Using a Coupled Hydrogeophysical Inversion

Core Ideas A novel coupled inversion algorithm estimated soil and root parameters. Electrical resistivity data were used to identify root and soil hydraulic properties. A unique root distribution was estimated despite input error and data density. This noninvasive technique can capture root dynamics in a variety of settings. Plot‐ to field‐scale root distribution data are relatively rare and difficult to measure with traditional methods. Nevertheless, these data are needed to accurately model root water uptake (RWU) processes within agronomic, hydrologic, and terrestrial biosphere models. New tools are needed to effectively observe root distributions and model dynamic root growth processes. In the past decade, geophysical tools have increasingly been used to study the vadose zone, and hydrogeophysical inversions have shown promise to noninvasively characterize water dynamics. In such an approach, the hydrology is modeled and hydrological data are inverted with the geophysical data, constraining the geophysical inversion results and decreasing uncertainty and the number of nonunique solutions. In this study, we developed and tested a coupled hydrogeophysical inversion approach that uses electrical resistivity data to estimate soil hydraulic, petrophysical, and root dynamic parameters. This builds on prior research that used either a coupled hydrogeophysical inversion to estimate soil hydraulic parameters only, or a hydrological inversion to estimate root distribution or root water uptake parameters. Our results indicate that under the conditions tested, this approach accurately captures root water dynamics and soil hydraulic parameters. This opens up opportunities to noninvasively image a variety of root distributions and soil systems, better understand the dynamics of RWU processes, and improve estimates of transpiration for systems models.

A Study of influence on sulfonated TiO2-Poly (Vinylidene fluoride-co-hexafluoropropylene) nano composite membranes for PEM Fuel cell application

The present work describes the sulfonated Titania directly blended with Poly (Vinylidene fluoride-co-hexafluoropropylene) as a host polymer by solvent casting technique for PEM fuel cell application. Characterization studies such as FT-IR, SEM, EDX, AFM, Proton conductivity, contact angle measurement, IEC, TG, water uptake, tensile strength were performed by for synthesized proton conducting polymer electrolytes. The maximum proton conductivity value was found to be 3.6×10−3S/cm for 25wt% sulfonated Titania based system at 80°C. The temperature dependent proton conductivity of the polymer electrolyte follows an Arrhenius relationship. Surface morphology of the composite membranes was investigated by tapping mode. Thermal stability of the system was studied by TG analysis. The fabricated composite membranes with high proton conductivity, good water uptake and IEC parameters exhibited a maximum fuel cell power density of 85 Mw/cm2for PEM fuel cell application.

Theoretical methodology for calculating water uptake and ionic exchange capacity parameters of ionic exchange membranes with applications in fuel cells

The water uptake (WU) and ionic exchange capacity (IEC) are important parameters for proton exchange membranes (PEMs), WU represents their total water content, while IEC is the measure of the ability of the membrane to facilitate movement of H30+ ions, located in the aqueous environment, through the −SO3− sulfonyl groups anchored in their structure. IEC is also the measure of relative concentration of acid groups within polymer electrolyte membrane. According to the vehicle mechanism of proton transport, an appropriate amount of water content and a suitable value of IEC in PEMs are necessary for achieving high proton conductivity. In this work, studies based on density functional theory (DFT), molecular mechanics (MM) and dynamics molecular (DS) were realized in order to develop a theoretical methodology to obtain these parameters. Our proposal considers the ionomer, the solvation medium and the interactions between the ionomer and water molecules. The methodology is applied to structures of sulfonated poly(ether-imide) (SPEI) with (–SO3H)n (n = 1, … 6) groups. These structures were built and optimized aiming to obtain above properties as a function of the number of sulfonyl groups. The comparative study demonstrates the SPEI with four sulfonyl groups is the polymer having better properties for successful operation in Fuel Cell.

Optimization of water uptake and photosynthetic parameters in an ecosystem model using tower flux data

The soil water stress factor (fw) and the maximum photosynthetic carboxylation rate at 25°C (Vcmax) are two of the most important parameters for estimating evapotranspiration and carbon uptake of vegetation. Ecologically these two parameters have different temporal variations and thus their optimization in ecosystem models poses a challenge. To minimize the temporal scale effect, we propose a three-stage approach to optimize these two parameters using an ensemble Kalman filter (EnKF), based on observations of latent heat (LE) and gross primary productivity (GPP) fluxes at three flux tower sites in 2009. First, the EnKF is applied daily to obtain precursor estimates of Vcmax and fw. Then, Vcmax is optimized at different time scales, assuming fw is unchanged from the first step. The best temporal period is then determined by analyzing the coefficient of determination (R2) of GPP and LE between simulation and observation. Finally, the daily fw value is optimized for rain-free days corresponding to the Vcmax curve from the best temporal period. We found that the variations of optimized fw are largely explained by soil water content in the summer. In the spring, the optimized fw shows a smooth increase following the rise of soil temperature, indicating that fw may respond to the development of fine roots, which is related to the amount of accumulated heat in the soil. The optimized Vcmax generally follows a pattern of a rapid increase at the leaf expansion stage in the spring, small variation in summer, and an abrupt decrease at foliage senescence. With eddy covariance fluxes data, data assimilation with a EnKF can retrieve the seasonal variations of water uptake and photosynthetic parameters in an ecosystem model, and such gives clues on how to model forest responses to water stress.

Effects of benzoyl peroxide on some properties of composites based on hemp and natural rubber

The obtaining and characterization of polymer composites based on natural rubber and hemp, in which the elastomer crosslinking has been achieved with benzoyl peroxide, are presented. The mechanical characteristics, gel fraction, crosslink density, water uptake swelling parameters and FTIR of the composites based on natural rubber and hemp fiber vulcanized by dibenzoyl peroxide have been investigated as a function of the hemp content. The hardness, modulus at 100 % elongation, tearing strength, tensile strength and elongation at break have been improving with the increasing of fiber content in composites materials due to the better interaction of fiber in natural rubber composites. These results indicate that hemp has a reinforcing effect on natural rubber. Gel fraction value is over 95 % for all blends and varies irregularly depending on the amount of hemp in the composites. The crosslinking density (ν) of samples increases as the amount of hemp in blends increases, because hemp act as a filler in natural rubber blends and leads to reinforcement of the blends. The water uptake and swelling parameters also increases with the increasing of the amount of fiber content, because of the hemp hydrophilic characteristics.

Aerosol mixing state, hygroscopic growth and cloud activation efficiency during MIRAGE 2006

Abstract. Observations of aerosol hygroscopic growth and CCN activation spectra for submicron particles are reported for the T1 ground site outside of Mexico City during the MIRAGE 2006 campaign. κ-Köhler theory is used to evaluate the characteristic hygroscopicity parameter, κ*, for the CCN active aerosol population using both size-resolved HTMDA and size-resolved CCNc measurements. Organic mass fractions (forg) are evaluated from size-resolved aerosol mass spectrometer (AMS) measurements, from which predictions of the hygroscopicity parameter are compared against κ*. Strong diurnal changes in aerosol water uptake parameters and aerosol composition are observed. We find that new particle formation (NPF) events are correlated with an increased κ* and CCN-active fraction during the daytime, with greater impact on smaller particles. During NPF events, the number concentration of 40 nm particles acting as CCN at 0.51% ± 0.06% supersaturation can surpass by more than a factor of two the corresponding concentrations of 100 nm particles. We also find that at 06:00–08:00 LT throughout the campaign, fresh traffic emissions result in substantial changes to the chemical distribution of the aerosol, with on average 65% externally mixed fraction for 40 nm particles and 30% externally mixed fraction for 100 nm particles, whereas at midday nearly all particles of both sizes can be described as "internally mixed". Average activation spectra and growth factor distributions are analyzed for different time periods characterizing the daytime (with and without NPF events), the early morning "rush hour" and the entire campaign. We show that κ* derived from CCNc measurements decreases as a function of size during all time periods, while the CCN-active fraction increases as a function of size. Size-resolved AMS measurements do not predict the observed trend for κ* versus particle size, which can be attributed to unresolved mixing state and the presence of refractory material not measured by the AMS. Measured κ* typically ranges from 0.2 to 0.35, and organics typically make up 60–85 % of the aerosol mass in the size range studied. We show that κAMS is able to describe CCN concentrations reasonably well, provided mixing-state information is available, especially at the highest CCN concentrations. This is consistent with other CCN studies carried out in urban environments, and is partly due to the fact that the highest CCN concentrations occur during the daytime when the aerosol is internally mixed. During the early morning rush hour, however, failing to account for the aerosol mixing state results in systematic overestimation of CCN concentrations by as much as 50–100% on average.

Simultaneous Estimation of Soil Hydraulic and Root Distribution Parameters from Lysimeter Data by Inverse Modeling

Weighable lysimeters are powerful measurement systems for identifying soil hydraulic processes and properties, because the boundary fluxes (precipitation, actual evapotranspiration, and seepage across the bottom) can be determined very precisely. However, root water uptake by plants and the soil water flux are interrelated. Thus, the simultaneous estimation of root water uptake parameters and soil hydraulic parameters from macroscopic state observations is a challenge. In this study we investigated the possibility of simultaneously estimating root water uptake and soil hydraulic parameters by inverse simulation of soil water flow in monolithic lysimeters under atmospheric boundary conditions. We used the Richards equation and a macroscopic root water uptake model to simulate the processes. The amount of information needed for the unique identification of parameters was analyzed and the magnitude of their uncertainties was investigated. To check the principal feasibility of our approach, we first examined synthetic data sets for different scenarios and instrumentation campaigns that differed in their information content and complexity of soil properties. The investigations of synthetic data showed that for homogeneous profiles, cumulative outflow and profile-averaged water content data contained enough system information to allow the simultaneous estimation of soil hydraulic properties and root-distribution parameters. In contrast, for soil profiles consisting of two layers, unique soil hydraulic parameters and the correct rooting depth could only be estimated if matric potential measurements from both layers were included in the objective function. To test the procedure with real data, soil hydraulic properties of the grass-reference lysimeter at Wagna (Austria) were estimated using actual measurements. Water dynamics in the lysimeter could be described well by an effective parameterization assuming a homogeneous soil profile. Furthermore, the system behavior under different boundary conditions could be predicted adequately with the estimated parameters.