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Tarik Ben Abdelouahab - One of the best experts on this subject based on the ideXlab platform.
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An evaporation test based on Thermal Infra Red Remote-Sensing to select appropriate soil Hydraulic properties
Journal of Hydrology, 2009Co-Authors: Gilles Boulet, Bernard Mougenot, Tarik Ben AbdelouahabAbstract:Pedotransfer functions are the most widely used method to estimate common soil Hydraulic properties at regional scale. Since they rely on an empirical link between textural and structural soil properties observed in the laboratory on undisturbed soil samples, one must check whether the pedotransfer functions built elsewhere also apply to the location of interest. Alternative methods to laboratory analysis, such as infiltration tests, exist but are difficult to carry out at large scales. Here we propose a method for selecting appropriate soil Hydraulic properties based on the physical link between the soil water diffusion properties and the plant water stress, which has been named the “evaporation test”. It consists in (i) detecting water stress from remote sensing data in the Thermal Infra Red spectrum and a simulated unstressed surface temperature, then (ii) estimating the date of the last irrigation/rainfall event, the water content at the end of this irrigation/rainfall event, the unstressed evapotranspiration rate and the average root depth and (iii) reducing the range of possible values for the Hydraulic Parameters to those that compute a time-to-stress that is consistent with the observed one, i.e. the difference between the observed water stress date and the date of the end of the last irrigation/rainfall event. The performance of this method is then checked for two sites within the frame of the SudMed and SALSA experiments by comparing the resulting properties to those obtained by other methods, namely the Beerkan infiltration test and the most commonly used pedotransfer functions. While not providing a unique set of Hydraulic properties, the “evaporation test” is a good mean to refine the range of appropriate Hydraulic Parameter values at the scale of the Thermal Infra Red data.
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An evaporation test based on thermal infra red remote-sensing to select appropriate soil Hydraulic properties
Journal of Hydrology, 2009Co-Authors: Gilles Boulet, Bernard Mougenot, Tarik Ben AbdelouahabAbstract:Pedotransfer functions are the most widely used method to estimate common soil Hydraulic properties at regional scale. Since they rely on an empirical link between textural and structural soil properties observed in the laboratory on undisturbed soil samples, one must check whether the pedotransfer functions built elsewhere also apply to the location of interest. Alternative methods to laboratory analysis, such as infiltration tests, exist but are difficult to carry out at large scales. Here we propose a method for selecting the appropriate Hydraulic properties based on the physical link between the soil water diffusion properties and the plant water stress, which has been named the "evaporation test". It consists in (i) detecting water stress from remote-sensing data in the Thermal Infra Red spectrum and a simulated unstressed surface temperature, then (ii) estimating the date of the last irrigation/rainfall event, the water content at the end of this irrigation/rainfall event, the unstressed evapotranspiration rate and the average root depth and (iii) reducing the range of possible values of the Hydraulic Parameters to those that compute a time-to-stress that is consistent with the observed one, i.e. the difference between the observed water stress date and the date of the end of the last irrigation/rainfall event. The performance of this method is then checked for two sites within the frame of the SudMed and SALSA experiments by comparing the resulting properties to those obtained by other methods, namely the Beerkan infiltration test and the most commonly used pedotransfer functions. While not providing a unique set of Hydraulic properties, the "evaporation test" is a good mean to refine the range of appropriate Hydraulic Parameter values at the scale of the Thermal Infra Red data.
Binayak P. Mohanty - One of the best experts on this subject based on the ideXlab platform.
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Reduction of feasible Parameter space of the inverted soil Hydraulic Parameter sets for Kosugi model.
Soil Science, 2013Co-Authors: Joseph Alexander Paul Pollacco, Binayak P. Mohanty, Paolo Nasta, José M. Soria-ugalde, Rafael Angulo-jaramillo, Laurent Lassabatere, Nunzio RomanoAbstract:Effective soil Hydraulic Parameters of soil vegetation atmo- sphere transfer (SVAT) models can be derived in a cost-efficient way by inverse modeling. Nevertheless, a serious drawback of SVAT models based on Richards' equation is that they require as many as five unex- ploited correlated Hydraulic Parameters. To reduce the feasible parame- ter space, we propose a method to prevent nonphysical combinations of soil Hydraulic Parameter sets obtained by optimization. We adopt the soil Hydraulic analytical model by Kosugi because it enables the feasible Parameter space to be reduced by predicting Parameter σ from Rm, which are the variance and mean of the log-transformed soil pore ra- dius, respectively. To further decrease the Parameter space, we derive two models to predict saturated Hydraulic conductivity, Ks, from three or four Kosugi soil water retention Parameters, respectively. These two models are based on the combination of the Hagen-Poiseuille and Darcy equations that use three semiempirical Parameters (τ1, τ2, and τ3) cali- brated on large UNSODA and HYPRES databases. Our derived models are compared with a version of the Mishra and Parker (1990. Ground Water. 28:775-777) Ks model being modified to account for the pa- rameters of Kosugi's relationships. The results show that the uncertain- ties of the developed Ks model are comparable to the uncertainties of Ks measurements. Moreover, the developed Ks model outperforms the Mishra and Parker model. Therefore, the developed method will enable one to substantially reduce the feasible range of the inverted Kosugi's Hydraulic Parameters.
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On topographic controls of soil Hydraulic Parameter scaling at hillslope scales
Water Resources Research, 2012Co-Authors: Raghavendra B. Jana, Binayak P. MohantyAbstract:[1] Most upscaling efforts for soil Hydraulic Parameters developed thus far have opted to ignore the effect of topography in their derivation of effective Parameter values. This approach, which considers a flat terrain with no lateral flows, is reasonable as long as the coarser support dimensions are of the order of a few hundred meters. In such a scenario, the upscaled characteristics of the Parameters are governed predominantly by the texture and structure of the soil in the domain. However, when upscaling fine-scale Hydraulic Parameter data to much larger extents (hillslope scales and beyond), topography plays a bigger role and can no longer be ignored. Efforts to model hydrologic processes and phenomena, with particular emphasis on those occurring in the unsaturated zone, are conducted at various scales. We present here a study to isolate the influence of topographic variations on the effective, upscaled soil Hydraulic Parameters under different hillslope configurations. The power-averaging operator algorithm was used to aggregate fine-scale soil Hydraulic Parameters to coarser resolutions. Hydrologic scenarios were simulated using HYDRUS-3D for four different topographic configurations under different conditions to test the validity of the upscaled soil Hydraulic Parameters. The outputs from the simulations (fluxes and soil moisture states) were compared across multiple scales for validating the effectiveness of the upscaled soil Hydraulic Parameters. It was found that the power-averaging algorithm produced reasonably good estimates of effective soil Hydraulic Parameters at coarse scales. Further, a probable threshold dimension beyond which the topography dominates the soil Hydraulic property variation was analyzed. On the basis of only the topography, the scaling algorithm was able to capture much of the variation in soil Hydraulic Parameters required to generate equivalent flows and soil moisture states in a coarsened domain.
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A comparative study of multiple approaches to soil Hydraulic Parameter scaling applied at the hillslope scale
Water Resources Research, 2012Co-Authors: Raghavendra B. Jana, Binayak P. MohantyAbstract:[1] Soil Hydraulic Parameters were upscaled from a 30 m resolution to a 1 km resolution using four different aggregation schemes across the Little Washita watershed in Oklahoma. A topography-based aggregation scheme, a simple homogenization method, a Markov chain Monte Carlo (MCMC)-based stochastic technique, and a Bayesian neural network (BNN) approach to the upscaling problem were analyzed in this study. The equivalence of the upscaled Parameters was tested by simulating water flow for the watershed pixels in HYDRUS-3-D, and comparing the resultant soil moisture states with data from the electronically scanned thin array radiometer (ESTAR) airborne sensor during the SGP97 hydrology experiment. The watershed was divided into pixels of 1 km resolution and the effective soil Hydraulic Parameters obtained for each pixel. The domains were then simulated using the physics-based HYDRUS-3-D platform. Simulated soil moisture states were compared across scales, and the coarse scale values compared against the ESTAR soil moisture data products during the SGP97 hydrology experiment period. Results show considerable correlations between simulated and observed soil moisture states across time, topographic variations, location, elevation, and land cover for techniques that incorporate topographic information in their routines. Results show that the inclusion of topography in the Hydraulic Parameter scaling algorithm accounts for much of the variability. The topography-based scaling algorithm, followed by the BNN technique, were able to capture much of the variation in soil Hydraulic Parameters required to generate equivalent soil moisture states in a coarsened domain. The homogenization and MCMC methods, which did not account for topographic variations, performed poorly in providing effective soil Hydraulic Parameters at the coarse scale.
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A topography-based scaling algorithm for soil Hydraulic Parameters at hillslope scales: Field testing
Water Resources Research, 2012Co-Authors: Raghavendra B. Jana, Binayak P. MohantyAbstract:[1] Soil Hydraulic Parameters were upscaled from a 30 m resolution to a 1 km resolution using a new aggregation scheme (described in the companion paper) where the scale Parameter was based on the topography. When soil Hydraulic Parameter aggregation or upscaling schemes ignore the effect of topography, their application becomes limited at hillslope scales and beyond, where topography plays a dominant role in soil deposition and formation. Hence the new upscaling algorithm was tested at the hillslope scale (1 km) across two locations: (1) the Little Washita watershed in Oklahoma, and (2) the Walnut Creek watershed in Iowa. The watersheds were divided into pixels of 1 km resolution and the effective soil Hydraulic Parameters obtained for each pixel. Each pixel/domain was then simulated using the physically based HYDRUS-3-D modeling platform. In order to account for the surface (runoff/on) and subsurface fluxes between pixels, an algorithm to route infiltration-excess runoff onto downstream pixels at daily time steps and to update the soil moisture states of the downstream pixels was applied. Simulated soil moisture states were compared across scales, and the coarse scale values compared against the airborne soil moisture data products obtained during the hydrology experiment field campaign periods (SGP97 and SMEX02) for selected pixels with different topographic complexities, soil distributions, and land cover. Results from these comparisons show good correlations between simulated and observed soil moisture states across time, topographic variations, location, elevation, and land cover. Stream discharge comparisons made at two gauging stations in the Little Washita watershed also provide reasonably good results as to the suitability of the upscaling algorithm used. Based only on the topography of the domain, the new upscaling algorithm was able to provide coarse resolution values for soil Hydraulic Parameters which effectively captured the variations in soil moisture across the watershed domains.
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Upscaling Soil Hydraulic Parameters in the Picacho Mountain Region Using Bayesian Neural Networks
Transactions of the ASABE, 2012Co-Authors: Raghavendra B. Jana, Binayak P. Mohanty, Zhuping ShengAbstract:A multiscale Bayesian neural network (BNN) based algorithm was applied to obtain soil Hydraulic Parameters at multiple scales in the Rio Grande basin (near Picacho Mountain, approximately 11 km northwest of Las Cruces, New Mexico). Point-scale measurements were upscaled to 30 m and 1 km resolutions. These scaled Parameters were used in a physically based hydrologic model as inputs to obtain soil moisture states across the study area. The test sites were chosen to provide variety in terrain, land use characteristics, vegetation, soil types, and soil distribution patterns. In order to validate the effectiveness of the upscaled soil water retention Parameters, and thus the soil Hydraulic Parameters, hydrologic simulations were conducted using the HYDRUS-3D hydrologic simulation software. Outputs from the hydrologic simulations using the scaled Parameters were compared with those using data from SSURGO and STATSGO soil maps. The BNN-based upscaling algorithm for soil retention Parameters from point-scale measurements to 30 m and 1 km, resolutions performed reasonably well (Pearson's R > 0.6) at both scales. High correlations (>0.6) between the simulated soil moisture values based on the upscaled and the soil map-derived soil Hydraulic Parameters show that the methodology is applicable to semi-arid regions to obtain effective soil Hydraulic Parameter values at coarse scales from fine-scale measurements of soil texture, structure, and retention data.
Jianting Zhu - One of the best experts on this subject based on the ideXlab platform.
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Effective Soil Hydraulic Parameters for Transient Flows in Heterogeneous Soils
Vadose Zone Journal, 2009Co-Authors: Jianting Zhu, Dongmin SunAbstract:This study investigated the use of effective soil Hydraulic properties (expressed in terms of Hydraulic Parameters) applicable to large-scale transient infiltration problems in a landscape with horizontally heterogeneous soil Hydraulic properties. The heterogeneous landscape was conceptualized as an equivalent homogeneous medium with effective Hydraulic properties. The main objectives were to investigate: (i) which effective soil Hydraulic property schemes are suitable to represent average behavior of large-scale infiltration processes, (ii) how the effective Hydraulic Parameters are sensitive to the process time frame, and (iii) how Hydraulic Parameter variability and correlation impact the effective Hydraulic Parameters. The heterogeneous landscape was represented by a series of vertically homogeneous stream tubes or parallel columns. Large-scale average infiltration behavior in the heterogeneous soils was quantified through Monte Carlo simulations of multiple realizations (stream tubes) of local-scale infiltration. The optimal effective Hydraulic Parameters were then calculated with an inverse procedure that minimized the difference between average cumulative infiltration and cumulative infiltration based on a single set of effective Parameters. Three scenarios were used to optimize either two Hydraulic Parameters simultaneously or only one Hydraulic Parameter while using the arithmetic mean for the other Parameter. Results indicate that while the effective Hydraulic Parameters could simulate average infiltration more closely when multiple Parameters were optimized together, the effective Parameter values were more variable as time evolved. Optimizing only one Hydraulic Parameter while keeping the arithmetic mean for the other Parameter produced more uniform effective Hydraulic Parameters with time, but this approach did not represent average infiltration behavior of the heterogeneous soils as well as when multiple Hydraulic Parameters were optimized simultaneously.
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Effective Hydraulic Parameters in Horizontally and Vertically Heterogeneous Soils for Steady-State Land-Atmosphere Interaction
Journal of Hydrometeorology, 2007Co-Authors: Binayak P. Mohanty, Jianting ZhuAbstract:In this study, the authors investigate effective soil Hydraulic Parameter averaging schemes for steady-state flow in heterogeneous shallow subsurfaces useful to land–atmosphere interaction modeling. “Effective” soil Hydraulic Parameters of the heterogeneous shallow subsurface are obtained by conceptualizing the soil as an equivalent homogeneous medium. It requires that the effective homogeneous soil discharges the same mean surface moisture flux (evaporation or infiltration) as the heterogeneous media. Using the simple Gardner unsaturated Hydraulic conductivity function, the authors derive the effective value for the saturated Hydraulic conductivity Ks or the shape factor under various hydrologic scenarios and input Hydraulic Parameter statistics. Assuming one-dimensional vertical moisture movement in the shallow unsaturated soils, both scenarios of horizontal (across the surface landscape) and vertical (across the soil profile) heterogeneities are investigated. The effects of Hydraulic Parameter statistics, surface boundary conditions, domain scales, and fractal dimensions in case of nested soil Hydraulic property structure are addressed. Results show that the effective Parameters are dictated more by the heterogeneity for the evaporation scenario and mainly by Ks variability for the infiltration scenario. Also, heterogeneity orientation (horizontal or vertical) of soil Hydraulic Parameters impacts the effective Parameters. In general, an increase in both the fractal dimension and the domain scale enhances the heterogeneous effects of the Parameter fields on the effective Parameters. The impact of the domain scale on the effective Hydraulic Parameters is more significant as the fractal dimension increases.
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Soil Hydraulic Parameter Upscaling for Steady-State Flow with Root Water Uptake
Vadose Zone Journal, 2004Co-Authors: Jianting Zhu, Binayak P. MohantyAbstract:In this study we investigate effective soil Hydraulic Parameter averaging schemes for steady-state flow with plant root water uptake in heterogeneous soils. “Effective” soil Hydraulic Parameters of a heterogeneous soil formation are obtained by conceptualizing the soil as an equivalent homogeneous medium. The “effective” homogeneous medium is only required to discharge the same ensemble-mean flux across the soil surface. One-dimensional flow at the local scale has been used as an approximation for various simplified problems under investigation (e.g., a shallow subsurface dominated by vertical flows). The domain is assumed to be composed of homogeneous one-dimensional soil columns without mutual interactions. Using Gardner9s unsaturated Hydraulic conductivity model, we derive the effective value for the Parameter α. While root water uptake influences the overall water budget, its impact on the effective Hydraulic Parameter averaging scheme was found to be secondary. Results show that the arithmetic mean of Gardner9s α is usually too large to serve as an effective Parameter. Deviations of the effective Parameter from the arithmetic mean become larger as the surface suction increases; that is, the flow scenario switches from infiltration to evaporation. The results consistently show a smaller effective Parameter for evaporation scenarios than for infiltration scenarios. The effective Parameter α eff decreases with an increase in the mean value of α. Spatial variability in α also decreases the effective value of α eff . Alternative root water uptake distributions do not produce significant differences in both the water budget and the averaging scheme as long as total water loss to the plant roots remains the same.
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Spatial Averaging of van Genuchten Hydraulic Parameters for Steady‐State Flow in Heterogeneous Soils: A Numerical Study
Vadose Zone Journal, 2002Co-Authors: Jianting Zhu, Binayak P. MohantyAbstract:For meso- or regional-scale Soil–Vegetation–Atmosphere Transfer (SVAT) schemes in hydroclimatic models, pixel dimensions may range from several hundred square meters to several hundred square kilometers. Pixel-scale soil Hydraulic Parameters and their accuracy are critical for the success of hydroclimatic and soil hydrologic models. This study tries to answer a major question: What will be the effective and average Hydraulic properties for the entire pixel (or footprint of a remote sensor) consisting of several textures if the soil Hydraulic properties can be estimated for each individual texture? In this study, we examined the impact of areal heterogeneity in soil Hydraulic Parameters on soil ensemble behavior for steady-state evaporation and infiltration. Using the widely used van Genuchten model and Hydraulic Parameter statistics obtained from neural network–based pedotransfer functions (PTFs) for various soil textural classes, we address the impact of areal Hydraulic property heterogeneity on ensemble behavior and uncertainty in steady-state vertical flow in large-scale heterogeneous fields. The various averaging schemes of van Genuchten Parameters are compared with “effective Parameters” calculated by conceptualizing the areally heterogeneous soil formation as an equivalent homogeneous medium that will discharge approximately the same amount of ensemble flux of the heterogeneous soil. The impact of boundary conditions and Parameter correlation on the effective Parameters, as well as the accuracy and uncertainty of the averaging schemes for the Hydraulic Parameters, are investigated and discussed. In light of our results, we suggest the following guidelines for van Genuchten Hydraulic Parameter averaging: arithmetic means for Ks and n , a value between arithmetic and geometric means for α when Ks and α are highly correlated, and a value between geometric and harmonic means for α when Ks and α are poorly correlated.
Gilles Boulet - One of the best experts on this subject based on the ideXlab platform.
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An evaporation test based on Thermal Infra Red Remote-Sensing to select appropriate soil Hydraulic properties
Journal of Hydrology, 2009Co-Authors: Gilles Boulet, Bernard Mougenot, Tarik Ben AbdelouahabAbstract:Pedotransfer functions are the most widely used method to estimate common soil Hydraulic properties at regional scale. Since they rely on an empirical link between textural and structural soil properties observed in the laboratory on undisturbed soil samples, one must check whether the pedotransfer functions built elsewhere also apply to the location of interest. Alternative methods to laboratory analysis, such as infiltration tests, exist but are difficult to carry out at large scales. Here we propose a method for selecting appropriate soil Hydraulic properties based on the physical link between the soil water diffusion properties and the plant water stress, which has been named the “evaporation test”. It consists in (i) detecting water stress from remote sensing data in the Thermal Infra Red spectrum and a simulated unstressed surface temperature, then (ii) estimating the date of the last irrigation/rainfall event, the water content at the end of this irrigation/rainfall event, the unstressed evapotranspiration rate and the average root depth and (iii) reducing the range of possible values for the Hydraulic Parameters to those that compute a time-to-stress that is consistent with the observed one, i.e. the difference between the observed water stress date and the date of the end of the last irrigation/rainfall event. The performance of this method is then checked for two sites within the frame of the SudMed and SALSA experiments by comparing the resulting properties to those obtained by other methods, namely the Beerkan infiltration test and the most commonly used pedotransfer functions. While not providing a unique set of Hydraulic properties, the “evaporation test” is a good mean to refine the range of appropriate Hydraulic Parameter values at the scale of the Thermal Infra Red data.
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An evaporation test based on thermal infra red remote-sensing to select appropriate soil Hydraulic properties
Journal of Hydrology, 2009Co-Authors: Gilles Boulet, Bernard Mougenot, Tarik Ben AbdelouahabAbstract:Pedotransfer functions are the most widely used method to estimate common soil Hydraulic properties at regional scale. Since they rely on an empirical link between textural and structural soil properties observed in the laboratory on undisturbed soil samples, one must check whether the pedotransfer functions built elsewhere also apply to the location of interest. Alternative methods to laboratory analysis, such as infiltration tests, exist but are difficult to carry out at large scales. Here we propose a method for selecting the appropriate Hydraulic properties based on the physical link between the soil water diffusion properties and the plant water stress, which has been named the "evaporation test". It consists in (i) detecting water stress from remote-sensing data in the Thermal Infra Red spectrum and a simulated unstressed surface temperature, then (ii) estimating the date of the last irrigation/rainfall event, the water content at the end of this irrigation/rainfall event, the unstressed evapotranspiration rate and the average root depth and (iii) reducing the range of possible values of the Hydraulic Parameters to those that compute a time-to-stress that is consistent with the observed one, i.e. the difference between the observed water stress date and the date of the end of the last irrigation/rainfall event. The performance of this method is then checked for two sites within the frame of the SudMed and SALSA experiments by comparing the resulting properties to those obtained by other methods, namely the Beerkan infiltration test and the most commonly used pedotransfer functions. While not providing a unique set of Hydraulic properties, the "evaporation test" is a good mean to refine the range of appropriate Hydraulic Parameter values at the scale of the Thermal Infra Red data.
Bernard Mougenot - One of the best experts on this subject based on the ideXlab platform.
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An evaporation test based on Thermal Infra Red Remote-Sensing to select appropriate soil Hydraulic properties
Journal of Hydrology, 2009Co-Authors: Gilles Boulet, Bernard Mougenot, Tarik Ben AbdelouahabAbstract:Pedotransfer functions are the most widely used method to estimate common soil Hydraulic properties at regional scale. Since they rely on an empirical link between textural and structural soil properties observed in the laboratory on undisturbed soil samples, one must check whether the pedotransfer functions built elsewhere also apply to the location of interest. Alternative methods to laboratory analysis, such as infiltration tests, exist but are difficult to carry out at large scales. Here we propose a method for selecting appropriate soil Hydraulic properties based on the physical link between the soil water diffusion properties and the plant water stress, which has been named the “evaporation test”. It consists in (i) detecting water stress from remote sensing data in the Thermal Infra Red spectrum and a simulated unstressed surface temperature, then (ii) estimating the date of the last irrigation/rainfall event, the water content at the end of this irrigation/rainfall event, the unstressed evapotranspiration rate and the average root depth and (iii) reducing the range of possible values for the Hydraulic Parameters to those that compute a time-to-stress that is consistent with the observed one, i.e. the difference between the observed water stress date and the date of the end of the last irrigation/rainfall event. The performance of this method is then checked for two sites within the frame of the SudMed and SALSA experiments by comparing the resulting properties to those obtained by other methods, namely the Beerkan infiltration test and the most commonly used pedotransfer functions. While not providing a unique set of Hydraulic properties, the “evaporation test” is a good mean to refine the range of appropriate Hydraulic Parameter values at the scale of the Thermal Infra Red data.
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An evaporation test based on thermal infra red remote-sensing to select appropriate soil Hydraulic properties
Journal of Hydrology, 2009Co-Authors: Gilles Boulet, Bernard Mougenot, Tarik Ben AbdelouahabAbstract:Pedotransfer functions are the most widely used method to estimate common soil Hydraulic properties at regional scale. Since they rely on an empirical link between textural and structural soil properties observed in the laboratory on undisturbed soil samples, one must check whether the pedotransfer functions built elsewhere also apply to the location of interest. Alternative methods to laboratory analysis, such as infiltration tests, exist but are difficult to carry out at large scales. Here we propose a method for selecting the appropriate Hydraulic properties based on the physical link between the soil water diffusion properties and the plant water stress, which has been named the "evaporation test". It consists in (i) detecting water stress from remote-sensing data in the Thermal Infra Red spectrum and a simulated unstressed surface temperature, then (ii) estimating the date of the last irrigation/rainfall event, the water content at the end of this irrigation/rainfall event, the unstressed evapotranspiration rate and the average root depth and (iii) reducing the range of possible values of the Hydraulic Parameters to those that compute a time-to-stress that is consistent with the observed one, i.e. the difference between the observed water stress date and the date of the end of the last irrigation/rainfall event. The performance of this method is then checked for two sites within the frame of the SudMed and SALSA experiments by comparing the resulting properties to those obtained by other methods, namely the Beerkan infiltration test and the most commonly used pedotransfer functions. While not providing a unique set of Hydraulic properties, the "evaporation test" is a good mean to refine the range of appropriate Hydraulic Parameter values at the scale of the Thermal Infra Red data.
