The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Erik Braudeau - One of the best experts on this subject based on the ideXlab platform.
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Soil aggregates structure-based approach for quantifying the field capacity, Permanent Wilting Point and available water capacity
Irrigation Science, 2019Co-Authors: Amjad T. Assi, Rabi H. Mohtar, John Blake, Erik BraudeauAbstract:Soil plays a pivotal role in enhancing global water and food security. Irrigation water constitutes more than 70% of the global water demand. The anticipated demographic increase and changing climate will impose more pressures on the global water and food systems. Therefore, and to achieve the target of “more crop per drop per area”, water management plans must be based on more accurate quantitative and dynamic approaches. It is increasingly obvious that the unique aggregates structure of the soil medium regulates water and nutrient circulations, and consequently defines soil and water health, productivity, and water use efficiency. However, the soil aggregates structure is not currently well considered in the quantification of soil–water holding properties. The authors applied a thermodynamic and soil structure-based approach to quantify soil–water holding properties. Specifically, the paper aims at providing a methodology, based on the pedostructure concept, to quantify field capacity (FC), Permanent Wilting Point (PWP), and plant available water (AW). Pedostructure is a representative aggregates unit of a soil horizon that describes the structural organization of the soil medium. Four types of soil were analyzed considering various soil texture and aggregates structure: loamy fine sand, silt loam, clay loam, and silty clay loam. The calculated values for FC and PWP, based on the proposed pedostructure method, were compared with the recommended values by the standard FAO method and soil suction method. Results showed good agreement between the calculated values of the two methods. The proposed pedostructure method introduces a shift in quantifying the plant available water from a texture-based estimation to a soil aggregates structure-based calculation. Such a shift will enable capturing the changes in soil aggregates structure due to agro-environmental practices and the associated impact of these changes on soil–water holding properties.
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Soil pedostructure-based method for calculating the soil-water holding properties.
MethodsX, 2018Co-Authors: Amjad T. Assi, Rabi H. Mohtar, Erik BraudeauAbstract:Abstract Soil aggregates structure (pedostructure) plays a pivotal role in regulating water and nutrient circulation, and consequently defines soil health, productivity, and water use efficiency. However, the soil aggregates structure is not currently considered in the quantification of soil-water holding properties. The authors applied a thermodynamic and soil structure-based approach to quantify soil-water holding properties. The paper provides a methodology, based on pedostructure concept, to quantify field capacity (FC), Permanent Wilting Point (PWP), and available water (AW). The validity of the developed method was tested through application to two types of soil: a loamy fine sand soil and a silt loam soil. The calculated values for FC, PWP, and AW were compared with the FAO recommended values of FC, PWP and AW. For the loamy fine sand, the calculated values were: FC = 0.208 m3/m3, PWP = 0.068 m3/m3, and AW = 0.140 m3/m3 all of which fall within the recommended values of FAO for such a soil type. Similarly, the calculated values for the silt loam were: FC = 0.283 m3/m3, PWP = 0.184 m3/m3, and AW = 0.071 m3/m3 all were in agreement with the FAO recommended ranges for such a soil type. • A thermodynamic, structure-based approach for soil water holding properties. • Unique solutions for quantifying both field capacity and Permanent Wilting Point.
Mingan Shao - One of the best experts on this subject based on the ideXlab platform.
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Estimating the field capacity and Permanent Wilting Point at the regional scale for the Hexi Corridor in China using a state-space modeling approach
Journal of Soils and Sediments, 2019Co-Authors: Mingan Shao, Chunlei ZhaoAbstract:PURPOSE: The field capacity (FC) and Permanent Wilting Point (PWP) are important soil hydraulic properties that determine the maximum available water for plants, and they are crucial parameters for biophysical models and irrigation management. However, previous estimates of the FC and PWP failed to consider their spatial correlations at the regional scale. Therefore, we estimated the FC and PWP using the state-space equation by considering the spatial correlations between soil properties. MATERIALS AND METHODS: We estimated the FC and PWP using a first order autoregressive state-space equation based on the elevation (Elev), bulk density (BD), soil texture (Clay, Silt, Sand), soil organic carbon (SOC), and land use (LU) with a data set obtained from 104 in situ sampling sites across the entire Hexi Corridor. RESULTS AND DISCUSSION: The results indicated that the distributions of the FC and PWP exhibited moderate variations in the Hexi Corridor, with values of 0.127 ± 0.060 and 0.075 ± 0.034 g/g (mean ± 1 standard deviation (SD)), respectively. According to t tests, the autocorrelation coefficients for FC, PWP, Elev, LU, Silt, Sand, and SOC as well as the cross-correlation coefficients between FC, PWP, and pertinent variables were significant with one lag distance (approximately 40 km) (p ˂ 0.05). Calculations of the coefficient of determination (R²) and root mean square error (RMSE) showed that the state-space models performed better at estimating FC and PWP than multiple linear stepwise regression models (SMLRs). Bivariate state-space equations based on Silt and LU were the optimal models for estimating FC (R² = 0.999, RMSE = 0.002 g/g) and PWP (R² = 0.997, RMSE = 0.002 g/g). According to the coefficients in the optimal state-space models, soil texture and LU were the dominant factors that affected the spatial variability in FC and PWP. After neglecting the spatial correlations between variables, the SMLRs showed that BD and soil texture were the best variables for estimating FC and PWP. CONCLUSIONS: The state-space approach is recommended as a useful tool for quantifying larger-scale spatial patterns in soil properties.
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pedotransfer functions for estimating the field capacity and Permanent Wilting Point in the critical zone of the loess plateau china
Journal of Soils and Sediments, 2019Co-Authors: Jiangbo Qiao, Laiming Huang, Mingan ShaoAbstract:Field capacity (FC) and Permanent Wilting Point (PWP) are important physical properties for evaluating the available soil water storage, as well as being used as input variables for related agro-hydrological models. Direct measurements of FC and PWP are time consuming and expensive, and thus, it is necessary to develop related pedotransfer functions (PTFs). In this study, stepwise multiple linear regression (SMLR) and artificial neural network (ANN) methods were used to develop FC and PWP PTFs for the deep layer of the Loess Plateau based on the bulk density (BD),sand, silt, clay, and soil organic carbon (SOC) contents. Soil core drilling was used to obtain undisturbed soil cores from three typical sites on the Loess Plateau, which ranged from the top of the soil profile to the bedrock (0–200 m). The FC and PWP were measured using the centrifugation method at suctions of − 33 and − 1500 kPa, respectively. The results showed that FC and PWP exhibited moderate variation where the coefficients of variation were 11 and 23%, respectively. FC had significant correlations with sand, silt, clay, and SOC (P < 0.01), while there were also significant correlations between all of the variables and PWP. In addition, sand was an important input variable for predicting FC, and clay and BD for predicting PWP. The performance of the SMLR and ANN approaches was similar. In this study, we developed new PTFs for FC and PWP as the first set of PTFs based on data obtained from deep profiles in the Loess Plateau. These PTFs are important for evaluating the soil water conditions in the deep profile in this region.
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Pedotransfer functions for estimating the field capacity and Permanent Wilting Point in the critical zone of the Loess Plateau, China
Journal of Soils and Sediments, 2018Co-Authors: Jiangbo Qiao, Laiming Huang, Mingan ShaoAbstract:Purpose Field capacity (FC) and Permanent Wilting Point (PWP) are important physical properties for evaluating the available soil water storage, as well as being used as input variables for related agro-hydrological models. Direct measurements of FC and PWP are time consuming and expensive, and thus, it is necessary to develop related pedotransfer functions (PTFs). In this study, stepwise multiple linear regression (SMLR) and artificial neural network (ANN) methods were used to develop FC and PWP PTFs for the deep layer of the Loess Plateau based on the bulk density (BD),sand, silt, clay, and soil organic carbon (SOC) contents.
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Pedotransfer functions for estimating the field capacity and Permanent Wilting Point in the critical zone of the Loess Plateau, China
Journal of Soils and Sediments, 2018Co-Authors: Jiangbo Qiao, Laiming Huang, Yuanjun Zhu, Xiaoxu Jia, Mingan ShaoAbstract:Field capacity (FC) and Permanent Wilting Point (PWP) are important physical properties for evaluating the available soil water storage, as well as being used as input variables for related agro-hydrological models. Direct measurements of FC and PWP are time consuming and expensive, and thus, it is necessary to develop related pedotransfer functions (PTFs). In this study, stepwise multiple linear regression (SMLR) and artificial neural network (ANN) methods were used to develop FC and PWP PTFs for the deep layer of the Loess Plateau based on the bulk density (BD),sand, silt, clay, and soil organic carbon (SOC) contents. Soil core drilling was used to obtain undisturbed soil cores from three typical sites on the Loess Plateau, which ranged from the top of the soil profile to the bedrock (0–200 m). The FC and PWP were measured using the centrifugation method at suctions of − 33 and − 1500 kPa, respectively. The results showed that FC and PWP exhibited moderate variation where the coefficients of variation were 11 and 23%, respectively. FC had significant correlations with sand, silt, clay, and SOC (P
Amjad T. Assi - One of the best experts on this subject based on the ideXlab platform.
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Soil aggregates structure-based approach for quantifying the field capacity, Permanent Wilting Point and available water capacity
Irrigation Science, 2019Co-Authors: Amjad T. Assi, Rabi H. Mohtar, John Blake, Erik BraudeauAbstract:Soil plays a pivotal role in enhancing global water and food security. Irrigation water constitutes more than 70% of the global water demand. The anticipated demographic increase and changing climate will impose more pressures on the global water and food systems. Therefore, and to achieve the target of “more crop per drop per area”, water management plans must be based on more accurate quantitative and dynamic approaches. It is increasingly obvious that the unique aggregates structure of the soil medium regulates water and nutrient circulations, and consequently defines soil and water health, productivity, and water use efficiency. However, the soil aggregates structure is not currently well considered in the quantification of soil–water holding properties. The authors applied a thermodynamic and soil structure-based approach to quantify soil–water holding properties. Specifically, the paper aims at providing a methodology, based on the pedostructure concept, to quantify field capacity (FC), Permanent Wilting Point (PWP), and plant available water (AW). Pedostructure is a representative aggregates unit of a soil horizon that describes the structural organization of the soil medium. Four types of soil were analyzed considering various soil texture and aggregates structure: loamy fine sand, silt loam, clay loam, and silty clay loam. The calculated values for FC and PWP, based on the proposed pedostructure method, were compared with the recommended values by the standard FAO method and soil suction method. Results showed good agreement between the calculated values of the two methods. The proposed pedostructure method introduces a shift in quantifying the plant available water from a texture-based estimation to a soil aggregates structure-based calculation. Such a shift will enable capturing the changes in soil aggregates structure due to agro-environmental practices and the associated impact of these changes on soil–water holding properties.
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Soil pedostructure-based method for calculating the soil-water holding properties.
MethodsX, 2018Co-Authors: Amjad T. Assi, Rabi H. Mohtar, Erik BraudeauAbstract:Abstract Soil aggregates structure (pedostructure) plays a pivotal role in regulating water and nutrient circulation, and consequently defines soil health, productivity, and water use efficiency. However, the soil aggregates structure is not currently considered in the quantification of soil-water holding properties. The authors applied a thermodynamic and soil structure-based approach to quantify soil-water holding properties. The paper provides a methodology, based on pedostructure concept, to quantify field capacity (FC), Permanent Wilting Point (PWP), and available water (AW). The validity of the developed method was tested through application to two types of soil: a loamy fine sand soil and a silt loam soil. The calculated values for FC, PWP, and AW were compared with the FAO recommended values of FC, PWP and AW. For the loamy fine sand, the calculated values were: FC = 0.208 m3/m3, PWP = 0.068 m3/m3, and AW = 0.140 m3/m3 all of which fall within the recommended values of FAO for such a soil type. Similarly, the calculated values for the silt loam were: FC = 0.283 m3/m3, PWP = 0.184 m3/m3, and AW = 0.071 m3/m3 all were in agreement with the FAO recommended ranges for such a soil type. • A thermodynamic, structure-based approach for soil water holding properties. • Unique solutions for quantifying both field capacity and Permanent Wilting Point.
Lorena Chagas Torres - One of the best experts on this subject based on the ideXlab platform.
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Impacts of soil type and crop species on Permanent Wilting of plants
Geoderma, 2021Co-Authors: Lorena Chagas Torres, Cássio Antonio Tormena, Thomas Keller, Renato P. De Lima, Herdjania Veras De Lima, Neyde Fabíola Balazero GiarolaAbstract:Abstract The lack of a continuous network of water-filled pores necessary for the flow of water in the soil has been related to the Wilting of plants as well as to the limitations of soil sample equilibrium in pressure plates. The objectives of this study were: (i) to quantify deviations of the soil water content measured in pressure plates and dew Point measurements at a matric potential of −15,000 hPa (commonly defined as the Permanent Wilting Point), (ii) to determine the soil matric potential at which the physiological Wilting of different plant species occurs in soil with contrasting texture, and (iii) to evaluate if the Wilting of plants occurs at the hydraulic cut-off in soil. An experiment was conducted to determine the soil matric potential at which Wilting of sunflower (Helianthus annuus L.), maize (Zea mays L.) and soybean (Glycine max L.) occurs in four soils with clay contents ranging from 7 to 57%. Soil water retention characteristics were determined by the pressure chamber and the dew Point technique. Soil water retention data were fitted to empirical models for estimates of soil matric potential and water content at the hydraulic cut-off. The water contents at −15,000 hPa in samples equilibrated in pressure plates was similar to those obtained from the dew Point method in our soils. Our results show that physiological Wilting of plants is both plant species and soil dependent. In soils with low clay contents, different plant species wilted at similar water contents. However, in the clayey soils, the different crops showed different abilities in the uptake of water from the soil, where soybean wilted at significantly lower water contents than the other two species. The values of matric potential at the Permanent Wilting Point found in our study were considerably lower than −15,000 hPa, suggesting that the commonly used definition of Permanent Wilting Point as water content at −15,000 hPa is incorrect.
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comparing the classical Permanent Wilting Point concept of soil 15 000 hpa to biological Wilting of wheat and barley plants under contrasting soil textures
Agricultural Water Management, 2020Co-Authors: Lucia H. Wiecheteck, Neyde Fabíola Balarezo Giarola, Renato P. De Lima, Cássio Antonio Tormena, Lorena Chagas Torres, Ariane Lentice De PaulaAbstract:Abstract Recent studies have shown that the Permanent Wilting Point is influenced by soil properties and plant drought-tolerance mechanisms. This study was designed to evaluate the soil matric potential at which the biological Wilting Point (BWPplant) of wheat and barley cultivars occurs compared to the classic concept of the Permanent Wilting Point at a matric potential of -15,000 hPa for soils (PWPsoil) with contrasting textures. The study was performed under greenhouse conditions with the experiment arranged in a completely randomised design in a double factorial scheme with three soil textures (sandy loam - SL, sandy clay loam - SCL and clay - C) and four plants (two crops (wheat and barley) and two cultivars for each crop). The 95 % confidence intervals were used to compare treatment means. The results revealed that BWPplant could occur at matric potential values > −15,000 hPa, i.e. wetter conditions than for the classical PWPsoil. Plants cultivated in clay soils withered at lower matric potentials than those in sandy soils, which could be related to a hydraulic cut-off that occurs at higher matric potentials in sandy soils. Barley plants were more sensitive to water deficits than wheat plants. The BWPplant for barley plants could occur at matric potentials values > −15,000 hPa, independently of soil texture, whereas wheat plants wilted at matric potentials > −15,000 hPa only in sandy soils (e.g. −1,637 to −2,417 hPa). Our results suggest that Wilting depends on soil texture, with an occurrence of Wilting at higher matric potentials (i.e. at wetter soil conditions) for sandy soils than for clay soils. Furthermore, plants/cultivars exhibit various tolerance mechanisms to drought, and wheat is able to take up water at considerably lower matric potentials (at dryer soil conditions) than barley. Thus, the Wilting matric potential threshold across various species and cultivars is not uniform.
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Comparing the classical Permanent Wilting Point concept of soil (−15,000 hPa) to biological Wilting of wheat and barley plants under contrasting soil textures
Agricultural Water Management, 2020Co-Authors: Lucia H. Wiecheteck, Neyde Fabíola Balarezo Giarola, Renato P. De Lima, Cássio Antonio Tormena, Lorena Chagas Torres, Ariane Lentice De PaulaAbstract:Abstract Recent studies have shown that the Permanent Wilting Point is influenced by soil properties and plant drought-tolerance mechanisms. This study was designed to evaluate the soil matric potential at which the biological Wilting Point (BWPplant) of wheat and barley cultivars occurs compared to the classic concept of the Permanent Wilting Point at a matric potential of -15,000 hPa for soils (PWPsoil) with contrasting textures. The study was performed under greenhouse conditions with the experiment arranged in a completely randomised design in a double factorial scheme with three soil textures (sandy loam - SL, sandy clay loam - SCL and clay - C) and four plants (two crops (wheat and barley) and two cultivars for each crop). The 95 % confidence intervals were used to compare treatment means. The results revealed that BWPplant could occur at matric potential values > −15,000 hPa, i.e. wetter conditions than for the classical PWPsoil. Plants cultivated in clay soils withered at lower matric potentials than those in sandy soils, which could be related to a hydraulic cut-off that occurs at higher matric potentials in sandy soils. Barley plants were more sensitive to water deficits than wheat plants. The BWPplant for barley plants could occur at matric potentials values > −15,000 hPa, independently of soil texture, whereas wheat plants wilted at matric potentials > −15,000 hPa only in sandy soils (e.g. −1,637 to −2,417 hPa). Our results suggest that Wilting depends on soil texture, with an occurrence of Wilting at higher matric potentials (i.e. at wetter soil conditions) for sandy soils than for clay soils. Furthermore, plants/cultivars exhibit various tolerance mechanisms to drought, and wheat is able to take up water at considerably lower matric potentials (at dryer soil conditions) than barley. Thus, the Wilting matric potential threshold across various species and cultivars is not uniform.
Ariane Lentice De Paula - One of the best experts on this subject based on the ideXlab platform.
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comparing the classical Permanent Wilting Point concept of soil 15 000 hpa to biological Wilting of wheat and barley plants under contrasting soil textures
Agricultural Water Management, 2020Co-Authors: Lucia H. Wiecheteck, Neyde Fabíola Balarezo Giarola, Renato P. De Lima, Cássio Antonio Tormena, Lorena Chagas Torres, Ariane Lentice De PaulaAbstract:Abstract Recent studies have shown that the Permanent Wilting Point is influenced by soil properties and plant drought-tolerance mechanisms. This study was designed to evaluate the soil matric potential at which the biological Wilting Point (BWPplant) of wheat and barley cultivars occurs compared to the classic concept of the Permanent Wilting Point at a matric potential of -15,000 hPa for soils (PWPsoil) with contrasting textures. The study was performed under greenhouse conditions with the experiment arranged in a completely randomised design in a double factorial scheme with three soil textures (sandy loam - SL, sandy clay loam - SCL and clay - C) and four plants (two crops (wheat and barley) and two cultivars for each crop). The 95 % confidence intervals were used to compare treatment means. The results revealed that BWPplant could occur at matric potential values > −15,000 hPa, i.e. wetter conditions than for the classical PWPsoil. Plants cultivated in clay soils withered at lower matric potentials than those in sandy soils, which could be related to a hydraulic cut-off that occurs at higher matric potentials in sandy soils. Barley plants were more sensitive to water deficits than wheat plants. The BWPplant for barley plants could occur at matric potentials values > −15,000 hPa, independently of soil texture, whereas wheat plants wilted at matric potentials > −15,000 hPa only in sandy soils (e.g. −1,637 to −2,417 hPa). Our results suggest that Wilting depends on soil texture, with an occurrence of Wilting at higher matric potentials (i.e. at wetter soil conditions) for sandy soils than for clay soils. Furthermore, plants/cultivars exhibit various tolerance mechanisms to drought, and wheat is able to take up water at considerably lower matric potentials (at dryer soil conditions) than barley. Thus, the Wilting matric potential threshold across various species and cultivars is not uniform.
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Comparing the classical Permanent Wilting Point concept of soil (−15,000 hPa) to biological Wilting of wheat and barley plants under contrasting soil textures
Agricultural Water Management, 2020Co-Authors: Lucia H. Wiecheteck, Neyde Fabíola Balarezo Giarola, Renato P. De Lima, Cássio Antonio Tormena, Lorena Chagas Torres, Ariane Lentice De PaulaAbstract:Abstract Recent studies have shown that the Permanent Wilting Point is influenced by soil properties and plant drought-tolerance mechanisms. This study was designed to evaluate the soil matric potential at which the biological Wilting Point (BWPplant) of wheat and barley cultivars occurs compared to the classic concept of the Permanent Wilting Point at a matric potential of -15,000 hPa for soils (PWPsoil) with contrasting textures. The study was performed under greenhouse conditions with the experiment arranged in a completely randomised design in a double factorial scheme with three soil textures (sandy loam - SL, sandy clay loam - SCL and clay - C) and four plants (two crops (wheat and barley) and two cultivars for each crop). The 95 % confidence intervals were used to compare treatment means. The results revealed that BWPplant could occur at matric potential values > −15,000 hPa, i.e. wetter conditions than for the classical PWPsoil. Plants cultivated in clay soils withered at lower matric potentials than those in sandy soils, which could be related to a hydraulic cut-off that occurs at higher matric potentials in sandy soils. Barley plants were more sensitive to water deficits than wheat plants. The BWPplant for barley plants could occur at matric potentials values > −15,000 hPa, independently of soil texture, whereas wheat plants wilted at matric potentials > −15,000 hPa only in sandy soils (e.g. −1,637 to −2,417 hPa). Our results suggest that Wilting depends on soil texture, with an occurrence of Wilting at higher matric potentials (i.e. at wetter soil conditions) for sandy soils than for clay soils. Furthermore, plants/cultivars exhibit various tolerance mechanisms to drought, and wheat is able to take up water at considerably lower matric potentials (at dryer soil conditions) than barley. Thus, the Wilting matric potential threshold across various species and cultivars is not uniform.