Assessment of Soil Water Thermodynamic to Unify Water Retention Curve by Pressure Plates and Tensiometer| Chapter 5 | Novel Perspectives of Geography, Environment and Earth Sciences Vol. 3

 In soil skill, skilled are two famous standard procedures for weighing the soil liquid characteristic curve: the pressure plate plan providing the pF curve and the tensiometer providing the soil assimilation pressure curve. These two practical curves are mainly used for typifing and posing the soil water characteristics. The two approaches are established two very various calculation ideas, and material unity of the calculated variables has never existed illustrated. The currently thermodynamic expression of the pedostructure water memory curve h(W) admits us examining this unity, two together in theory and experimentally. This authorizes the object of the item. We establish that the pressure plate arrangement supports correct calculation points of the water memory curve of the pedostructure h(W) but on the condition that h is not deliberate usually, as prepared the air pressure used to the sample. Instead, in accordance with the thermodynamic belief grown attending, h must be determined as the mathematical of the air pressure used to the pedostructure sample to correspond to the assimilation pressure straightforwardly calculated for one tensiometer. We therefore show by virtue of what the hydrostructural limits of the hypothetical curve equating maybe supposed from some calculated curve, however calculation method. An use instance utilizing published pF curves is likely.

Author(s) Details:

Erik Braudeau,
Qatar Environment and Energy Research Institute, Qatar Foundation, Doha, Qatar and Pédologie Hydrostructurale, Institut de Recherche pour le Développement France Nord, Institut de Recherche Pour le Développement, Bondy, France.

Gaghik Hovhannissian,
Unité Mixte de Recherche 242, Institut d'Ecologie et des Sciences de l'Environnement de Paris, Institut de Recherche pour le Développement France Nord, Institut de Recherche Pour le Développement, Bondy, France.

Amjad T. Assi,
Qatar Environment and Energy Research Institute, Qatar Foundation, Doha, Qatar and Biological and Agricultural Engineering Department, Texas A&M University, College Station, TX, USA.

Rabi H. Mohtar,
Biological and Agricultural Engineering and Zachry Departments of Civil Engineering, Texas A&M University, College Station, TX, USA.

Please see the link here: https://stm.bookpi.org/NPGEES-V3/article/view/9375

Thermodynamic Formulation of the Pedostructure Water Retention and Shrinkage Curves: An Approach to Soil Medium Organization| Chapter 4 | Novel Perspectives of Geography, Environment and Earth Sciences Vol. 3

 The two characteristic soil moisture curves: the soil water retention curve and the shrinkage curve, necessary for the physical modeling of the hydrological and agronomic properties of the soil are, still today, entirely empirical. They have been established so far without referring to the hydrostructural and thermodynamic properties of the pedostructure, nor to the internal and hierarchical organization of the soil pedon and its horizons which are described in Hydrostructural Pedology. On the contrary, this article presents the development of these equations according to the systemic and thermodynamic paradigm of this new scientific discipline of earth sciences.  We show how the aqueous phase of the pedostructure is divided into two types of water positioned differently in the pedostructure: one in the plasma porosity of the primary aggregates and the other outside the primary aggregates in the inter-aggregate porosity. The thermodynamic equilibrium established between these two types of water has been put into equations to represent the pedostructural water retention curve h(W) resulting from this equilibrium: the suction pressure of the pedostructure as a function of the water content. Using information from simultaneous measurements of both curves, the new equations were put to the test and the theory was verified.  The implications of these findings for physical modelling in agro-environmental sciences are discussed.

Author(s) Details:

Erik Braudeau,
Qatar Foundation, Qatar Environment and Energy Research Institute, Doha, Qatar and Institut de Recherche pour le Développement, Bondy, France.

Amjad T. Assi,
Qatar Foundation, Qatar Environment and Energy Research Institute, Doha, Qatar and Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, USA.

Hassan Boukcim,
Valorhiz SAS, Parc Scientifique Agropolis II Bat 6, Montferrier-sur-Lez, France.

Rabi H. Mohtar,
Biological and Agricultural Engineering Department, and Zachry Department of Civil Engineering, Texas A&M University, College Station, TX, USA.

Please see the link here: https://stm.bookpi.org/NPGEES-V3/article/view/9374

Evaluation of Hydraulic Conductivity and Diffusion Coefficient of Unsaturated Soils from Experimental SWRC| Chapter 2 | Current Overview on Science and Technology Research Vol. 10

 Fine unsaturated soils change their water content on account of climatic environments, pipe failure, and other determinants. These changes produce drying-wetting phases that generate decrease-swelling cycles on account of variations in soil influence and water content. Several theoretical models are used to estimate the hydraulic act of soils (hydraulic conductivity and diffusion cooperative) by fitting the SWRC. The fitting model precision depends mostly on the accuracy of the exploratory points of the SWRC and the fitting model. Because of this, it is advisable to simply use the exploratory data from the SWRC to acquire the hydraulic behavior. Therefore, an treasure based on a data table, that uses an interpolation form with variable enlargements, is proposed. The process approximates the experimental SWRC utilizing a polynomial equation generated each branch (drying and moisting). This procedure clarifies the indirect method and avoids wrongs caused for one SWRC fitting process because it does not demand fitting parameters. The results show that the hydraulic behavior of soils maybe predicted exactly with the projected method than with the usual methods.

Author(s) Details:

J. R. Galaviz-González,
Department of Civil Engineering and Topography, University of Guadalajara, 1421 Blvd. Marcelino García Barragán, Guadalajara-44430, Mexico.

J. M. Horta-Rangel,
Graduate Engineering Department, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Queretaro, Qro. C.P.-76010, Mexico.

E. Rojas-Gonzalez,
Graduate Engineering Department, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Queretaro, Qro. C.P.-76010, Mexico.

M. L. Pérez-Rea,
Graduate Engineering Department, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Queretaro, Qro. C.P.-76010, Mexico.

T. Lopez-Lara,
Graduate Engineering Department, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Queretaro, Qro. C.P.-76010, Mexico.

J. B. Hernandez-Zaragoza,
Graduate Engineering Department, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Queretaro, Qro. C.P.-76010, Mexico.

L. Y. Cabello-Suárez,
Department of Project Engineering, University of Guadalajara, 48 Blvd. José Guadalupe Zuno, Zapopan-45157, Mexico.

Please see the link here: https://stm.bookpi.org/COSTR-V10/article/view/8902