Download or read book Effect of Soil ESP and Salinity on Soil Atterberg Limits Swelling and Hydrologic Properties written by Hans Walter Klopp and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil sodicity is a global issue decreasing economic outputs of soils. High solution sodium adsorption ratio (SAR) and low EC increases swelling of smectite clay and causes breakdown of soil aggregates. The effect of solution composition on soils has been commonly measured by saturated hydraulic conductivity which decreases as solution EC decreases and SAR increases with the effects most pronounced on smectite clay dominant soils, which also is the only clay type that has interlayer swelling from exchangeable sodium. Currently soil physical properties are not used to classify soils that are sensitive to soil sodicity. The objectives of this dissertation, are 1) to determine how properties related to soil swelling and hydrology change on soils of a range of clay mineralogy, 2) determine a soil physical property that can discriminate between soils that are sensitive to high ESP levels from soils that are not sensitive to soil sodicity and 3) to predict the change of soil properties in response to solution EC and SAR. Soil Atterberg limits, shrinkage and water retention were measured under soil ESP and EC combinations on soils of a range of textures and clay mineralogy, using a dry sodium carbonate treatment and mixtures of sodium and calcium chloride solutions. Soil saturated hydraulic conductivity decreased, and shrinkage, water retention and Atterberg limits increased in smectitic soils. Smectitic soils had a larger change in soil hydraulic conductivity and are the only soils that had pronounced changes in soil physical properties related to swelling from high ESP and low EC. Measuring soil liquid limit or water retention at points of -1/10 or -1/3 bar in a low EC-low ESP and a low EC-high ESP state can distinguish soils sensitive to sodicity from soils not sensitive to sodicity. Existing models to predict soil hydrologic properties performed poorly on smectitic soils. Accounting for the smectite content by cation exchange capacity improved prediction of soil hydrologic properties on smectitic soils. Soils that are smectitic can be rapidly identified by measuring soil swelling related property and have a narrower range of irrigation water qualities acceptable for use before soil hydrologic properties change.
Download or read book Effects of Salinity Sodicity and Clay Mineralogy on the Soil Physical and Hydraulic Properties written by Victor Manuel Ruiz Vera and published by . This book was released on 2005 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Salinity and Water Quality written by R. Chhabra and published by CRC Press. This book was released on 1996-01-01 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume covers such areas in the field of soil salinity and water quality as: origin and distribution of salt-affected soils; management of alkali soils; quality criteria of irrigation water; wastewaters as a source of irrigation; and grasses and trees in the management of salt-affected soils.
Download or read book Saline and Sodic Soils written by E. Bresler and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: In keeping with the spirit of an Advanced Series in the Agricultural Sciences, we have attempted to address herein most of the current research areas being used to characterize, describe and manage salt-affected soils. Because of a certain amount of personal bias inherent in our individual viewpoints and backgrounds, some areas have been accorded more emphasis than others. It has been our goal, however, to provide either detail about, or at least a recent reference to, each major area of current soil salinity research. This information, coupled with what we hope to be a rather logical progression from descriptive material on equilibrium or near-equilibrium soil chemistry, through transport processes, to eventual management practices including some elementary economic decisions, should enable the reader to bridge the gap from introductory soil chemistry or soil physics texts to the basic literature of this area. The text will be perceived by the astute reader as somewhat uneven in its treatment of respective sections. We feel that this is to a certain extent appropriate, for it thus portrays the unevenness of progress to date in the corresponding areas of research. The management of saline and sodic soils remains largely an empirical semi-science or even art, whereas transport phenomena are normally dealt with in a much more theoretical (and also a much more highly mathematical) vein. Equilibrium soil chemistry has historically occupied an intermediate position with respect to its mix of empiricism and theoretical rigor.
Download or read book Developments in Soil Salinity Assessment and Reclamation written by Shabbir A. Shahid and published by Springer Science & Business Media. This book was released on 2013-01-15 with total page 827 pages. Available in PDF, EPUB and Kindle. Book excerpt: The papers assembled here cover topics such as technological advances in soil salinity mapping and monitoring, management and reclamation of salt-affected soils, use of marginal quality water for crop production, salt-tolerance mechanisms in plants, biosaline agriculture and agroforestry, microbiological interventions for marginal soils, opportunities and challenges in using marginal waters, and soil and water management in irrigated agriculture.
Download or read book Salt Effects on the Hydraulic Properties of a Swelling Soil written by J. H. Dane and published by . This book was released on 1977 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modelling the Change in Conductivity of Soil Associated with the Application of Saline sodic Water written by Younes Daw Ezlit and published by . This book was released on 2009 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scarcity of fresh water has led to use of low quality waters (high sodicity and salinity) that were considered unsuitable for irrigation in the past. Mismanagement of irrigation using this water can increase the potential for soil degradation and limit crop production in the long term. Irrigation using highly saline-sodic water requires appropriate management to avoid long term development of sodicity and salinity problems. The main factors that control the sodicity and salinity problems are maintenance of sufficient leaching and avoidance of soil structure degradation due to sodicity. The management options are determined by complex factors such as soil type and condition, water quality, irrigation practice and crop type. Investigating the management options for using highly saline-sodic water in irrigation experimentally is costly and time consuming. However, it could be done using an appropriate modelling tool that can handle the degradation of soil structure due to sodicity along with the chemical reaction system within the soil profile. UNSATCHEM has been widely used to model sodicity and salinity effects under irrigation. It has a feature to deal with soil structure degradation along with water and solute movement, major ion chemistry, CO2 production and movement and heat transfer under sodic conditions. It uses a hydraulic conductivity reduction function to relate the change of chemical properties to the change in hydraulic properties of the soil. However, the evaluation of the hydraulic conductivity reduction function under high sodicity during simulation has not been done. Hence, the core of this research project has been to improve quantification of soil structure degradation under sodic conditions and enhance the modelling of water and solute movement under sodic conditions. The hydraulic conductivity reduction function incorporated in UNSATCHEM was evaluated using data obtained from soil column experiments. Columns of two local soils were used in an experiment to investigate the effect on soil structural stability of different amendments to highly saline-sodic water rich with bicarbonates (EC = 4.6 dS/m and SAR = 117). The column experiments were used to examine the effect of reducing water pH to different levels using sulphuric acid and combined gypsum and dilution treatments. It was found that reducing the pH of highly saline-sodic water did not enhance soil structural stability as the water applied has naturally high relative sodium concentrations. However, the application of diluted highly saline-sodic water amended with gypsum showed no significant effect on soil structure and permeability. It is concluded that different amendments associated with appropriate irrigation management can be applied to sustain irrigation and prevent long term salinity and sodicity problems. The data from the column experiments was used to evaluate the quantification of the soil structure degradation in UNSATCHEM. The resultant simulations for the soil columns showed that the estimated outflow and hydraulic conductivity were less than the experimental measurements, which suggested that the soil structure degradation was not accounted for properly. The sodicity effect was accounted for in UNSATCHEM by a reduction function, which is a combined function of the McNeal (1968) clay swelling model and the Simunek et al. (1996) pH effect equations. The empirical pH effect equation accounts for the reduction of the conductivity due to increasing pH and clay swelling. The evaluation of UNSATCHEM under highly sodic conditions suggests that the hydraulic conductivity reduction function is limiting the UNSATCHEM performance. Consideration of the first term of the hydraulic conductivity reduction function (i.e. the McNeal (1968) clay swelling model) has highlighted the weaknesses of the McNeal model and led to develop a generic clay swelling model (GCSM). Calibration of the GCSM using the data of McNeal showed good agreement between the estimated and measured relative conductivity data. Further calibration of the GCSM using relative conductivity data obtained for five local soils also showed good agreement between the model estimation and the measured data. Coding of the generic clay swelling model into UNSATCHEM and re-simulating the column experiments showed that the modelling process is improved compared with the UNSATCHEM version containing the McNeal (1968) clay swelling model. However, the outflow and conductivity values produced were still less than measured values. This result suggested that further investigations are required to identify the effect of pH on the change of hydraulic conductivity, cation exchange capacity, and the exchangeable sodium percentage. Further research is also required regarding bicarbonate chemistry during application of highly saline-sodic water.
Download or read book Australian Soils and Landscapes written by Neil McKenzie and published by CSIRO PUBLISHING. This book was released on 2004-07 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique compendium of the most important and widespread soils of Australia and their associated landscapes.
Download or read book Soil Guide written by and published by . This book was released on 2001 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geotechnical Engineering of Dams written by Robin Fell and published by CRC Press. This book was released on 2014-11-21 with total page 1374 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive text on the geotechnical and geological aspects of the investigations for and the design and construction of new dams and the review and assessment of existing dams. The book provides dam engineers and geologists with a practical approach, and gives university students an insight into the subject of dam engineering. All phases of investigation, design and construction are covered, through to the preliminary and detailed design phases and ultimately the construction phase. This revised and expanded 2nd edition includes a lengthy new chapter on the assessment of the likelihood of failure of dams by internal erosion and piping.
Download or read book Soil Physics and Rice written by International Rice Research Institute and published by Int. Rice Res. Inst.. This book was released on 1985 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Science of Clays written by Swapna Mukherjee and published by Springer Science & Business Media. This book was released on 2013-10-09 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an attempt to provide a comprehensive and coherent description of three widely separated aspects of clays: the science of clays; the industrial uses of clays; and the role of clays in the environment. Most of the existing literature lacks such an integrated study and this work endeavours to fill that gap. An exhaustive account of the science of clays is presented in Part I of the book, which includes the classification, origin and evolution, composition and internal structure, chemical and physical properties of clays; soil mechanics; and analytical techniques for determining clay constituents. Part II provides a comprehensive description of the applications of clays and their derivatives in various industries, while Part III describes the role of clays in the environment; the pollution caused by clay minerals; and the application of clays in order to prevent environmental hazards. A principal feature of the book is its explanation of how the structure and composition of particular clay types facilitate their specific industrial or environmental applications, thus describing the interrelationship between three widely varying aspects of clay. A number of thought-provoking questions are raised at the end of the work in order to leave readers with a better insight in this regard.
Download or read book Fundamentals of Soil Behavior written by James K. Mitchell and published by . This book was released on 1993 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explains the factors which determine and control the engineering properties of soils--particularly volume change, deformation, strength and permeability. New to this edition: expanded coverage of residual and tropical soils, environmental aspects of soil behavior, material on partly saturated soils, revised treatment of direct or coupled hydraulic, chemical, thermal and electrical flows through soil.
Download or read book Soil Mechanics written by R. F. Craig and published by Springer. This book was released on 2013-12-20 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended primarily to serve the needs of the undergraduate civil engineering student and aims at the clear explanation, in adequate depth, of the fundamental principles of soil mechanics. The understanding of these principles is considered to be an essential foundation upon which future practical experience in soils engineering can be built. The choice of material involves an element of personal opinion but the contents of this book should cover the requirements of most undergraduate courses to honours level. It is assumed that the student has no prior knowledge of the subject but has a good understanding of basic mechanics. The book includes a comprehensive range of worked examples and problems set for solution by the student to consolidate understanding of the fundamental principles and illustrate their application in simple practical situations. The International System of Units is used throughout the book. A list of references is included at the end of each chapter as an aid to the more advanced study of any particular topic. It is intended also that the book will serve as a useful source of reference for the practising engineer. In the third edition no changes have been made to the aims of the book. Except for the order of two chapters being interchanged and for minor changes in the order of material in the chapter on consolidation theory, the basic structure of the book is unaltered.
Download or read book Plant Metal Interaction written by Parvaiz Ahmad and published by Elsevier. This book was released on 2016-02-02 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant Metal Interaction: Emerging Remediation Techniques covers different heavy metals and their effect on soils and plants, along with the remediation techniques currently available. As cultivable land is declining day-by-day as a result of increased metals in our soil and water, there is an urgent need to remediate these effects. This multi-contributed book is divided into four sections covering the whole of plant metal interactions, including heavy metals, approaches to alleviate heavy metal stress, microbial approaches to remove heavy metals, and phytoremediation. - Provides an overview of the effect of different heavy metals on growth, biochemical reactions, and physiology of various plants - Serves as a reference guide for available techniques, challenges, and possible solutions in heavy metal remediation - Covers sustainable technologies in uptake and removal of heavy metals
Download or read book Soil Mineralogy with Environmental Applications written by Joe Boris Dixon and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Few books achieve a connection between scientifc theory and real world environmental problems, but this one does. Generous use of color images, exercises, and case studies make it friendly for the classroom or non-mineralogist. Discover crystallography, surface chemistry, mineral-solution equilibria, organic matter, and soil mineral analysis. The book includes a lengthy exploration of world-wide applications of mineralogy in soil taxonomy, tectonics, radionuclides, pesticides, enzymes, and more.
Download or read book Geoenvironmental Engineering written by Lakshmi Reddi and published by CRC Press. This book was released on 2000-04-18 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applies science and engineering principles to the analysis, design, and implementation of technical schemes to characterize, treat, modify, and reuse/store waste and contaminated media. Includes site remediation.
