- •Foreword
- •Preface
- •Acknowledgements
- •Preamble
- •Contents
- •About the Authors
- •List of Figures
- •Abstract
- •1.1 Introduction
- •1.2 History of Soil Classification Systems
- •1.2.1 Soil Classification Systems
- •1.2.1.1 Australian Soil Classification System (2016)
- •1.2.1.2 Canadian Soil Classification System
- •1.2.1.3 Chinese Soil Taxonomy
- •1.2.1.4 England and Wales Soil Classification System
- •1.2.1.5 France Soil Classification System
- •1.2.1.6 Kuwait Soil Taxonomy Hierarchy
- •1.2.1.7 Norway Soil Classification System
- •1.2.1.8 Russian Soil Classification System
- •1.2.1.9 South African Soil Classification System
- •1.2.1.10 United Arab Emirates Keys to Soil Taxonomy
- •1.2.1.11 USDA-NRCS Keys to Soil Taxonomy
- •1.2.1.12 World Reference Base for Soil Resources (WRB Classification)
- •References
- •Abstract
- •2.1 Introduction
- •2.2 The Soil That We Classify
- •2.3 Lower Boundary of Soil
- •2.4 Nonsoil Materials
- •2.5 Buried Soils
- •References
- •Abstract
- •3.1 Introduction
- •3.2 Basic System of Horizon and Layer Designations
- •3.2.1 Master Horizons and Layers
- •3.2.2 Suffix Symbols
- •3.2.3 Conventions for Using Horizon Designation Symbols
- •3.2.4 Vertical Subdivisions
- •3.2.5 Discontinuities
- •3.2.6 The Prime Symbol
- •3.2.7 The Caret Symbol
- •3.3 Diagnostic Surface and Subsurface Horizons
- •3.3.1 The Epipedon
- •3.3.1.1 Ochric Epipedon
- •3.3.2 Diagnostic Subsurface Horizons
- •3.3.2.1 Anhydritic Horizon
- •3.3.2.2 Argillic Horizon
- •3.3.2.3 Calcic Horizon
- •3.3.2.4 Cambic Horizon
- •3.3.2.5 Gypsic Horizon
- •3.3.2.6 Petrocalcic Horizon
- •3.3.2.7 Petrogypsic Horizon
- •3.3.2.8 Salic Horizon
- •3.4 Diagnostic Soil Characteristics
- •3.4.1 Free Carbonates
- •3.4.2 Identifiable Secondary Carbonates
- •3.4.3 Aquic Conditions
- •3.4.4 Lithic Contact
- •3.4.5 Soil Moisture Regimes
- •3.4.5.1 Soil Moisture Control Section
- •3.4.5.2 Classes Soil Moisture Regimes
- •3.4.6 Soil Temperature Regimes
- •References
- •4 Families and Series Differentiae
- •Abstract
- •4.1 Introduction
- •4.2.1 Control Section for Particle-Size Classes
- •4.2.1.1 Root-Limiting Layers
- •4.2.1.3 Key to the Particle-Size and Substitute Classes
- •4.3 Mineralogy Classes
- •4.3.1 Control Section for Mineralogy Classes
- •4.3.2 Key to Mineralogy Classes
- •4.4.1 Use of the Cation-Exchange Activity Classes
- •4.4.3 Key to Cation-Exchange Activity Classes
- •4.5 Soil Temperature Class
- •4.5.1 Control Section for Soil Temperature
- •4.5.2 Key to Soil Temperature Class
- •4.6 Soil Depth Classes
- •4.6.1 Key to Soil Depth Classes
- •4.7 Series Differentiae Within a Family
- •4.7.1 Control Section for the Differentiation of Series
- •4.7.1.1 Key to the Control Section for the Differentiation of Series
- •References
- •Abstract
- •5.1 Introduction
- •5.2 Soil Orders Identified in Kuwait
- •5.2.1 Aridisols
- •5.2.2 Entisols
- •5.3 Understanding Soil Taxonomic Classes
- •5.4 Key to Soil Orders
- •5.5 Key to Suborders of Aridisols
- •5.5.1 Argids
- •5.5.2 Calcids
- •5.5.3 Cambids
- •5.5.4 Gypsids
- •5.5.5 Salids
- •5.6 Key to Suborders of Entisols
- •5.6.1 Orthents
- •5.6.2 Psamments
- •References
- •Abstract
- •6.1 Introduction
- •6.2 Soil Orders
- •6.2.1 Entisols
- •6.2.2 Aridisols
- •6.3 Soil Suborders
- •6.4 Soil Great Groups
- •6.5 Soil Subgroups
- •6.6 Soil Families
- •6.6.1 Families in the Soil Order Aridisols
- •6.6.2 Families in the Soil Order Entisols
- •6.7.1 Hypergypsic Mineralogy
- •6.7.2 Gypsic Mineralogy
- •6.7.3 Carbonatic Mineralogy
- •6.7.4 Mixed Mineralogy
- •6.7.5 Shallow
- •6.7.6 Coarse-Gypseous
- •6.7.7 Sandy-Skeletal
- •6.7.8 Sandy
- •6.7.9 Loamy
- •6.7.10 Coarse-Loamy
- •6.7.11 Fine-Loamy
- •6.7.12 Hyperthermic
- •References
- •Abstract
- •7.1 Introduction
- •7.2 Soil Samples Collection, Preparation and Processing
- •7.4 Coarse Fragments
- •7.5 Moisture Content
- •7.6 Loss on Acid Treatment (LAT)
- •7.9 Extractable Cations
- •7.11 Exchangeable Sodium Percentage (ESP)
- •7.12 Saturation Percentage (SP)
- •7.13 Preparation of Saturated Soil Paste
- •7.14 Saturation Extract Analysis
- •7.15 Electrical Conductivity of Soil Saturation Extract (ECe)
- •7.16 Osmotic Potential (OP)
- •7.17 Soil Reaction or Hydrogen Ion Activity (pH)
- •7.18 Sodium Adsorption Ratio (SAR)
- •7.19 Water Retention
- •7.20 Bulk Density (BD)
- •7.21 Particle Density (PD)
- •7.22 Porosity
- •7.23 Soil Organic Matter and Organic Carbon
- •7.24 Engineering Data
- •7.24.1 Atterberg Limits
- •7.24.1.1 Liquid Limit (LL)
- •7.24.1.2 Plastic Limit (PL)
- •7.24.1.3 Plasticity Index (PI)
- •7.24.2 Percent Passing Sieves
- •7.24.3 Unified Soil Classification System (USCS)
- •7.24.4 AASHTO Group Classification
- •7.25 Soil Mineralogy
- •7.26 Clay Mineralogy
- •7.26.1 X-Ray Diffraction Criteria
- •References
- •Author Index
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4 Families and Series Differentiae |
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4.7Series Differentiae Within a Family
The criteria most commonly used include presence of, depth to, thickness of, and expression of horizons and properties diagnostic for the higher categories and differences in texture, mineralogy, soil moisture, soil temperature, and amounts of organic matter. The limits of the properties used as differentiae must be more narrowly defined than the limits for the family. The properties used, however, must be reliably observable or be inferable from other soil properties or from the setting or vegetation. The differentiae used must be within the series control section. Differences in soil that are outside the series control section and that have not been recognized as series differentiae but are relevant to potential uses of certain soils are considered as a basis for phase distinctions.
4.7.1 Control Section for the Differentiation of Series
The control section for the soil series is similar to that for the family, but it differs in a few important respects. The particle-size and mineralogy control sections for families end at the upper boundary of certain diagnostic subsurface horizons, such as a petrocalcic horizon, petrogypsic horizon because these horizons have few roots. The thickness of such root-limiting horizons is taken into account in differentiating concepts of competing soil series, when they occur within the series control section. The series control section includes materials starting at the soil surface and extends into the first 25 cm of densic materials, a manufactured layer, or paralithic materials, if the densic, manufactured layer, or paralithic contacts, respectively, are less than 125 cm below the mineral soil surface. In contrast, the properties of materials below any densic, lithic, manufactured layer, paralithic, or petroferric contact are not used for classification in the categories above the series (i.e., order through family). The properties of horizons and layers below the particle-size control section, a depth between 100 and 150 cm (or to 200 cm if in a diagnostic horizon) from the mineral soil surface, also are considered in the series category of this taxonomy.
4.7.1.1Key to the Control Section for the Differentiation of Series
The part of a soil to be considered in differentiating series within a family is as follows: Mineral soils: From the soil surface to the shallowest of the following.
1.A Lithic contact; or
2.A depth of either 25 cm below a densic, manufactured layer, or paralithic contact or 150 cm below the soil surface, whichever is shallower, if there is a densic, manufactured layer, or paralithic contact within 150 cm; or