Environmetal Soil Properties and Behaviour

Environmetal Soil Properties and Behaviour


DisciplinaControle e Remediação da Poluição dos Solos5 materiais18 seguidores
Pré-visualização50 páginas
2.1 Introduction .........................................................................................25
2.1.1 Soil Composition ....................................................................25
2.1.2 Coarse-Grained Soils ............................................................. 26
2.1.3 Fine-Grained Soils ................................................................. 26
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2.2 Clay Minerals .......................................................................................28
2.2.1 Unit Cell, Layer, and Mineral Structure .............................28
2.2.2 Surface Functional Groups ...................................................30
2.2.3 Kaolin Group .......................................................................... 31
2.2.3.1 Mineral Structure ................................................... 31
2.2.3.2 Surface Functional Groups ................................... 32
2.2.4 Chlorites ..................................................................................33
2.2.4.1 Mineral Structure ...................................................33
2.2.4.2 Surface Functional Groups ...................................33
2.2.5 Smectites ..................................................................................33
2.2.5.1 Mineral Structure ...................................................33
2.2.5.2 Surface Functional Groups ...................................35
2.2.6 Micas, Illites, and Mixed-Layer Clays .................................35
2.2.7 Allophane ................................................................................38
2.2.7.1 Mineral Structure ...................................................38
2.2.7.2 Surface Functional Groups ...................................38
2.3 Nonclay Minerals ................................................................................38
2.3.1 Oxides, Hydroxides, and Oxyhydroxides .......................... 39
2.3.1.1 Basic Structure ........................................................ 39
2.3.1.2 Surface Functional Groups ...................................40
2.3.2 Carbonates and Sulphates .................................................... 41
2.4 Soil Organic Matter ............................................................................. 41
2.4.1 Characterization and Classification .................................... 41
2.4.2 Structure and Surface Functional Groups .........................42
2.4.2.1 Structure ..................................................................42
2.4.2.2 Surface Functional Groups ...................................43
2.5 Soil Particles .........................................................................................46
2.5.1 Size, Shape, and Texture of Particles ...................................46
2.5.1.1 Size and Shape ........................................................46
2.5.1.2 Texture ..................................................................... 47
2.5.2 Electrical Charges .................................................................. 47
2.5.2.1 Sources of Electrical Charges ............................... 47
2.5.2.2 Net Surface Charges and Surface 
Charge Density .......................................................48
2.5.3 Exchangeable Cations and Cation Exchange 
Capacity (CEC) ....................................................................... 51
2.5.4 Anion Sorption and Exchange .............................................54
2.5.5 Specific Surface Area (SSA) ..................................................55
2.6 Soil Structure ....................................................................................... 59
2.6.1 Soil Fabric and Structure ...................................................... 59
2.6.2 Granular Soil Packing ...........................................................60
2.6.3 Microstructure of Clays ........................................................ 62
2.7 Interparticle Bonds .............................................................................64
2.7.1 Forces and Bonding ...............................................................65
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2.8 Microorganisms in Soils ....................................................................66
2.8.1 Types of Microorganisms .....................................................66
2.8.1.1 Protozoa ...................................................................66
2.8.1.2 Fungi ........................................................................ 67
2.8.1.3 Algae ........................................................................68
2.8.1.4 Viruses .....................................................................68
2.8.2 Bacteria ....................................................................................68
2.8.3 Ecology in Soils ...................................................................... 70
2.8.4 Bacterial Growth Kinetics ..................................................... 71
2.9 Laboratory Determinations ............................................................... 74
2.9.1 Scope of Tests .......................................................................... 74
2.9.2 Soil Type and Mineral Analysis .......................................... 75
2.9.2.1 Soil Type ..................................................................75
2.9.2.2 Mineral Analysis .................................................... 76
2.9.2.3 Soil Fabric and Microstructural Features ........... 78
2.10 Concluding Remarks .......................................................................... 78
References ....................................................................................................... 79
 3. Soil\u2013Water Systems ......................................................................................83
3.1 Introduction .........................................................................................83
3.2 Water Retention ...................................................................................83
3.2.1 Granular (Cohesionless) Soils ..............................................84
3.2.1.1 Wetting and Drying ...............................................85
3.2.2 Cohesive Soils .........................................................................86
3.2.2.1 Hydration of Clays ................................................. 87
3.3 Clay\u2013Water Interactions .....................................................................88
3.3.1 Electrified Interface and Interactions ..................................88
3.3.1.1 Diffuse Double Layers ........................................... 89
3.3.1.2 Electric Potential \u3c8 .................................................90
3.3.2 Interaction Energies ............................................................... 93
3.3.2.1 Energies of Interaction in the Stern Layer .......... 93
3.3.2.2 London\u2013van der Waals Energy and Total 
Intermolecular Pair Potential................................ 93
3.3.2.3 DLVO Model and Particle 
Interaction Energies ............................................94
3.3.2.4 Energies in Particle Interaction and 
in Interlayer Space .................................................. 97
3.3.2.5 Calculated Swelling Pressures from 
Interaction Models .................................................99
3.4 Soil\u2013Water Energy Characteristics ................................................. 100
3.4.1 Concept of Soil\u2013Water Potential ........................................ 100
3.4.1.1 Components of Soil\u2013Water Potential ................. 103
3.4.2 Measurements of Soil\u2013Water Potentials ........................... 106
3.4.2.1 Tensiometer for in Situ Measurements ............. 106
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3.4.2.2 Tensiometer-Type Device for 
Laboratory Use .................................................107
3.4.2.3 Pressure-Membrane Techniques ........................