CONTENTS Preface Foreword Acknowledgements Chapter 1: Soil Physics 1.1 Soil: From the view point of soil physics 1.2 Mass volume relationship of soil constituents 1.2.1 Mean particle density 1.2.2 Dry bulk density 1.2.3. Total wet bulk density 1.2.4. Dry specific volume 1.2.5. Porosity 1.2.6. Void ratio 1.2.7. Soil wetness 1.2.7.1 Mass wetness 1.2.7.2 Volume wetness 1.2.7.3 Water volume ratio 1.2.7.4 Degree of saturation 1.2.8 Air-filled porosity 1.2.9 Total porosity 1.2.10 Additional interrelations 1.3 Soil Texture 1.3.1 Particle size distribution 1.3.2 Stoke?s law 1.3.3 Assumptions in Stoke?s law 1.3.4 Stoke?s Law - limitations 1.4 Soil structure and aggregation 1.4.1 Genesis of soil structure 1.4.2 Soil structure management 1.5 Soil colour 1.6 Soil consistency 1.7 Soil plasticity 1.7.1 Plasticity indices: Atterbergs limits 1.7.2 Coefficient of Linear Extensibility (COLE) 1.8 Soil compaction 1.8.1 Soil compression vis-?-vis soil compaction 1.9 Soil crusting 1.1 Hydration 1.11 Swelling 1.12 Specific surface 1.13 Soil tilth and tillage 1.14 Soil conditioners 1.15 Soil water energetics 1.16 Total soil water potential 1.16.1 Gravitational potential 1.16.2 Pressure potential 1.16.2.1 Submergence potential 1.16.3 Matric potential 1.16.4 Pneumatic potential 1.16.5 Osmotic potential 1.16.6 Soil moisture potential ? units 1.17 Soil moisture characteristic curve 1.18 Differential water capacity 1.19 Hysteresis 1.2 Flow of water in a saturated soil (Horizontal flow) : Darcy?s law 1.20.1 Limitations of Darcy?s law 1.21 Hydraulic conductivity, permeability and fluidity 1.22 Reynolds number 1.23 Soil water flow through a vertical soil column under saturated condition 1.24 Equations of saturated flow(horizontal flow):Laplace equation 1.25 Flow of water in unsaturated soil 1.25.1 Saturated versus unsaturated flow 1.26 Equations of unsaturated flow 1.27 Soil water diffusivity 1.28 Infiltration 1.28.1 Soil water infiltration equation 1.28.1.1 Philip?s equation 38 1.28.1.2 Kostiakov equation 40 1.29 Redistribution of soil moisture 1.3 Soil water balance 1.31 Evaporation 1.31.1 Evaporation under steady conditions in presence of water table. 1.31.2 Evaporation under non steady conditions in absence of water table 1.31.3 Penman - Monteith equation 1.31.4 Beneficial and adverse effects of evaporation 1.32 Ground water drainage 1.32.1 Water table 1.32.1.1 Perched water table 1.32.2 Drainage design (Hooghout?s equation) 1.33 Solute transport 1.34 Diffusion 1.35 Hydrodynamic dispersion 1.36 Soil Air 1.37 Characterization of soil aeration status 1.37.1 Total air capacity 1.37.2 Composition of soil air 1.37.3 Equivalent diffusion distance 1.37.4 Aeration factor 1.37.5 Oxygen Diffusion Rate (ODR) 1.37.6 Air filled porosity: 1.38 Dynamics of soil air 1.38.1 Mass flow 1.38.2 Diffusion 1.39 Soil aeration in relation to plant growth 1.4 Soil aeration management 1.41 Soil temperature in relation to plant growth 1.42 Thermal properties of soil 1.42.1 Heat capacity 1.42.2 Thermal conductivity 1.42.3 Thermal diffusivity 1.43 Heat transfer through soil ? Flow equations 1.44 Energy balance equation 1.45 Soil temperature management 1.46 Management of soil physical constraints 1.47 Soil Rheology 1.47.1 Strain 1.47.2 Stress 1.47.3 Hooke?s law 1.47.4 Poisson?s ratio 1.47.5 Modulus of rigidity 1.47.6 Bulk modulus Chapter 2: Soil Chemistry 2.1 Physical chemistry of soil colloids 2.2 Surface chemistry of soil clays 2.3 Charge development on soil colloids 2.3.1 Permanent charge 2.3.2 pH - dependant charge 2.4 Zero Point Charge (ZPC) 2.4.1 Point of Zero Net Charge (PZNC) 2.4.2 Point of Zero Net Proton Charge (PZNPC) 2.4.3 Point of Zero Salt Effect (PZSE) 2.4.4 Important equations for charge calculation 2.5 Concept of ?Electrical double layer? in clay colloids 2.6 Zeta potential 2.6.1 Zeta potential and mechanism of flocculation. 79 2.7 Effect of flocculation and dispersion upon plant growth 2.8 Adsorption and Ion Exchange 2.8.1 Nature of adsorption 2.8.2 Freundlich isotherm 2.8.3 Langmuir adsorption isotherm 2.8.4 Brunauer, Emmett and Teller (BET) Equation 2.8.5 Gibb?s adsorption isotherm 2.9 Ion exchange 2.9.1 Cation Exchange Capacity(CEC) 2.9.2 Base Saturation 2.9.3 Complementary cations 2.9.4 Colloid specific effect 2.9.5 Cation exchange selectivity 2.9.6 Ion exchange equations 2.9.6.1 Gapon equation 2.9.6.2 Kerr equation 2.9.6.3 Vanselow equation 2.9.2 Anion exchange 2.9.2.1 Factors affecting anion exchange 2.1 Schofield?s ratio law 2.11 Mass Flow and diffusion 2.12 Soil organic matter 2.12.1 Role of soil organic matter in soil fertility 2.13 Humus 2.13.1 Hypothesis of humus formation 2.13.2 Humus Fractionation 2.13.3 Beneficial role of humus 2.14 Mechanism of formation of clay ? Humus complex 2.14.1 Adsorption or bonding through Vanderwalls force 2.14.2 Polyvalent metal cation bonding mechanism 2.14.3 Ligand Exchange 2.15 Soil acidity and acid soils 2.15.1 Acid soils of India 2.15.1.1 Soils with overlying organic matter 2.15.1.2 Acid mineral soils without overlying organic matter 2.15.1.3 Degraded alkali soils 2.15.1.4 Acid sulphate soils or cat clays 2.15.2 Types of soil acidity 2.15.2.1 Active Acidity 2.15.2.2 Exchangeable Acidity 2.15.2.3 Potential (Reserve) Acidity 2.15.3 Productivity constraints in acid soils 2.15.4 Management of acid soils 2.15.4.1 Acid soil management in relation to physical properties 2.15.4.2 Acid soil management in relation to chemical properties 2.15.4.3 Lime requirement 2.16 Salt affected soils 2.16.1 Distribution 2.16.2 Important soil characteristics 2.16.2.1 Parameters indicating soil alkalinity (ESP and SAR) 2.16.3 Constraints and Management 2.17 Nutrient transformation 2.17.1. N-transformation 2.17.1.1 Mechanism of biological N ? fixation 2.17.1.2 Biological N ? fixation systems 2.17.1.3 Ammonification and nitrification 2.17.1.4 Nitrogen mineralization and immobilization 2.17.1.5 Denitrification 2.17.1.6 Carbon:Nitrogen (C:N) ratio 2.17.2 P-transformation 2.17.2.1 Fixation and release of phosphorus in soils 2.17.2.2 Biological transformation of phosphorus 2.17.3 S-transformation 2.17.3.1 Biological transformation of sulphur 2.17.4 K-transformation 2.18 Submerged soils 2.19 Soil quality 2.2 Soil pollution 2.21 Soil mineralogy 2.21.1 Primary mineral 2.21.2 Secondary minerals (Clay minerals) 2.21.2.1 Identification of clay minerals 2.22 Soil testing 2.23 Instrumental method: Fundamental concepts 2.23.1 Colorimetry and Sectrophotometry 2.23.2 General features of spectroscopy 2.23.3 Flame Spectrometry (Atomic Absorption Spectrometry and Flame Photometry) 2.23.3.1 Flame photometry 2.23.3.2 Atomic absorption spectrophotometer (AAS) 2.23.4 Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP) 2.24 Soil chemical analysis: Underlying principles 2.24.1 pH 2.24.2 Soil acidity 2.24.2.1 Total acidity 2.24.2.2 Exchange acidity 2.24.2.3 Extractable acidity 2.24.2.4 Total Potential Soil Acidity 2.24.2.5 pH ? dependent soil acidity 2.24.3 Electrical conductivity 2.24.4 Organic carbon 2.24.5 Total nitrogen (Modified Kjeldahl?s Method) 2.24.6 Mineralisable nitrogen 2.24.7 Total phosphorus 2.24.8 Extractable phosphorus 2.24.8.1 Ammonium fluoride-hydrochloric acid extractable phosphorus of soils: (Bray?s 1 method) 2.24.8.2 Alkaline extraction of soil phosphorus (Olsen?s method) 2.24.9 Total potassium 2.24.10 Ammonium acetate extractable potassium 2.24.11 Cation Exchange Capacity (CEC) 2.24.11.1 Cation Exchange Capacity of soils containing calcium carbonate 2.24.12 Anion Exchange Capacity (AEC) 2.24.13 Exchangeable bases 2.24.13.1 Exchangeable Sodium 2.24.13.2 Exchangeable Calcium and Magnesium 2.24.14 Micronutrients: DTPA Extractable Zn2+, Cu2+, Fe2+, Mn2+ 2.24.15 Available boron 2.24.16 Available molybdenum 2.24.17 Arsenic determination by conversion to their hydrides and aspiration into an AAS 2.24.18 Selenium determination by conversion to their hydrides and aspiration into an AAS 2.24.19 Fluoride estimation in soil and water: SPADNS method 2.24.20 Determination of lime requirement of soil 2.24.21 Determination of gypsum requirement of soil 2.24.22 Determination of lime potential 2.24.23 Available sulphur determination in soil. Chapter 3 : Pedology 3.1 Pedology versus edaphology 3.2 Soil-defined 3.2.1 Soil as a natural body 3.2.2 Soil as a porous body 3.2.3 Soil as a disperse system 3.3 Components of soils 3.4 Top soil versus subsoil 3.5 Land and soil 3.6 Functions of soil 3.7 Parent material 3.7.1 Geological classification of parent materials 3.7.2 Soil properties as influenced by parent material 3.8 Soil profile 3.9 Mineral matter (inorganic constituents) in soils 3.1 Soil organic matter 3.11 The pedon versus polypedon 3.12 Soil water 3.13 Soil air 3.14 Rock forming minerals 3.15 Different types of rocks 3.16 Weathering 3.16.1 Processes of weathering 3.16.1.1 Mechanical processes 3.16.1.2 Chemical processes 3.16.1.3 Biological weathering 3.16.2 Weathering of rocks 3.16.2.1 Igneous rocks and weathering process 3.16.2.2 Sedimentary rocks and weathering process 3.16.3 Weathering of minerals 3.16.3.1 Weathering and formation of secondary minerals 3.16.4 Factors responsible for weathering of minerals 3.16.5 Stability order of minerals relative to weathering 3.16.5.1 Weathering sequence 3.17 Soil formation 3.17.1 Different stages of soil formation 3.17.2 Soil forming factors: Governing equations 3.17.3 Active soil forming factors 3.17.4 Passive soil forming factors 3.17.5 Endo and ectodynamomorphic soils 3.17.6 Four fold categorization in relation to soil formation 3.18 Pedogenic processes 3.18.1 Fundamental processes in pedogenesis 3.18.2 Specific processes in pedogenesis 3.19 Soil classification: Introduction 3.19.1 Historical background of soil classification systems 3.19.2 Early systems of soil classification 3.19.3 Worldwide system of soil classification 3.19.4 Limitations in the genetic system of soil classification. 3.19.5 Advantages of considering USDA soil classification (Soil Taxonomy) 3.19.6 Soil Taxonomy :A comprehensive US system of soil classification 3.19.7 Diagnostic horizons 3.19.7.1 Features of Epipedons 3.19.7.2 Features of Endopedons 3.19.8 Structure of soil taxonomy 3.19.9 Place of Indian soils in US system of soil classification 3.2 Geoinformatics 3.20.1 Remote Sensing 3.20.2 Geographic Information System (GIS) : Introduction 3.20.3 Global Positioning System (GPS) 3.21 Soil survey and mapping 3.21.1 Objective of soil survey 3.21.2 Types of soil survey 3.21.3 Sequence of survey operations 3.21.4 Soil Resource Mapping (SRM): A 3-tier approach 3.21.5 Modern approach for soil survey and mapping 3.21.6 Soil correlation 3.22 Land evaluation 3.22.1 Land evaluation: approaches 3.22.2 Land capability classification 3.22.3 Land suitability for land evaluation 3.22.4 Land irrigability classification 3.23 Land use planning 3.24 Soils of India 3.24.1 Geographical settings 3.24.2 Climate 3.24.3 Geology 3.24.4 Soil groups of India References Suggested Readings