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CONTENTS
page
Part A. INTRODUCTION 1
Preface 3
1. Why soil genesis?
1.1 What is soil genesis. 7
1.2 Why study soil genesis? 8
1.3 How to study soil genesis? 9
1.4 Answers 11
1.5 References 12
Part B. BASIC PROCESSES 13
2. Soil physical processes 15
2.1 Movement of water 15
2.2 Movement of solutes 18
2.3 Temperature effects 20
2.4 Shrinkage and swelling of soil aggregates and clays 20
2.5 Problems 27
2.6 Answers 35
2.7 References 39
3. Soil chemical processes 41
3.1 Chemical weathering and formation of secondary minerals 41
3.2 Soil minerals and their physico-chemical properties 51
3.3 Redox processes 62
3.4 Problems 67
3.5 Answers 71
3.6 References 79
4. Biological processes in soils 83
4.1 Input of plant litter into soils 83
4.2 Decomposition of plant litter and formation of soil organic matter 85
4.3 Kinetics of decomposition and of humus formation 87
4.4 Environmental factors influencing decomposition and humification 91
4.5 Formation of humus 95
4.6 Effects of soil fauna on soil properties 98
4.7 Nutrient cycling 102
4.8 Problems 106
4.9 Answers 110
4.10 References 118
