Shifting cultivation and secondary succession in the Tropics

Contents......Page 6
Preface......Page 10
Acknowledgements......Page 12
1.1 Definition of the Tropics......Page 14
1.2.2 Tropical wet–dry (savanna) climate......Page 15
1.2.5 Mild temperate (mesothermal) climate......Page 16
1.3.1 Tropical rainforest......Page 17
1.3.2 Savanna......Page 18
1.3.4 Desert and semi-desert......Page 19
1.5 Soils......Page 20
1.5.4 Inceptisols......Page 21
1.5.5 Entisols......Page 22
1.6.1 Low per-capita income......Page 23
1.6.5 Poverty......Page 24
1.7 Agriculture......Page 25
1.7.3 Plantation agriculture......Page 26
References......Page 27
2.1 Definition......Page 29
2.2 Characteristics of Shifting Cultivation......Page 31
2.3 Why Fields are Shifted......Page 32
2.4 Forms of Shifting Cultivation......Page 34
2.4.1 Slash-and-burn agriculture in forest and savanna lowlands......Page 35
2.4.2 The chitemene system......Page 36
2.4.4 Shifting cultivation in the Orinoco floodplain......Page 37
2.4.5 The slash–mulch system......Page 38
2.4.6 The plough-in-slash system......Page 39
References......Page 41
3.1 Effects of Vegetation Clearing......Page 43
3.1.4 Forest nutrient cycle......Page 44
3.1.5 Savanna nutrient cycle......Page 46
3.1.6 Nutrient cycling in shifting cultivation agroecosystems......Page 49
3.2.2 Effects on the soil......Page 50
3.3 Organic Matter Decline......Page 53
3.4 Nutrient Decline during Cropping......Page 56
3.5 Decline in Soil Physical Status......Page 57
3.6 Erosion......Page 58
3.7 Shifting Cultivation in River Floodplains......Page 59
References......Page 60
4.1 Soil Organic Matter Dynamics......Page 64
4.1.1 Organic matter equilibrium concept......Page 66
4.1.2 Organic matter equilibrium concept: an explanatory model......Page 67
4.1.3 Organic matter accretion in fallow soil in different ecological zones......Page 68
4.2.1 Forest fallows......Page 70
4.2.2 Savanna fallows......Page 74
4.3 Improvement in Soil Physical Status......Page 75
4.4 Soil Organic Matter and Nutrient Dynamics in High-altitude Fallows......Page 76
References......Page 79
5.1.1 Intangible benefits......Page 82
5.1.2 Tangible benefits......Page 83
5.2 Rainforest Succession......Page 86
5.2.1 General features of rainforest secondary succession......Page 87
5.2.2 Characteristics of secondary or successional tree species......Page 88
5.2.3 Changes infloristic composition of vegetation......Page 89
5.2.4 Changes in number of species and species diversity......Page 92
5.2.5 Changes in vegetation structure......Page 93
5.3 Succession in Deciduous Seasonal (Monsoon) Forest......Page 95
5.4 Succession in Savanna Ecosystems......Page 98
5.4.2 Succession in savanna vegetation subjected to burning......Page 99
5.4.3 Succession in fire-protected savanna vegetation......Page 100
5.4.4 Succession in fire-protected savanna plots in West Africa......Page 102
5.4.5 Succession in fire-protected savanna in South America......Page 103
5.5 Dellected Succession......Page 104
5.5.2 Dellected succession in tropical Asia......Page 105
5.6 Succession in Areas of High Altitude on Tropical Mountains......Page 106
5.7 Management of Fallow Vegetation......Page 109
5.8 Nutrient Storage in Fallow Vegetation......Page 110
References......Page 112
6 Relationships between Fallow Soil and Vegetation......Page 116
6.1.1 Relationships between plant life forms and soil properties......Page 118
6.1.2 Relationships between vegetation structural/floristic characteristics and soil chemical properties......Page 121
6.2 Fallow Soil–Vegetation Interrelationships: Multiple Regression Analysis......Page 122
6.3 Implications of Fallow Soil–Vegetation Interrelationships......Page 126
References......Page 127
7 Ecological Succession Theory and Models......Page 129
7.2 Types of Ecological Succession......Page 130
7.3.1 The Clementsian holistic hypothesis......Page 131
7.3.2 The individualistic theory......Page 133
7.3.3 The resource-ratio hypothesis......Page 134
7.3.4 The initial floristic composition hypothesis......Page 135
7.3.5 The facilitation, in hibition and tolerance hypotheses......Page 136
7.3.7 The nucleation model......Page 137
7.4 Changes that Occur in Ecosystems during Succession......Page 138
7.5.1 Monoclimax concept......Page 140
7.5.2 Polyclimax concept......Page 141
References......Page 142
8.1 Guillemin’s Model......Page 144
8.2 The Sigmoid Model......Page 146
8.3 Trenbath’s Models......Page 147
8.4.1 Core–periphery analogy......Page 149
8.4.2 Stages of the process of soil fertility restoration......Page 150
8.5 A Unified Theory of Succession and Soil Fertility Restoration......Page 154
References......Page 157
9 Intensification of Shifting Cultivation......Page 159
9.1 Palm Fallows......Page 160
9.2.1 Tree legumes in farms in Java......Page 162
9.2.2 Trees in farms and fallows of Bora Indians, Peru......Page 163
9.3.1 Pada in rice fields and fallow vegetation in northern Thailand......Page 164
9.3.2 Gliricidia-enriched fallows of south-western Nigeria......Page 165
9.4 Planted Fallows......Page 166
9.4.1 Seasonal or short-duration fallows......Page 167
9.4.2 Multi-seasonal or long-duration planted fallows......Page 169
9.5 Agroforestry......Page 170
9.5.1 Faidherbia (Acacia) albida-based agroforestry in tropical African savanna......Page 171
9.5.2 Leguminous/commercial trees in farms in the Chittagong Hill Tracts of Bangladesh......Page 172
9.5.5 Maize cultivation intensification with soybean in Zimbabwe......Page 173
9.5.6 Hedgerow intercropping in south-eastern Nigeria......Page 174
9.6 Compost......Page 175
9.7 Green Manure and Cover Crops......Page 176
9.9 Socio-economic and Technological Aspects of Intensification......Page 177
References......Page 179
10.1 Continuous Cultivation Based on Application of Inorganic Fertilizers......Page 182
10.1.1 Problems associated with the use of inorganic fertilizers......Page 184
10.2 Continuous Cultivation Based on Manure Application......Page 185
10.3 Alley Farming......Page 186
10.3.1 Adoption of alley farming by small-scale farmers......Page 188
10.4 Quesungual Slash-and-Mulch Agroforestry System......Page 189
10.5.2 Reduced tillage......Page 191
10.5.3 Organic farming......Page 192
10.5.4 Agricultural innovation and global warming......Page 193
10.5.5 Deforestation......Page 194
10.6 The Future of Shifting Cultivation......Page 195
10.6.1 Stages and processes of intensifying shifting cultivation......Page 196
10.6.2 Effects of land grabbing......Page 198
10.6.3 Agricultural imperialism......Page 200
References......Page 201
C......Page 204
F......Page 205
M......Page 206
S......Page 207
Z......Page 209