Biodiversity and Ecosystem Processes in Tropical Forests Book

1 Introduction Gordon H. Orians Rodolfo Dirzo J. Hall Cushman 1

References 8

2 Plant Species Diversity and Ecosystem Functioning in Tropical Forests S. Joseph Wright 11

2.1 Introduction 11

2.2 The Dependence of Ecosystem Processes on Species Diversity 12

2.3 Plant Species Richness in Tropical Forests 15

2.4 The Primary Productivity of Tropical Forests 17

2.5 The Stability of Tropical Forests 23

2.6 Conclusions 25

References 28

3 Consumer Diversity and Secondary Production Michael Huston Lawrence E. Gilbert 33

3.1 Introduction 33

3.2 Secondary Production and Biodiversity 34

3.3 Evolutionary Effects of Consumers on Ecosystem Properties 39

3.4 Ecological Effects of Consumers on Ecosystem Properties 40

3.4.1 Influence of Consumers on Plant Productivity 41

3.4.2 Influences of Consumers on Plant Diversity 44

3.5 Conclusion 44

References 46

4 Biodiversity and Biogeochemical Cycles Whendee L. Silver Sandra Brown Ariel Lugo 49

4.1 Introduction 49

4.1.1 Definitions and Concepts 49

4.2 Species Richness and Biogeochemical Cycling 52

4.3 Functional Diversity and Biogeochemistry 53

4.3.1 The Atmospheric-Terrestrial Interface 56

4.3.2 The Biotic Interface 57

4.3.3 The Plant-Soil Interface 58

4.3.4 The Terrestrial-Hydrologic Interface 59

4.4 Evidence from Experimental Studies 60

4.4.1 Plantations versus Natural Forests 60

4.4.2 Experimental Manipulation of Species Composition 63

4.5 Conclusions 64

References 65

5 Microbial Diversity and Tropical Forest Functioning D. Jean Lodge David Hawksworth Barbara J. Ritchie 69

5.1 Introduction 69

5.2 The Knowledge Base 69

5.3 Food Chains 70

5.4 Pathogens 74

5.4.1 Control of Herbivores by Pathogens 74

5.4.2 Pathogens as a Source of Distribution 74

5.4.3 Effect of Pathogens on Patterns of Tree Dispersion 76

5.5 Microbial Contributions to Global Biogeochemistry 77

5.5.1 Atmospheric CO₂ 77

5.5.2 Methane 78

5.5.3 Nitrous Oxide 78

5.5.4 Rock Weathering 79

5.6 Nutrient Cycling 80

5.6.1 Litter Decomposition and Soil Fertility 80

5.6.2 Symbiotic Nitrogen Fixation Associated with Plant Roots 82

5.6.3 Effects of Microbial Epiphylls and Epiphytes on Nutrient Fluxes 83

5.6.4 Mycorrhizae and Nutrient Uptake 84

5.7 Plant Endophytes 86

5.8 Threats to the Microbiota and the Processes They Mediate 87

5.8.1 Effects of Forest Fragmentation on Plant Symbioses 87

5.8.2 Effects of Forest Fragmentation on Cord-Forming Fungi 88

5.8.3 Effects of Acid Precipitation on Ectomycorrhizae 89

5.8.4 Effects of Air Pollution and Climate Change on Epiphyte Nitrogen Fixation 89

5.8.5 Are Decomposers Redundant in a Heterogeneous Environment? 90

5.9 Conclusions 90

References 93

6 Plant Life-Forms and Tropical Ecosystem Functioning John J. Ewel Seth W. Bigelow 101

6.1 Introduction 101

6.1.1 Functional Significance of Life-Forms 102

6.1.2 Assessing the Consequences of Life-Form Diversity 102

6.2 Classification 103

6.2.1 Stature 104

6.2.2 Longevity 106

6.3 Biogeographical Patterns 108

6.4 Environmental Correlates of Life-Form Diversity 109

6.4.1 Rainfall 109

6.4.2 Altitude 111

6.4.3 Soil Fertility 112

6.5 Episodic Impacts on Life-form Diversity 112

6.5.1 Wind 112

6.5.2 Fire 113

6.5.3 Animals 113

6.5.4 Climate change 115

6.6 Life-Forms and Succession 116

6.7 Implications of Loss of Life-Forms 116

6.8 Conclusions 121

References 123

7 Functional Group Diversity and Recovery from Disturbance Julie S. Denslow 127

7.1 Introduction 127

7.2 Functional Groups Affecting Tropical Forest Dynamics 128

7.2.1 Pioneer Herbs and Shrubs 128

7.2.2 Large-Leaved Understory Herbs and Shrubs 128

7.2.3 Small-Leaved Understory Herbs and Shrubs 130

7.2.4 Pioneer Trees 130

7.2.5 Understory Treelets 131

7.2.6 Emergent and Canopy Trees 131

7.2.7 Canopy Palms 132

7.2.8 Canopy Legumes 132

7.2.9 Vines and Lianas 133

7.2.10 Epiphytes 133

7.2.11 Seed Dispersers 133

7.2.12 Herbivorous Insects and Pathogens 133

7.2.13 Decomposers 134

7.2.14 Mycorrhizal Fungi 134

7.2.15 Soil-Churning Animals 134

7.3 Functional Groups and Natural Disturbance Processes in Tropical Moist Forests 135

7.4 Anthropogenic Disturbances to Tropical Forests 137

7.4.1 Functioned Groups Affect Successional Patterns 139

7.4.2 Causes of Depauperate Regeneration Pools 141

7.5 Functional Groups in Tropical Dry Forests 142

7.6 Redundancy within Functional Groups 145

7.7 Conclusions 145

References 147

8 Species Richness and Resistance to Invasion Marcel Rejmanek 153

8.1 Diversity vs. Stability 153

8.2 Global Patterns 155

8.3 Intentional Introductions 160

8.4 Invasions into Undisturbed Tropical Forests 163

8.5 Speculations 165

References 167

9 The Role of Biodiversity in Tropical Managed Ecosystems Alison Power Alexander S. Flecker 173

9.1 Introduction 173

9.2 Examples of Tropical Managed Ecosystems 174

9.2.1 Managed Forests 174

9.2.2 Home Gardens 174

9.2.3 Swidden Agriculture 175

9.2.4 Intensive Annual and Perennial Crops 176

9.2.5 Traditional Rice Systems 176

9.3 Plant Diversity and Primary Productivity 177

9.3.1 Comparisons Between Natural and Managed Ecosystems 177

9.3.2 Productivity of Diverse Cropping Systems 179

9.3.3 Stability of Diverse Cropping Systems 183

9.4 Plant Diversity and Primary Consumers 184

9.5 Plant Diversity and Secondary Consumers 186

9.5.1 Ants in Diverse Cropping Systems 188

9.6 Conclusions 189

References 191

10 Synthesis Gordon H. Orians Rodolfo Dirzo J. Hall Cushman 195

10.1 Introduction 195

10.2 Environmental Gradients 195

10.2.1 Moisture 195

10.2.2 Fertility 197

10.2.3 Elevation 198

10.3 Biodiversity and Functioning of Tropical Forests 198

10.4 Energy Flow 199

10.4.1 Carbon Allocation and Consumption 200

10.4.2 Animal-Animal Interactions 201

10.4.3 Detritus-Detritivores 201

10.5 Materials Processing 203

10.5.1 Atmosphere-Organism 203

10.5.2 Biotic Interface 204

10.5.3 Plant-Soil 204

10.5.4 Atmosphere-Soil 205

10.5.5 Soil-Water Table 205

10.6 Functional Properties over Longer Temporal Scales 206

10.6.1 Provision and Maintenance of Structure 206

10.6.2 Resistance to Invasions 206

10.7 Functional Properties Over Larger Spatial Scales 207

10.7.1 Movement of Materials by Physical Agents 208

10.7.2 Movement of Materials and Energy by Animals 208

10.8 Biodiversity and Responses to Disturbances 209

10.9 Research Agenda 210

10.10 Conclusions 211

References 214

Species Index 221

Topical Index 225