Details

Savanna Woody Plants and Large Herbivores

1. Aufl.

von: Peter Frank Scogings, Mahesh Sankaran
125,99 €
Verlag:	Wiley
Format:	EPUB
Veröffentl.:	16.10.2019
ISBN/EAN:	9781119081135
Sprache:	englisch
Anzahl Seiten:	784

In den Warenkorb

Als Gutschein

DRM-geschütztes eBook, Sie benötigen z.B. Adobe Digital Editions und eine Adobe ID zum Lesen.

Beschreibungen

Titelbeschreibung

Insights on current research and recent developments in understanding global savanna systems Increasingly recognized as synonymous with tropical grassy biomes, savannas are found in tropical and sub-tropical climates as well as warm, temperate regions of North America. Savanna Woody Plants and Large Herbivores examines the interactions between woody plants and browsing mammals in global savannas—focusing primarily on the C4 grassy ecosystems with woody components that constitute the majority of global savannas—and discusses contemporary savanna management models and applications. This much-needed addition to current research examines topics including the varying behavior of browsing mammals, the response to browsing by woody species, and the factors that inhibit forage intake. Contributions from an international team of active researchers and experts compare and contrast different savanna ecosystems, offering a global perspective on savanna functioning, the roles of soil and climate in resource availability and organism interaction, and the possible impacts of climate change across global savannas. <ul> <li>Fills a gap in literature on savanna management issues, including biodiversity conservation and animal production</li> <li>Applies concepts developed in other biomes to future savanna research</li> <li>Complements contemporary books on savanna or large herbivore ecology</li> <li>Focuses on the woody component of savanna ecosystems and large herbivore interactions in savannas</li> <li>Compares tree-mammal systems of savannas and other eco-systems of temperate and boreal regions</li> <li>Provides numerous case studies of plant-mammal interactions from various savanna ecosystems</li> </ul> Savanna Woody Plants and Large Herbivores is a valuable addition to those in fields such as ecology, wildlife and conservation biology, natural resource management, and environmental science.

Inhaltsverzeichnis

List of Contributors xv Preface xix Part I Introduction 1 1 Distribution and Determinants of Savannas 3 Sally Archibald, William J. Bond, William Hoffmann, Caroline Lehmann, Carla Staver, and Nicola Stevens 1.1 Introduction 3 1.2 Evolutionary History of Savanna Vegetation and Fauna 4 1.3 Defining Savannas 7 1.3.1 Are Savannas Tropical Systems? 7 1.3.2 Distinguishing Savannas from Grasslands 7 1.3.3 Distinguishing Savannas from Forests 8 1.4 Global Determinants of Savannas 9 1.4.1 Mesic Transition: Points of Contention 10 1.4.1.1 The Role of Nutrients 10 1.4.1.2 Rainfall Seasonality 10 1.4.2 Mesic Transition: Toward Resolution 11 1.4.3 Mesic Transition: Unresolved Ideas 12 1.4.4 Arid Transition 12 1.4.5 Arid Transition: Toward Resolution 13 1.4.6 Determinants of Temperate Savannas 14 1.5 Functional Differences Between Savannas 14 1.5.1 Temperate vs Tropical Savannas 14 1.5.2 Functional Differences Within Tropical Savannas 15 1.6 Conclusions and the Future of Savanna Ecosystems 17 References 17 2 African and Asian Savannas: Comparisons of Vegetation Composition and Drivers of Vegetation Structure and Function 25 Jayashree Ratnam, Chintan Sheth, and Mahesh Sankaran 2.1 Introduction 25 2.2 Climate and Vegetation Formations 27 2.3 Fine‐Leaved and Broad‐Leaved Savannas: Vegetation Structure, Composition, and Geographic Distribution 30 2.4 Role of Bottom‐Up Drivers in Regulating Vegetation Structure: Climate and Soil Nutrients 33 2.5 Role of Top‐Down Forces: Fire and Herbivory 36 2.6 African and Asian Savannas in the Anthropocene 40 References 42 3 Savannas of Australia and New Guinea: Vegetation and the Functional Role of Extant and Extinct Fauna 51 Garry D. Cook, William J. Bond, Edmund C. February, and Richard J. Williams 3.1 Introduction 51 3.2 The Biota of Australia’s and New Guinea’s Savannas 51 3.3 Climate, Landforms, and Fire 53 3.4 Human History and Impacts 54 3.5 Are Native Mammals Irrelevant? 55 3.6 Was Ecosystem Functioning Different Prior to Human Dispersal to Australia? 57 3.7 Critique of the “Nutrient Poverty/Intense Fire” Theory 58 3.8 Australia’s Lost Megafauna 61 3.9 Habitat Variation and the Pleistocene Megafauna 64 3.10 Impacts of Herbivores in Australian Savannas 64 3.11 Toward a New Hypothesis of Plant–Animal Interactions in Australian Savannas 66 References 67 4 South American Savannas 77 Fabian Borghetti, Eduardo Barbosa, Leandro Ribeiro, José Felipe Ribeiro, and Bruno Machado Teles Walter 4.1 Introduction 77 4.2 Origin of South American Savannas 77 4.3 Distribution and Diversity of South American Savannas 78 4.4 Northern Savannas 80 4.4.1 Colombo–Venezuelan Llanos 80 4.4.1.1 Orinoco Llanos 80 4.4.1.2 Llanos Orientales 84 4.4.2 Gran Sabana 85 4.4.3 Rio Branco–Rupununi Savannas 85 4.4.3.1 Rio Branco Savannas 86 4.4.3.2 Rupununi Savannas 86 4.4.4 Savannas of Amapá 87 4.5 Southern Savannas 87 4.5.1 Savannas of Humaitá 87 4.5.2 Savannas of Pará 87 4.5.3 Beni Savannas 88 4.5.4 Cerrado 89 4.5.4.1 Cerrado (Sensu Stricto) 91 4.5.4.2 Cerrado Park 92 4.5.4.3 Palm Groves 92 4.5.4.4 Vereda 92 4.5.4.5 Campo Limpo (“Open Grassland”) 92 4.5.4.6 Campo Sujo (“Dense Grassland”) 92 4.5.4.7 Campo Rupestre (“Rocky Field”) 96 4.5.5 Pantanal 96 4.5.6 Chaco 97 4.6 Effects of Water Deficit, Herbivory, and Fire on Vegetation Dynamics 102 4.6.1 Water Deficit 102 4.6.2 Herbivory 103 4.6.3 Fire 104 4.7 Climate Change, Anthropogenic Pressure, and the Future 106 4.8 Concluding Remarks 109 4.9 Acknowledgments 109 References 110 5 Savannas of North America 123 Norma L. Fowler and Brian Beckage 5.1 Introduction 123 5.1.1 Definitions 123 5.1.2 Climatic Patterns 126 5.2 Fire 127 5.3 Grazing 128 5.4 Biodiversity 129 5.5 Conservation 129 5.6 Oak Savannas 130 5.6.1 Central US, South‐Central Canada, Northern Sierra Madre (Mexico) Oak Savannas 130 5.6.2 California Oak Savannas 132 5.6.3 South‐West (Arizona, New Mexico, Northern Mexico) Oak Savannas 132 5.6.4 Pacific Northwest Oak Savannas 132 5.6.5 East‐Central US: Glades, Barrens, and Other Forest Openings 132 5.6.6 Oak‐Dominated Shrub Savannas 133 5.7 Pine Savannas 133 5.7.1 South‐Eastern US Pine Savannas 133 5.7.2 Rocky Mountains Pine Savannas 134 5.8 Juniper Savannas 135 5.8.1 Juniper Savannas in the Western Mountains 135 5.8.2 Eastern Red Cedar Savannas 138 5.8.3 South‐Central US and Northern Sierra Madre Oriental Juniper Savannas 138 5.9 Mesquite Savannas 138 5.10 Northern and High‐Elevation Savannas 140 5.11 Shrub Savannas 140 5.12 Conclusions 141 5.13 Acknowledgments 141 References 141 6 Socioeconomic Value of Savannas 151 Wayne Twine 6.1 Introduction 151 6.2 Land Tenure and Land Use 153 6.3 Livestock Farming 155 6.3.1 Overview 155 6.3.2 Commercial Livestock Farming 157 6.3.3 Subsistence Livestock Farming 157 6.4 Wildlife Industry 159 6.4.1 Overview 159 6.4.2 Ecotourism 161 6.4.3 Hunting 162 6.4.4 Animal Products 163 6.4.5 Game Breeding and Live Sales 164 6.5 Commercial Timber 164 6.6 Non‐timber Products 164 6.6.1 Uses 164 6.6.2 Economic Value 166 6.6.2.1 Non‐monetary Income 166 6.6.2.2 Cash Income 167 6.6.2.3 Environmental Income 168 6.7 Conclusion 169 References 170 Part II Herbivores 181 7 Ecology of Smaller Animals Associated with Savanna Woody Plants: The Value of the Finer Details 183 Colleen Seymour and Grant Joseph 7.1 Introduction 183 7.2 Woody Plant Seed Herbivory 184 7.2.1 Seed Herbivores 184 7.3 Woody Plant Seed and Fruit Dispersal 187 7.3.1 Diplochory 187 7.3.1.1 Seed Dispersal by Birds 188 7.3.1.2 Invertebrate Seed Dispersal 189 7.3.2 Fruit Dispersal 189 7.4 Woody Plant Seedling Establishment 190 7.5 Leaves and Herbivory 191 7.6 Pollination and Nectarivory 193 7.7 Nutrient Cycling 195 7.8 Conclusions 199 References 201 8 Evolution of Large Mammal Herbivores in Savannas 213 Daryl Codron 8.1 Introduction 213 8.2 Herbivore Dietary Niches 215 8.3 Diversification of Browsers and Grazers 220 8.4 Effects of Vegetation Change 223 8.5 Herbivore Body Size 226 8.6 Pleistocene Extinctions and Contemporary Herbivore Diversity 228 8.7 Summary 233 References 234 9 Browser Population–Woody Vegetation Relationships in Savannas: From Bites to Landscapes 245 Melissa H. Schmitt and Adrian M. Shrader 9.1 Introduction 245 9.2 Factors Influencing Diet Selection 246 9.2.1 Browser Traits that Influence Foraging 247 9.2.1.1 Body Size 247 9.2.1.2 Gut Morphology 248 9.2.2 Woody Plant Traits that Influence Browsers 248 9.2.2.1 Seasonality 248 9.2.2.2 High Nutrient Levels (Positive) 249 9.2.2.3 Chemical Defenses (Negative) 250 9.2.2.4 Physical Defenses 252 9.2.2.5 Mutualisms 253 9.2.3 Herbivore Coping Mechanisms 253 9.3 Browser Impacts on Vegetation 255 9.3.1 Biomass Removal (Small and Large) 255 9.3.2 Impacts on Seeds 256 9.4 Feedback from Browsed Plants to Browsers 257 9.4.1 Lowered Food Availability 257 9.4.2 Habitat Changes 259 9.4.3 Change in Landscapes of Fear 260 9.4.4 New Growth 261 9.4.5 Nutrient Hot Spots 261 9.4.6 Browsing Lawns 261 9.5 Scaling from Bites to Browser Population Dynamics 262 9.5.1 Population Dynamics 263 9.5.2 Intake and Population Size 263 9.5.3 Food Availability, Food Quality, and Population Dynamics 264 9.5.4 Future Research 265 9.6 Conclusions 265 References 265 10 Predator Effects on Herbivore Dynamics and Behavior: What Mechanisms Lead to Trophic Cascades in Savannas? 279 Simon Chamaillé‐Jammes, Marion Valeix, and Joris Cromsigt 10.1 Introduction 279 10.2 Consumptive Effects of Predation 280 10.2.1 Concepts, Theory, and Evidence from Biomes Other than Savanna 280 10.2.1.1 Additive Versus Compensatory Mortality 281 10.2.1.2 Predator Functional Response 282 10.2.1.3 Ecosystem Characteristics 284 10.2.2 Evidence from Savannas 285 10.2.2.1 Additive Versus Compensatory Mortality 286 10.2.2.2 Predator Functional Response 288 10.2.2.3 Ecosystem Characteristics 288 10.3 Non‐consumptive Effects of Predation 290 10.3.1 Concepts, Theory, and Evidence from Biomes Other than Savanna 290 10.3.1.1 Landscape Use 290 10.3.1.2 Vigilance and Grouping Strategies 291 10.3.1.3 The Importance of Food–Safety Trade‐Offs 292 10.3.1.4 Demographic Costs of Behavioral Adjustments 293 10.3.2 Evidence from Savannas 293 10.3.2.1 Landscape Use 293 10.3.2.2 Vigilance and Grouping Strategies 295 10.4 Cascading Effects of Consumptive and Non‐consumptive Effects of Predation on Lower Trophic Levels 296 10.5 The Times they are A‐changin’: Changes in Megaherbivory, Migration Patterns, and Climate 297 References 299 Part III Woody Plants 309 11 Physiological Traits of Savanna Woody Species: Adaptations to Resource Availability 311 Edmund C. February, Corli Coetsee, Garry D. Cook, Jayashree Ratnam, and Benjamin Wigley 11.1 Introduction 311 11.2 Soil Nutrients and Root Responses 314 11.3 Leaf Phenology and Available Water 317 11.4 Competition for Resources 321 References 323 12 Patterns and Determinants of Woody Plant Growth in Savannas 331 Anthony Swemmer and David Ward 12.1 Introduction: The Relevance of Growth Rates 331 12.2 Determinants of Growth Rates 333 12.2.1 Seedlings 334 12.2.2 Saplings 342 12.2.3 Adults 344 12.2.4 Demographic Significance 344 12.2.4.1 Growth Trajectory 345 12.2.4.2 Size or Age of Individuals 345 12.2.4.3 Above vs Below Ground 345 12.2.4.4 Plant Part 347 12.2.4.5 Interacting Factors 347 12.2.4.6 Experimental Conditions 348 12.2.4.7 Individual vs Population Growth 348 12.2.4.8 Time and Size 348 12.2.4.9 Species 348 12.2.5 The Value of Long‐Term Research 349 12.3 Modeling Growth 350 12.3.1 Insights from Published Data 351 12.3.2 Predicting Rates from Environment or Phylogeny 353 12.3.3 Deficiencies in Growth Rate Data 356 12.4 Conclusions 357 12.A Appendix: Growth Rate Data 358 References 428 13 Fire and Browsers in Savannas: Traits, Interactions, and Continent‐Level Patterns 439 Gareth P. Hempson, Sally Archibald, and Carla Staver 13.1 Introduction 439 13.2 Browser and Fire Attributes 440 13.2.1 How do Fire and Browsers Compare as Consumers of Woody Plants? 440 13.2.1.1 Frequency and Seasonality 440 13.2.1.2 Selectivity, Intensity, and Scale 440 13.2.1.3 Elimination Thresholds 442 13.2.2 Plant Responses to Fire and Browsing 442 13.2.2.1 Defense Traits 442 13.2.2.2 Architecture 443 13.2.2.3 Resprouting and Bud Protection 444 13.2.2.4 Fire‐ and Browser‐Traps 445 13.2.2.5 Reproduction and Seedling Recruitment 446 13.3 Fire–Browser Interactions 447 13.3.1 Consequences of Fire for Browsers 447 13.3.1.1 Post‐Fire Environment 448 13.3.1.2 Woody Plant Regeneration 449 13.3.1.3 Decadal Fire Regimes 450 13.3.2 Browser Feedbacks to Fire 451 13.3.2.1 Browser Facilitation of Fire 451 13.3.2.2 Negative Feedbacks of Mixed‐Feeders 451 13.3.3 Fire–Browser Vegetation Impacts 452 13.3.3.1 Sapling Escape 452 13.3.3.2 Elephant Bark Stripping and Canopy Breakage 452 13.4 Biogeography of Fire and Browsing in Africa 453 13.4.1 Continental‐Scale Patterns of Fire and Browsing 455 13.4.2 Fire–Browser Regimes 457 13.4.3 Fine‐ vs Broad‐Leaved Savannas 457 13.5 Synthesis 460 References 460 14 Woody Plant Architecture and Effects on Browsing Herbivores in Savannas 469 Tristan Charles‐Dominique, Jean‐Francois Barczi , and Simon Chamaillé‐Jammes 14.1 Introduction 469 14.2 Factors Limiting Bite Size 471 14.3 Factors Limiting Biting Rate 474 14.4 Simulating Plant–Herbivore Interactions at the Individual Plant Scale 476 14.4.1 Plant Growth Model 477 14.4.2 Virtual Browsing and Consequences for Plant Fitness 478 14.4.3 Virtual Experiment Set‐up 478 14.4.4 Simulation Results 480 14.4.4.1 Effect of Leaf Size 481 14.4.4.2 Effect of Short Shoots 481 14.4.4.3 Effect of Spines 482 14.4.4.4 Effect of Cage Architecture 482 14.4.4.5 Effect of Short Shoot Induction 482 14.4.4.6 Effect of Sprouting 482 14.4.5 Significance of Simulation Results 482 14.5 Future Directions for Modeling Plant–Herbivore Interactions 483 Acknowledgments 483 14.A Appendix 484 References 484 15 Browsing Herbivore–Woody Plant Interactions in Savannas 489 Peter Frank Scogings and Juan H. Gowda 15.1 Introduction 489 15.1.1 The raison d’être 489 15.1.2 Approach 490 15.2 Feedback Between Woody Individuals and Browsing Herbivores 492 15.2.1 Shoot Growth 492 15.2.2 Spinescence 493 15.2.3 Nutrients and Phenolics 494 15.2.4 Is Positive Feedback Widespread? 495 15.3 Selective Browsing and Shifts in Woody Vegetation Composition and Structure 497 15.3.1 Recruitment and Mortality 497 15.3.2 Community Composition and Structure 500 15.4 Linking Responses of Woody Individuals and Communities to Functional Traits 501 15.5 Future Directions 504 15.5.1 Key Gaps 504 15.5.2 Standardizing Methods 505 References 539 16 Mesobrowser Abundance and Effects on Woody Plants in Savannas 551 David J. Augustine, Peter Frank Scogings, and Mahesh Sankaran 16.1 Introduction551 16.2 Mesobrowser Abundance in Savannas 552 16.3 Mesobrowser Diets in Savannas 559 16.4 Mesobrowser Effects on Woody Plant Communities 561 16.4.1 Hluhluwe‐iMfolozi Park, South Africa 564 16.4.2 Central Laikipia, Kenya 565 16.4.3 Chobe National Park, Botswana 567 16.4.4 Kruger National Park, South Africa 568 16.5 Evidence from Long‐Term Perspectives 569 16.6 The Influence of High Densities of Individual Mesobrowser Species 570 16.7 Water, Nutrients, and Mesobrowsers 571 16.8 Synthesis 573 Acknowledgments 576 References 576 17 Megabrowser Impacts on Woody Vegetation in Savannas 585 Norman Owen‐Smith, Bruce Page, Gabriella Teren, and Dave J. Druce 17.1 Introduction 585 17.2 Use of Woody Plants Versus Grasses and Other Plant Forms 586 17.3 Selection for Size Classes and Woody Plant Parts 589 17.4 Plant Damage Imposed and Mortality 590 17.5 Plant Species Selected 592 17.6 Landscape Transformations Caused by Elephants, Along with Fire 599 17.7 A Cautionary Note 602 17.8 Overview 602 References 604 18 Indirect Effects of Browsing Herbivores in Savannas 613 Corli Coetsee, Dario Fornara, Antoinette Veldtman, and Benjamin Wigley 18.1 Introduction 613 18.2 Indirect Effects of Browsers on Other Fauna 614 18.2.1 Mammals 614 18.2.1.1 Large Herbivore Effects on Rodents 614 18.2.1.2 Mesobrowser Effects on Other Herbivores 615 18.2.1.3 Megaherbivore Effects on Mesoherbivores 616 18.2.1.4 Interactions Among Browsers Where the Type of Browser is Not Apparent 616 18.2.1.5 Interactions Among Megaherbivores 617 18.2.1.6 Summary 617 18.2.2 Birds 617 18.2.2.1 Summary 619 18.2.3 Reptiles and Amphibians 619 18.2.3.1 Summary 619 18.2.4 Invertebrates 619 18.2.4.1 Summary 621 18.3 Effects on Ecosystem Processes 622 18.3.1 Carbon Cycling 622 18.3.1.1 Consumption of Vegetation by Browsers Affects Ecosystem Carbon Pools 622 18.3.1.2 Changes in Litterfall Affect Soil Carbon 625 18.3.1.3 Global Change Can Override the Effects of Herbivory on Soil Carbon 625 18.3.1.4 Summary 626 18.3.2 Soil Nutrient Cycling and Soil Nutrient Pools 626 18.3.2.1 Changes in Litter Quality 626 18.3.2.2 Herbivore Effects on both Litter Quality and Quantity 629 18.3.2.3 Summary 629 18.4 Conclusions 629 References 630 Part IV Synthesis 643 19 Water Limitation, Fire, and Savanna Persistence: A Conceptual Model 645 Brian Beckage, Gabriela Bucini, Louis J. Gross, William J. Platt, Steven I. Higgins, Norma L. Fowler, Matthew G. Slocum, and Caroline Farrior 19.1 Introduction 645 19.2 Conceptual Model 646 19.2.1 Water Limitation 648 19.2.2 Fire 650 19.2.3 Fire Feedbacks 651 19.2.4 Other Processes 652 19.3 Summary 653 Acknowledgments 654 References 654 20 Savanna Ecosystem Models: What Should a Clever Modeler Code? 661 Gregory Kiker and Peter Frank Scogings 20.1 Introduction 661 20.2 Local‐Scale Aspects of Woody Plant–Browser Interactions 662 20.3 Model Designs for Plant–Herbivore Interactions 663 20.3.1 Plant‐Focused Models 666 20.3.2 Herbivore‐Based Models 668 20.3.3 Integrated Models: Adding Complexity into Plant–Herbivore Models 670 20.4 Discussion 672 References 674 21 Woody Plants and Large Herbivores in Savannas: Ancient Past – Uncertain Future 683 Peter Frank Scogings and Mahesh Sankaran 21.1 Introduction 683 21.2 Woody Plants 685 21.3 Large Herbivores 688 21.4 Interactions Between Woody Plants and Browsers 690 21.4.1 Adaptations of Woody Plants to Browsing by Mesobrowsers 690 21.4.2 Woody Community Responses to Mesobrowsers and Megaherbivores 692 21.4.3 Indirect Effects of Browsing 696 21.5 Models 698 21.5.1 General Conceptual (Qualitative) Models 698 21.5.2 Mathematical (Quantitative) Models 700 21.6 The Future 701 References 703 Index 713

Autorenportrait

PETER FRANK SCOGINGS is Associate Professor, School of Life Sciences, University of KwaZulu-Natal, South Africa. MAHESH SANKARAN is Reader, National Centre for Biological Sciences, India, and Lecturer, Institute of Integrative & Comparative Biology, Faculty of Biological Sciences, University of Leeds, UK.

Back cover copy

Insights on current research and recent developments in understanding global savanna systems Increasingly recognized as synonymous with tropical grassy biomes, savannas are found in tropical and sub-tropical climates as well as warm, temperate regions of North America. Savanna Woody Plants and Large Herbivores examines the interactions between woody plants and browsing mammals in global savannas—focusing primarily on the C4 grassy ecosystems with woody components that constitute the majority of global savannas—and discusses contemporary savanna management models and applications. This much-needed addition to current research examines topics including the varying behavior of browsing mammals, the response to browsing by woody species, and the factors that inhibit forage intake. Contributions from an international team of active researchers and experts compare and contrast different savanna ecosystems, offering a global perspective on savanna functioning, the roles of soil and climate in resource availability and organism interaction, and the possible impacts of climate change across global savannas. <ul> <li>Fills a gap in literature on savanna management issues, including biodiversity conservation and animal production</li> <li>Applies concepts developed in other biomes to future savanna research</li> <li>Complements contemporary books on savanna or large herbivore ecology</li> <li>Focuses on the woody component of savanna ecosystems and large herbivore interactions in savannas</li> <li>Compares tree-mammal systems of savannas and other eco-systems of temperate and boreal regions</li> <li>Provides numerous case studies of plant-mammal interactions from various savanna ecosystems</li> </ul> Savanna Woody Plants and Large Herbivores is a valuable addition to those in fields such as ecology, wildlife and conservation biology, natural resource management, and environmental science.