Resolving Ecosystem Complexity

An ecosystem's complexity develops from the vast numbers of species interacting in ecological communities. The nature of these interactions, in turn, depends on environmental context. How do these components together influence an ecosystem's behavior as a whole? Can ecologists resolve an ecosystem's complexity in order to predict its response to disturbances? "Resolving Ecosystem Complexity" develops a framework for anticipating the ways environmental context determines the functioning of ecosystems. Oswald Schmitz addresses the critical questions of contemporary ecology: How should an ecosystem be conceptualized to blend its biotic and biophysical components? How should evolutionary ecological principles be used to derive an operational understanding of complex, adaptive ecosystems? How should the relationship between the functional biotic diversity of ecosystems and their properties be understood? Schmitz begins with the universal concept that ecosystems are comprised of species that consume resources and which are then resources for other consumers. From this, he deduces a fundamental rule or evolutionary ecological mechanism for explaining context dependency: individuals within a species trade off foraging gains against the risk of being consumed by predators. Through empirical examples, Schmitz illustrates how species use evolutionary ecological strategies to negotiate a predator-eat-predator world, and he suggests that the implications of species trade-offs are critical to making ecology a predictive science. Bridging the traditional divides between individuals, populations, and communities in ecology, "Resolving Ecosystem Complexity" builds a systematic foundation for thinking about natural systems.

Table of Contents:
List of Illustrations ix List of Tables xiii Preface xv Chapter 1: Introduction 1 Philosophical Musings 2 Explaining Contingency: A Worldview 4 Contingency and Emergence 5 Preparing the Mind for Discovery 7 Structure of the Book 8 Chapter 2: Conceptualizing Ecosystem Structure 10 Abstracting Complexity 11 Whole System vs. Building Blocks Approach 13 Defining Species Interaction Modules 15 Identifying Interaction Modules in a Grassland Ecosystem 16 Conception of Ecosystem Structure 20 Chapter 3: Trophic Dynamics: Why Is the World Green? 23 Trophic Control as an Emergent Property of Resource Limitation 24 Explaining Contingency in Trophic Control of Ecosystem Function 26 The Nature of Resource Limitation and Trophic Control of Food Chains 28 The Mechanism Switching Hypothesis of Trophic Control 32 Effects of Herbivore Feeding Mode 36 Collective Effects of Herbivore Species with Different Feeding Modes 38 Plant- Antiherbivore Defense and Strength of Trophic Control 39 Herbivore Resource Selection and Ecosystem Function 41 Stoichiometry and Herbivore Resource Use 42 Resource Selection and Ecosystem Function 43 Herbivore Indirect Effects and Engineering of Green Worlds 46 Herbivore- Mediated Carnivore Indirect Effects on Ecosystems 47 Carnivore Indirect Effects on Plant Diversity 47 Carnivore Indirect Effects on Ecosystem Function 50 Chapter 4: The Green World and the Brown Chain 55 Conceptualizing Functions along Detritus- Based Chains 56 Resource Limitation and Trophic Control 57 Trophic Control of Decomposition 59 Trophic Control of Mineralization 61 Mechanisms of Top- Down Control 62 Trophic Coupling between Detritus- Based and Plant- Based Chains 64 Chapter 5: The Evolutionary Ecology of Trophic Control in Ecosystems 68 Carnivore Species and the Nature of Trophic Interactions in an Old- Field System 69 Carnivore Hunting Mode and the Nature of Trophic Interactions 74 The Evolutionary Ecology of Trophic Cascades 86 Chapter 6: The Whole and the Parts 99 Developing Predictive Theory for Emergence 100 Contingency and Carnivore Diversity Effects on Ecosystems 101 Carnivore Diversity and Emergent Effects on Ecosystem Function 106 Shifting Down One Trophic Level: Intermediate Species Diversity and Ecosystem Function 110 Herbivore Diversity and Mediation of Top- Down Control of Ecosystem Function 112 Detritivore Diversity and Mediation of Top- Down Control of Ecosystem Function 117 The Basal Trophic Level: Plant Diversity and Ecosystem Function 118 Functional Classifications 119 Resource Identity Effects on Trophic Interactions 121 Moving Forward on Functional Diversity and Ecosystem Function 122 Chapter 7: The Ecological Theater and the Evolutionary Ecological Play 125 Phenotypic Variation and State- Dependent Trade- Offs 127 Attacked Plants Attract Predators 129 Predators That Avoid Predation 130 The Nonconsumptive Basis of Trophic Transfer Efficiencies 132 Trophic Interactions in a Changing Theater 133 Rapid Change in Hunting Strategy 135 Landscapes of Fear and Ecosystem Management 135 Closing Remarks 139 References 143 Index 167