Essentials of Ecology (Third Edition)

523 Pages·2008·34.7 MB·English

by  Colin R. Townsend

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ESSENTIALS
OF ECOLOGY
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ESSENTIALS
OF ECOLOGY
Third Edition
Colin R. Townsend
Department of Zoology, University of Otago, Dunedin, New Zealand

Michael Begon
Population Biology Research Group, School of Biological Sciences
The University of Liverpool, Liverpool, UK
John L. Harper
Professor Emeritus in the University of Wales
Visiting Professor in the University of Exeter, Exeter, UK
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© 2008 by Blackwell Publishing
BLACKWELL PUBLISHING
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The right of Colin R. Townsend, Michael Begon, and John L. Harper to be identified as the
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the services of a competent professional should be sought.
First edition published 2000 by Blackwell Publishing
Second edition published 2003
Third edition published 2008
1 2008
Library of Congress Cataloging-in-Publication Data
Townsend, Colin R.
Essentials of ecology / Colin R. Townsend, Michael Begon, John L. Harper.—3rd ed.
p. cm.
Includes bibliographical references and index.
ISBN 978-1-4051-5658-5 (pbk. : alk. paper)
1. Ecology. I. Begon, Michael. II. Harper, John L. III. Title.
QH541.T66 2008
577—dc22 2007034694
A catalogue record for this title is available from the British Library.
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Short contents
SHORT CONTENTS
Full contents vi
Preface x
Acknowledgments xii
Part I Introduction
1
1 Ecology and how to do it 3
2 Ecology’s evolutionary backdrop 36
Part II Conditions and Resources
67
3 Physical conditions and the availability of resources 69
4 Conditions, resources and the world’s communities 110
Part III Individuals, Populations, Communities and Ecosystems
143
5 Birth, death and movement 145
6 Interspecific competition 182
7 Predation, grazing and disease 217
8 Evolutionary ecology 251
9 From populations to communities 281
10 Patterns in species richness 323
11 The flux of energy and matter through ecosystems 357

Part IV Applied Issues in Ecology
387
12 Sustainability 389
13 Habitat degradation 423
14 Conservation 455
References 483
Index 495
v
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CONTENTS
Preface x
Acknowledgments xii
Part I Introduction
1
1 Ecology and how to do it
3
1.1 Introduction 4
1.2 Scales, diversity and rigor 7
1.3 Ecology in practice 17
2 Ecology’s evolutionary backdrop
36
2.1 Introduction 37
2.2 Evolution by natural selection 37
2.3 Evolution within species 41
2.4 The ecology of speciation 51
2.5 Effects of climatic change on the evolution and distribution of species 58
2.6 Effects of continental drift on the ecology of evolution 60
2.7 Interpreting the results of evolution: convergents and parallels 63

Part II Conditions and Resources
67
3 Physical conditions and the availability
of resources
69
3.1 Introduction 70
3.2 Environmental conditions 71
3.3 Plant resources 84
3.4 Animals and their resources 95
3.5 Effects of intraspecific competition for resources 103
3.6 Conditions, resources and the ecological niche 106
vi
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Contents vii
4 Conditions, resources and the world’s
communities
110
4.1 Introduction 111
4.2 Geographic patterns at large and small scales 111
4.3 Temporal patterns in conditions and resources 117
4.4 Terrestrial biomes 119
4.5 Aquatic environments 130
Part III Individuals, Populations,
Communities and Ecosystems
143
5 Birth, death and movement
145
5.1 Introduction 146
5.2 Life cycles 151
5.3 Monitoring birth and death: life tables and fecundity schedules 156
5.4 Dispersal and migration 164
5.5 The impact of intraspecific competition on populations 169
5.6 Life history patterns 175
6 Interspecific competition
182
6.1 Introduction 183
6.2 Ecological effects of interspecific competition 183
6.3 Evolutionary effects of interspecific competition 197
6.4 Interspecific competition and community structure 200
6.5 How significant is interspecific competition in practice? 208
7 Predation, grazing and disease
217
7.1 Introduction 218
7.2 Prey fitness and abundance 220
7.3 The subtleties of predation 222
7.4 Predator behavior: foraging and transmission 228
7.5 Population dynamics of predation 233
7.6 Predation and community structure 246
8 Evolutionary ecology
251
8.1 Introduction 252
8.2 Molecular ecology: differentiation within and between species 253
8.3 Coevolutionary arms races 262
8.4 Mutualistic interactions 267
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viii Contents
9 From populations to communities
281
9.1 Introduction 282
9.2 Multiple determinants of the dynamics of populations 283
9.3 Dispersal, patches and metapopulation dynamics 294
9.4 Temporal patterns in community composition 299
9.5 Food webs 307
10 Patterns in species richness
323
10.1 Introduction 324
10.2 A simple model of species richness 326
10.3 Spatially varying factors that influence species richness 328
10.4 Temporally varying factors that influence species richness 337
10.5 Gradients of species richness 340
10.6 Patterns in taxon richness in the fossil record 349
10.7 Appraisal of patterns in species richness 352
11 The flux of energy and matter through ecosystems
357
11.1 Introduction 358
11.2 Primary productivity 360
11.3 The fate of primary productivity 364
11.4 The process of decomposition 369
11.5 The flux of matter through ecosystems 374
11.6 Global biogeochemical cycles 380
Part IV Applied Issues in Ecology
387
12 Sustainability
389
12.1 Introduction 390

12.2 The human population ‘problem’ 391
12.3 Harvesting living resources from the wild 399
12.4 The farming of monocultures 405
12.5 Pest control 412
12.6 Integrated farming systems 417
12.7 Forecasting agriculturally driven global environmental change 419
13 Habitat degradation
423
13.1 Introduction 424
13.2 Degradation via cultivation 428
13.3 Power generation and its diverse effects 435
13.4 Degradation in urban and industrial landscapes 442
13.5 Maintenance and restoration of ecosystem services 448
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Contents ix
14 Conservation
455
14.1 Introduction 456
14.2 Threats to biodiversity 459
14.3 Conservation in practice 468
14.4 Conservation in a changing world 476
14.5 Finale 479
References 483
Index 495