F.Stuart Chapin III Pamela A.Matson Harold A.Mooney Principles of Terrestrial Ecosystem Ecology Illustrated by Melissa C.Chapin With 199 Illustrations Springer
F. Stuart Chapin III Pamela A. Matson Harold A. Mooney Principles of Terrestrial Ecosystem Ecology Illustrated by Melissa C. Chapin With 199 Illustrations 1 3
Preface Human activities are affecting the global environment in myriad ways,with numerous direct and indirect effects on ecosystems. The climate and atmospheric composition of Earth are changing rapidly.Humans have directly modified ha ol the ice-free terres use 0%of terrestrial produc Our ac r ex th vent in the :f history of hte on fields trean tte toprovide their sensitivit to on ng and biotic cha We believe that an understanding of how ecosystems erate and change must t itoduce the of ye ecology to advanced undergraduate students,beginning graduate students,and practicing scientists from a wide array of disciplines. We also provide access to some of the rapidly expanding literature in the many disciplines that contribute to ecosystem understanding. The first part of the book provides the context for understand ing ecosystem ecology.We introduce the science of ecosystem rt sho osphere,ocean,cl systems and contribute to the ecosystem str th nd fo the fows by nd nd thst carbon and nutrients.We then co are and contrast these between terrestrial and aquatic e systems.We also consider th important role that organisms have on ecosystem tal effects,and disturbance.The third part of the book addresses temporal and spatial patterns in ecosystem processes.We finish by considering the integrated effects of these processes at the global scale and their consequences for sustainable use by human soci-
Human activities are affecting the global environment in myriad ways, with numerous direct and indirect effects on ecosystems. The climate and atmospheric composition of Earth are changing rapidly. Humans have directly modified half of the ice-free terrestrial surface and use 40% of terrestrial production. Our actions are causing the sixth major extinction event in the history of life on Earth and are radically modifying the interactions among forests, fields, streams, and oceans. This book was written to provide a conceptual basis for understanding terrestrial ecosystem processes and their sensitivity to environmental and biotic changes. We believe that an understanding of how ecosystems operate and change must underlie our analysis of both the consequences and the mitigation of human-caused changes. This book is intended to introduce the science of ecosystem ecology to advanced undergraduate students, beginning graduate students, and practicing scientists from a wide array of disciplines. We also provide access to some of the rapidly expanding literature in the many disciplines that contribute to ecosystem understanding. The first part of the book provides the context for understanding ecosystem ecology. We introduce the science of ecosystem ecology and place it in the context of other components of the Earth System—the atmosphere, ocean, climate and geological systems. We show how these components affect ecosystem processes and contribute to the global variation in terrestrial ecosystem structure and processes. In the second part of the book, we consider the mechanisms by which terrestrial ecosystems function and focus on the flow of water and energy and the cycling of carbon and nutrients. We then compare and contrast these cycles between terrestrial and aquatic ecosystems. We also consider the important role that organisms have on ecosystem processes through trophic interactions (feeding relationships), environmental effects, and disturbance. The third part of the book addresses temporal and spatial patterns in ecosystem processes. We finish by considering the integrated effects of these processes at the global scale and their consequences for sustainable use by human sociPreface v
vi Preface eties.Powerpoint lecture notes developed by one of the authors are available online(www.faculty.uafedu/fffsc/)as supplementary material. Many people have contributed to the development of this book. We particularly thank our families,whose patience has made the book possible,and our students from whom we have learned many of the important ideas that are presented.In addition,we thank the following individuals for their constructively critical review of chapters in this book:Kevin Arrigo,Teri Balser,Perry Barboza. Beringer. Bonine Cham ryan Rich Boone e h az.Bitha olf- im hmer.Ste Val Scott Fendorf.Jon Folev.David Fo man.Paul Grogan.Diego Gurvich.Bill Heal.Sarah Hobbie.Dave Hooper.Shuijin Hu.Pilar Huante.Bruce Hunga Jay jones,Jurg Luterbacher,Frank Kelliher,Jennifer King. Dave Kline christian korner Hans iambers amanda iynch michelle Mack,Steve MacLean,Joe McFadden,Dave McGuire,Sam MeNaughton,Knute Nadelhoffer,Jason Neff,Mark Oswood,Bob Paine.Bill Parton.Natalia Perez.Steward Pickett.Stephen Parder. Mary Power,Jim Randerson,Bill Reeburgh,Peter Reich,Jim Reynolds,Roger Ruess.Steve Running.Scott Rupp,Dave Schimel Josh Schimel Bill Schlesinger,Guthrie Schrengohst,Ted Schuur. Stephen Parde Serreze,Gus Shaver,Ni ave alentine larly thank Phil C rogan ark Ch ck Endres,an d Ro cnes:a maps E Start Chapin Pamela A.Matson Harold A.Mooney
vi Preface eties. Powerpoint lecture notes developed by one of the authors are available online (www.faculty.uaf.edu/fffsc/) as supplementary material. Many people have contributed to the development of this book. We particularly thank our families, whose patience has made the book possible, and our students from whom we have learned many of the important ideas that are presented. In addition, we thank the following individuals for their constructively critical review of chapters in this book: Kevin Arrigo, Teri Balser, Perry Barboza, Jason Beringer, Kim Bonine, Rich Boone, Syndonia Bret-Harte, John Bryant, Inde Burke, Zoe Cardon, Oliver Chadwick, Scott Chambers, Melissa Chapin, Kathy Cottingham, Joe Craine, Wolfgang Cramer, Steve Davis, Sandra Diaz, Bill Dietrich, Rob Dunbar, Jim Ehleringer, Howie Epstein, Werner Eugster, Valerie Eviner, Scott Fendorf, Jon Foley, David Foster, Tom Gower, Peter Groffman, Paul Grogan, Diego Gurvich, Bill Heal, Sarah Hobbie, Dave Hooper, Shuijin Hu, Pilar Huante, Bruce Hungate, Jill Johnstone, Jay Jones, Jürg Luterbacher, Frank Kelliher, Jennifer King, Dave Kline, Christian Körner, Hans Lambers, Amanda Lynch, Michelle Mack, Steve MacLean, Joe McFadden, Dave McGuire, Sam McNaughton, Knute Nadelhoffer, Jason Neff, Mark Oswood, Bob Paine, Bill Parton, Natalia Perez, Steward Pickett, Stephen Parder, Mary Power, Jim Randerson, Bill Reeburgh, Peter Reich, Jim Reynolds, Roger Ruess, Steve Running, Scott Rupp, Dave Schimel, Josh Schimel, Bill Schlesinger, Guthrie Schrengohst, Ted Schuur, Stephen Parder Mark Serreze, Gus Shaver, Nigel Tapper, Monica Turner, Dave Valentine, Peter Vitousek, Lars Walker, and Katey Walter.We particularly thank Phil Camil,Valerie Eviner, Jon Foley, and Paul Grogan for comments on the entire book; Mark Chapin, Patrick Endres, and Rose Meier for comments on illustrations; Phil Camil for comments on educational approaches; and Jon Foley and Nick Olejniczak for providing global maps. F. Stuart Chapin III Pamela A. Matson Harold A. Mooney
Contents Preface........... Part I Context 。 2 of E Ecosystem Structure o Controls over Ecosystem Processes Human-Caused Changes in Earth's Ecosystems Summary 1 Review ouestions 11 Additional Reading............................. 17 Chapter2 Earth's Climate System 8811248 Ocean structur Landform Effects on Climate 31 Vegetation Influences on Climate Temporal Variability in Climate Long-Term Changes. Interannual Climate Variability Seasonal and Daily Variations 40
Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v Part I Context Chapter 1 The Ecosystem Concept Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Overview of Ecosystem Ecology . . . . . . . . . . . . . . . . . . . 3 History of Ecosystem Ecology . . . . . . . . . . . . . . . . . . . . . 7 Ecosystem Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Controls over Ecosystem Processes . . . . . . . . . . . . . . . . . 11 Human-Caused Changes in Earth’s Ecosystems . . . . . . . 13 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Chapter 2 Earth’s Climate System Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Earth’s Energy Budget . . . . . . . . . . . . . . . . . . . . . . . . . . 18 The Atmospheric System . . . . . . . . . . . . . . . . . . . . . . . . . 21 Atmospheric Composition and Chemistry . . . . . . . . . . 21 Atmospheric Structure . . . . . . . . . . . . . . . . . . . . . . . . . 22 Atmospheric Circulation . . . . . . . . . . . . . . . . . . . . . . . 24 The Oceans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Ocean Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Ocean Circulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Landform Effects on Climate . . . . . . . . . . . . . . . . . . . . . 31 Vegetation Influences on Climate . . . . . . . . . . . . . . . . . . 32 Temporal Variability in Climate . . . . . . . . . . . . . . . . . . . . 34 Long-Term Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Interannual Climate Variability . . . . . . . . . . . . . . . . . . 38 Seasonal and Daily Variations . . . . . . . . . . . . . . . . . . . 40 vii
viii Contents Relationship of climate to ecosystem distribution and Structure 41 Summary Review ouestions Additional Reading 45 Chapter 3 Geology and Soils Introduction 。。。。。。。。。。。。 Soil Formation 48 pography Human activities Controls over Soil Loss 5 Development of Soil Profiles Additions to Soils Soil Transformations Soil Transfers Losses from Soils Soil Horizons and Soil Classification Soil Properties and Ecosystem Functioning 586656 Additional Reading PartⅡMechanisms Chanter 4 Terrestrial Water and Energy Balance Introduction Surface eneroy balance Solar Radiation Budget 73 Ecosystem Radiation Budget Energy Partitioning Seasonal Energy Exchange Water Inputs to Ecosystems Water Movements Within Ecosystems Basic Principles of Water Movement rom the Canopy to the Soil vement 777908 om S hrough Plants 05 89 Wet C vapotranspiration from Dry Ev porat nopies
viii Contents Relationship of Climate to Ecosystem Distribution and Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Chapter 3 Geology and Soils Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Controls over Soil Formation . . . . . . . . . . . . . . . . . . . . . 46 Parent Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Topography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Potential Biota . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Human Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Controls over Soil Loss . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Development of Soil Profiles . . . . . . . . . . . . . . . . . . . . . . 53 Additions to Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Soil Transformations . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Soil Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Losses from Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Soil Horizons and Soil Classification . . . . . . . . . . . . . . . . 58 Soil Properties and Ecosystem Functioning . . . . . . . . . . 61 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Part II Mechanisms Chapter 4 Terrestrial Water and Energy Balance Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Surface Energy Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Solar Radiation Budget . . . . . . . . . . . . . . . . . . . . . . . . 73 Ecosystem Radiation Budget . . . . . . . . . . . . . . . . . . . . 74 Energy Partitioning . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Seasonal Energy Exchange . . . . . . . . . . . . . . . . . . . . . 77 Water Inputs to Ecosystems . . . . . . . . . . . . . . . . . . . . . . 77 Water Movements Within Ecosystems . . . . . . . . . . . . . . . 78 Basic Principles of Water Movement . . . . . . . . . . . . . . 78 Water Movement from the Canopy to the Soil . . . . . . 79 Water Movement Within the Soil . . . . . . . . . . . . . . . . . 80 Water Movement from Soil to Roots . . . . . . . . . . . . . . 81 Water Movement Through Plants . . . . . . . . . . . . . . . . 83 Water Losses from Ecosystems . . . . . . . . . . . . . . . . . . . . 89 Evaporation from Wet Canopies . . . . . . . . . . . . . . . . . 89 Evapotranspiration from Dry Canopies . . . . . . . . . . . . 90
Contents ix Changes in Storage. Runof R Additi ding Input to Terrestrial Ecosystems Introduction Photosynthetic Pathways C,Photosynthesis C.Photosynthesis 102 Crassulacean Acid Metabolism Photosynthesis 103 Net Photosynthesis by Individual Leaves 105 Basic Principle of Environmental Control.......... 105 Light Limitation Capudioy ure 12 Gr .D Canopy Pro 115 s of GPP 117 Controls over GPP 119 Summary 121 Review ouestions 121 Additional Reading 122 Chapter6 Terrestrial Production processes Introduction 。。。。。。。。。 123 Overview 123 Basis of Respiration What Is NPR? Phys over NPP mental Controls over NPP 132 Allocation of NPP 132 Allocation res onse to Multiple Resources 133 Diurnal and Seasonal Cycles of Allocation 134 Tissue Turnover 136 Global Distribution of Biomass and NPP 137 Biome Differences in Biomass ... 137 Biome Differences in NPP 138 Net Ecosystem Production 140
Contents ix Changes in Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Runoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 Chapter 5 Carbon Input to Terrestrial Ecosystems Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Photosynthetic Pathways . . . . . . . . . . . . . . . . . . . . . . . . . 98 C3 Photosynthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 C4 Photosynthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 Crassulacean Acid Metabolism Photosynthesis . . . . . . 103 Net Photosynthesis by Individual Leaves . . . . . . . . . . . . 105 Basic Principle of Environmental Control . . . . . . . . . . 105 Light Limitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 CO2 Limitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 Nitrogen Limitation and Photosynthetic Capacity . . . . 110 Water Limitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Temperature Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Pollutants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Gross Primary Production . . . . . . . . . . . . . . . . . . . . . . . . 115 Canopy Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Satellite Estimates of GPP . . . . . . . . . . . . . . . . . . . . . . 117 Controls over GPP . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 Chapter 6 Terrestrial Production Processes Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Plant Respiration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Physiological Basis of Respiration . . . . . . . . . . . . . . . . 125 Net Primary Production . . . . . . . . . . . . . . . . . . . . . . . . . . 127 What Is NPP? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Physiological Controls over NPP . . . . . . . . . . . . . . . . . 128 Environmental Controls over NPP . . . . . . . . . . . . . . . 129 Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 Allocation of NPP . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 Allocation Response to Multiple Resources . . . . . . . . 133 Diurnal and Seasonal Cycles of Allocation . . . . . . . . . 134 Tissue Turnover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Global Distribution of Biomass and NPP . . . . . . . . . . . . 137 Biome Differences in Biomass . . . . . . . . . . . . . . . . . . . 137 Biome Differences in NPP . . . . . . . . . . . . . . . . . . . . . . 138 Net Ecosystem Production . . . . . . . . . . . . . . . . . . . . . . . 140
x Contents Ecosystem Carbon Storage 140 L eaching 141 Lateral Transfers 145 Disturbance Controls over Net Ecosystem Production 145 Net Ecosystem Exchange ...................... 146 Global Patterns of NEE........................ Summary 。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。 148 Review Questions 149 Additional Reading 149 Chapter 7 Terrestrial Decomposition Introduction 151 Leaching of Litter 152 litter fragmentation Chemical Alteration 152 Fungi 153 Bacteria 154 Soil Animals 155 Temporal and Spatial Heterogeneity of Decomposition 157 lemporal Pattern 157 Spatial Patterr Factors Controlling Decomposition The Physical Quantity 996 Compos ion and Dong-Term at the Ec ic Matter ophic res 8600 Anaerobic Heterotrophic Respiration Summary 174 Review ouestions 174 Additional Reading 175 Chapter 8 Terrestrial Plant Nutrient Use Introduction 176 Overview Nutrient Movement to the Root 79 Flow De Root Length 181 182
x Contents Ecosystem Carbon Storage . . . . . . . . . . . . . . . . . . . . . 140 Leaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 Lateral Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 Disturbance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 Controls over Net Ecosystem Production . . . . . . . . . . 145 Net Ecosystem Exchange . . . . . . . . . . . . . . . . . . . . . . . 146 Global Patterns of NEE . . . . . . . . . . . . . . . . . . . . . . . . 147 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 Chapter 7 Terrestrial Decomposition Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 Leaching of Litter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 Litter Fragmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 Chemical Alteration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 Fungi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 Bacteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 Soil Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 Temporal and Spatial Heterogeneity of Decomposition . 157 Temporal Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 Spatial Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 Factors Controlling Decomposition . . . . . . . . . . . . . . . . . 159 The Physical Environment . . . . . . . . . . . . . . . . . . . . . . 159 Substrate Quality and Quantity . . . . . . . . . . . . . . . . . . 163 Microbial Community Composition and Enzymatic Capacity . . . . . . . . . . . . . . . . . . . . . . . . . 168 Long-Term Storage of Soil Organic Matter . . . . . . . . . . . 169 Decomposition at the Ecosystem Scale . . . . . . . . . . . . . . 170 Aerobic Heterotrophic Respiration . . . . . . . . . . . . . . . 170 Anaerobic Heterotrophic Respiration . . . . . . . . . . . . . 173 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 Chapter 8 Terrestrial Plant Nutrient Use Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 Nutrient Movement to the Root . . . . . . . . . . . . . . . . . . . 177 Diffusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 Mass Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 Root Interception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 Nutrient Uptake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 Nutrient Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 Development of Root Length . . . . . . . . . . . . . . . . . . . 181 Mycorrhizae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
Contents xi Root Uptake Properties 184 192 Ioss from Plant 193 193 Other Avenues of Nutrient Loss from Plants A Summar 194 Review Questions 195 Additional Reading 195 Chapter 9 Terrestrial Nutrient Cycling Introduction.......... Overview Nitrogen Inpu s to Eco ysten s tr Inte nd Fat of D soed Organi Nitr 203 Production and Fate of Ammonium 204 Production and fate of nitrat 207 Temporal and Spatial Variability 10 Pathways of nitrogen i oss 211 Gaseous Losses of Nitrogen 211 Ecological Controls 211 Solution Losses 214 Erosional Losses 215 Other Element Cycles Phosphorus...... Sulfur Essential Cations Nonessential Element Interactions Among Element Cycles 0 22 Questions Additional Readin 223 Aquatic Carbon and Nutrient Cycling Introduction 224 Ecosystem Properties. 224 Oceans. 228 Carbon and Light Availability.................. 228 Nutrient Availability ..... 231 Carbon and Nutrient Cycling.................... Lakes Controls over NPP
Contents xi Root Uptake Properties . . . . . . . . . . . . . . . . . . . . . . . . 184 Nutrient Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189 Nutrient Loss from Plants . . . . . . . . . . . . . . . . . . . . . . . . 191 Senescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 Leaching Loss from Plants . . . . . . . . . . . . . . . . . . . . . . 193 Herbivory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 Other Avenues of Nutrient Loss from Plants . . . . . . . 194 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Chapter 9 Terrestrial Nutrient Cycling Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Nitrogen Inputs to Ecosystems . . . . . . . . . . . . . . . . . . . . 198 Biological Nitrogen Fixation . . . . . . . . . . . . . . . . . . . . 198 Nitrogen Deposition . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 Internal Cycling of Nitrogen . . . . . . . . . . . . . . . . . . . . . . 202 Overview of Mineralization . . . . . . . . . . . . . . . . . . . . . 202 Production and Fate of Dissolved Organic Nitrogen . . 203 Production and Fate of Ammonium . . . . . . . . . . . . . . . 204 Production and Fate of Nitrate . . . . . . . . . . . . . . . . . . 207 Temporal and Spatial Variability . . . . . . . . . . . . . . . . . 210 Pathways of Nitrogen Loss . . . . . . . . . . . . . . . . . . . . . . . 211 Gaseous Losses of Nitrogen . . . . . . . . . . . . . . . . . . . . . 211 Ecological Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 Solution Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 Erosional Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 Other Element Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 Phosphorus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 Sulfur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 Essential Cations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 Nonessential Elements . . . . . . . . . . . . . . . . . . . . . . . . . 220 Interactions Among Element Cycles . . . . . . . . . . . . . . 220 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 Chapter 10 Aquatic Carbon and Nutrient Cycling Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 Ecosystem Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 Oceans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 Carbon and Light Availability . . . . . . . . . . . . . . . . . . . 228 Nutrient Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 Carbon and Nutrient Cycling . . . . . . . . . . . . . . . . . . . . 233 Lakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 Controls over NPP . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
xii Contents Carbon and nutrient cycling 238 Streams and Rivers 238 Carbon and Nutrient Cycling 240 Summary 242 Review Questions ............................. 242 Additional Reading............................. 243 Chapter 11 Trophic Dynamics Introduction 244 244 Plant-Ba sed Tr phic Systems 246 Controls over Ener 246 Ecological Efficien y Flow Through Ecosystems 250 Food Chain Length and Trophic Cascades 25 Seasonal Patterns 258 Nutrient transfers 259 Detritus-Based Trophic Systems 261 Integrated Food Webs 261 Mixing of Plant-Based and Detritus-Based Food Chains Food Web Complexities Summary RaioOReihe Community Effects on Ecosystem Processes Introduction 265 Overview 266 Species Effects on Ecosystem Processes 268 Species Effects on Resources Species Effects on Climate 271 Species Effects on Disturbance Regime 272 Species Interactions and Ecosystem Processes........ 273 Diversity Effects on Ecosystem Processes............ Remmary 274 Part III Patterns Chapter 13 Temporal Dynamics atrodlcion in E I Variability 281 Long-Term Cha ange
xii Contents Carbon and Nutrient Cycling . . . . . . . . . . . . . . . . . . . . 238 Streams and Rivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 Carbon and Nutrient Cycling . . . . . . . . . . . . . . . . . . . . 240 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243 Chapter 11 Trophic Dynamics Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244 Plant-Based Trophic Systems . . . . . . . . . . . . . . . . . . . . . . 246 Controls over Energy Flow Through Ecosystems . . . . 246 Ecological Efficiencies . . . . . . . . . . . . . . . . . . . . . . . . . 250 Food Chain Length and Trophic Cascades . . . . . . . . . . 257 Seasonal Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Nutrient Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 Detritus-Based Trophic Systems . . . . . . . . . . . . . . . . . . . 261 Integrated Food Webs . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 Mixing of Plant-Based and Detritus-Based Food Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 Food Web Complexities . . . . . . . . . . . . . . . . . . . . . . . . 263 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 Chapter 12 Community Effects on Ecosystem Processes Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 Species Effects on Ecosystem Processes . . . . . . . . . . . . . 268 Species Effects on Resources . . . . . . . . . . . . . . . . . . . . 268 Species Effects on Climate . . . . . . . . . . . . . . . . . . . . . . 271 Species Effects on Disturbance Regime . . . . . . . . . . . 272 Species Interactions and Ecosystem Processes . . . . . . . . 273 Diversity Effects on Ecosystem Processes . . . . . . . . . . . . 274 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Part III Patterns Chapter 13 Temporal Dynamics Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281 Fluctuations in Ecosystem Processes . . . . . . . . . . . . . . . . 281 Interannual Variability . . . . . . . . . . . . . . . . . . . . . . . . . 281 Long-Term Change . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Contents xiii Disturbance 285 ance Properties Su Structureand Composition 292 rient Cycling 296 298 Water and energy exchange 200 Temporal Scaling of Ecological Processes 301 Summary 302 Review Ouestions 303 Additional Reading 304 Chapter 14 Landscape Heterogeneity and Ecosystem Dynamics Introduction 305 Concepts of L roger and Intera ontrols............. f Heterogeneity 311 Patch Interaction 31 hic and Land-Water Interactions 314 317 Movement of Plants and Animals on the I andscane 320 Disturbance spread 320 Human Land Use Change and Landscape Heterogeneity.,.· Extensification 321 Intensincation . 。。。。。。。。。。。。。。。 Spatial Heterogeneity and Scaling.................. Summary... Review Questio Additional Reading Part IV Integration Global Biogeochemical Cycles Introduction 335 The Global Carbon Cycle 335 Long-Term Change in Atmospheric CO2 337 Anthropogenic Changes in the Carbon Cycle 33g Terrestrial Sinks for CO2............ 340 The Global Methane Budget ..................... 342
Contents xiii Disturbance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 Conceptual Framework . . . . . . . . . . . . . . . . . . . . . . . . 285 Disturbance Properties . . . . . . . . . . . . . . . . . . . . . . . . . 285 Succession . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288 Ecosystem Structure and Composition . . . . . . . . . . . . 288 Carbon Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292 Nutrient Cycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296 Trophic Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 Water and Energy Exchange . . . . . . . . . . . . . . . . . . . . 299 Temporal Scaling of Ecological Processes . . . . . . . . . . . . 301 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304 Chapter 14 Landscape Heterogeneity and Ecosystem Dynamics Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305 Concepts of Landscape Heterogeneity . . . . . . . . . . . . . . 305 Causes of Spatial Heterogeneity . . . . . . . . . . . . . . . . . . . 307 State Factors and Interactive Controls . . . . . . . . . . . . . 307 Community Processes and Legacies . . . . . . . . . . . . . . . 307 Disturbance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309 Interactions Among Sources of Heterogeneity . . . . . . 311 Patch Interactions on the Landscape . . . . . . . . . . . . . . . . 314 Topographic and Land-Water Interactions . . . . . . . . . 314 Atmospheric Transfers . . . . . . . . . . . . . . . . . . . . . . . . . 317 Movement of Plants and Animals on the Landscape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320 Disturbance Spread . . . . . . . . . . . . . . . . . . . . . . . . . . . 320 Human Land Use Change and Landscape Heterogeneity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321 Extensification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321 Intensification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 Spatial Heterogeneity and Scaling . . . . . . . . . . . . . . . . . . 325 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330 Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331 Part IV Integration Chapter 15 Global Biogeochemical Cycles Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335 The Global Carbon Cycle . . . . . . . . . . . . . . . . . . . . . . . . 335 Long-Term Change in Atmospheric CO2 . . . . . . . . . . . 337 Anthropogenic Changes in the Carbon Cycle . . . . . . . 339 Terrestrial Sinks for CO2 . . . . . . . . . . . . . . . . . . . . . . . 340 The Global Methane Budget . . . . . . . . . . . . . . . . . . . . . . 342