W.J. Junk (Ed.) The Central Amazon Floodplain Ecology of a Pulsing System With 137 Figures and 72 Tables Springer
Contents Part I: Introductory Remarks 1 General Aspects of Floodplain Ecology with Special Reference to Amazonian Floodplains Wolfgang J. Junk 3 1.1 Introduction 3 1.2 Definition and General Characterization 6 1.3 The Flood Pulse Concept 8 1.4 Floodplains and Limnological Terminology 10 1.5 Distribution and Size of Neotropical Floodplains.. 12 1.6 Human Impact 16 1.7 Objectives and Structure of This Book 17 Part II: The Physical and Chemical Environment 2 The Large Central Amazonian River Floodplains Near Manaus: Geological, Climatological, Hydrological, and Geomorphological Aspects Georg Irion, Wolfgang J. Junk, and Jose A.S.N. de Mello 23 2.1 Formation of Varzea and Igapo 23 2.2 Characterization of the Study Area 29 2.3 Climate and Hydrology 30 2.4 Grain Size and Mineralogical Composition 35 2.5 Sediment Transport and Deposition 37 2.6 Geomorphological Aspects 41 2.7 Discussion and Conclusions 44
XII Contents 3 Chemistry of Varzea and Igapo Soils and Nutrient Inventory of Their Floodplain Forests Karin Furch 47 3.1 Introduction 47 3.2 Methods 48 3.3 Total Element Content 53 3.3.1 Metals (K, Na, Mg, and Ca) 53 3.3.2 Nonmetals (C, N, S, and P) 54 3.4 Cation Exchange Capacity 55 3.5 Content of Soluble Substances in Aqueous Soil Extracts 56 3.6 Bioelement Stock in the Systems and Bioelement Fluxes Between Soil and Forest Vegetation 58 3.7 Discussion and Conclusions 62 4 Physicochemical Conditions in Floodplains Karin Furch and Wolfgang J. Junk 69 4.1 Introduction 69 4.2 Light Regime 71 4.3 Chemistry of Different Water Types 73 4.3.1 The Solimoes/Amazon River Near Manaus 73 4.3.2 The Negro River Near Manaus 77 4.3.3 Terra Firme Affluents 82 4.3.4 Amazonian Rainwater : 85 4.3.5 Groundwater 92 4.4 Physicochemical Attributes of Different Varzea Lakes 94 4.4.1 The Influence of Different Waters on the Chemistry of Varzea Lakes 94 4.4.2 Thermal and Chemical Stratification and Mixing Patterns 98 4.4.3 The Oxygen Concentration in Varzea Lakes 100 4.4.4 Processes Within Lakes 104 4.4.5 Land-Water Interactions and the Bioelement Cycles 105 4.5 Discussion and Conclusions 107
Contents 5 Modelling Nutrient Fluxes in Floodplain Lakes Gerhard E. Weber 109 XIII 5.1 Introduction 109 5.2 Conceptual Considerations 109 5.3 Modelling Cation Seasonality in Lago Camaleao... 112 5.4 Discussion 116 6 Nitrogen Turnover in the Varzea Jiirgen Kern and Assad Darwich 119 6.1 Introduction 119 6.2 Methods 119 6.3 Exchange of Nitrogen Compounds Between the River and the Floodplain 122 6.4 Nitrogen Input by Dry and Wet Deposition 124 6.5 Nitrogen Flux at the Sediment-Water Interface... 126 6.6 Nitrogen Flux Within Higher Vegetation 127 6.7 Nitrogen Input by N 2 Fixation 127 6.8 Output of Gaseous Nitrogen Compounds (N 2, N 2 O, NO X ) by Denitrification 132 6.9 Mass Balance of Nitrogen at Lago Camaleao 134 7 Methane Emissions from the Amazon Floodplain Reiner Wassmann and Christopher Martius... 137 7.1 Introduction 137 7.2 The Habitats of the Varzea Ecosystem 137 7.3 Processes Involved in the Methane Budget of the Varzea 138 7.4 Spatial and Seasonal Variation in Methane Emission Rates 140 7.5 Methane Emission from Termites 141 7.6 Significance of Methane Emission from the Varzea in the Regional and Global Context 142
XIV Contents Part III: Plant Life in the Floodplain 8 Plant Life in the Floodplain with Special Reference to Herbaceous Plants Wolfgang J. Junk and Maria Teresa F. Piedade... 147 8.1 Introduction 147 8.2 General Distribution of the Vegetation 148 8.2.1 Distribution According to the Duration of the Aquatic and Terrestrial Phases 148 8.2.2 Distribution According to Sedimentation and Erosion 150 8.2.3 Successional Processes 151 8.2.4 Anthropogenic Influences on the Vegetation Pattern 153 8.3 Site Conditions, Community Structure and Adaptations of the Herbaceous Vegetation of the Varzea 154 8.3.1 The Most Important Habitats in the Varzea and Their Herbaceous Plants 158 8.3.2 Species Richness and Distribution 160 8.3.3 Adaptations to the Flood Pulse 162 8.4 Herbaceous Plants of the Igapo 167 8.5 Biomass and Primary Production 168 8.5.1 The Relative Growth Rate (RGR) of Floating Species 168 8.5.2 Biomass and Net Primary Production of Rooted Species 170 8.5.3 Net Primary Production and Nutrient Supply 175 8.5.4 Light Utilization and Photosynthetic Activity 176 8.6 Discussion and Conclusions 181 9 The Chemical Composition, Food Value, and Decomposition of Herbaceous Plants, Leaves, and Leaf Litter of the Floodplain Forests Karin Furch and Wolfgang J. Junk 187 9.1 Introduction 187 9.2 Herbaceous Plants 188
Contents XV 9.2.1 Chemical Composition and Nutritive Values of the Plants 188 9.2.2 Decomposition During the Terrestrial and the Aquatic Phases 193 9.2.3 Release of Dissolved Substances into the Water.... 195 9.3 Leaf Litter 197 9.3.1 Consistency and Chemical Composition of Tree Leaves and Leaf Litter 197 9.3.2 Decomposition in Water and on Land 199 9.3.3 The Impact of Terrestrial Invertebrates on Leaf Litter Decomposition 201 9.3.4 The Impact of Aquatic Invertebrates on Leaf Litter Decomposition 202 9.4 Discussion and Conclusions 203 10 Phytoplankton and Periphyton Rainer Putz and Wolfgang J. Junk 207 10.1 Introduction 207 10.2 Phytoplankton 208 10.2.1 Species Number and Community Structure 208 10.2.2 Biomass and Primary Production 209 10.3 Periphyton 212 10.3.1 Species Number and Community Structure 212 10.3.2 Biomass and Primary Production 214 10.4 Discussion and Conclusions 219 11 The Forest Ecosystem of the Floodplains Martin Worbes 223 11.1 Introduction. 223 11.2 Floristics and Forest Structure. 223 11.2.1 Species Diversity 224 11.2.2 Floristic Relationships Between Amazonian Varzea, Igapo and Terra Firme 226 11.2.3 Plant Communities and Site Conditions in the Igapo 229 11.2.4 Plant Communities and Site Conditions in the Varzea 231
XVI Contents 11.3 Responses to the Flood Pulse 236 11.3.1 Leaf-Fall Behaviour '. 236 11.3.2 Periodical Growth of Roots, Wood and Shoots... 237 11.3.3 Morphological and Physiological Adaptations of the Roots 241 11.3.4 Reproduction '. 245 11.3.5 Zonation 247 11.4 Biomass and Primary Production 249 11.4.1 Litter Production 249 11.4.2 Root Production 251 11.4.3 Wood Increment 254 11.4.4 Total Net Primary Production 259 11.5 Discussion and Conclusions 260 12 Decomposition of Wood Christopher Martius 267 12.1 Introduction 267 12.2 Wood Litter Production and Distribution 267 12.3 Wood Mineralization in the Terrestrial Phase: Decay Rates of Boles 269 12.4 Aquatic Wood Decay and the Role of the Flood Pulse 271 12.5 Carbon Cycling Through Wood-Feeding Termite Populations 273 12.6 Discussion and Conclusions 276 Part IV: Animal Life in the Floodplain 13 Aquatic Invertebrates Wolfgang J. Junk and Barbara A. Robertson 279 13.1 Introduction 279 13.2 The ooplankton 279 13.3 The Benthos 286 13.4 The Perizoon 289 13.4.1 The Fauna of the Aquatic Macrophytes 289
Contents XVII 13.4.2 The Fauna of the Submerged Canopy of the Floodplain Forest 292 13.5 Key Aquatic Invertebrates 293 13.6 Discussion and Conclusions 296 14 Terrestrial Invertebrates: Survival Strategies, Group Spectrum, Dominance and Activity Patterns Joachim Adis 299 14.1 Introduction 299 14.2 Survival Strategies 300 14.3 Group Spectrum, Dominance and Activity Patterns 303 14.3.1 Arthropods of Varzea Forests 303 14.3.2 Arthropods of Igapo Forests 311 14.4 Discussion and Conclusions 314 15 Adaptations to Life Under Water: Tiger Beetles and Millipedes Joachim Adis and Benjamin Messner 319 15.1 Introduction 319 15.2 Results and Discussion 319 15.2.1 Tiger Beetles (Coleoptera: Carabidae: Cicindelinae) 319 15.2.2 Millipedes (Diplopoda: Polydesmida) 324 16 The Oribatid Mites Elisabeth Franklin, Joachim Adis, and Steffan Woas.. 331 16.1 Introduction 331 16.2 Results and Discussion 332 16.2.1 Fauna of Litter and Soil 332 16.2.2 Fauna of Tree Trunks 335 16.2.3 Reaction of Oribatid Mites to the Flood Pulse 342 16.3 Faunal Differences 348
XVIII Contents 17 The Collembola Ulrich Gauer 351 17.1 Introduction 351 17.2 Species Inventory 351 17.3 Phenology and Abundance 352 17.4 Adaptation to the Flood Pulse: Recolonization After Receding Floodwaters in the Igapo 354 17.5 Discussion and Conclusions 357 18 The Termites Christopher Martius 361 18.1 Introduction 361 18.2 Diversity and Biology of Floodplain-Inhabiting Termites 361 18.3 Abundance, Distribution, and Exchange Rate 365 18.4 Termite Nests as Structural Elements 369 18.5 Discussion and Conclusions 370 19 The Spider Communities Hubert Hofer 373 19.1 Introduction 373 19.2 Species Inventories 373 19.3 Species Identity in the Two Floodplain Forests and the Terra Firme Forest 376 19.4 Phenology of Abundance and Activity Density on the Ground and on Tree Trunks 378 19.5 Discussion and Conclusions 380
Contents XIX 20 The Fish Wolfgang J. Junk, Maria G.M. Soares, and Ulrich Saint-Paul 385 20.1 Introduction " 385 20.2 Food Availability and Feeding Habits 386 20.3 Biomass, Growth Rates, and Production 391 20.4 Reproductive Strategies 393 20.5 Adaptations to Hypoxia 397 20.6 Species Diversity 402 20.7 Discussion and Conclusions 405 21 Mammals, Reptiles and Amphibians Wolfgang J. Junk and Vera Maria F. da Silva 409 21.1 Introduction 409 21.2 Mammals 409 21.3 Reptiles 412 21.4 Amphibians 415 21.5 Discussion and Conclusions 416 22 The Birds Peter Petermann 419 22.1 Introduction 419 22.2 The Environment of Birds: Dynamics and Structures 420 22.3 Species Numbers 421 22.3.1 Migrants 425 22.3.2 Wetland Species.. 428 22.3.3 Varzea Species 433 22.4 Biogeographic Relationships 433 22.5 Habitat Preferences 435 22.5.1 Sandbar 436 22.5.2 Floating Meadows 438 22.5.3 Sandbar Scrub and Lakeside Scrub 440
XX Contents 22.5.4 Varzea Forest 440 22.6 Dispersal Capabilities 442 22.7 Discussion 445 22.7.1 Species Composition 445 22.7.2 Conclusions 451 Part V: Conclusions 23 Structure and Function of the Large Central Amazonian River Floodplains: Synthesis and Discussion Wolfgang J. Junk 455 23.1 Habitat Diversity and Dynamics 455 23.2 The Impact of Global Paleoclimatic Changes on Amazonian Floodplains 457 23.3 Species Diversity 459 23.4 Adaptations to the Flood Pulse 464 23.5 Biomass and Primary Production 465 23.6 Food Webs 468 References 473 Subject Index 521