The Central Amazon Floodplain

Transcription

1 W.J. Junk (Ed.) The Central Amazon Floodplain Ecology of a Pulsing System With 137 Figures and 72 Tables Springer

2 Contents Part I: Introductory Remarks 1 General Aspects of Floodplain Ecology with Special Reference to Amazonian Floodplains Wolfgang J. Junk Introduction Definition and General Characterization The Flood Pulse Concept Floodplains and Limnological Terminology Distribution and Size of Neotropical Floodplains Human Impact 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 Formation of Varzea and Igapo Characterization of the Study Area Climate and Hydrology Grain Size and Mineralogical Composition Sediment Transport and Deposition Geomorphological Aspects Discussion and Conclusions 44

3 XII Contents 3 Chemistry of Varzea and Igapo Soils and Nutrient Inventory of Their Floodplain Forests Karin Furch Introduction Methods Total Element Content Metals (K, Na, Mg, and Ca) Nonmetals (C, N, S, and P) Cation Exchange Capacity Content of Soluble Substances in Aqueous Soil Extracts Bioelement Stock in the Systems and Bioelement Fluxes Between Soil and Forest Vegetation Discussion and Conclusions 62 4 Physicochemical Conditions in Floodplains Karin Furch and Wolfgang J. Junk Introduction Light Regime Chemistry of Different Water Types The Solimoes/Amazon River Near Manaus The Negro River Near Manaus Terra Firme Affluents Amazonian Rainwater : Groundwater Physicochemical Attributes of Different Varzea Lakes The Influence of Different Waters on the Chemistry of Varzea Lakes Thermal and Chemical Stratification and Mixing Patterns The Oxygen Concentration in Varzea Lakes Processes Within Lakes Land-Water Interactions and the Bioelement Cycles Discussion and Conclusions 107

4 Contents 5 Modelling Nutrient Fluxes in Floodplain Lakes Gerhard E. Weber 109 XIII 5.1 Introduction Conceptual Considerations Modelling Cation Seasonality in Lago Camaleao Discussion Nitrogen Turnover in the Varzea Jiirgen Kern and Assad Darwich Introduction Methods Exchange of Nitrogen Compounds Between the River and the Floodplain Nitrogen Input by Dry and Wet Deposition Nitrogen Flux at the Sediment-Water Interface Nitrogen Flux Within Higher Vegetation Nitrogen Input by N 2 Fixation Output of Gaseous Nitrogen Compounds (N 2, N 2 O, NO X ) by Denitrification Mass Balance of Nitrogen at Lago Camaleao Methane Emissions from the Amazon Floodplain Reiner Wassmann and Christopher Martius Introduction The Habitats of the Varzea Ecosystem Processes Involved in the Methane Budget of the Varzea Spatial and Seasonal Variation in Methane Emission Rates Methane Emission from Termites Significance of Methane Emission from the Varzea in the Regional and Global Context 142

5 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 Introduction General Distribution of the Vegetation Distribution According to the Duration of the Aquatic and Terrestrial Phases Distribution According to Sedimentation and Erosion Successional Processes Anthropogenic Influences on the Vegetation Pattern Site Conditions, Community Structure and Adaptations of the Herbaceous Vegetation of the Varzea The Most Important Habitats in the Varzea and Their Herbaceous Plants Species Richness and Distribution Adaptations to the Flood Pulse Herbaceous Plants of the Igapo Biomass and Primary Production The Relative Growth Rate (RGR) of Floating Species Biomass and Net Primary Production of Rooted Species Net Primary Production and Nutrient Supply Light Utilization and Photosynthetic Activity Discussion and Conclusions The Chemical Composition, Food Value, and Decomposition of Herbaceous Plants, Leaves, and Leaf Litter of the Floodplain Forests Karin Furch and Wolfgang J. Junk Introduction Herbaceous Plants 188

6 Contents XV Chemical Composition and Nutritive Values of the Plants Decomposition During the Terrestrial and the Aquatic Phases Release of Dissolved Substances into the Water Leaf Litter Consistency and Chemical Composition of Tree Leaves and Leaf Litter Decomposition in Water and on Land The Impact of Terrestrial Invertebrates on Leaf Litter Decomposition The Impact of Aquatic Invertebrates on Leaf Litter Decomposition Discussion and Conclusions Phytoplankton and Periphyton Rainer Putz and Wolfgang J. Junk Introduction Phytoplankton Species Number and Community Structure Biomass and Primary Production Periphyton Species Number and Community Structure Biomass and Primary Production Discussion and Conclusions The Forest Ecosystem of the Floodplains Martin Worbes Introduction Floristics and Forest Structure Species Diversity Floristic Relationships Between Amazonian Varzea, Igapo and Terra Firme Plant Communities and Site Conditions in the Igapo Plant Communities and Site Conditions in the Varzea 231

7 XVI Contents 11.3 Responses to the Flood Pulse Leaf-Fall Behaviour ' Periodical Growth of Roots, Wood and Shoots Morphological and Physiological Adaptations of the Roots Reproduction ' Zonation Biomass and Primary Production Litter Production Root Production Wood Increment Total Net Primary Production Discussion and Conclusions Decomposition of Wood Christopher Martius Introduction Wood Litter Production and Distribution Wood Mineralization in the Terrestrial Phase: Decay Rates of Boles Aquatic Wood Decay and the Role of the Flood Pulse Carbon Cycling Through Wood-Feeding Termite Populations Discussion and Conclusions 276 Part IV: Animal Life in the Floodplain 13 Aquatic Invertebrates Wolfgang J. Junk and Barbara A. Robertson Introduction The ooplankton The Benthos The Perizoon The Fauna of the Aquatic Macrophytes 289

8 Contents XVII The Fauna of the Submerged Canopy of the Floodplain Forest Key Aquatic Invertebrates Discussion and Conclusions Terrestrial Invertebrates: Survival Strategies, Group Spectrum, Dominance and Activity Patterns Joachim Adis Introduction Survival Strategies Group Spectrum, Dominance and Activity Patterns Arthropods of Varzea Forests Arthropods of Igapo Forests Discussion and Conclusions Adaptations to Life Under Water: Tiger Beetles and Millipedes Joachim Adis and Benjamin Messner Introduction Results and Discussion Tiger Beetles (Coleoptera: Carabidae: Cicindelinae) Millipedes (Diplopoda: Polydesmida) The Oribatid Mites Elisabeth Franklin, Joachim Adis, and Steffan Woas Introduction Results and Discussion Fauna of Litter and Soil Fauna of Tree Trunks Reaction of Oribatid Mites to the Flood Pulse Faunal Differences 348

9 XVIII Contents 17 The Collembola Ulrich Gauer Introduction Species Inventory Phenology and Abundance Adaptation to the Flood Pulse: Recolonization After Receding Floodwaters in the Igapo Discussion and Conclusions The Termites Christopher Martius Introduction Diversity and Biology of Floodplain-Inhabiting Termites Abundance, Distribution, and Exchange Rate Termite Nests as Structural Elements Discussion and Conclusions The Spider Communities Hubert Hofer Introduction Species Inventories Species Identity in the Two Floodplain Forests and the Terra Firme Forest Phenology of Abundance and Activity Density on the Ground and on Tree Trunks Discussion and Conclusions 380

10 Contents XIX 20 The Fish Wolfgang J. Junk, Maria G.M. Soares, and Ulrich Saint-Paul Introduction " Food Availability and Feeding Habits Biomass, Growth Rates, and Production Reproductive Strategies Adaptations to Hypoxia Species Diversity Discussion and Conclusions Mammals, Reptiles and Amphibians Wolfgang J. Junk and Vera Maria F. da Silva Introduction Mammals Reptiles Amphibians Discussion and Conclusions The Birds Peter Petermann Introduction The Environment of Birds: Dynamics and Structures Species Numbers Migrants Wetland Species Varzea Species Biogeographic Relationships Habitat Preferences Sandbar Floating Meadows Sandbar Scrub and Lakeside Scrub 440

11 XX Contents Varzea Forest Dispersal Capabilities Discussion Species Composition Conclusions 451 Part V: Conclusions 23 Structure and Function of the Large Central Amazonian River Floodplains: Synthesis and Discussion Wolfgang J. Junk Habitat Diversity and Dynamics The Impact of Global Paleoclimatic Changes on Amazonian Floodplains Species Diversity Adaptations to the Flood Pulse Biomass and Primary Production Food Webs 468 References 473 Subject Index 521