Methods to study litter decomposition : a practical guide

Decomposition of organic matter is a major ecosystem process involving an array of different organisms, including bacteria, fungi and invertebrates. The main objective of this book is to provide students and laboratory instructors at universities and professional ecologists with a broad range of established methods to study plant litter decomposition. Detailed protocols for direct use in the field or laboratory are presented in an easy to follow step-by-step format. A short introduction to each protocol reviews the ecological significance and principles of the technique and points to key references. Although most methods are described for freshwater ecosystems, many will work equally well in the presented or slightly modified form for studies in marine and terrestrial environments. TABLE OF CONTENTS......Page 5 PREFACE......Page 9 PART 1. LITTER DYNAMICS......Page 11 1. Litter Input......Page 12 2. Leaf Retention......Page 21 3. Manipulation of Stream Retentiveness......Page 27 4. Coarse Benthic Organic Matter......Page 33 5. Leaching......Page 40 6. Leaf Mass Loss Estimated by Litter Bag Technique......Page 44 7. Coarse Particulate Organic Matter Budgets......Page 50 PART 2. LEAF CHEMICAL AND PHYSICAL PROPERTIES......Page 58 8. Determination of Total Nitrogen and Phosphorus in Leaf Litter......Page 59 9. Total Protein......Page 66 10. Free Amino Acids......Page 73 11. Determination of Total Carbohydrates......Page 79 12. Determination of Soluble Carbohydrates......Page 88 13. Total Lipids......Page 94 14. Total Phenolics......Page 99 15. Radial Diffusion Assay for Tannins......Page 103 16. Acid Butanol Assay for Proanthocyanidins (Condensed Tannins)......Page 108 17. Proximate Lignin and Cellulose......Page 115 18. Leaf Toughness......Page 121 PART 3. MICROBIAL DECOMPOSERS......Page 126 19. Techniques for Handling Ingoldian Fungi......Page 127 20. Maintenance of Aquatic Hyphomycete Cultures......Page 140 21. An Illustrated Key to the Common Temperate Species of Aquatic Hyphomycetes......Page 149 22. Molecular Approaches to Estimate Fungal Diversity. I. Terminal Restriction Fragment Length Polymorphism (T-RFLP)......Page 164 23. Molecular Approaches to Estimate Fungal Diversity. II. Denaturing Gradient Gel Electrophoresis (DGGE)......Page 172 24. Sporulation of Aquatic Hyphomycetes......Page 179 25. Ergosterol as a Measure of Fungal Biomass......Page 183 26. Acetate Incorporation into Ergosterol to Determine Fungal Growth Rates and Production......Page 190 27. Bacterial Counts and Biomass Determination by Epifluorescence Microscopy......Page 196 28. Secondary Production and Growth of Litter-Associated Bacteria......Page 202 29. Isolation of Cellulose-degrading Bacteria......Page 209 30. Extraction and Quantification of ATP as a Measure of Microbial Biomass......Page 215 31. Respirometry......Page 222 PART 4. ENZYMATIC CAPABILITIES......Page 228 32. Extractellular Fungal Hydrolytic Enzyme Activity......Page 229 33. Cellulases......Page 239 34. Viscosimetric Determination of Endocellulase Activity......Page 245 35. Fluorometric Determination of the Activity of β-Glucosidase and other Extracellular Hydrolytic Enzymes......Page 251 36. Pectin-Degrading Enzymes: Polygalacturonase and Pectin Lyase......Page 257 37. Lignin-Degrading Enzymes: Phenoloxidase and Peroxidase......Page 262 38. Phenol Oxidation......Page 267 39. Proteinase Activity: Azocoll and Thin-Layer Enzyme Assay......Page 271 PART 5. DETRITIVOROUS CONSUMERS......Page 277 40. Maintenance of Shredders in the Laboratory......Page 278 41. Feeding Preferences of Shredders......Page 283 PART 6. DATA ANALYSIS......Page 289 42. A Primer for Statistical Analysis......Page 290 43. Biodiversity......Page 298 The primary objective of this book is to provide students and laboratory instructors at universities and professional ecologists with a broad range of established methods to study plant litter decomposition. Detailed protocols for direct use in the field or laboratory are presented in an easy to follow step-by-step format. A short introduction to each protocol reviews the ecological significance and principles of the technique and points to key references. Allochthonous plant litter is a major source of carbon and energy for stream organisms, especially in narrow reaches where riparian cover limits primary production (Vannote et al. 1980, Webster & Meyer 1997). Edited By Manuel A.s. Graça, Felix Bärlocher And Mark O. Gessner. Includes Bibliographical References.