Methods of Studying Root Systems - Böhm, W.

. .

Sommaire:
1. Root Ecology and Root Physiology.- 2. General Survey of Root-Study Methods.- 2.1 Historical Development.- 2.2 Principles of Classification.- 2.3 Selection of the Best Method.- 3. Excavation Methods.- 3.1 Introduction.- 3.2 Outline of the Classical Method.- 3.3 Modifications of the Classical Method.- 4. Monolith Methods.- 4.1 Introduction.- 4.2 Simple Spade Methods.- 4.3 The Common Monolith Method.- 4.4 Box Methods.- 4.5 Cage Methods.- 4.6 Needleboard Methods.- 5. Auger Methods.- 5.1 Specific Features.- 5.2 Sampling Techniques.- 5.3 The Core-Break Method.- 5.4 Advantages and Drawbacks.- 6. Profile Wall Methods.- 6.1 General Survey.- 6.2 The Traditional Trench Profile Method.- 6.3 The Foil Method.- 6.4 Technique in a Horizontal Plane.- 6.5 Evaluation and Applications.- 7. Glass Wall Methods.- 7.1 Introduction.- 7.2 Glass-Faced Profile Walls.- 7.3 Root Laboratories.- 7.4 Root Observations with Glass Tubes.- 7.5 Evaluation of the Methods.- 8. Indirect Methods.- 8.1 Introduction.- 8.2 Determination of Soil Water Content.- 8.3 Staining Techniques.- 8.4 Uptake of Non-Radioactive Tracers.- 8.5 Radioactive Tracer Methods.- 9. Other Methods.- 9.1 Measuring Root-Pulling Strength.- 9.2 Measuring Root-Clump Weight.- 9.3 Measuring Root Tensile Strength.- 9.4 Root Measurements Using Soil Sections.- 9.5 Root-Detecting Method.- 9.6 Mesh Bag Method.- 9.7 Root Replacement Method.- 9.8 Root Investigations with Paper Chromatography.- 9.9 Electrical Methods.- 9.10 Determination of Growth Rings in Tree Roots.- 9.11 Investigations of Root Hairs.- 9.12 Determination of Root Nodules.- 9.13 Determination of Mycorrhizae.- 10. Container Methods.- 10.1 General Features.- 10.2 Rooting Volume and Container Size.- 10.3 Types of Containers.- 10.4 Rooting Media.- 10.5 Filling the Containers.- 10.6 Seed Technique.- 10.7 Irrigation Problems.- 10.8 Special Washing Procedures.- 10.9 Modified Container Methods.- 10.10 Root Studies in Nutrient Solutions.- 10.11 Root Studies in Mist Chambers.- 10.12 Comparability of Results from Container Experiments with Field Data.- 11. Techniques of Root Washing.- 11.1 Dry Sieving.- 11.2 Storing Soil-Root Samples Before Washing.- 11.3 Chemicals for Facilitating Root Washing.- 11.4 Washing Roots by Hand.- 11.5 Flotation Method.- 11.6 Root-Washing Machines.- 11.7 Nutrient Losses from Roots During Washing.- 11.8 Cleaning Roots from Debris.- 11.9 Storing Roots After Washing.- 12. Root Parameters and Their Measurement.- 12.1 General Aspects.- 12.2 Root Number.- 12.3 Root Weight.- 12.4 Root Surface.- 12.5 Root Volume.- 12.6 Root Diameter.- 12.7 Root Length.- 12.8 Root Tips.- 12.9 Shoot-Root Relations.- 13. Some Future Aspects for the Use of Ecological Root-Study Methods.- References.