SOIL INVERTEBRATES - EFFECTS ON NUTRIENT TURNOVER AND SOIL STRUCTURE - A REVIEW

This paper intends to stimulate discussion between zoologists and soil scientists by presenting some central problems of descriptive and functional soil zoology. These problems are related to a. the cryptic life of soil biota, b. their specific adaptations to the soil habitat, c. the different spatio-temporal scales at which invertebrates affect soil processes, d. the extremely different ways invertebrate effects in soil can be quantified and e. the close interrelationships between all components of the soil subsystem. A short outline is given of the different functional groups and trophic systems which have been used as tools for estimating the impact of soil invertebrates on soil, higher plants and edaphon. The difficulty of differentiating between direct and indirect effects is discussed. Especially in the context of soil structural research, many of the investigations have focussed on the direct contribution of the macrofauna to structure formation, while indirect effects of the meso and microfauna on structure stabilization have largely been ignored. In conclusion some special fields are proposed for intensive cooperation between soil scientists and soil zoologists in the future.