The soil fauna of a beech forest on limestone: trophic structure and energy budget

摘要: The soil fauna of a mull beech forest on lime-stone in southern Lower Saxony (West Germany) was sampled quantitatively. Biomass estimates, trophic characteristics, and measurement calculation the energetic parameters constituent animal populations were used to construct an energy budget total heterotrophic subsystem forest. Mean annual zoomass amounted about 15 g d wt m−2; earthworms (about 10 m−2) other groups macrofauna dominant. Protozoa constituted 1.5 m−2. Relative distribution among categories 50% macrosaprophages, 30% microsaprophages, 12% microphytophages, 4% zoophages. Total consumption rate saprophagous microphytophagous (6328 4096 kJ m−2 yr−1, respectively) same order magnitude as litter fall (canopy leaves 6124 flowers fruits 944 herbs 1839 fine woody material 870 tree roots 3404 without coarse litter). Primary decomposers (macrosaprophages) key group for comminution translocation onto into soil, thus contributing high decomposition (k=0.8) leaf litter. Consumption rates (values yr−1): bacteriophages 2954, micromycophages 416, zoophages 153. Grazing pressure macrophytophages (including rhizophages) low. Faeces input from canopy layer not significant. microflora almost equalled microbial biomass; hence, large fraction production is channelled component. Predator animals high, comparison between by potential prey — mainly microphytophages demonstrated. Soil contributed only 11% respiration. However, there evidence that are important driving variables matter transfer: processes transformation dead organic grazing microflora. It hypothesized macrosaprophages donor-limited.