Microflora, Protozoa and Nematoda in Lumbricus terrestris burrow ...

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May 8, 2000 - Anecic earthworms Lumbricus terrestris L. were kept in laboratory microcosms con- taining soil and litter from a lime (Tilia cordata) and beech ...

Pedobiologia 45, 46–60 (2001) © Urban & Fischer Verlag http://www.urbanfischer.de/journals/pedo

Microflora, Protozoa and Nematoda in Lumbricus terrestris burrow walls: a laboratory experiment Alexei V. Tiunov1*, Michael Bonkowski2,3, Jörn Alphei3 and Stefan Scheu4 Institute of Ecology and Evolution, Leninsky Prospect 33, 117071 Moscow, Russia NERC Centre for Population Biology, Imperial College at Silwood Park, Ascot SL5 7PY, UK 3 Universität Göttingen, Institut für Zoologie und Anthropologie, Abt. Ökologie, 37073 Göttingen, Germany 4 Technische Universität Darmstadt, Institut für Zoologie, Schnittspahnstr. 3, 64287 Darmstadt, Germany 1 2

Submitted: 8. May 2000 Accepted: 16. August 2000

Summary Anecic earthworms Lumbricus terrestris L. were kept in laboratory microcosms containing soil and litter from a lime (Tilia cordata) and beech (Fagus sylvatica) forest. Nutrient (mineral nitrogen and phosphorus) contents, microbial activity and densities of protozoa and nematodes were determined in burrow walls and control soils after 165 days. Well-developed burrow linings consisting of earthworm faeces were formed in the “Tilia” treatment, but not in the “Fagus” treatment, presumably because beech litter was not an adequate food resource for L. terrestris. Consequently, increases in microbial biomass, basal respiration and microbial volume in burrow walls compared to surrounding soil were significant in the “Tilia” treatment only. However, in both treatments burrow walls were strongly enriched in mineral nitrogen and phosphorus. The density and biomass of protozoa were significantly greater in burrow walls compared to the control soil. The numbers of naked amoebae increased by similar factors of 4 and 3.5 in burrow walls of the “Tilia” and “Fagus” treatment, respectively. Flagellate density increased more than tenfold in burrow walls of the “Tilia” treatment but only twofold in the “Fagus” treatment. In addition, a comparatively large ciliate population was present in burrow walls in the “Tilia” treatment. The total abundance of protozoa was significantly correlated with the contents of inorganic N *E-mail corresponding author: [email protected]

0031–4056/01/45/01–46 $ 15.00/0

Microflora and microfauna in earthworm burrow walls

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and P in the samples (r=0.68 and 0.63 respectively, P