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Summary: Role of the anecic earthworm Lumbricus terrestris L.
in the distribution of plant residue nitrogen
in a corn (Zea mays)soil system
Jose´ A. Amador *, Josef H. Go¨rres
Laboratory of Soil Ecology and Microbiology, 024 Coastal Institute in Kingston,
University of Rhode Island, Kingston, RI 02881, USA
Received 13 September 2004; accepted 6 February 2005
Abstract
While the benefits of earthworms to crop production are widely acknowledged, the mechanisms involved are poorly
understood. We examined the effects of an anecic earthworm (Lumbricus terrestris) on the distribution of plant residue N in a
corn (Zea mays)/soil system. Soil (mixed Ap and B horizons) mesocosms (10 cm diameter, 39 cm deep) were amended with 15
N-
labeled corn litter, inoculated with one earthworm per mesocosm (WORM) or none (CTRL), and pre-incubated for 1, 2 or 3
weeks. Earthworms and remaining plant residues were removed and sweet corn grown in the mesocosms in a greenhouse for 3
weeks. Litter, earthworms, shoots, roots and bulk and burrow soil were analyzed for total N and 15
N. Plant and earthworm
biomass were also determined. Earthworms had no significant effect on the N content of shoots, roots or bulk soil. Recovery of
15
N ranged from 92.6 to 101.9% in CTRL and 60.2 to 83.2% in the WORM treatment. The 15
N content of bulk soil in the WORM
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