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Article: Exotic earthworm invasion increases soil carbon and nitrogen in an old-growth forest in southern Quebec.
- Article from:
- Canadian Journal of Forest Research
- Article date:
- April 1, 2006
- Author:
CopyrightCOPYRIGHT 2006 NRC Research Press. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Abstract: To test whether invasion of exotic earthworms affects soil carbon (C) and nitrogen (N), we sampled the litter and upper mineral soil (to 30 cm) at a series of sites varying in their earthworm populations in an old-growth beech-maple forest at Mont St. Hilaire, southern Quebec. We measured earthworm abundance and biomass using hand-sorting and chemical extraction (allyl isothiocyanate) methods. They gave similar results, though there was evidence of size and species-specific biases. Abundance and biomass of the earthworms ranged from
<10 to>100 earthworms x [m.sup.-2] and from
<10 to 125 g x [m.sup.-2], respectively, and were correlated with distance from a nearby lake (negatively) and soil pH (positively). The presence of earthworms was associated with a decrease in the mass and thickness and an increase in the C/N quotient of the litter layer. There were no significant changes in C and N mass of the mineral soil between 0 and 10 cm, but the underlying layers (10-20 and 20-30 cm) in sites with>10 earthworms x [m.sup.-2] showed significantly (p
<10 to>10 earthworms x [m.sup.-2] may increase ...
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