Increased atmospheric CO sub(2) and litter quality: Decomposition of sweet chestnut leaf litter with animal food webs of different complexities

Two-year-old chestnut trees were grown for two yr under ambient (350 ppm) and enriched (700 ppm) CO sub(2) concentrations, in two naturally lit growth chambers. The doubling of CO sub(2) resulted in a dilution of the nitrogen concentration in the leaf litter, with C:N ratios of 40 and 75 for the amb...

Full description

Saved in:
Bibliographic Details
Published in:Oikos 1991-01, Vol.61 (1), p.54-64
Main Authors: Couteaux, M-M, Mousseau, M, Celerier, M-L, Bottner, P
Format: Article
Language:English
Subjects:
Collembola
Isopoda
Nematoda
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Two-year-old chestnut trees were grown for two yr under ambient (350 ppm) and enriched (700 ppm) CO sub(2) concentrations, in two naturally lit growth chambers. The doubling of CO sub(2) resulted in a dilution of the nitrogen concentration in the leaf litter, with C:N ratios of 40 and 75 for the ambient and enriched CO sub(2) concentrations, respectively. The litter was sterilized and inoculated with microflora and animal groups of increasing complexity (microflora + Protozoa; + nematodes; + Collembola; + Isopoda) and incubated over 24 wk. Every two wk, the CO sub(2) release was measured and the litter was leached with demineralized H sub(2)O. Two groups appeared: (1) In the microflora + Protozoa units, carbon mineralization was reduced by 60% compared with the control litter. (2) In the diversified food web combinations, it became progressively higher with increasing complexity of the animal community and was enhanced by 30% compared with the control litter. This unexpected fundamental difference was explained by a change in the composition and activity of the microflora.
ISSN:0030-1299