Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2025610 | Soil Biology and Biochemistry | 2009 | 6 Pages |
Abstract
Despite its potential impact on soil carbon flow, few studies have attempted to quantify the effects of elevated carbon dioxide (CO2) on production of exudates by mycorrhizal plants. In this study we quantified low molecular weight (LMW) organic compounds exuded by non-mycorrhizal (NM) and ectomycorrhizal (ECM) plants in relation to exposure to elevated CO2. Scots pine seedlings, either colonized by one of eight different ECM fungi or non-mycorrhizal (NM), were exposed to either ambient (350Â ppm) or elevated (700Â ppm) concentrations of CO2. Exudation of LMW organic acids (LMWOAs), amino acids, dissolved monosaccharides and total dissolved organic carbon (DOC) was determined and exudation rates were calculated per g root and fungal dry mass. CO2 had a significant impact on exudation. Under elevated CO2, exudation of total LMWOAs increased by 120-160%, amino acids by 250%, dissolved monosaccharides by 130-270% and DOC by 180-220% compared to ambient CO2 treatment. Net CO2 assimilation rates increased significantly by 41-47% for seedlings exposed to elevated CO2. Exuded C calculated as a percentage of assimilated CO2 increased by 41-88% in the elevated CO2 treatment compared to ambient CO2 treatment.
Related Topics
Life Sciences
Agricultural and Biological Sciences
Soil Science
Authors
Emma M. Johansson, Petra M.A. Fransson, Roger D. Finlay, Patrick A.W. van Hees,