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Title: Limits to soil carbon stability; Deep, ancient soil carbon decomposition stimulated by new labile organic inputs

Authors:
; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1359866
Grant/Contract Number:
SC0008339
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Soil Biology and Biochemistry
Additional Journal Information:
Journal Volume: 98; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-06 09:12:09; Journal ID: ISSN 0038-0717
Publisher:
Elsevier
Country of Publication:
United Kingdom
Language:
English

Citation Formats

Bernal, Blanca, McKinley, Duncan C., Hungate, Bruce A., White, Paul M., Mozdzer, Thomas J., and Megonigal, J. Patrick. Limits to soil carbon stability; Deep, ancient soil carbon decomposition stimulated by new labile organic inputs. United Kingdom: N. p., 2016. Web. doi:10.1016/j.soilbio.2016.04.007.
Bernal, Blanca, McKinley, Duncan C., Hungate, Bruce A., White, Paul M., Mozdzer, Thomas J., & Megonigal, J. Patrick. Limits to soil carbon stability; Deep, ancient soil carbon decomposition stimulated by new labile organic inputs. United Kingdom. doi:10.1016/j.soilbio.2016.04.007.
Bernal, Blanca, McKinley, Duncan C., Hungate, Bruce A., White, Paul M., Mozdzer, Thomas J., and Megonigal, J. Patrick. 2016. "Limits to soil carbon stability; Deep, ancient soil carbon decomposition stimulated by new labile organic inputs". United Kingdom. doi:10.1016/j.soilbio.2016.04.007.
@article{osti_1359866,
title = {Limits to soil carbon stability; Deep, ancient soil carbon decomposition stimulated by new labile organic inputs},
author = {Bernal, Blanca and McKinley, Duncan C. and Hungate, Bruce A. and White, Paul M. and Mozdzer, Thomas J. and Megonigal, J. Patrick},
abstractNote = {},
doi = {10.1016/j.soilbio.2016.04.007},
journal = {Soil Biology and Biochemistry},
number = C,
volume = 98,
place = {United Kingdom},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.soilbio.2016.04.007

Citation Metrics:
Cited by: 3works
Citation information provided by
Web of Science

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  • Root carbon (C) inputs may regulate decomposition rates in soil, and in this study we ask: how do labile C inputs regulate decomposition of plant residues, and soil microbial communities? In a 14 d laboratory incubation, we added C compounds often found in root exudates in seven different concentrations (0, 0.7, 1.4, 3.6, 7.2, 14.4 and 21.7 mg C g{sup -1} soil) to soils amended with and without {sup 13}C-labeled plant residue. We measured CO{sub 2} respiration and shifts in relative fungal and bacterial rRNA gene copy numbers using quantitative polymerase chain reaction (qPCR). Increased labile C input enhanced totalmore » C respiration, but only addition of C at low concentrations (0.7 mg C g{sup -1}) stimulated plant residue decomposition (+2%). Intermediate concentrations (1.4, 3.6 mg C g{sup -1}) had no impact on plant residue decomposition, while greater concentrations of C (> 7.2 mg C g{sup -1}) reduced decomposition (-50%). Concurrently, high exudate concentrations (> 3.6 mg C g{sup -1}) increased fungal and bacterial gene copy numbers, whereas low exudate concentrations (< 3.6 mg C g{sup -1}) increased metabolic activity rather than gene copy numbers. These results underscore that labile soil C inputs can regulate decomposition of more recalcitrant soil C by controlling the activity and relative abundance of fungi and bacteria.« less
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