Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues
Mosses contribute an average of 20 % of boreal upland forest net primary productivity and are frequently observed to degrade slowly compared to vascular plants. If this is caused primarily by the chemical complexity of their tissues, moss decomposition could exhibit high temperature sensitivity (mea...
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Online Access: | http://www.osti.gov/servlets/purl/1506777 https://www.osti.gov/biblio/1506777 https://doi.org/10.5194/bg-15-6731-2018 |
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ftosti:oai:osti.gov:1506777 2023-07-30T04:05:04+02:00 Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues Philben, Michael Butler, Sara Billings, Sharon A. Benner, Ronald Edwards, Kate A. Ziegler, Susan E. 2023-06-29 application/pdf http://www.osti.gov/servlets/purl/1506777 https://www.osti.gov/biblio/1506777 https://doi.org/10.5194/bg-15-6731-2018 unknown http://www.osti.gov/servlets/purl/1506777 https://www.osti.gov/biblio/1506777 https://doi.org/10.5194/bg-15-6731-2018 doi:10.5194/bg-15-6731-2018 54 ENVIRONMENTAL SCIENCES 59 BASIC BIOLOGICAL SCIENCES 2023 ftosti https://doi.org/10.5194/bg-15-6731-2018 2023-07-11T09:32:38Z Mosses contribute an average of 20 % of boreal upland forest net primary productivity and are frequently observed to degrade slowly compared to vascular plants. If this is caused primarily by the chemical complexity of their tissues, moss decomposition could exhibit high temperature sensitivity (measured as Q 10 ) due to high activation energy, which would imply that soil organic carbon (SOC) stocks derived from moss remains are especially vulnerable to decomposition with warming. Alternatively, the physical structure of the moss cell-wall biochemical matrix could inhibit decomposition, resulting in low decay rates and low temperature sensitivity. We tested these hypotheses by incubating mosses collected from two boreal forests in Newfoundland, Canada, for 959 days at 5°C and 18°C, while monitoring changes in the moss tissue composition using total hydrolyzable amino acid (THAA) analysis and 13 C nuclear magnetic resonance (NMR) spectroscopy. Less than 40 % of C was respired in all incubations, revealing a large pool of apparently recalcitrant C. The decay rate of the labile fraction increased in the warmer treatment, but the total amount of C loss increased only slightly, resulting in low Q 10 values (1.23–1.33) compared to L horizon soils collected from the same forests. NMR spectra were dominated by O-alkyl C throughout the experiment, indicating the persistence of potentially labile C. The accumulation of hydroxyproline (derived primarily from plant cell-wall proteins) and aromatic C indicates the selective preservation of biochemicals associated with the moss cell wall. This was supported by scanning electron microscope (SEM) images of the moss tissues, which revealed few changes in the physical structure of the cell wall after incubation. This suggests that the moss cell-wall matrix protected labile C from microbial decomposition, accounting for the low temperature sensitivity of moss decomposition despite low decay rates. Climate drivers of moss biomass and productivity, therefore, represent a potentially ... Other/Unknown Material Newfoundland SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Canada Biogeosciences 15 21 6731 6746 |
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SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
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ftosti |
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54 ENVIRONMENTAL SCIENCES 59 BASIC BIOLOGICAL SCIENCES |
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54 ENVIRONMENTAL SCIENCES 59 BASIC BIOLOGICAL SCIENCES Philben, Michael Butler, Sara Billings, Sharon A. Benner, Ronald Edwards, Kate A. Ziegler, Susan E. Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues |
topic_facet |
54 ENVIRONMENTAL SCIENCES 59 BASIC BIOLOGICAL SCIENCES |
description |
Mosses contribute an average of 20 % of boreal upland forest net primary productivity and are frequently observed to degrade slowly compared to vascular plants. If this is caused primarily by the chemical complexity of their tissues, moss decomposition could exhibit high temperature sensitivity (measured as Q 10 ) due to high activation energy, which would imply that soil organic carbon (SOC) stocks derived from moss remains are especially vulnerable to decomposition with warming. Alternatively, the physical structure of the moss cell-wall biochemical matrix could inhibit decomposition, resulting in low decay rates and low temperature sensitivity. We tested these hypotheses by incubating mosses collected from two boreal forests in Newfoundland, Canada, for 959 days at 5°C and 18°C, while monitoring changes in the moss tissue composition using total hydrolyzable amino acid (THAA) analysis and 13 C nuclear magnetic resonance (NMR) spectroscopy. Less than 40 % of C was respired in all incubations, revealing a large pool of apparently recalcitrant C. The decay rate of the labile fraction increased in the warmer treatment, but the total amount of C loss increased only slightly, resulting in low Q 10 values (1.23–1.33) compared to L horizon soils collected from the same forests. NMR spectra were dominated by O-alkyl C throughout the experiment, indicating the persistence of potentially labile C. The accumulation of hydroxyproline (derived primarily from plant cell-wall proteins) and aromatic C indicates the selective preservation of biochemicals associated with the moss cell wall. This was supported by scanning electron microscope (SEM) images of the moss tissues, which revealed few changes in the physical structure of the cell wall after incubation. This suggests that the moss cell-wall matrix protected labile C from microbial decomposition, accounting for the low temperature sensitivity of moss decomposition despite low decay rates. Climate drivers of moss biomass and productivity, therefore, represent a potentially ... |
author |
Philben, Michael Butler, Sara Billings, Sharon A. Benner, Ronald Edwards, Kate A. Ziegler, Susan E. |
author_facet |
Philben, Michael Butler, Sara Billings, Sharon A. Benner, Ronald Edwards, Kate A. Ziegler, Susan E. |
author_sort |
Philben, Michael |
title |
Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues |
title_short |
Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues |
title_full |
Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues |
title_fullStr |
Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues |
title_full_unstemmed |
Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues |
title_sort |
biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues |
publishDate |
2023 |
url |
http://www.osti.gov/servlets/purl/1506777 https://www.osti.gov/biblio/1506777 https://doi.org/10.5194/bg-15-6731-2018 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_relation |
http://www.osti.gov/servlets/purl/1506777 https://www.osti.gov/biblio/1506777 https://doi.org/10.5194/bg-15-6731-2018 doi:10.5194/bg-15-6731-2018 |
op_doi |
https://doi.org/10.5194/bg-15-6731-2018 |
container_title |
Biogeosciences |
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15 |
container_issue |
21 |
container_start_page |
6731 |
op_container_end_page |
6746 |
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