Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure
Arctic warming accelerates snowmelt, exposing soil surfaces with shallow or no snow cover to freeze–thaw cycles (FTCs) more frequently in early spring and late autumn. FTCs influence Arctic soil C dynamics by increasing or decreasing the amount of dissolved organic carbon (DOC); however, mechanism-b...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2023
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-17-3101-2023 https://doaj.org/article/a7cc6c79e5634572b30109cb5b8e68cb |
id |
ftdoajarticles:oai:doaj.org/article:a7cc6c79e5634572b30109cb5b8e68cb |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:a7cc6c79e5634572b30109cb5b8e68cb 2023-08-27T04:07:39+02:00 Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure Y. J. Kim J. Kim J. Y. Jung 2023-07-01T00:00:00Z https://doi.org/10.5194/tc-17-3101-2023 https://doaj.org/article/a7cc6c79e5634572b30109cb5b8e68cb EN eng Copernicus Publications https://tc.copernicus.org/articles/17/3101/2023/tc-17-3101-2023.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-17-3101-2023 1994-0416 1994-0424 https://doaj.org/article/a7cc6c79e5634572b30109cb5b8e68cb The Cryosphere, Vol 17, Pp 3101-3114 (2023) Environmental sciences GE1-350 Geology QE1-996.5 article 2023 ftdoajarticles https://doi.org/10.5194/tc-17-3101-2023 2023-08-06T00:48:30Z Arctic warming accelerates snowmelt, exposing soil surfaces with shallow or no snow cover to freeze–thaw cycles (FTCs) more frequently in early spring and late autumn. FTCs influence Arctic soil C dynamics by increasing or decreasing the amount of dissolved organic carbon (DOC); however, mechanism-based explanations of DOC changes that consider other soil biogeochemical properties are limited. To understand the effects of FTCs on Arctic soil responses, we designed microcosms with surface organic soils from Alaska and investigated several soil biogeochemical changes for seven successive temperature fluctuations of freezing at − 9.0 ± 0.3 ∘ C and thawing at 6.2 ± 0.3 ∘ C for 12 h each. FTCs significantly changed the following soil variables: soil CO 2 production (CO 2 ), DOC and total dissolved nitrogen (TDN) contents, two DOC quality indices (SUVA 254 and A 365 / <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="3af55808dad7e355d8e0b0b2a0272ce7"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-17-3101-2023-ie00001.svg" width="8pt" height="14pt" src="tc-17-3101-2023-ie00001.png"/></svg:svg> A 254 ), microaggregate (53–250 µm ) distribution, and small-sized mesopore (0.2–10 µm ) proportion. Multivariate statistical analyses indicated that the FTCs improved soil structure at the scale of microaggregates and small-sized mesopores, facilitating DOC decomposition by soil microbes and changes in DOC quantity and quality by FTCs. This study showed that FTCs increased soil CO 2 production, indicating that FTCs affected DOC characteristics without negatively impacting microbial activity. Soil microaggregation enhanced by FTCs and the subsequent increase in microbial activity and small-sized pore proportion could promote DOC decomposition, decreasing the DOC quantity. This study provides a mechanism-based interpretation of how FTCs alter DOC characteristics of the organic soil in the active layer by incorporating ... Article in Journal/Newspaper Arctic The Cryosphere Alaska Directory of Open Access Journals: DOAJ Articles Arctic The Cryosphere 17 7 3101 3114 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 Y. J. Kim J. Kim J. Y. Jung Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Arctic warming accelerates snowmelt, exposing soil surfaces with shallow or no snow cover to freeze–thaw cycles (FTCs) more frequently in early spring and late autumn. FTCs influence Arctic soil C dynamics by increasing or decreasing the amount of dissolved organic carbon (DOC); however, mechanism-based explanations of DOC changes that consider other soil biogeochemical properties are limited. To understand the effects of FTCs on Arctic soil responses, we designed microcosms with surface organic soils from Alaska and investigated several soil biogeochemical changes for seven successive temperature fluctuations of freezing at − 9.0 ± 0.3 ∘ C and thawing at 6.2 ± 0.3 ∘ C for 12 h each. FTCs significantly changed the following soil variables: soil CO 2 production (CO 2 ), DOC and total dissolved nitrogen (TDN) contents, two DOC quality indices (SUVA 254 and A 365 / <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="3af55808dad7e355d8e0b0b2a0272ce7"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-17-3101-2023-ie00001.svg" width="8pt" height="14pt" src="tc-17-3101-2023-ie00001.png"/></svg:svg> A 254 ), microaggregate (53–250 µm ) distribution, and small-sized mesopore (0.2–10 µm ) proportion. Multivariate statistical analyses indicated that the FTCs improved soil structure at the scale of microaggregates and small-sized mesopores, facilitating DOC decomposition by soil microbes and changes in DOC quantity and quality by FTCs. This study showed that FTCs increased soil CO 2 production, indicating that FTCs affected DOC characteristics without negatively impacting microbial activity. Soil microaggregation enhanced by FTCs and the subsequent increase in microbial activity and small-sized pore proportion could promote DOC decomposition, decreasing the DOC quantity. This study provides a mechanism-based interpretation of how FTCs alter DOC characteristics of the organic soil in the active layer by incorporating ... |
format |
Article in Journal/Newspaper |
author |
Y. J. Kim J. Kim J. Y. Jung |
author_facet |
Y. J. Kim J. Kim J. Y. Jung |
author_sort |
Y. J. Kim |
title |
Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure |
title_short |
Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure |
title_full |
Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure |
title_fullStr |
Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure |
title_full_unstemmed |
Responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure |
title_sort |
responses of dissolved organic carbon to freeze–thaw cycles associated with the changes in microbial activity and soil structure |
publisher |
Copernicus Publications |
publishDate |
2023 |
url |
https://doi.org/10.5194/tc-17-3101-2023 https://doaj.org/article/a7cc6c79e5634572b30109cb5b8e68cb |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic The Cryosphere Alaska |
genre_facet |
Arctic The Cryosphere Alaska |
op_source |
The Cryosphere, Vol 17, Pp 3101-3114 (2023) |
op_relation |
https://tc.copernicus.org/articles/17/3101/2023/tc-17-3101-2023.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-17-3101-2023 1994-0416 1994-0424 https://doaj.org/article/a7cc6c79e5634572b30109cb5b8e68cb |
op_doi |
https://doi.org/10.5194/tc-17-3101-2023 |
container_title |
The Cryosphere |
container_volume |
17 |
container_issue |
7 |
container_start_page |
3101 |
op_container_end_page |
3114 |
_version_ |
1775348388494049280 |