Preprints
https://doi.org/10.5194/egusphere-2023-210
https://doi.org/10.5194/egusphere-2023-210
14 Feb 2023
 | 14 Feb 2023

Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau

Andres Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos Sierra

Abstract. Microbial release of CO2 from soils to the atmosphere reflects how environmental conditions affect the stability of soil organic matter (SOM), especially in massive organic-rich ecosystems like the peatlands and grasslands of the Qinghai-Tibetan Plateau (QTP). Radiocarbon (14C) is an important tracer of the global carbon cycle and can be used to understand SOM dynamics through the estimation of time lags between C fixation and respiration, often assessed with metrics such as age and transit time. In this study, we incubated peatland and grassland soils at four temperature (5, 10, 15 and 20 °C) and two water-filled pore space (WFPS) levels (60 and 95 %), and measured the 14C signature of bulk soil and respired CO2. We compare the relation between the Δ14C of the bulk soil and the Δ14CO2 of respired carbon as a function of temperature and WFPS for the two soils. To better interpret our results, we used a mathematical model to analyse how the calculated number of pools, decomposition rates of carbon (k), transfer (α) and partitioning (γ) coefficients affect the Δ14C -bulk and Δ14CO2 relation, with their respective mean age and mean transit time. From our incubations, we found that 14C from peatland was significantly more depleted (old) than from grassland soil. Our results showed that changes in temperature did not affect the Δ14C values of respired CO2 in either soil. However, changes in WFPS had a small effect on the 14C CO2 in grassland soils and a strong influence in peatland soils, where higher WFPS levels led to more depleted Δ14CO2. In our models, we observed large differences between slow and fast cycling systems, where low values of k modified Δ14C patterns due to the incorporation of 14C-bomb in the soil. Hence, the correspondence between Δ14C and age and transit time strongly depended on the internal dynamics of the soil (k, α, γ and number of pools) as well as on model structure. We conclude that the stability of carbon in these systems depends strongly on the direction of change in temperature and moisture and how it affects the rates of SOM decomposition. Finally, Δ14C modelling along with empirical data from SOM dynamics is a useful tool to improve predictions on interactions between terrestrial and atmospheric carbon.

Journal article(s) based on this preprint

18 Mar 2024
Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau
Andrés Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos A. Sierra
Biogeosciences, 21, 1277–1299, https://doi.org/10.5194/bg-21-1277-2024,https://doi.org/10.5194/bg-21-1277-2024, 2024
Short summary
Andres Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos Sierra

Interactive discussion

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-210', Anonymous Referee #1, 23 Mar 2023
    • AC1: 'Reply on RC1', Andres Tangarife-Escobar, 07 Aug 2023
  • RC2: 'Comment on egusphere-2023-210', Anonymous Referee #2, 25 Jul 2023
    • AC2: 'Reply on RC2', Andres Tangarife-Escobar, 07 Aug 2023

Interactive discussion

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-210', Anonymous Referee #1, 23 Mar 2023
    • AC1: 'Reply on RC1', Andres Tangarife-Escobar, 07 Aug 2023
  • RC2: 'Comment on egusphere-2023-210', Anonymous Referee #2, 25 Jul 2023
    • AC2: 'Reply on RC2', Andres Tangarife-Escobar, 07 Aug 2023

Peer review completion

AR: Author's response | RR: Referee report | ED: Editor decision | EF: Editorial file upload
ED: Reconsider after major revisions (13 Aug 2023) by Anja Rammig
AR by Andres Tangarife-Escobar on behalf of the Authors (28 Aug 2023)  Author's response   Author's tracked changes   Manuscript 
ED: Referee Nomination & Report Request started (12 Sep 2023) by Anja Rammig
RR by Anonymous Referee #3 (15 Dec 2023)
ED: Publish subject to minor revisions (review by editor) (09 Jan 2024) by Anja Rammig
AR by Andres Tangarife-Escobar on behalf of the Authors (23 Jan 2024)  Author's response   Author's tracked changes   Manuscript 
ED: Publish as is (29 Jan 2024) by Anja Rammig
AR by Andres Tangarife-Escobar on behalf of the Authors (29 Jan 2024)  Manuscript 

Journal article(s) based on this preprint

18 Mar 2024
Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau
Andrés Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos A. Sierra
Biogeosciences, 21, 1277–1299, https://doi.org/10.5194/bg-21-1277-2024,https://doi.org/10.5194/bg-21-1277-2024, 2024
Short summary
Andres Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos Sierra

Data sets

Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau Andres Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos Sierra https://doi.org/10.5281/zenodo.7620008

Model code and software

Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau Andres Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos Sierra https://doi.org/10.5281/zenodo.7620008

Andres Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos Sierra

Viewed

Total article views: 658 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
444 187 27 658 18 16
  • HTML: 444
  • PDF: 187
  • XML: 27
  • Total: 658
  • BibTeX: 18
  • EndNote: 16
Views and downloads (calculated since 14 Feb 2023)
Cumulative views and downloads (calculated since 14 Feb 2023)

Viewed (geographical distribution)

Total article views: 644 (including HTML, PDF, and XML) Thereof 644 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 18 Mar 2024
Download

The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.

Short summary
Soil organic matter stability depends on future temperature and precipitation scenarios. We used radiocarbon (14C) data and model predictions to understand how the transit time of carbon varies under environmental change in grasslands and peatlands. Soil moisture affected the Δ14C of peatlands while temperature did not have any influence. Our models showed the correspondence between Δ14C and transit time and could allow to understand future interactions between terrestrial and atmospheric carbon.