Preprints
https://doi.org/10.5194/bg-2022-47
https://doi.org/10.5194/bg-2022-47
 
21 Feb 2022
21 Feb 2022
Status: this discussion paper is a preprint. It has been under review for the journal Biogeosciences (BG). The manuscript was not accepted for further review after discussion.

Recent significant decline of strong carbon peat accumulation rates in tropical Andes related to climate change and glacier retreat

Romina Llanos1, Patricia Moreira-Turcq1,2, Bruno Turcq3, Raúl Espinoza Villar1,4, Yizet Huaman4, Thomas Condom5, and Bram Willems4 Romina Llanos et al.
  • 1Universidad Nacional Agraria La Molina (UNALM), Lima, 15012, Peru
  • 2Institut de Recherche pour le Développement (IRD), Géosciences Environnement Toulouse (GET), UMR 5563, Toulouse, France
  • 3Institut de Recherche pour le Développement (IRD), LOCEAN/IPSL-Sorbonne Université, Bondy, 93141, France
  • 4Centro de Competencia del Agua (CCA), Programa Agua–Andes, Lima, 15086, Peru
  • 5Université Grenoble Alpes, IRD, CNRS, IGE–UMR 5001, Grenoble, France

Abstract. Climate change has altered precipitation and temperature patterns in the tropical Andes. As a result, tropical glaciers have retreated significantly over the past 50 years and have even disappeared in some areas. Andean peatlands, one of the most important Andean carbon reservoirs, also seem to be affected by these climate changes, since glaciers have been recognized as one of their vital water sources. Here, we point out the important role of Andean peatlands on carbon accumulation rates (CAR), one of the highest in the world, and the impact of climate on carbon storage over the last 65 years, using four peat cores. The peat cores were radiocarbon-dated and ages were post-bomb calibrated and chronological models indicated basal ages (30 cm depth) ranging from 1957 to 1972 CE, where accumulation rates reached up 1.7 cm yr−1. For both peatlands, carbon accumulation rates are high (mean of 470 and 220 g C m−2 yr−1 at APA 1 and APA 2 sites, respectively) and can reach up to 1010 g C m−2 yr−1. Distichia muscoides is the dominant species in the Peruvian Central Andes peatlands and the high CAR, among other factors, is a characteristic of this species. Our results point out that a marked decrease of CAR after the early 1980s at both peatlands is likely related to an increase in annual temperature, which is responsible for the retreat of glaciers. We use a new high-resolution proxy (Skrzypek et al., 2011) based on the δ13C of Distichia along the cores to evaluate the temperature variability at the site. We observed a general trend of increase in the reconstructed temperature from both studied peatlands from 1.9 to 2 ºC for the period 1970–2015 CE. Comparison with air temperature data from the NCEP-NCAR reanalysis for the higher resolution cores shows a good relationship and an increase of 2.15 °C for the same period. Temperature increase may directly affect CAR by an increase in organic matter degradation rates. The decrease in CAR during the period of study may also be due to a decrease in melt water inflow generated by the retreat of glaciers that have almost disappeared today in the catchments as a consequence of regional warming. Our findings emphasize that marked changes in carbon accumulation rates demonstrate the high ecological sensitivity of tropical high-Andean peatlands, endangering their outstanding role in the regional (and even global) C cycle as large C sinks that contribute to the mitigation of global climate change.

Romina Llanos et al.

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on bg-2022-47', Anonymous Referee #1, 10 Mar 2022
    • AC1: 'Reply on RC1', Romina Llanos, 01 Jun 2022
  • RC2: 'Comment on bg-2022-47', Anonymous Referee #2, 14 Mar 2022
    • AC2: 'Reply on RC2', Romina Llanos, 01 Jun 2022
  • RC3: 'Comment on bg-2022-47', Anonymous Referee #3, 14 Mar 2022
    • AC3: 'Reply on RC3', Romina Llanos, 01 Jun 2022
  • RC4: 'Comment on bg-2022-47', Anonymous Referee #4, 01 Apr 2022
    • AC4: 'Reply on RC4', Romina Llanos, 01 Jun 2022

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on bg-2022-47', Anonymous Referee #1, 10 Mar 2022
    • AC1: 'Reply on RC1', Romina Llanos, 01 Jun 2022
  • RC2: 'Comment on bg-2022-47', Anonymous Referee #2, 14 Mar 2022
    • AC2: 'Reply on RC2', Romina Llanos, 01 Jun 2022
  • RC3: 'Comment on bg-2022-47', Anonymous Referee #3, 14 Mar 2022
    • AC3: 'Reply on RC3', Romina Llanos, 01 Jun 2022
  • RC4: 'Comment on bg-2022-47', Anonymous Referee #4, 01 Apr 2022
    • AC4: 'Reply on RC4', Romina Llanos, 01 Jun 2022

Romina Llanos et al.

Romina Llanos et al.

Viewed

Total article views: 802 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
564 210 28 802 46 14 13
  • HTML: 564
  • PDF: 210
  • XML: 28
  • Total: 802
  • Supplement: 46
  • BibTeX: 14
  • EndNote: 13
Views and downloads (calculated since 21 Feb 2022)
Cumulative views and downloads (calculated since 21 Feb 2022)

Viewed (geographical distribution)

Total article views: 750 (including HTML, PDF, and XML) Thereof 750 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Discussed

Latest update: 14 Nov 2022
Download
Short summary
Our results highlight a marked decrease of high carbon accumulation rates in Andean peatlands over the last decades due to the diminution in melt water inflow generated by the retreat of glaciers as a consequence of regional warming. These marked changes stress the high ecological sensitivity of these peatlands, endangering their outstanding role in the regional (and even global) C cycle as large C sinks that contribute to the mitigation of global climate change.
Altmetrics