Preprints
https://doi.org/10.5194/bg-2021-46
https://doi.org/10.5194/bg-2021-46

  03 Mar 2021

03 Mar 2021

Review 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.

High greenhouse gas fluxes from peatlands under various disturbances in the Peruvian Amazon

Jaan Pärn1, Kaido Soosaar1, Thomas Schindler1,2, Katerina Machacova1,2, Waldemar Alegría Muñoz3, Lizardo Fachín4, José Luis Jibaja Aspajo3, Robinson I. Negron-Juarez5, Martin Maddison1, Jhon Rengifo4, Danika Journeth Garay Dinis3, Adriana Gabriela Arista Oversluijs3, Manuel Calixto Ávila Fucos3, Rafael Chávez Vásquez3, Ronal Huaje Wampuch3, Edgar Peas García3, Kristina Sohar1, Segundo Cordova Horna3, Tedi Pacheco Gómez3, Jose David Urquiza Muñoz3,6, Rodil Tello Espinoza3, and Ülo Mander1,2 Jaan Pärn et al.
  • 1Department of Geography, Institute of Ecology and Earth Sciences, University of Tartu, Estonia
  • 2Department of Ecosystem Trace Gas Exchange, Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
  • 3School of Forestry, National University of the Peruvian Amazon (UNAP), Iquitos, Peru
  • 4Peruvian Amazon Research Institute (IIAP), Iquitos, Peru
  • 5Lawrence Berkeley National Laboratory, Berkeley, CA, USA
  • 6Max-Planck Institute for Biogeochemistry, Jena, Germany

Abstract. Amazonian peat swamp forests remove large amounts of carbon dioxide (CO2) but anaerobic decomposition of the peat produces methane (CH4). Drought or cultivation cuts down on the CH4 production but may increase the CO2 emission. Varying oxygen content in nitrogen-rich peat produces nitrous oxide (N2O). Despite the potentially tremendous changes, greenhouse gas emissions from peatlands under various land uses and environmental conditions have rarely been compared in the Amazon. We measured CO2, CH4 and N2O emissions from the soil surface with manual opaque chambers, and environmental characteristics in three sites around Iquitos, Peru from September 2019 to March 2020: a pristine peat swamp forest, a young forest and a slash-and-burn manioc field. The manioc field showed moderate peat respiration and N2O emission. The swamp forests under slight water table drawdown emitted large amounts of CO2 and N2O while retaining their high CH4 emissions. Most noticeably, a heavy shower after the water-table drawdown in the pristine swamp forest created a hot moment of N2O. Nitrifier denitrification was the likely source mechanism, as we rule out nitrification and heterotrophic denitrification. We base the judgement on the lack of nitrate and oxygen, and the suppressed denitrification potential in the topsoil. Overall, our study shows that even moderate drying in Peruvian palm swamps may create a devastating feedback on climate change through CO2 and N2O emissions.

Jaan Pärn et al.

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on bg-2021-46', Yit Arn Teh, 25 Mar 2021
    • AC1: 'Reply on RC1', Jaan Pärn, 11 Jul 2021
  • RC2: 'Comment on bg-2021-46', Anonymous Referee #2, 21 Jun 2021
    • AC2: 'Reply on RC2', Jaan Pärn, 11 Jul 2021
  • RC3: 'Comment on bg-2021-46', Anonymous Referee #3, 03 Aug 2021
    • AC3: 'Reply on RC3', Jaan Pärn, 23 Aug 2021

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on bg-2021-46', Yit Arn Teh, 25 Mar 2021
    • AC1: 'Reply on RC1', Jaan Pärn, 11 Jul 2021
  • RC2: 'Comment on bg-2021-46', Anonymous Referee #2, 21 Jun 2021
    • AC2: 'Reply on RC2', Jaan Pärn, 11 Jul 2021
  • RC3: 'Comment on bg-2021-46', Anonymous Referee #3, 03 Aug 2021
    • AC3: 'Reply on RC3', Jaan Pärn, 23 Aug 2021

Jaan Pärn et al.

Jaan Pärn et al.

Viewed

Total article views: 842 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
582 243 17 842 4 7
  • HTML: 582
  • PDF: 243
  • XML: 17
  • Total: 842
  • BibTeX: 4
  • EndNote: 7
Views and downloads (calculated since 03 Mar 2021)
Cumulative views and downloads (calculated since 03 Mar 2021)

Viewed (geographical distribution)

Total article views: 761 (including HTML, PDF, and XML) Thereof 761 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 02 Dec 2021
Download
Short summary
Despite alarming forecasts for the Amazonian peat swamp forests, greenhouse gas emissions from the different peat environments have rarely been compared. We measured CO2, CH4 and N2O emissions from the soil in 3 sites around Iquitos, Peru: a pristine swamp forest, a young forest and a slash-and-burn manioc field. We saw a devastating effect on global climate from a slight water-table drawdown in the peat swamp forests, while the manioc field emitted moderate amounts of the greenhouse gases.
Altmetrics