Effects of Water Table Fluctuation on Greenhouse Gas Emissions from Wetland Soils in the Peruvian Amazon

• Published in: Wetlands (Wilmington, N.C.) Vol. 43; no. 6; p. 62
• Main Authors: Pärn, Jaan, Soosaar, Kaido, Schindler, Thomas, Machacova, Katerina, Muñoz, Waldemar Alegría, Fachín, Lizardo, Aspajo, José Luis Jibaja, Negron-Juarez, Robinson I., Maddison, Martin, Rengifo, Jhon, Dinis, Danika Journeth Garay, Oversluijs, Adriana Gabriela Arista, Fucos, Manuel Calixto Ávila, Vásquez, Rafael Chávez, Wampuch, Ronald Huaje, García, Edgar Peas, Sohar, Kristina, Horna, Segundo Cordova, Gómez, Tedi Pacheco, Muñoz, Jose David Urquiza, Espinoza, Rodil Tello, Mander, Ülo
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.08.2023; Springer Nature B.V; Springer
• Subjects: Biogeochemistry; Biomedical and Life Sciences; Carbon; Carbon dioxide; Cassava; Climate change; Coastal Sciences; Drawdown; Drought; Ecology; Ecosystems; Emissions; Environmental conditions; Environmental Management; ENVIRONMENTAL SCIENCES; Forests; Freshwater & Marine Ecology; greenhouse gas; Greenhouse gases; Hydrogeology; Land use; Landscape Ecology; laughing gas; Life Sciences; Methane; Nitrates; Nitrogen; Nitrous oxide; Oxygen content; Peat; peatland; Peatlands; Rain; Respiration; Slash and burn; Soil moisture; Soil surfaces; Swamps; tropical; tropics; Water table; Wetland Biogeochemistry; Wetlands; Peru; Amazon Basin; Methane; Greenhouse gas; Carbon dioxide; Nitrous oxide; Tropical; Laughing gas; Peat; Peatland; Tropics
• ISSN: 0277-5212; 1943-6246
• DOI: 10.1007/s13157-023-01709-z

Amazonian swamp forests remove large amounts of carbon dioxide (CO 2 ) but produce methane (CH 4 ). Both are important greenhouse gases (GHG). Drought and cultivation cut the CH 4 emissions but may release CO 2 . Varying oxygen content in nitrogen-rich soil produces nitrous oxide (N 2 O), which is the third most important GHG. Despite the potentially tremendous changes, GHG emissions from wetland soils under different land uses and environmental conditions have rarely been compared in the Amazon. We measured environmental characteristics, and CO 2 , CH 4 and N 2 O emissions from the soil surface with manual opaque chambers in three sites near 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 soil respiration and N 2 O emission. The peat swamp forests under slight water table drawdown emitted large amounts of CO 2 and CH 4 . A heavy post-drought shower created a hot moment of N 2 O in the pristine swamp forest, likely produced by nitrifiers. All in all, even small changes in soil moisture can create hot moments of GHG emissions from Amazonian wetland soils, and should therefore be carefully monitored.