Estimating the multi-decadal carbon deficit of burned Amazonian forests

Published in Environmental Research Letters
Authors

Camila V J Silva, Luiz E O C Aragão, Paul J Young, Fernando Espirito-Santo, Erika Berenguer, Liana O Anderson, Izaias Brasil, Aline Pontes-Lopes, Joice Ferreira, Kieran Withey, Filipe França, Paulo M L A Graça, Leticia Kirsten, Haron Xaud, Cleber Salimon, Marcos A Scaranello, Bruno Castro, Marina Seixas, Renato Farias and Jos Barlow

Publication year 2020
DOI https://doi.org/10.1088/1748-9326/abb62c
Affiliations
  • Lancaster Environment Centre (LEC), Lancaster University, United Kingdom
  • National Institute for Space Research (INPE), São José dos Campos, Brazil
  • College of Life and Environmental Sciences, University of Exeter, United Kingdom
  • Centre of Excellence for Environmental Data Science (CEEDS), Lancaster University, United Kingdom
  • Leicester Institute of Space and Earth Observation (LISEO), University of Leicester, United Kingdom
  • Environmental Change Institute, University of Oxford, United Kingdom
  • National Centre for Monitoring and Early Warning of Natural Disaster (CEMADEN), São José dos Campos, Brazil
  • Rede de Biodiversidade e Biotecnologia da Amazônia Legal (BIONORTE), Universidade Estadual do Maranhão, São Luiz, Brazil
  • Brazilian Agricultural Research Corporation, Embrapa Amazônia Oriental, Belém, Brazil
  • National Institute for Research in Amazonia (INPA), Manaus, Brazil
  • Brazilian Agricultural Research Corporation, Embrapa Roraima, Brazil
  • Universidade Estadual da Paraíba, Centro de Ciências Biológicas e Sociais Aplicadas (CCBSA), João Pessoa, Brazil
  • EMBRAPA Informática Agropecuária, Campinas, Brazil
  • Instituto de Manejo e Certificação Florestal e Agrícola (IMAFLORA), Piracicaba, Brazil
  • Instituto Centro de Vida, Alta Floresta, Brazil
  • Federal University of Lavras, Minas Gerais, Brazil
IAI Program
  • CNPq 574008/2008-0, 458022/2013-6, 305054/2016- 3, 400640/2012-0, 309247/2016-0, CNPq-CAPES 441659/2016-0 [PELD-RAS], CNPq-PrevFogoIBAMA 441949/2018-5 [SEM-FLAMA],
  • 442650/2018-3 [ACREQUEIMADAS], MCIC-CNPq 420254/2018-8 [RESFLORA]
  • FAPESP 2015/50392-8, 2018/15001-6, 2016/21043-8 [ARBOLES]
  • Embrapa SEG:02.08.06.005.00 The Nature Conservancy&mdash Brasil
  • CAPES scholarships, the UK Darwin Initiative 17-023
  • NERC NE/F01614X/1 NE/G000816/1 NE/F015356/2 NE/l018123/1 NE/K016431/1 NE/P004512/1 NE/N012542/1, H2020-MSCARISE (691053-ODYSSEA)
  • the Climate and Biodiversity Initiative of BNP Paribas Foundation (project BIOCLIMATE)
  • the Inter-American Institute for Global Change Research (IAI) SGP-HW0016 [MAP-FIRES]
IAI Project SGP-HW0016
Keywords
PDFEstimating the multi-decadal carbon deficit of burned Amazonian.pdf

Abstract

Wildfires in humid tropical forests have become more common in recent years, increasing the rates of tree mortality in forests that have not co-evolved with fire. Estimating carbon emissions from these wildfires is complex. Current approaches rely on estimates of committed emissions based on static emission factors through time and space, yet these emissions cannot be assigned to specific years, and thus are not comparable with other temporally-explicit emission sources. Moreover, committed emissions are gross estimates, whereas the long-term consequences of wildfires require an understanding of net emissions that accounts for post-fire uptake of CO2. Here, using a 30 year wildfire chronosequence from across the Brazilian Amazon, we calculate net CO2 emissions from Amazon wildfires by developing statistical models comparing post-fire changes in stem mortality, necromass decomposition and vegetation growth with unburned forest plots sampled at the same time. Over the 30 yr time period, gross emissions from combustion during the fire and subsequent tree mortality and decomposition were equivalent to 126.1 Mg CO2 ha&minus1 of which 73% (92.4 Mg CO2 ha&minus1) resulted from mortality and decomposition. These emissions were only partially offset by forest growth, with an estimated CO2 uptake of 45.0 Mg ha&minus1over the same time period. Our analysis allowed us to assign emissions and growth across years, revealing that net annual emissions peak 4 yr after forest fires. At present, Brazil's National Determined Contribution (NDC) for emissions fails to consider forest fires as a significant source, even though these are likely to make a substantial and long-term impact on the net carbon balance of Amazonia. Considering long-term post-fire necromass decomposition and vegetation regrowth is crucial for improving global carbon budget estimates and national greenhouse gases (GHG) inventories for tropical forest countries.