Regrowth of tropical secondary forests following complete or nearly complete removal of forest vegetation actively stores carbon in aboveground biomass, partially counterbalancing carbon emissions from deforestation, forest degradation, burning of fossil fuels, and other anthropogenic sources. We estimate the age and spatial extent of lowland second-growth forests in the Latin American tropics and model their potential aboveground carbon accumulation over four decades. Our model shows that, in 2008, second-growth forests (1 to 60 years old) covered 2.4 million km2 of land (28.1%of the total study area).Over 40 years, these lands can potentially accumulate a total aboveground carbon stock of 8.48 Pg C (petagrams of carbon) in aboveground biomass via low-cost natural regeneration or assisted regeneration, corresponding to a total CO2 sequestration of 31.09 Pg CO2. This total is equivalent to carbon emissions from fossil fuel use and industrial processes in all of Latin America and the Caribbean from1993 to 2014. Ten countries account for 95% of this carbon storage potential, led by Brazil, Colombia, Mexico, and Venezuela. We model future land-use scenarios to guide national carbon mitigation policies. Permitting natural regeneration on 40% of lowland pastures potentially stores an additional 2.0 Pg C over 40 years. Our study provides information and maps to guide national-level forest-based carbon mitigation plans on the basis of estimated rates of natural regeneration and pasture abandonment. Coupled with avoided deforestation and sustainable forestmanagement, natural regeneration of second-growth forests provides a low-costmechanism that yields a high carbon sequestration potential with multiple benefits for biodiversity and ecosystem services.
Bibliographical noteFunding Information:
10SI ForestGEO, Smithsonian Tropical Research Institute, Roosevelt Avenue, 401 Balboa, Ancon, Panama. 11German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany. 12Institute for Biology, Leipzig University, Johannisallee 21, 04103 Leipzig, Germany. 13Departamento de Botânica-CCB, Universidade Federal de Pernambuco, Pernambuco, CEP 50670-901, Brazil. 14Department of Sustainability Science, El Colegio de la Frontera Sur, Av. Rancho Polígono 2-A, Ciudad Industrial, Lerma 24500, Campeche, Mexico. 15Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA 70118, USA. 16Smithsonian Tropical Research Institute, Roosevelt Avenue, 401 Balboa, Ancon, Panama. 17Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, UK. 18Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634, USA. 19Centro de Investigación Científica de Yucatán A.C. Unidad de Recursos Naturales, Calle 43 # 130, Colonia Chuburná de Hidalgo, C.P. 97200, Mérida, Yucatán, México. 20Earth and Atmospheric Sciences Department, University of Alberta, Edmonton, Alberta T6G 2EG, Canada. 21Departamento de Biologia Geral, Universidade Estadual de Montes Claros, Montes Claros, Minas Gerais, CEP 39401-089, Brazil. 22Fondo Patrimonio Natural para la Biodiversidad y Areas Protegidas, Calle 72 No. 12-65 piso 6, 110231 Bogota, Colombia. 23Biological Dynamics of Forest Fragments Project, Environmental Dynamics Research Coordination, Instituto Nacional de Pesquisas da Amazonia, Manaus, Amazonas, CEP 69067-375, Brazil. 24Centre for Crop Systems Analysis, Wageningen University, P.O. Box 430, 6700 AK Wageningen, Netherlands.