Artigo

The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models

There is large uncertainty whether Amazon forests will remain a carbon sink as atmospheric CO2 increases. Hence, we simulated an old-growth tropical forest using six versions of four terrestrial models differing in scale of vegetation structure and representation of biogeochemical (BGC) cycling, all...

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Autor principal: Holm, Jennifer A.
Outros Autores: G, Knox, Ryan, Zhu, Qing, Fisher, Rosie A., Koven, Charles D., Nogueira Lima, Adriano J., Riley, William J., Longo, Marcos, Negrón-Juárez, Robinson I., Araüjo, Alessandro Carioca de, Kueppers, Lara M., Moorcroft, Paul R., Higuchi, Niro, Chambers, Jeffrey Quintin
Grau: Artigo
Idioma: English
Publicado em: Journal of Geophysical Research: Biogeosciences 2020
Assuntos:
Acesso em linha: https://repositorio.inpa.gov.br/handle/1/15453
id oai:repositorio:1-15453
recordtype dspace
spelling oai:repositorio:1-15453 The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models Holm, Jennifer A. G, Knox, Ryan Zhu, Qing Fisher, Rosie A. Koven, Charles D. Nogueira Lima, Adriano J. Riley, William J. Longo, Marcos Negrón-Juárez, Robinson I. Araüjo, Alessandro Carioca de Kueppers, Lara M. Moorcroft, Paul R. Higuchi, Niro Chambers, Jeffrey Quintin Annual Variation Biogeochemical Cycle Biomass Biomass Allocation Carbon Sink Density Dependence Eddy Covariance Phosphorus Tropical Forest Vegetation Structure There is large uncertainty whether Amazon forests will remain a carbon sink as atmospheric CO2 increases. Hence, we simulated an old-growth tropical forest using six versions of four terrestrial models differing in scale of vegetation structure and representation of biogeochemical (BGC) cycling, all driven with CO2 forcing from the preindustrial period to 2100. The models were benchmarked against tree inventory and eddy covariance data from a Brazilian site for present-day predictions. All models predicted positive vegetation growth that outpaced mortality, leading to continual increases in present-day biomass accumulation. Notably, the two vegetation demographic models (VDMs) (ED2 and ELM-FATES) always predicted positive stem diameter growth in all size classes. The field data, however, indicated that a quarter of canopy trees didn't grow over the 15-year period, and while high interannual variation existed, biomass change was near neutral. With a doubling of CO2, three of the four models predicted an appreciable biomass sink (0.77 to 1.24 Mg ha−1 year−1). ELMv1-ECA, the only model used here that includes phosphorus constraints, predicted the lowest biomass sink relative to initial biomass stocks (+21%), lower than the other BGC model, CLM5 (+48%). Models projections differed primarily through variations in nutrient constraints, then carbon allocation, initial biomass, and density-dependent mortality. The VDM's performance was similar or better than the BGC models run in carbon-only mode, suggesting that nutrient competition in VDMs will improve predictions. We demonstrate that VDMs are comparable to nondemographic (i.e., “big-leaf”) models but also include finer scale demography and competition that can be evaluated against field observations. ©2020. The Authors. 2020-05-14T14:27:39Z 2020-05-14T14:27:39Z 2020 Artigo https://repositorio.inpa.gov.br/handle/1/15453 10.1029/2019JG005500 en Volume 125, Número 3 Attribution-NonCommercial-NoDerivs 3.0 Brazil http://creativecommons.org/licenses/by-nc-nd/3.0/br/ application/pdf Journal of Geophysical Research: Biogeosciences
institution Instituto Nacional de Pesquisas da Amazônia - Repositório Institucional
collection INPA-RI
language English
topic Annual Variation
Biogeochemical Cycle
Biomass
Biomass Allocation
Carbon Sink
Density Dependence
Eddy Covariance
Phosphorus
Tropical Forest
Vegetation Structure
spellingShingle Annual Variation
Biogeochemical Cycle
Biomass
Biomass Allocation
Carbon Sink
Density Dependence
Eddy Covariance
Phosphorus
Tropical Forest
Vegetation Structure
Holm, Jennifer A.
The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models
topic_facet Annual Variation
Biogeochemical Cycle
Biomass
Biomass Allocation
Carbon Sink
Density Dependence
Eddy Covariance
Phosphorus
Tropical Forest
Vegetation Structure
description There is large uncertainty whether Amazon forests will remain a carbon sink as atmospheric CO2 increases. Hence, we simulated an old-growth tropical forest using six versions of four terrestrial models differing in scale of vegetation structure and representation of biogeochemical (BGC) cycling, all driven with CO2 forcing from the preindustrial period to 2100. The models were benchmarked against tree inventory and eddy covariance data from a Brazilian site for present-day predictions. All models predicted positive vegetation growth that outpaced mortality, leading to continual increases in present-day biomass accumulation. Notably, the two vegetation demographic models (VDMs) (ED2 and ELM-FATES) always predicted positive stem diameter growth in all size classes. The field data, however, indicated that a quarter of canopy trees didn't grow over the 15-year period, and while high interannual variation existed, biomass change was near neutral. With a doubling of CO2, three of the four models predicted an appreciable biomass sink (0.77 to 1.24 Mg ha−1 year−1). ELMv1-ECA, the only model used here that includes phosphorus constraints, predicted the lowest biomass sink relative to initial biomass stocks (+21%), lower than the other BGC model, CLM5 (+48%). Models projections differed primarily through variations in nutrient constraints, then carbon allocation, initial biomass, and density-dependent mortality. The VDM's performance was similar or better than the BGC models run in carbon-only mode, suggesting that nutrient competition in VDMs will improve predictions. We demonstrate that VDMs are comparable to nondemographic (i.e., “big-leaf”) models but also include finer scale demography and competition that can be evaluated against field observations. ©2020. The Authors.
format Artigo
author Holm, Jennifer A.
author2 G, Knox, Ryan
Zhu, Qing
Fisher, Rosie A.
Koven, Charles D.
Nogueira Lima, Adriano J.
Riley, William J.
Longo, Marcos
Negrón-Juárez, Robinson I.
Araüjo, Alessandro Carioca de
Kueppers, Lara M.
Moorcroft, Paul R.
Higuchi, Niro
Chambers, Jeffrey Quintin
author2Str G, Knox, Ryan
Zhu, Qing
Fisher, Rosie A.
Koven, Charles D.
Nogueira Lima, Adriano J.
Riley, William J.
Longo, Marcos
Negrón-Juárez, Robinson I.
Araüjo, Alessandro Carioca de
Kueppers, Lara M.
Moorcroft, Paul R.
Higuchi, Niro
Chambers, Jeffrey Quintin
title The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models
title_short The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models
title_full The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models
title_fullStr The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models
title_full_unstemmed The Central Amazon Biomass Sink Under Current and Future Atmospheric CO2: Predictions From Big-Leaf and Demographic Vegetation Models
title_sort central amazon biomass sink under current and future atmospheric co2: predictions from big-leaf and demographic vegetation models
publisher Journal of Geophysical Research: Biogeosciences
publishDate 2020
url https://repositorio.inpa.gov.br/handle/1/15453
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score 11.755432