Data/hora: 03/06/2024 13:58:33

Biblioteca(s): | Embrapa Amazônia Oriental.
Data corrente: | 02/01/2017
Data da última atualização: | 20/05/2022
Autoria: | RESTREPO-COUPE, N.; LEVINE, N. M.; CHRISTOFFERSEN, B. O.; ALBERT, L. P.; WU, J.; COSTA, M. H.; GALBRAITH, D.; IMBUZEIRO, H.; MARTINS, G.; ARAUJO, A. C. da; MALHI, Y. S.; ZENG, X.; MOORCROFT, P.; SALESKA, S. R.
Afiliação: | NATALIA RESTREPO-COUPE, University of Technology Sydney / University of Arizona; NAOMI M. LEVINE, University of Southern California / Harvard University; BRADLEY O. CHRISTOFFERSEN, University of Arizona / Los Alamos National Laboratory; LOREN P. ALBERT, University of Arizona; JIN WU, University of Arizona / Brookhaven National Lab; MARCOS H. COSTA, UFV; DAVID GALBRAITH, University of Leeds; HEWLLEY IMBUZEIRO, UFV; GIORDANE MARTINS, INPA; ALESSANDRO CARIOCA DE ARAUJO, CPATU; YADVINDER S. MALHI, University of Oxford; XUBIN ZENG, University of Arizona; PAUL MOORCROFT, Harvard University; SCOTT R. SALESKA, University of Arizona.
Título: | Do dynamic global vegetation models capture the seasonality of carbon fluxes in the Amazon basin? A data-model intercomparison.
Ano de publicação: | 2017
Fonte/Imprenta: | Global Change Biology, v. 23, n. 1, p. 191-208, Jan. 2017.
DOI: | 10.1111/gcb.13442
Idioma: | Inglês
Conteúdo: | To predict forest response to long-term climate change with high confidence requires that dynamic global vegetation models (DGVMs) be successfully tested against ecosystem response to short-term variations in environmental drivers, including regular seasonal patterns. Here, we used an integrated dataset from four forests in the Brasil flux network, spanning a range of dry-season intensities and lengths, to determine how well four state-of-the-art models (IBIS, ED2, JULES, and CLM3.5) simulated the seasonality of carbon exchanges in Amazonian tropical forests. We found that most DGVMs poorly represented the annual cycle of gross primary productivity (GPP), of photosynthetic capacity (Pc), and of other fluxes and pools. Models simulated consistent dry-season declines in GPP in the equatorial Amazon (Manaus K34, Santarem K67, and Caxiuanã CAX); a contrast to observed GPP increases. Model simulated dry-season GPP reductions were driven by an external environmental factor, ?soil water stress? and consequently by a constant or decreasing photosynthetic infrastructure (Pc), while observed dry-season GPP resulted from a combination of internal biological (leaf-flush and abscission and increased Pc) and environmental (incoming radiation) causes. Moreover, we found models generally overestimated observed seasonal net ecosystem exchange (NEE) and respiration (Re) at equatorial locations. In contrast, a southern Amazon forest (Jarú RJA) exhibited dry-season declines in GPP and Re consistent with most DGVMs simulations. While water limitation was represented in models and the primary driver of seasonal photosynthesis in southern Amazonia, changes in internal biophysical processes, light-harvesting adaptations (e.g., variations in leaf area index (LAI) and increasing leaf-level assimilation rate related to leaf demography), and allocation lags between leaf and wood, dominated equatorial Amazon carbon flux dynamics and were deficient or absent from current model formulations. Correctly simulating flux seasonality at tropical forests requires a greater understanding and the incorporation of internal biophysical mechanisms in future model developments.
Palavras-Chave: | Carbon dynamics; Dinâmica do carbono; Dynamic global vegetation models; Ecosystem–climate interactions; Florestas tropicais; Modelos dinâmicos de vegetação; Sazonalidade; Seasonality; Tropical forests phenology.
Thesagro: | Fenologia.
Thesaurus Nal: | Amazonia; eddy covariance.
Categoria do assunto: | K Ciência Florestal e Produtos de Origem Vegetal
Registro original: | Embrapa Amazônia Oriental (CPATU)
Exemplares: | CPATU - (53129-1) - UPC - AP - DD -  -  -  - DIS