Data/hora: 07/06/2024 13:20:23

Biblioteca(s): | Embrapa Amazônia Oriental.
Tipo da produção científica: | Artigo em Periódico Indexado
Circulação/Nível: | A - 1
Data corrente: | 06/02/2018
Data da última atualização: | 02/05/2018
Autoria: | WU, J.; KOBAYASHI, H.; STARK, S. C.; MENG, R.; GUAN, K.; TRAN, N. N.; GAO, S.; YANG, W.; RESTREPO-COUPE, N.; MIURA, T.; OLIVEIRA JUNIOR, R. C. de; ROGERS, A.; DYE, D. G.; NELSON, B. W.; SERBIN, S. P.; HUETE, A. R.; SALESKA, S. R.
Afiliação: | Jin Wu, University of Arizona / Brookhaven National Laboratory; Hideki Kobayashi, Japan Agency for Marine-Earth Science and Technology; Scott C. Stark, Michigan State University; Ran Meng, Brookhaven National Laboratory; Kaiyu Guan, University of Illinois at Urbana Champaign; Ngoc Nguyen Tran, University of Technology Sydney; Sicong Gao, University of Technology Sydney; Wei Yang, Chiba University; Natalia Restrepo-Coupe, University of Arizona; Tomoaki Miura, University of Havaii; RAIMUNDO COSME DE OLIVEIRA JUNIOR, CPATU; Alistair Rogers, Brookhaven National Laboratory; Dennis G. Dye, Northern Arizona University; Bruce W. Nelson, INPA; Shawn P. Serbin, Brookhaven National Laboratory; Alfredo R. Huete, University of Technology Sydney; Scott R. Saleska, University of Arizona.
Título: | Biological processes dominate seasonality of remotely sensed canopy greenness in an Amazon evergreen forest.
Ano de publicação: | 2018
Fonte/Imprenta: | New Phytologist, v. 217, n. 4, p. 1507-1520, Mar. 2018.
DOI: | 10.1111/nph.14939
Idioma: | Inglês
Conteúdo: | Satellite observations of Amazon forests show seasonal and interannual variations, but the underlying biological processes remain debated. Here we combined radiative transfer models (RTMs) with field observations of Amazon forest leaf and canopy characteristics to test three hypotheses for satellite-observed canopy reflectance seasonality: seasonal changes in leaf area index, in canopy-surface leafless crown fraction and/or in leaf demography. Canopy RTMs (PROSAIL and FLiES), driven by these three factors combined, simulated satellite-observed seasonal patterns well, explaining c. 70% of the variability in a key reflectance-based vegetation index (MAIAC EVI, which removes artifacts that would otherwise arise from clouds/aerosols and sun?sensor geometry). Leaf area index, leafless crown fraction and leaf demography independently accounted for 1, 33 and 66% of FLiES-simulated EVI seasonality, respectively. These factors also strongly influenced modeled near-infrared (NIR) reflectance, explaining why both modeled and observed EVI, which is especially sensitive to NIR, captures canopy seasonal dynamics well. Our improved analysis of canopy-scale biophysics rules out satellite artifacts as significant causes of satellite-observed seasonal patterns at this site, implying that aggregated phenology explains the larger scale remotely observed patterns. This work significantly reconciles current controversies about satellite-detected Amazon phenology, and improves our use of satellite observations to study climate?phenology relationships in the tropics.
Palavras-Chave: | Sazonalidade.
Thesagro: | Fenologia; Floresta tropical.
Categoria do assunto: | P Recursos Naturais, Ciências Ambientais e da Terra
Registro original: | Embrapa Amazônia Oriental (CPATU)
Exemplares: | CPATU - (54677-1) - UPC - AP - DD -  -  -  - DIS