TY - JOUR
T1 - Leaf development and demography explain photosynthetic seasonality in Amazon evergreen forests
AU - Wu, Jin
AU - Albert, Loren P.
AU - Lopes, Aline P.
AU - Restrepo-Coupe, Natalia
AU - Hayek, Matthew
AU - Wiedemann, Kenia T.
AU - Guan, Kaiyu
AU - Stark, Scott C.
AU - Christoffersen, Bradley
AU - Prohaska, Neill
AU - Tavares, Julia V.
AU - Marostica, Suelen
AU - Kobayashi, Hideki
AU - Ferreira, Mauricio L.
AU - Campos, Kleber Silva
AU - Dda Silva, Rodrigo
AU - Brando, Paulo M.
AU - Dye, Dennis G.
AU - Huxman, Travis E.
AU - Huete, Alfredo R.
AU - Nelson, Bruce W.
AU - Saleska, Scott R.
N1 - Funding Information:
Funding was provided by NSF PIRE (no. 0730305), NASA Terra-Aqua Science program (NNX11AH24G), the Agnese Nelms Haury Program in Environment and Social Justice, and the GoAmazon project, funded jointly by U.S. Department of Energy (DOE) (no. DE-SC0008383) and the Brazilian state science foundations in Sao Paulo state (FAPESP), and Amazônas state (FAPEAM). J.W. was supported by a NASA Earth and Space Science fellowship. B.C. was supported in part by DOE (BER) NGEE-Tropics projects at Los Alamos National Laboratory. We thank our GoAmazon co–principal investigators V. Ivanov, M. Ferreira, R. Oliveira, and L. Aragão for discussions, the Brazilian Large Scale Biosphere-Atmosphere experiment in Amazônia (LBA) project and A. Araujo for data from the Brazilian flux tower network, and the LBA office in Santarem for logistical support at the k67 tower site. We thank F. Luizão for sharing the litterfall data at Manaus k34 site, funded by Brazilian Long-term Ecological Research Program (PELD-Brazil). We thank the Max Planck Society, INPA, Amazonas State University, Amazonas State Government, the German Federal Ministry of Education and Research, and the Brazilian Ministry of Science Technology and Innovation for support at the ATTO tower site. Eddy flux data at k67 site are available at http://ameriflux-data.lbl. gov:8080/SitePages/siteInfo.aspx?BR-Sa1. All other data published here are available at http://dx.doi.org/10.5061/dryad.8fb47. J.W., L.P.A., and S.R.S. designed the phenology experiment and analysis. J.W.,N.R.C, K.T.W., M.H., K.S.C., B. C., R.d.S., and S.R.S. contributed to the installation, maintenance, or analysis of data of the k67 eddy flux system. J.W., N.P., M.L.F., and P.M.B. contributed to or analyzed ground-based phenology data, and J.W. and S.R.S. developed the leaf demography-ontogeny model. N.R.C. and S.RS. engineered and installed the k67 camera system, and J.W., B.W.N., A.P.L, S.M., and J.V.T. analyzed the camera-based phenology data. L.P.A. collected and analyzed leaf-level gas exchange data with advice from T.E.H. K.G. analyzed MAIAC EVI data. J.W. drafted the manuscript, and S.R.S, L.P.A, T.E.H, S.C.S, B.W.N, N.R.C, K.G., A.R.H., H.K., and D.G.D. contributed to writing the final version. The authors declare no competing financial interests.
Publisher Copyright:
© 2016 by the American Association for the Advancement of Science; all rights reserved.
PY - 2016/2/26
Y1 - 2016/2/26
N2 - In evergreen tropical forests, the extent, magnitude, and controls on photosynthetic seasonality are poorly resolved and inadequately represented in Earth system models. Combining camera observations with ecosystem carbon dioxide fluxes at forests across rainfall gradients in Amazônia, we show that aggregate canopy phenology, not seasonality of climate drivers, is the primary cause of photosynthetic seasonality in these forests. Specifically, synchronization of new leaf growth with dry season litterfall shifts canopy composition toward younger, more light-use efficient leaves, explaining large seasonal increases (~27%) in ecosystem photosynthesis. Coordinated leaf development and demography thus reconcile seemingly disparate observations at different scales and indicate that accounting for leaf-level phenology is critical for accurately simulating ecosystem-scale responses to climate change.
AB - In evergreen tropical forests, the extent, magnitude, and controls on photosynthetic seasonality are poorly resolved and inadequately represented in Earth system models. Combining camera observations with ecosystem carbon dioxide fluxes at forests across rainfall gradients in Amazônia, we show that aggregate canopy phenology, not seasonality of climate drivers, is the primary cause of photosynthetic seasonality in these forests. Specifically, synchronization of new leaf growth with dry season litterfall shifts canopy composition toward younger, more light-use efficient leaves, explaining large seasonal increases (~27%) in ecosystem photosynthesis. Coordinated leaf development and demography thus reconcile seemingly disparate observations at different scales and indicate that accounting for leaf-level phenology is critical for accurately simulating ecosystem-scale responses to climate change.
UR - http://www.scopus.com/inward/record.url?scp=84961055883&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84961055883&partnerID=8YFLogxK
U2 - 10.1126/science.aad5068
DO - 10.1126/science.aad5068
M3 - Article
C2 - 26917771
AN - SCOPUS:84961055883
SN - 0036-8075
VL - 351
SP - 972
EP - 976
JO - Science
JF - Science
IS - 6276
ER -