@Article{AguilosSBHCCWZTB:2018:InSeVa,
author = "Aguilos, Maricar and Stahl, Cl{\'e}ment and Burban, Benoit and
H{\'e}rault, Bruno and Courtois, Elodie and Coste, Sabrina and
Wagner, Fabien Hubert and Ziegler, Camille and Takagi, Kentaro and
Bonal, Damien",
affiliation = "{Universit{\'e} des Antilles} and {Universit{\'e} des Antilles}
and {Universit{\'e} des Antilles} and {Universit{\'e} de
Montpellier} and {Universit{\'e} de Guyane} and {Universit{\'e}
des Antilles} and {Instituto Nacional de Pesquisas Espaciais
(INPE)} and {Universit{\'e} des Antilles} and {Hokkaido
University}",
title = "Interannual and seasonal variations in ecosystem transpiration and
water use efficiency in a tropical rainforest",
journal = "Forests",
year = "2018",
volume = "10",
number = "1",
month = "Dec.",
keywords = "tropical rainforest, evapotranspiration, water use efficiency,
drought, radiation.",
abstract = "Warmer and drier climates over Amazonia have been predicted for
the next century with expected changes in regional water and
carbon cycles. We examined the impact of interannual and seasonal
variations in climate conditions on ecosystem-level
evapotranspiration (ET) and water use efficiency (WUE) to
determine key climatic drivers and anticipate the response of
these ecosystems to climate change. We used daily climate and
eddyflux data recorded at the Guyaflux site in French Guiana from
2004 to 2014. ET and WUE exhibited weak interannual variability.
The main climatic driver of ET and WUE was global radiation (Rg),
but relative extractable water (REW) and soil temperature (Ts) did
also contribute. At the seasonal scale, ET and WUE showed a modal
pattern driven by Rg, with maximum values for ET in July and
August and for WUE at the beginning of the year. By removing
radiation effects during water depleted periods, we showed that
soil water stress strongly reduced ET. In contrast, drought
conditions enhanced radiation-normalized WUE in almost all the
years, suggesting that the lack of soil water had a more severe
effect on ecosystem evapotranspiration than on photosynthesis. Our
results are of major concern for tropical ecosystem modeling
because they suggest that under future climate conditions,
tropical forest ecosystems will be able to simultaneously adjust
CO2 and H2O fluxes. Yet, for tropical forests under future
conditions, the direction of change in WUE at the ecosystem scale
is hard to predict, since the impact of radiation on WUE is
counterbalanced by adjustments to soil water limitations.
Developing mechanistic models that fully integrate the processes
associated with CO2 and H2O flux control should help researchers
understand and simulate future functional adjustments in these
ecosystems.",
doi = "10.3390/f10010014",
url = "http://dx.doi.org/10.3390/f10010014",
issn = "1999-4907",
language = "en",
targetfile = "aguilos_interannual.pdf",
urlaccessdate = "19 abr. 2024"
}