Plant functional traits and canopy structure control the relationship between photosynthetic CO2uptake and far-red sun-induced fluorescence in a Mediterranean grassland under different nutrient availability.
Sun-induced fluorescence (SIF) in the far-red region provides a new noninvasive measurement approach that has the potential to quantify dynamic changes in light-use efficiency and gross primary production (GPP). However, the mechanistic link between GPP and SIF is not completely understood. We analyzed the structural and functional factors controlling the emission of SIF at 760 nm (F760) in a Mediterranean grassland manipulated with nutrient addition of nitrogen (N), phosphorous (P) or nitrogen-phosphorous (NP). Using the soil-canopy observation of photosynthesis and energy (SCOPE) model, we investigated how nutrient-induced changes in canopy structure (i.e. changes in plant forms abundance that influence leaf inclination distribution function, LIDF) and functional traits (e.g. N content in dry mass of leaves, N%, Chlorophyll a+b concentration (Cab) and maximum carboxylation capacity (Vcmax)) affected the observed linear relationship between F760and GPP. We conclude that the addition of nutrients imposed a change in the abundance of different plant forms and biochemistry of the canopy that controls F760. Changes in canopy structure mainly control the GPP-F760relationship, with a secondary effect of Cab and Vcmax. In order to exploit F760data to model GPP at the global/regional scale, canopy structural variability, biodiversity and functional traits are important factors that have to be considered.
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Mirco
M
Migliavacca
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Oscar
O
Perez-Priego
University of Milano Bicocca, Piazza della Scienza 1, Milan, 20126, Italy.
Micol
M
Rossini
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Tarek S
TS
El-Madany
INDEHESA-Forest Research Group, Universidad de Extremadura, Plasencia, 10600, Spain.
Gerardo
G
Moreno
Department of Water Resources, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Enschede, 7500 AE, the Netherlands.
Christiaan
C
van der Tol
Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, Leo-Brandt-Str., Jülich, 52425, Germany.
Uwe
U
Rascher
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Anna
A
Berninger
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Verena
V
Bessenbacher
Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, Leo-Brandt-Str., Jülich, 52425, Germany.
Andreas
A
Burkart
Fundación Centro de Estudios Ambientales del Mediterráneo (CEAM), Valencia, 46980, Spain.
Arnaud
A
Carrara
International Livestock Research Institute, Naivasha Rd, Nairobi, 30709, Kenya.
Francesco
F
Fava
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.|State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Jin-Hong
JH
Guan
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Tiana W
TW
Hammer
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Kathrin
K
Henkel
INDEHESA-Forest Research Group, Universidad de Extremadura, Plasencia, 10600, Spain.
Enrique
E
Juarez-Alcalde
University of Milano Bicocca, Piazza della Scienza 1, Milan, 20126, Italy.
Tommaso
T
Julitta
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Olaf
O
Kolle
Environmental Remote Sensing and Spectroscopy Laboratory (SpecLab), Institute of Economics, Geography and Demography (IEGD), Spanish National Research Council (CSIC), Albasanz 26-28, Madrid, 28037, Spain.
M Pilar
MP
Martín
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Talie
T
Musavi
Environmental Remote Sensing and Spectroscopy Laboratory (SpecLab), Institute of Economics, Geography and Demography (IEGD), Spanish National Research Council (CSIC), Albasanz 26-28, Madrid, 28037, Spain.
Javier
J
Pacheco-Labrador
INDEHESA-Forest Research Group, Universidad de Extremadura, Plasencia, 10600, Spain.
Andrea
A
Pérez-Burgueño
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Thomas
T
Wutzler
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Sönke
http://orcid.org/0000-0001-5602-7956
S
Zaehle
Max Planck Institute for Biogeochemistry, Hans Knöll Straße 10, Jena, D-07745, Germany.
Markus
M
Reichstein
D002245:Carbon Dioxide / Q000378:metabolism*; D003198:Computer Simulation; D065948:Grassland; D019083:Mediterranean Region; D009584:Nitrogen / Q000494:pharmacology*; D010758:Phosphorus / Q000494:pharmacology*; D010788:Photosynthesis / Q000187:drug effects; D018515:Plant Leaves / Q000033:anatomy & histology* / Q000187:drug effects / Q000502:physiology; D019655:Quantitative Trait, Heritable; D012621:Seasons; D013050:Spectrometry, Fluorescence; D013472:Sunlight
D002245:Carbon Dioxide; D010758:Phosphorus; D009584:Nitrogen
canopy structure; far-red sun-induced fluorescence; functional traits; gross primary productivity (GPP); leaf inclination distribution function; nutrient manipulation; soil-canopy observation of photosynthesis and energy (SCOPE) model