Response of Crops to a Heat Wave Detected by using Airborne Reflectance and Chlorophyll Fluorescence Measurements Peiqi Yang, Christiaan van der Tol, Wouter Verhoef, Alexander Damm, Anke Schickling and Uwe Rascher 15-Feb-2017
Introduction June 30 th 26 o C in 2015 July 2 nd 34 o C in 2015 HyPlant 1. rapeseed, 2. corn, 3. barley 4. wheat Day 2 Day 1 Reflectance Fluorescence
Introduction The Sun Reflectance Observer Fluorescence canopy soil R reveals canopy greenness (LAI, Cab), except photosynthetic reflectance index (PRI).
1. reflection 3. absorption 2. transmission 1. reflection 3. absorption 2. transmission
F reveals photosynthetic functioning, but is superimposed by canopy structure, leaf biochemical, biophysical properties and sun-observer geometry. Remote Sensing of Fluorescence, Photosynthesis and Vegetation Status ESA-ESRIN, 24-26 Jan 2017
The Sun
Method Level 1. Fluorescence, reflectance indices (remote sensing products): SIF - ifld method Level 2. Leaf properties and canopy structure (SCOPE inversion) Numerical optimization Photosynthetic efficiency Heat dissipation Canopy structure LAI and leaf pigment concentration are assumed not changing between the two days. Level 3. Functional traits: fluorescence emission efficiency (SCOPE forward) SCOPE
Results 34 o C Fluorescence at two wavelength 687 nm and 760 nm 26 o C
Results Reflectance indices EVI and PRI
Results Leaf water content (Cw) and average leaf angles (ALA)
Results Vegetation optical contribution to the fluorescence observations
Results Fluorescence efficiency estimated from the measurements
Results Different responses of C3 and C4 crops + refers to an increase - refers to a decrease From PRI
Results Relative contribution of leaf inclination (LIDF), leaf water content (Cw), solar zenith angle, soil background to the changes in reflectance before and during the heat wave.
Results Relative contribution of vegetation optical properties and photosynthetic functional to the changes in fluorescence before and during the heat wave. Other includes the incoming light, solar angles.
Combination of R and F enables the remote detection of vegetation optical and photosynthesis functional response to environment conditions.
Thank you!!!
Meteorological data
Sampling
Reflectance
Model inversion Cost function
Model inversion
Compared with photosynthesis model
The Sun Observer Reflectance Fluorescence canopy soil Remote Sensing of Fluorescence, Photosynthesis and Vegetation Status ESA-ESRIN, 24-26 Jan 2017
Remote Sensing of Fluorescence, Photosynthesis and Vegetation Status ESA-ESRIN, 24-26 Jan 2017
Introduction June 30 th 26 C in2015 July 2 nd 34 C in 2015 1. rapeseed, 2. corn, 3. barley 4. wheat How did the crops respond to the heat wave? Using reflectance and chlorophyll fluorescence.
1. reflection 3. absorption 2. transmission Remote Sensing of Fluorescence, Photosynthesis and Vegetation Status ESA-ESRIN, 24-26 Jan 2017
1. reflection 3. absorption 2. transmission Remote Sensing of Fluorescence, Photosynthesis and Vegetation Status ESA-ESRIN, 24-26 Jan 2017
Photosynthesis Fluorescence Heat Remote Sensing of Fluorescence, Photosynthesis and Vegetation Status ESA-ESRIN, 24-26 Jan 2017
The Sun Observer canopy soil
The Sun Observer Observer canopy canopy soil soil Photosynthesis Fluorescence Heat