REFLECTANCE PRI DOES NOT EQUAL TRANSMITTANCE PRI

Vern Vanderbilt; Craig Daughtry; Robert Dahlgren

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NASA NTRS · 20205004199

REFLECTANCE PRI DOES NOT EQUAL TRANSMITTANCE PRI

Vern Vanderbilt·Craig Daughtry·Robert Dahlgren

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Abstract

Starting from leaf reflectance and transmittance measurements, we calculated two substantially different values of the Photochemical Reflectance Index (PRI) for each of 22 corn leaves having leaf chlorophyll concentrations ranging from high to low. Leaf reflectance and transmittance were measured simultaneously, precluding changes in leaf light use efficiency (LEU) between measurements. We propose the proportion of leaves reflecting v. transmitting direct beam sunlight toward a canopy reflectance sensor is a potential source of variability in estimates of canopy bidirectional PRI.

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Reflectance PRI Not Equal Transmittance

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Vern Vanderbilt, Craig Daughtry, Robert Dahlgren. 2020-09-26. REFLECTANCE PRI DOES NOT EQUAL TRANSMITTANCE PRI. https://ntrs.nasa.gov/citations/20205004199

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