1. Introduction
FluoreSENSTM 10 is a system that measures sun-induced chlorophyll fluorescence (SIF) in plants
during photosynthesis by collecting downwelling irradiance and upwelling reflected solar
radiation signals from the vegetation required for SIF retrieval. The system includes a high-
resolution spectrometer QE Pro (Ocean Insight, Largo, FL, USA) that measures radiation signals
between 650 and 800 nm, observing the SIF signal within the O2A and O2B oxygen absorption
bands. To perform these measurements, the FluoreSENS 10 uses a fiber optic cable, motor, and
data logger.
NOTE:
A second Flame spectrometer for measuring vegetation indices that covers the range from
350 to 1000 nm can also be added.
The main potential application of FluoreSENS 10, when combined with an eddy covariance
system, is to estimate gross primary productivity (GPP) of CO2and assist in partitioning the net
ecosystem exchange of carbon dioxide into component fluxes. It can also be used as a
standalone system in monitoring vegetation health, performing stress monitoring, detecting
early stress in crops and vegetation, and providing advanced warning for drought and fire risk
assessment.
The principal design of the system was led by Dr. Lianhong Gu of the Oak Ridge National
Laboratory (see Licensed materials [p. 37] and References [p. 38]). Several component
modifications and/or selections were made specifically for FluoreSENS 10 in order to lower costs,
improve space management, improve manufacturability, meet required safety and EMI
compliance, and improve the movement of the fiber optic cables.
2. Precautions
lREAD AND UNDERSTAND the Safety section at the back of this manual.
lThe FluoreSENS 10 system has a heavy enclosure that houses highly sensitive and precise
spectrometer(s). As it is a precision scientific instrument, it must be handled with care.
lDO NOT BEND the optical fibers below a radius of 8 cm. A lower radius will alter the
calibration, and a narrow bending can break the fiber.
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