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Title: An Unmanned Aerial System (UAS) for concurrent measurements of solar-induced chlorophyll fluorescence and hyperspectral reflectance toward improving crop monitoring

Journal Article · · Agricultural and Forest Meteorology
 [1];  [2]; ORCiD logo [1];  [3]; ORCiD logo [3];  [4];  [1]
  1. Cornell Univ., Ithaca, NY (United States). School of Integrative Plant Science
  2. Cornell Univ., Ithaca, NY (United States). School of Integrative Plant Science; Zhejiang Univ., Hangzhou (China). College of Biosystems Engineering and Food Science
  3. Cornell Univ., Ithaca, NY (United States). Dept. of Electrical and Computer Engineering
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division and Climate Change Inst.

Unmanned aerial system (UAS)-based remote sensing can provide high spatial- and temporal-resolution crop monitoring for precision management. Existing crop monitoring UAS primarily use conventional techniques such as multi-spectral broadband vegetation indices (VIs) to track canopy structure/biomass. Recently developed lightweight hyperspectral sensors can track crop physiology and performance via complementary signals such as solar-induced chlorophyll fluorescence (SIF) and photochemical reflectance index (PRI) that can be derived from hyperspectral reflectance. However, few existing UAS can acquire high-quality SIF and hyperspectral reflectance. Here, we designed a novel UAS that simultaneously captures far-red SIF and hyperspectral reflectance, using a single bifurcated fiber and motorized arm to measure downwelling and upwelling irradiance. The UAS was tested over (1) a heterogeneous corn field with spatially varying crop yield potential and (2) a set of soybean and corn plots under differing nutrient treatments. Our UAS can maintain stability under low-to-moderate winds (2–3 m/s) with <0.4 m geolocation accuracy, <0.1 m altitude drift, and <1.5° error of the fiber optic from nadir position during scanning. Weekly seasonal campaigns reveal that SIF outperforms conventional VIs such as the normalized difference vegetation index (NDVI) for distinguishing plots with different crop yield potential, especially after canopy closure when NDVI tends to saturate. The UAS can capture the diurnal dynamics of SIF and PRI for both corn and soybean. At the seasonal scale, SIF acquired from the UAS correlates well with that from a fixed SIF tower system (R2 = 0.81), which measured the same target albeit with different footprints, demonstrating the capability of UAS in characterizing the seasonal progression of crop activity. In conclusion, our newly developed UAS provides high-quality SIF and hyperspectral reflectance, facilitating mechanistic understanding of the physiological control on photosynthesis dynamics. Our findings also imply that this UAS could enable extension of fixed tower-based systems to monitor multiple targets from diurnal to seasonal scales and improve monitoring of heterogeneous fields.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER); USDA; Chinese Scholarship Council; United States - Israel Binational Agricultural Research and Development (BARD) Fund
Grant/Contract Number:
AC05-00OR22725; 2018­-67012-27985; 1014740; 201806320111; FI-576-18
OSTI ID:
1659560
Journal Information:
Agricultural and Forest Meteorology, Vol. 294; ISSN 0168-1923
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

References (74)

Operation of the xanthophyll cycle in higher plants in response to diurnal changes in incident sunlight journal February 1992
Spectroscopy of canopy chemicals in humid tropical forests journal December 2011
Using spectral chlorophyll fluorescence and the photochemical reflectance index to predict physiological dynamics journal April 2016
Chlorophyll Fluorescence: A Probe of Photosynthesis In Vivo journal June 2008
Thermal and Narrowband Multispectral Remote Sensing for Vegetation Monitoring From an Unmanned Aerial Vehicle journal March 2009
Integrating Solar Induced Fluorescence and the Photochemical Reflectance Index for Estimating Gross Primary Production in a Cornfield journal December 2013
A Field Platform for Continuous Measurement of Canopy Fluorescence journal September 2010
The role of xanthophyll cycle carotenoids in the protection of photosynthesis journal January 1996
Effect of leaf age and position on net photosynthetic rates in maize (Zea Mays L.) journal May 1986
Solutions for a cultivated planet journal October 2011
A narrow-waveband spectral index that tracks diurnal changes in photosynthetic efficiency journal July 1992
The photochemical reflectance index: an optical indicator of photosynthetic radiation use efficiency across species, functional types, and nutrient levels journal November 1997
Lever-arm and boresight correction, and field of view determination of a spectroradiometer mounted on an unmanned aircraft system journal September 2019
Error Budget for Geolocation of Spectroradiometer Point Observations from an Unmanned Aircraft System journal October 2018
Wide Dynamic Range Vegetation Index for Remote Quantification of Biophysical Characteristics of Vegetation journal January 2004
Relationship Between Remotely-sensed Vegetation Indices, Canopy Attributes and Plant Physiological Processes: What Vegetation Indices Can and Cannot Tell Us About the Landscape journal March 2008
Food Security: The Challenge of Feeding 9 Billion People journal January 2010
PhotoSpec: A new instrument to measure spatially distributed red and far-red Solar-Induced Chlorophyll Fluorescence journal October 2018
Sun‐induced Chl fluorescence and its importance for biophysical modeling of photosynthesis based on light reactions journal April 2019
Advancing Terrestrial Ecosystem Science With a Novel Automated Measurement System for Sun‐Induced Chlorophyll Fluorescence for Integration With Eddy Covariance Flux Networks journal January 2019
Improving the monitoring of crop productivity using spaceborne solar-induced fluorescence journal November 2015
Developments for vegetation fluorescence retrieval from spaceborne high-resolution spectrometry in the O 2 -A and O 2 -B absorption bands journal January 2010
Retrieval and global assessment of terrestrial chlorophyll fluorescence from GOSAT space measurements journal June 2012
Using field spectroscopy to assess the potential of statistical approaches for the retrieval of sun-induced chlorophyll fluorescence from ground and space journal June 2013
Global and time-resolved monitoring of crop photosynthesis with chlorophyll fluorescence journal March 2014
Some characteristics of reduced leaf photosynthesis at midday in maize growing in the field journal June 1999
High Throughput Field Phenotyping of Wheat Plant Height and Growth Rate in Field Plot Trials Using UAV Based Remote Sensing journal December 2016
Optical and mechanical performance of a novel magnetically actuated MEMS-based optical switch journal April 2005
Acquisition of NIR-Green-Blue Digital Photographs from Unmanned Aircraft for Crop Monitoring journal January 2010
Interpreting vegetation indices journal December 1991
Non-destructive estimation of foliar chlorophyll and carotenoid contents: Focus on informative spectral bands journal June 2015
Informative spectral bands for remote green LAI estimation in C3 and C4 crops journal March 2016
Will photosynthesis of maize ( Zea mays ) in the US Corn Belt increase in future [CO 2 ] rich atmospheres? An analysis of diurnal courses of CO 2 uptake under free-air concentration enrichment (FACE) journal June 2004
Directly estimating diurnal changes in GPP for C3 and C4 crops using far-red sun-induced chlorophyll fluorescence journal January 2017
Measurement and Analysis of Bidirectional SIF Emissions in Wheat Canopies journal May 2016
Atmospheric Correction for Tower-Based Solar-Induced Chlorophyll Fluorescence Observations at O2-A Band journal February 2019
Influence of the canopy BRDF characteristics and illumination conditions on the retrieval of solar-induced chlorophyll fluorescence journal December 2017
Application of neural networks to discriminate fungal infection levels in rice panicles using hyperspectral reflectance and principal components analysis journal July 2010
Climate Trends and Global Crop Production Since 1980 journal May 2011
Perspectives for Remote Sensing with Unmanned Aerial Vehicles in Precision Agriculture journal February 2019
Intercomparison of UAV, Aircraft and Satellite Remote Sensing Platforms for Precision Viticulture journal March 2015
High-throughput field phenotyping using hyperspectral reflectance and partial least squares regression (PLSR) reveals genetic modifications to photosynthetic capacity journal September 2019
Performance of Spectral Fitting Methods for vegetation fluorescence quantification journal February 2010
Leaf level detection of solar induced chlorophyll fluorescence by means of a subnanometer resolution spectroradiometer journal August 2006
Remote sensing of solar-induced chlorophyll fluorescence: Review of methods and applications journal October 2009
Sun-Induced Chlorophyll Fluorescence, Photosynthesis, and Light Use Efficiency of a Soybean Field from Seasonally Continuous Measurements journal February 2018
Remote sensing of solar-induced chlorophyll fluorescence (SIF) in vegetation: 50 years of progress journal September 2019
A vapor pressure deficit effect on crop canopy photosynthesis journal April 1990
The MK II Fraunhofer Line Discriminator (FLD-II) for Airborne and Orbital Remote Sensing of Solar-Stimulated Luminescence journal August 1975
Linking chlorophyll a fluorescence to photosynthesis for remote sensing applications: mechanisms and challenges journal May 2014
Detection of citrus canker using hyperspectral reflectance imaging with spectral information divergence journal July 2009
Obtaining the three-dimensional structure of tree orchards from remote 2D terrestrial LIDAR scanning journal September 2009
Compensation of Oxygen Transmittance Effects for Proximal Sensing Retrieval of Canopy–Leaving Sun–Induced Chlorophyll Fluorescence journal September 2018
Improved Bend Loss Formula Verified for Optical Fiber by Simulation and Experiment journal October 2007
Spectroscopic determination of leaf morphological and biochemical traits for northern temperate and boreal tree species journal October 2014
Direct Estimation of Aboveground Forest Productivity Through Hyperspectral Remote Sensing of Canopy Nitrogen journal October 2002
Maize canopies under two soil water regimes. journal February 1998
Canopy Structure, Light Interception, and Photosynthesis in Maize journal November 2003
Drought onset mechanisms revealed by satellite solar-induced chlorophyll fluorescence: Insights from two contrasting extreme events: FLUORESCENCE AND DYNAMIC DROUGHT MONITOR journal November 2015
Red and photographic infrared linear combinations for monitoring vegetation journal May 1979
Bidirectional sun-induced chlorophyll fluorescence emission is influenced by leaf structure and light scattering properties — A bottom-up approach journal March 2015
Unmanned Aerial Systems (UAS)-Based Methods for Solar Induced Chlorophyll Fluorescence (SIF) Retrieval with Non-Imaging Spectrometers: State of the Art journal May 2020
Phenology Dynamics of Dryland Ecosystems Along the North Australian Tropical Transect Revealed by Satellite Solar‐Induced Chlorophyll Fluorescence journal May 2019
Linking canopy scattering of far-red sun-induced chlorophyll fluorescence with reflectance journal May 2018
FluoSpec 2—An Automated Field Spectroscopy System to Monitor Canopy Solar-Induced Fluorescence journal June 2018
High-Throughput Phenotyping of Maize Leaf Physiological and Biochemical Traits Using Hyperspectral Reflectance journal November 2016
Fluorescence, temperature and narrow-band indices acquired from a UAV platform for water stress detection using a micro-hyperspectral imager and a thermal camera journal February 2012
Seasonal stability of chlorophyll fluorescence quantified from airborne hyperspectral imagery as an indicator of net photosynthesis in the context of precision agriculture journal June 2016
A PRI-based water stress index combining structural and chlorophyll effects: Assessment using diurnal narrow-band airborne imagery and the CWSI thermal index journal November 2013
The application of small unmanned aerial systems for precision agriculture: a review journal July 2012
Comparison of Bi-Hemispherical and Hemispherical-Conical Configurations for In Situ Measurements of Solar-Induced Chlorophyll Fluorescence journal November 2019
Managing nitrogen for sustainable development journal November 2015
Model-based analysis of the relationship between sun-induced chlorophyll fluorescence and gross primary production for remote sensing applications journal December 2016
On the relationship between sub-daily instantaneous and daily total gross primary production: Implications for interpreting satellite-based SIF retrievals journal February 2018