Date post: | 01-Jan-2016 |
Category: |
Documents |
Upload: | oswin-hill |
View: | 222 times |
Download: | 0 times |
Remote Sensing to Estimate Chlorophyll Concentration Using Multi-Spectral Plant
Reflectance
P. R. Weckler Asst. Professor M. L. Stone Regents ProfessorN. Maness Professor R. Jayasekara Research EngineerC. Jones Research Engineer
Objective
• Estimate Chlorophyll concentration using chlorophyll content and biomass
BiomassionConcentratlChlorophylYieldlChlorophyl *
Sensors• Passive Sensor
- OSU Plant Reflectance sensor
• Active Sensor- Patchen Weedseeker™ PHD 600 Sensor
- Ntech Greenseeker™ Sensor
• Multi-Spectral Camera
Sensing Equipment
Spring, 1999 and 2000 Fall, 2000 and Spring, 2001
Fall, 2002
OSU Reflectance Sensor
OSU Reflectance Sensor
Patchen Weedseeker™ PHD 600 Sensor
OSU Reflectance Sensor
Ntech Greenseeker™
Sensor No camera used Olympus D-360L digital
camera DuncanTech MS3100 multispectral camera
Sensors
Experimental Plots
Vegetation Through Multi-spectral Camera
Spinach Plot with Reflectance Targets
Results
Chlorophyll Content vs. NDVIFall, 2002
y = 0.4738e4.1817x
r2 = 0.9187
0
5
10
15
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
NDVI
Chl
. Con
t, kg
/ha
Biomass vs. NDVIFall, 2002
y = 462.52e4.4826x
R2 = 0.9395
0.0
5000.0
10000.0
15000.0
20000.0
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
NDVI
Bio
mas
s, k
g/ha
ResultsNDVI/%VC vs. Chlorophyll Concentration
Fall, 2002
r2 = 0.0263
0.002
0.004
0.006
0.008
0.01
0.012
0.014
0.016
0.018
700 750 800 850 900 950
Chlorophyll Concentration, mg/kg
ND
VI/%
VC
NDVI/%VC vs. Chlorophyll Concentration Fall, 2002
r2 = 0.9508Week 4
r2 = 0.6762Week 5
r2 = 0.5473Week 6
r2 = 0.9845Week 7
r2 = 0.6629Week 8
0.002
0.004
0.006
0.008
0.01
0.012
0.014
0.016
0.018
700 750 800 850 900 950
Chlorophyll Concentration, mg/kg
ND
VI/%
VC
ResultsStudy NDVI vs
BiomssNDVI vs.
Chlorophyll
Yield
%Vegatative Coverage vs.
Biomass
NDVI/%VC vs. Chlorophyll
Concentration
Spring,1999 0.80 0.80 No camera data
-----------
Spring, 2000 0.81 0.77 No camera data
-----------
Fall, 2000 0.93 0.73 0.73 0.02
Spring, 2001 0.93 0.87 0.98 0.38
Fall, 2002 0.94 0.92 0.85 0.03
Conclusions• The NDVI readings gathered by the handheld sensors and the
multispectral camera were sensitive to changes in plant biomass and plant chlorophyll content in spinach .
• This study reaffirmed the correlation between %VC and dry biomass found by Lukina et al. (1999, 2000) and Ter-Mikaelian and Parker (2000).
• High correlation was observed between the %VC of the spinach as measured with digital imagery and the spinach biomass as measured in the laboratory (r2 = 0.73 to 0.98).
Conclusions
• The findings of Lukina et al. (1999, 2000) and Sembiring (1998) were also supported regarding NDVI readings producing a stronger estimate of chlorophyll content then of chlorophyll concentration.
• NDVI derived from processing images from a multispectral camera correlated well with handheld sensor NDVI.
• The multispectral camera provided accurate %VC information that correlated well with biomass results.
Further Studies
• Low correlations when predicting chlorophyll concentration from estimates of biomass and NDVI may suggest further investigation in following areas:
- canopy stacking
- background interference with sensors
QUESTIONS?
AcknowledgmentsDr. Jerry Brusewitz
Ted KerstenD. Chrz
Bruce BostianOklahoma Vegetable Research
Station,Bixby,Oklahoma