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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Lawn_Grass GDS91 Shifts DESCRIPT

DOCUMENTATION_FORMAT: PLANT

SAMPLE_ID: GDS91

PLANT_TYPE: Grass

PLANT: Grass

LATIN_NAME: Not Available

COLLECTION_LATITUDE: Not Available # degrees and decimal minutes (N or S)

COLLECTION_LONGITUDE: Not Available # degrees and decimal minutes (W or E)

DATUM: Not Available # coordinate datum

COLLECTION_LOCALITY: Denver West Building #2, Golden, Colorado

ORIGINAL_DONOR: Gregg Swayze

SAMPLE_DESCRIPTION:

The original sample was measured, and a series of shifted and ratioed spectra computed for spectrally testing chlorophylll absorption band shifts. This grass, probably Kentucky Bluegrass was from the lawn outside our offices at the time the grass was picked on June 18, 1991. Generic lawn grass. Run immediately after picking. See Lawn Grass GDS91 description.

The series of shifted spectra are described in the spectroscopic description, below.

END_SAMPLE_DESCRIPTION.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: Water: %(of fresh weight)
COMPOSITION: Total_Chlorophyll: %(of fresh weight)
COMPOSITION: Chlorophyll_A: %(of fresh weight)
COMPOSITION: Chlorophyll_B: %(of fresh weight)
COMPOSITION: Nitrogen: %(of dry weight)
COMPOSITION: Lignin: %(of dry weight)
COMPOSITION: Cellulose: %(of dry weight)

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

TRACE_ELEMENT_ANALYSIS:

TRACE_ELEMENT_DISCUSSION:

END_TRACE_ELEMENT_DISCUSSION.

SPECTROSCOPIC_DISCUSSION:

A series of 5 computed spectra were made

Lawn_Grass GDS91 shifted 3nm W1R1Ba AREF

The spectrum above is a 3 nanometer (0.003 micron) shift to longer wavelengths of the original GDS91 spectrum.

Lawn_Grass GDS91 /shifted 3nm W1R1Ba AREF

The spectrum above is the unshifted / shifted spectrum. The ratio of these two spectra produces a hump with a maximum near 0.69 microns. This ratio method is documented in Figure 26 of
Clark, R. N., Chapter 1: Spectroscopy of Rocks and Minerals, and Principles of Spectroscopy, in Manual of Remote Sensing, Volume 3, Remote Sensing for the Earth Sciences, (A.N. Rencz, ed.) John Wiley and Sons, New York, p 3- 58, 1999, and can be found online at: http://speclab.cr.usgs.gov/PAPERS.refl-mrs

Lawn_Grass GDS91 +const 1.0 W1R1Ba AREF

The spectrum above is the original Lawn_Grass GDS91 spectrum plus a constant of 1.0. This spectrum represents a weakened chlorophyll feature when partial vegetation covers the area of a remote sensing pixel.

Lawn_Grass GDS91 +1shft 3nm W1R1Ba AREF

The spectrum above is original Lawn_Grass GDS91 spectrum plus a constant of 1.0 and shifted to longer wavelengths by 3 nanometer (0.003 micron).

Lawn_Grass GDS91 +1shf/unshifted W1R1Ba AREF

The spectrum above is the Lawn_Grass GDS91 plus constant 1.0 ratioed to the shifted spectrum (also with the constant 1.0). The ratio of these two spectra produces a hump with a maximum near 0.73 microns showing what might be expected to detect red-edge shifts in areas of trace vegetation. This ratio method is documented in Figure 26 of
Clark, R. N., Chapter 1: Spectroscopy of Rocks and Minerals, and Principles of Spectroscopy, in Manual of Remote Sensing, Volume 3, Remote Sensing for the Earth Sciences, (A.N. Rencz, ed.) John Wiley and Sons, New York, p 3- 58, 1999, and can be found online at: http://speclab.cr.usgs.gov/PAPERS.refl-mrs

The ratio method for detecting red-edge shifts is used in the Tetracorder mapping system:
Clark, R.N., G. A. Swayze, K. E. Livo, R. F. Kokaly, S. J. Sutley, J. B. Dalton, R. R.McDougal, and C. A. Gent., Imaging Spectroscopy: Earth and Planetary Remote Sensing with the USGS Tetracorder and Expert Systems, Journal of Geophysical Research, In Press, 2003. http://speclab.cr.usgs.gov/PAPERS/tetracorder

Very strong chlorophyll absorption in the visible and strong liquid water absorptions near 1, 1.2, 1.5 and 2 microns.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib04a r 5286 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 12140 0.2-3.0µm 200
LIB_SPECTRA: splib05a r 12157 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 12172 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 12188 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 12206 0.2-3.0µm 200 g.s.=


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