THE SPECTRAL REFLECTANCE OF AMERICAN SOILS
SPECTRAL REFLECTANCES EXTENDING FROM 320 TO 1,000 MANOMETERS HAVE BEEN OBTAINED FOR 160 SOIL SAMPLES COLLECTED FROM 36 STATES. MEASUREMENTS WERE MADE OF BOTH WET AND DRY SAMPLES, WHICH VARY WIDELY IN COLOR AND REFLECTANCE. AN EXAMINATION OF THE 160 SETS OF CURVES INDICATES THAT THEY CAN BE CLASSIFIED INTO THREE GENERAL TYPES WITH RESPECT TO THEIR CURVE SHAPE. A CHARACTERISTIC VECTOR ANALYSIS WAS MADE OF THE SPECTRAL REFLECTANCE DATA; IT SHOWED THAT BY LINEAR COMBINATIONS OF FOUR VECTORS AND THE MEAN CURVE, EACH SET OF DATA COULD BE RECONSTITUTED TO A HIGH DEGREE OF ACCURACY. THEORETICALLY THEN, THE REFLECTANCE DATA FOR ALL WAVELENGTHS SHOULD BE PREDICTABLE FROM MEASUREMENTS MADE AT AS FEW AS FOUR WAVELENGTHS. EMPIRICAL REGRESSION EQUATIONS HAVE BEEN DERIVED WHICH RELATE SPECTRAL REFLECTANCE DATA AT 35 WAVELENGTHS SPACED AT 20-NANOMETER INCREMENTS TO MEASUREMENTS MADE AT ONLY FIVE SPECIALLY SELECTED WAVELENGTHS. TO THE EXTENT THAT SOILS MAY BE IDENTIFIED BY THEIR REFLECTANCE CHARACTERISTICS, THIS ABRIDGED TECHNIQUE SEEMS TO HAVE SUFFICIENT ACCURACY FOR THE 160 SAMPLES WHICH HAVE BEEN MEASURED. /AUTHOR/
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Supplemental Notes:
- Vol 36, No 9, PP 955-966, 37 FIG, 3 TAB, 1 REF
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Authors:
- Condit, H R
- Publication Date: 1970-9
Media Info
- Serial:
Subject/Index Terms
- TRT Terms: Aerial photography; Calcites; Reflectivity; Sand; Soils; Spectroscopy
- Uncontrolled Terms: Chernozem soils; Reflectance
- Old TRIS Terms: Calcite sands; Pedalfer silt; Red quartz; Spectrophotogrammetry
- Subject Areas: Design; Geotechnology; Highways;
Filing Info
- Accession Number: 00202873
- Record Type: Publication
- Files: TRIS
- Created Date: Dec 7 1970 12:00AM