Sun-angle and canopy-architecture effects on the spectral reflectance of six wheat cultivars

Autor: Harold W. Gausman, C. Elaine Ezra, Paul J. Pinter, Ray D. Jackson
Rok vydání: 1985
Předmět:
Zdroj: International Journal of Remote Sensing. 6:1813-1825
ISSN: 1366-5901
0143-1161
DOI: 10.1080/01431168508948330
Popis: Canopy spectral reflectances were measured over six cultivars of spring wheat (Trticum aestivum L.) grown at Phoenix, Arizona. Data were collected at 30-45 min intervals on 9 March 1983 using two ground-based radiometers with bandpass characteristics similar to those of the Muttispectral Scanner and Thematic Mapper on LANDSAT-4 and -5. Major differences in reflectance were observed among cultivars at every time period despite their apparent similarities in green leaf area and green biomass. Single-leaf spectra measured in the laboratory with a spectrophotometer revealed no cultivar-related differences and supported the contention that the reflectances were strongly influenced by canopy architectural features. The diurnal patterns of reflectance reinforced this conclusion with planophile canopies exhibiting the least amount of variability due to changes in Sun angle and erectophile canopies showing the most. These data underscore the complexities of interpreting remotely sensed multispectral data ...
Databáze: OpenAIRE