The spectral reflectance of young rice plants was measured in the visible and near-IR region of the spectrum using a commercially available fiber optic contact probe and miniature spectrometer. This work aims to identify an empirical spectral index which changes when rice is exposed to increased levels of chloride anions in the irrigation water and soil. The ratio of near IR reflectance to that of green, R750/555 is known to be a quantitative measure of chlorophyll content in the leaf but int his study does not show a consistent shift for sample which are exposed to chloride levels equal to or less than 0.1 percent by mass of soil. However, leaf contact spectral reflectance measurements did reveal a significant and consistent increase in R750/555 along the length of the leaves, and this variation should represent an important factor in modeling remote and proximal sensing data.
[1]
K. Inada,et al.
Spectral Ratio of Reflectance for Estimating Chlorophyll Content of Leaf
,
1985
.
[2]
S. Gerstl,et al.
Coupled atmosphere/canopy model for remote sensing of plant reflectance features.
,
1985,
Applied optics.
[3]
H. Nilsson.
Remote sensing and image analysis in plant pathology.
,
1995,
Annual review of phytopathology.
[4]
A. Springsteen,et al.
6 - Reflectance Spectroscopy: An Overview of Classification and Techniques
,
1998
.
[5]
Gregory A. Carter,et al.
Responses of leaf spectral reflectance to plant stress.
,
1993
.