Reflection of layered bean leaves over different soil backgrounds: measured and simulated spectra
作者:
J. R. MILLER,
M. D. STEVEN,
T. H. DEMETRIADES-SHAH,
期刊:
International Journal of Remote Sensing
(Taylor Available online 1992)
卷期:
Volume 13,
issue 17
页码: 3273-3286
ISSN:0143-1161
年代: 1992
DOI:10.1080/01431169208904118
出版商: Taylor & Francis Group
数据来源: Taylor
摘要:
A GER IRIS field spectrometer has been employed in a laboratory setting to measure the spectral reflectance of multiple layers (1, 2, 3, and 4) of French bean leaves overlayed on three soil backgrounds (peat, sand and loam), each in either a dry or wet (watered to field capacity) condition. Spectral reflectance data for the dry sand and dry peat backgrounds and for both sides of the single bean leaf, over these two backgrounds, were used with a simple model to derive the basic leaf optical properties: the diffuse transmittance and front and back reflectance spectra. These basic leaf optical spectra were then used to simulate the effect of leaf layering over the six background soils at 100 nm intervals between 450 nm and 2450 nm. Reflectance differences over the entire spectrum between the simulated and measured spectra were consistently less than 3 per cent for the six background soils used, with leaf to leaf variability thought to play the major role in the observed variability. These results suggest that representative leaf and soil background reflectance data collected with field-type spectrometers can be used to model spectral trends expected in typical field crops over a wide range of spectral backgrounds and percentage cover. For example, such data for a particular agricultural setting may be used to explore suitable spectral indicates to minimize the dependence of dcrived-LAI on soil background as well as obtain the leaf diffuse spectral reflectance and transmission functions for the crop of interest, which are the link to physical properties such as pigment concentration and leaf moisture content.
点击下载:
PDF (249KB)
返 回