Proceedings Article | 8 August 2007
KEYWORDS: Reflectivity, Vegetation, Hyperspectral simulation, Near infrared, Absorption, Remote sensing, Data modeling, Radiative transfer, Satellites, Computer simulations
The sensitivity of hyperspectral indices to LAI, chlorophyll contents and leaf internal structure at canopy level are
investigated using simulated canopy reflectance dataset, this method can avoid expensive and impractical surface
reflectance measurement, providing a theoretical basis for satellite-borne remote sensing. The model employed is
PROSAIL that couples leaf reflectance model PROSPECT and canopy radiative transfer model SAIL. Hyperspectral
indices used are NDVI, EVI, GI, RI, TVI, SIPI, PRI, TCARI, OSAVI, TCARI/ OSAVI, mNDVI705 and NDWI. Using
PROSAIL model, leaf and canopy reflectance under different chlorophyll contents, leaf internal structures, LAI and
water contents are first simulated and compared. Then using PROSAIL simulated canopy reflectance data, different
hyperspectral indices are calculated, the sensitivity of vegetation indices to LAI and chlorophyll contents is analyzed in
detail. And the sensitivity of vegetation indices to leaf internal structure is also analyzed. Results show that relationships
between hyperspectral indices and LAI are approximately logarithmic while the relationship between hyperspectral
indices and leaf internal structure is linear. EVI and TVI are good indicators to estimate LAI. GI, RI, TCARI, MNDVI705
can be used to estimate chlorophyll content. N has great influence on hyperspectral indices.
