Geoscience Reference
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Fig. 8.31 Spectral reflectance
of different objects. http://
commons.wikimedia.org/
wiki/File:Incoming_spectral_
reflectance_from_different_
objects_to_a_sensor_system.
svg
registered by many vegetation indices. All vegetation indices show a qualitative
relationship to variations in vegetation. However, there exist signi
cant differences
among the vegetation indices over desert, grassland, and forested biomes. For
example, NDVI is sensitive to and responded primarily to the highly absorbing red
re
ectance band, while other indices such as SARVI are more responsive to vari-
ations in the near-infrared band. It is evident that different indices have their own
advantages in retrieving vegetation information. It is very dif
fl
cult to precisely
attribute any vegetation index to any particular vegetation biophysical or mor-
phological parameter. Therefore, creation of universal algorithm for the classifi-
cation of vegetation characteristics is possible by using the model represented in
Fig. 1.19 that realizes the GIMS technology. In this case, the vector
ʨ
={y i , i =1,
, m} is synthesized, where yi i is separate vegetation index from Table 8.17 and
m
gives a
possibility to form cluster space that allows the recognition of different states of
vegetation covers.
25 is the number of indices included to the vector
ʨ
. Vector
ʨ
 
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