210
mit:
together 535 kinds of objects (water bodies, rocks and minerals, vegetation, crops, and man
made objects) were measured and 15,026 spectral curves were obtained. Multi-temporal data were
gained in measuring crops like wheate, rice, corn, bean, cotton and millet. Most of the
measurements were done both on airborne and in the field.
2) . Spectral Database
As mentioned above, huge amount of spectral data had been obtained Therefore, the projects
were also contacted with a spectral database creation as to be a basis of SIS( Spectral
Information System). The database had been created and collected 5 main types, 535 kinds of
optical, microwave, and different temporal data of spectral characteristics with parameters
of environment and background. Not only the data stored and managed but also common statistics
software package was edited and rearranged in the database. Beside, this system had interface
with long distance communication network. Now, this database is well prepared to provide with
renew, standard, continuous and some analyzing functions for various applications.
3) . Analysis of Spectral Features
As well known, the analysis of spectral features is a basic work in remote sensing application,
Some examples of analysis for vegetation and soil results are as follows:
a. Vegetation
In range 350nm to 2500nm, 10 wavelenth ranges were divided as to be the spectral feature
describtions. Each of them has its own characteristics and behaviours.
Main Spectral Features of Vegetation
(1) . 350nm-490nm
380nm weak absorption atmosphere
400-450nm strong absorption chlorophyll
425-490nm strong absorption carotene
(2) . 490nm-600nm
490-560nm sub-strong absorp. carotene
530-590nm main absorption red aquatic protein
550nm strong reflec. peak chlorophyll
(3) . 600nm-700nm
610-660nm main absorption blue aquatic protein
650-700nm 81rong absorption chlorophyll
(4) . 700nm-750nm At 700nm reflectance increasing sharply
and keep high in the rest part.
(5) . 750nm-1300nm A undulation waveform and higher reflec.
strong absorption water, Oxygen
weak absorption water
strong absorption
reflec. peak
( 6 ).
(7) .
( 8 ) .
(9).
760nm
850-910nm
960-1120nm
890nm
1080nm
1260nm
1300nm-1600nm
1360-147 Onm
1600nm-1830nm
1830nm-2080nm
2080nm-2350nm
(10). 2350nm-2500nm
b. Soils
Former studies in soil spectrum are concentrated on reflectance features in visible range and
the relationships between these features and biological and physical characteristics. Recent
study focus on high spectral resolution features of main clay minerals in soils at near
infrared region. The results show that there are four main clay minerals in soils, the
features as follows:
Kaolinite: Pband (2200nm) >0.5
Asy (2200nm) >1.0
Montmorillonite: Pband (19OOnm) =1.0
Asy (1900nm) <-1.0
The valley form and lower reflec.
strong absorption water, C02
A higher reflec. peak water content
A wide absorption water, C02
A medium reflec. peak water content
main absorption water,C02
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