Hyperspectral Remote Sensing Estimation Models Of Biophysical And Biochemical Parameters Studied

Multispectral remote sensing notes land spectra by non- continual wide wave band fashion in wave width region, which use one data of wide wave band represents radiation trend of a relative wide spectral region. By Comparison with multispectral remote sensing, hyperspectra can completely note everything by a integrated spectral curve in its watching region and can receive continual spectral information. It has several hundreds and thousands wave bands and the first-order and the second derivative spectra and logarithm transform and every vegetation indices and so on. This is not increase in data number but is increase in information. The information capacity is add to several tenfold or hundreds; secondly, Its spectral resolution is commonly less than 1 Onm and less than 20-4Onm of diagnosis wide wave of land. Because of the special characteristic of hyperspectra, especially identification and classification of land surface and extracting useful information and so on, it has superiority to other techniques. This technique exhibits to tremendous applications foreground. The study on bio-physical and bio-chemical characteristics of plant is the most prime and core part of hyperspectra. This study is one part of the project supported by foundation of national science and nature-- Study on the mechanism of variation of rice spectral characteristics caused by nitrogen level. 156 The main objectives of the study: The main objectives of the study includes: Oto find out some spectral wave bands and vegetation indices which would be applicable to estimate bio-physical and bio-chemical parameters of rice @I~to evaluate the potential of measured multispectra and hyperspectra to estimate bio-physical and bio-chemical parameters of Rice. The main contents of the study are as following: 1) This study is base on the rank difference of the nitrogenous nutrition level by the man-made style through two years rice farm experiment about the difference of the nitrogenous nutrition level 2) Canopy spectral of different nitrogen application is measured by Analytical Spectral Devices (FieldSpec? in different stage. The study has analyzed the variation of rice canopy reflectance with wavelength and time, compared the reflectance curves of water surface, wet land, strawy land and rice canopy. After The influence on rice canopy reflectance spectra by spectral resolution is analyzed, the spectral resolution has been definituded that is in 3~24nrn which can reflected the reflectance characteristics of green plants. When spectral resolution is larger 24nm, some hyperspectra reflectance characteristics disappears in 930?054 nm. The optimum spectral bandwidth for smoothing is smaller than lOnm. The study is analyzed the elimination of background signals (such as wet soil , water and so on) using derivative canopy spectra of rice under different nitrogen status. 3) According to satellite sensors channels spectra which we have had and spectral regions which have physical content, 27 variables of multiple spectra and 12 vegetation indices in 157 common use and 19 variables of hyperspectra which is base on spectral position, spectral area and vegetation indices can be constr...