| 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, its spectral resolution is commonly less than 10nm and less than 20-40nm of diagnosis wide wave of land. It has several hundreds and thousands wave bands and first-order and second derivative spectra 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; Because of the special characteristic of hyperspectra, especially identification and classification of land surface and extracting useful information and so on. This technique has tremendous applied foreground. The study on cultivating physiological characteristics and yield of crop is the most prime and core part of hyperspectra. The main objectives of the study includes:1) To find out some spectral wave bands and vegetation indices which would be applicable to estimate cultivating physiological characteristics and yield of cotton;2) The hyperspectral remote sensing models of different cultivating physiological characteristics and yield are built in different growth stages, which are based on the hyperspectral reflectance characteristic parameters.The main contents of the study are as following:1) This study is based on the rank difference of the nitrogenous nutrition level and watering level and density by man-made style through three years cotton farm experiment.2) Canopy spectral of cotton is measured by Analytical Spectral Devices (FieldSpec) in different growth stage. The study has analyzed the variation of cotton canopy reflectance with wavelength, compared the canopy reflectance curves of different nitrogenous nutrition level and watering level, also compared reflectance curves of leaf and cotton canopy. The study has also analyzed the variation of the spectral "red edge" features and meantime designed 46 hyperspectral reflectance characteristic parameters to build the hyperspectralremote sensing models of different cultivating physiological characteristics and yield in different growth stages.3) According to the statistical correlation coefficients between spectral reflectance in 350-2500nm range and cultivating physiological characteristics and yield are analyzed in all growth stages, all the sensitive bands for different cultivating physiological characteristics and yield are found.4) The hyperspectral remote sensing models of different cultivating physiological characteristics and yield are built in different growth stages, which are based on the 46 hyperspectral reflectance characteristic parameters.The research achievements are as following:1) The spectral "red edge" features are calculated and analyzed. Red-shift is found with early increase in cotton's budding stage; Blue-shift is found with late decrease in cotton's lint-opened stage. The red edge absorption width decreases in the early growth stages, and increases in the late growth stages.2) The statistical correlation coefficients between spectral reflectance in 350nm-2500nm range and cultivating physiological characteristics and yield are analyzed in all growth stages, so all the sensitive bands for different cultivating physiological characteristics and yield are found. The statistical correlation coefficients between LAI plant water content and spectral reflectance in near-infrared bands at 770-850nm 770-950nm, 1000-1300nm are significant in all growth stages.3) The statistical correlation coefficients between 46 hyperspectral reflectance characteristic parameters and cultivating physiological characteristics and yield are analyzed in all growth stages, the hyperspectral remote sensing models of different cultivating physiolog...
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