Monitoring of Cotton Canopy Chlorophyll Density and Leaf Nitrogen Accumulation Status by Using Hyperspectral Data Monitoring leaf nitrogen accumulation with hyper-spectral remote sensing in wheat QUANTITATIVE RELATIONSHIP BETWEEN LEAF NITROGEN ACCUMULATION AND CANOPY REFLECTANCE SPECTRA IN RICE AND WHEAT Estimation of winter wheat leaf nitrogen accumulation based on coupling ground- and space- remotely sensed information. Estimation of optimum normalized difference spectral index for nitrogen accumulation in wheat leaf based on reduced precise sampling method. Relationship of Leaf Nitrogen Status to Canopy Reflectance Spectra in Wheat Monitoring Leaf Nitrogen Accumulation with Canopy Spectral Reflectance in Rice