Hyperspectral Reflectance Characteristics for corn canopy in different fertilization in irrigated area of Hexi corridor, Northwest China

摘要

Diagnosis of crop growth and nutrient status is critical for prediction of agriculture yield and quality at Growth stage. one experiments, in 2010 were conducted to find out corn canopy spectral characters in different fertilization non-destructively measurement and for assessing nutrition status non-destructively at Zhangye irrigated area of Hexi corridor northwest China. The results revealed that the spectral differences are clear for the canopy and leaves of corn under different fertilizer levels in near infrared region, and the canopy spectral reflectance are similar in the visible region. In the different growth stage, the hyperspectral reflectance of the canopy level are different, and that of the canopy is highest at heading stage and lowest at seven-leaf stage in near infrared region and in the shortwave and the spectral variation trend is reverse, meanwhile, that is highest at seven-leaf stage. And the reflectance in visible region is not notable in grown stage. Canopy spectral reflectance difference is obviously in infrared and the shortwave region; this indicates the possibility to identify the fertilizer type using the hyperspectral reflectance data.