Application of portable hyper-spectral camera in andisols soil nitrogen assessment

Soil nitrogen content has very important influence on soil parameters and crop productions, so the soil nitrogen monitoring and management are urgently required to satisfy the demand for precision agriculture. This research is aimed to develop the simple and low cost monitoring methods to determine the soil nitrogen pools using hyper spectral camera in Andisols soil. Partial least square regression (PLSR) with cross-validation was used to calibrate the spectral data. The research estimated the potential of soil nitrogen qualitative analysis using visible (VIS) spectrographs, near infrared (NIR) spectrographs and combination of these two spectrographs. Results showed that model assessment accuracy by V10 (360nm-1010nm) spectrograph is higher than by N17E (900nm-1700nm) spectrograph. In addition, combining these two spectrographs increased the model prediction accuracy. Evaluation index (EI) test was employed in this research, and the results showed that prediction is acceptable to use of practical to predict soil nitrogen content.