Abstract

Assessment of the Nitrogen Status of Grasslands Using Continuum Removal.
Track: Agriculture
Authors: Tekeste Tewoldebrhan

The objective of this study was to classify grassland species based on palatability index of species and to investigate the potential of continuum removal analysis using field spectrometer and hyperspectral based remote sensing data for estimating grass nitrogen concentration in mixed grassland vegetations. The grassland area was classified into three paddocks based on different management practice; extensive grazing (paddock one and three), mowing and organic fertilization (paddock two). Canopy spectral measurements were collected for forty plots in the three paddocks using field radiometry and the airborne HyMap sensor in the range of 400-2500 nm. The results show that the nitrogen concentration was negatively correlated with palatability of overall species. Strong correlation was obtained in wavelengths where more nitrogen absorption features were present between band depth and band depth area. Continuum removed analysis was an effective method for estimating nitrogen concentration and applicable on HyMap and field spectroscopy data.