To improve accuracy of the prediction of soil carbon using a soil carbon calibration model,feature transformation and feature selection was done to soil infrared reflected spectral( NIRS) data obtained with a field ambulatory infrared spectroscopy device in situ. Firstly,feature transformation was done of the soil NIRS data through independent component analysis( ICA),principle component analysis( PCA) or wavelet analysis( WA),and then feature selection was through uninformative variable elimination( UVE),s...