Table 4: Descriptive statistics of the calibration and validation data sets for the prediction of clay and organic carbon content with laboratory and HyMap image spectra.

Calibration data sets Laboratory HyMap Number of samples Clay (g kg−1) Organic carbon (g kg−1) Mean SD Min Max Mean SD Min Max Lab_2004 HyMap_2004 20 108.07 48.38 48.03 186.64 9.60 3.17 5.25 19.59 Lab_2005 HyMap_2005 38 99.12 50.05 38.45 216.18 9.16 2.95 5.01 17.48 Lab_2008 HyMap_2008 11 97.31 45.68 52.22 197.20 6.66 1.47 4.31 10.34 Validation data sets Laboratory HyMap Number of samples Clay (g kg−1) Organic carbon (g kg−1) Mean SD Min Max Mean SD Min Max Lab_2004 — 115 130.22 67.45 36.53 329.47 10.42 4.02 4.31 24.79 Lab_2005a — 97 137.83 67.53 36.53 329.47 10.74 4.16 4.31 24.79 Lab_2005b HyMap_2005 29 92.06 52.36 36.53 237.52 8.89 3.73 5.55 24.79 Lab_2004 — 124 129.57 66.26 36.53 329.47 10.62 3.90 5.01 24.79