Use of Airborne Hyperspectral Imagery to Map Soil Properties in Tilled Agricultural Fields

Table 5

Correlation between predicted analyte concentrations and topographic indices including (a) relative elevation data derived from 3 m LIDAR DEM, and (b) wetness index calculated from 3 m LIDAR DEM, for one of the six sampled fields (Mason). Predicted values were calculated for unsmoothed imagery (2.5 m pixel size) and for smoothed imagery to which a 3×3 low band filter had been applied. See Section 2 for analyte descriptions.

	C	Silt	Al	Fe
	𝑅^2	𝑅^2	𝑅^2	𝑅^2
(a) correlation with normalized elevation
unsmoothed	0.100	0.000	0.232	0.013
smoothed	0.051	0.007	0.386	0.000
(b) correlation with wetness index
unsmoothed	0.183	0.008	0.161	0.091
smoothed	0.178	0.021	0.317	0.037