Research Article

Image Analysis to Estimate Mulch Residue in Soil

Table 3

Comparison of the soil area percentage values obtained by thresholding methods (Otsu (OT), Ridler-Calvard (RC), manual threshold (MT), and local entropy (LE)) with the reference area (). The comparison was analyzed with a paired 2-tailed Student’s -test and a paired 2-tailed Wilcoxon nonparametric test in case of LE.

GroupsAverageS.D. (Dif.) bilateral*
G1G2Dif.G1G2

−1.7340.6942.427.42−1.150.2637
−1.1740.6941.867.61−0.750.4611
−3.2240.6943.916.53−2.420.0241
−5.0540.6945.7319.230.0540

In bold the pair of methods that present significant differences in the areas at level . S.D. (Dif.): standard deviation of the mean difference.