Numerical Classification of Some Indian Soils

A technique of numerical classification was applied to 13 soil series belonging to 5 great soil groups from Bellary, Bijapur and Dharwar districts of Karnataka and the Union Territory of Goa. Data on 32 soil characteristics were collected. The qualitative characteristics were first numerically coded and then all the characteristics were converted to a uniform scale by taking lowest as 0 or 1 and the highest as 100, adjusting the intermediates proportionately. Taxonomic similarities between different soil series were calculated by computing coefficients of resemblance such as similarity indices, correlation coefficients and Fisher's Z-values for all possible combinations (^l3C₂=78) of 13 soil series. Cluster analysis was later employed for grouping of theses oils into lesser number of groups.

The results, though broadly confirmed the earlier groupings of these soils, brought to light the extent of dissimilarities within the groups. This technique enabled to measure the affinity among different soils in quantitative terms and to examine the stages at which soils joined together to form major groups and thus to reduce their number (groups) at desired level of similarity.