The associatin between nitrogen mineralization rate and selected chemical characteristics of trumao and no-trumao soils were studied. Trumao soils are derived from recent volcanic ash. Under the name of no-trumaos were grouped soils derived from ancient volcanic ash, granitic rocks and glacial-alluvial deposits.
Mineralization rate was estimated by determining the amount of N - (NO3 + NO2 + NH4) produced during incubation of soil samples at 30º C for 14 days. The association between N mineralization and total-N, C/N ratio, available P, log (extractable-al) and pH was studied using simple correlation and regression analysis. Each soil group was studied separatelly. Regression analysis was used to elucidate multicollinearity problems, say, when two or more variables associated with mineralization were correlated one with another.