RELATIONSHIP BETWEEN COLOR VALUE AND NITROGEN IN FOREST MINERAL SOILS

To assess the extent to which moist color value of forest mineral soil s supports their differentiation according to concentrations of minera lizable and total N, 239 samples of 0-30-cm mineral-soil layers were e xamined for the relationship between nitrogen measures and selected ca tegorical climatic and soil variables. The best regression models, usi ng soil color value (SCV), climate, soil moisture and soil texture as categorical variables, explained nearly 70% of the variation in both m ineralizable and total N, with climate accounting for most of the vari ation. The results provided support for the present usage of SCV in es timating mineralizable and total N in forest soils but suggested impro vements for the development of a more effective estimation procedure.