MORPHOLOGICAL STRUCTURE AND BIOCHEMICAL POTENTIAL OF PYROGENIC SOILS OF THE PINE FORESTS OF THE ALTAI REGION’S OB RIVER AREA
The paper describes the features of the morphological structure and biochemical potential of the pyrogenic sod-shallow podzolic soils of the intermountain depressions and pyrogenic soils with the buried second humus horizon on the watersheds of the Priobskiy (the ob river area) pine forest of the Altai Region, common for the burnt site of the surface fire of 2004. It has been found that the soil morphological structure of relief depressions slightly changes with the successional changes in the ground cover of the burnt site; a characteristic feature is the presence of charcoal inclusions in the humus-accumulative horizon. These soils reveal increased activity of catalase and urease as compared to the background sod-shallow podzolic soil common for the climax pine forest. The ratio of polyphenoloxidase activity to peroxidase corresponds to the background soils. In the watersheds, there is little development of ground vegetation and the intensification of deflation processes. The soil with the buried second humus horizon which has a reduced biochemical potential in comparison with the background soils was opened. Increased activity of polyphenoloxidase leads to an increase in the ratio of polyphenoloxidase to peroxidase as compared to the ratio in the humus-accumulative horizon of background soils. This change in enzyme activity reduces the intensity of humus oxidation and causes the safety and stability of the second humus horizon in the soil.