Первичное почвообразование на субстратах разного гранулометрического состава в посттехногенных экосистемах таёжной зоны

Abstract

The paper focuses on the primary soil formation under automorphic conditions in the middle taiga sub-zone of the European North-East of Russia (Komi Republic) on the post-technogenic territories (quarries for the extraction of minerals (construction sand)) with different soil materials (ancient alluvial sands; fluvioglacial sands and sandy loams, moraine loams). In the quarries, the processes of soil formation and vegetation cover development are interdependent and are affected by the properties of soil-forming rocks. Along with the improvement of soil properties (from sandy loam to loam), the biometric parameters of pine stands increase; in the ground cover, dominating lichens are replaced by mosses, and then by grasses. The biogenic accumulation rates of organic matter increase along with the transition of soil material to fine-textured. In automorphic conditions, the accumulation rate of Corg. in soil of sandy quarry under sparse young lichen pine forest reaches 0.1, in sandy loam under young forb-moss pine forest – 0.3, in loam under young grass-forb pine forest – 0.6 t/ha/year. Already in the first succession decades, every study soil demonstrates weakly expressed processes of eluviation and illuviation (the beginning of podzolization). These processes are evidenced by morphological signs (the appearance of bleached quartz grains and whitish patches under organic horizon and in its lower part), redistribution of silicon, iron, and aluminum compounds, as well as of silty particles proportion.