Input and Migration of Dissolved Organic Carbon in Soils of Forest Ecosystems in the Subzone of Deciduous—Coniferous Forests

摘要

The results of four-year monitoring of natural waters in forest ecosystems of the Zvenigorod Biological Station (Moscow State University, Moscow oblast) show regular changes in the concentrations and fluxes of dissolved organic carbon (DOC) within theatmospheric precipitation—through/all—soil waters system. Precipitation passing through the tree canopy is enriched with DOC (2-3 and 9-24 mg/L). The average carbon concentration in soil waters reaches 100—110 mg/L in complex spruce and pine-spruce forests and does not exceed 40—60 mg/L in spruce—birch forests.The DOC concentration in natural waters is subject to high spatial and temporal variability expressed both in seasonal and long-term cycles. The lack of coordination between temporal peaks confirms that air-borne or canopy-derived DOC has little impact on DOC in soil waters. DOC leaching from the upper 40-cm soil layer during the growing period is higher than throughfall input. The highest DOC losses are observed in weakly derno—shallow podzolic soil in the complex spruce forest, which has the most coarse-grained texture.