THE TRANSFORMATION OF ORGANIC MATTER AND CARBON DYNAMICS IN THE MIRES OF THE NORTHERN PART OF THE MIDDLE-RUSSIAN UPLAND

The article discusses the results of an experiment on the transformation of different plant remains in the ecological conditions of floodplain and watershed mires which are located in the north of the Middle-Russian Upland. The objects of the study were Menyanthes trifoliata, Filipedula ulmaria, Equisetum fluviatile, Carex acutiformis and Sphagnum fallax. It is shown that the intensity of decomposition of plant residues depends on their chemical composition (ash content, C/N ratio) and biotope conditions (aeration, mineralization of mire waters). During the 12 months of the experiment, the highest values of mass loss were noted for Menyanthes trifoliata and Filipendula ulmaria, the minimum – in sphagnum moss. In the process of decomposition of plant residues, the carbon content is changing. At the same time, in a floodplain mire which is characterize by a seasonally variable hydrological regime and rich water and mineral nutrition, a decrease of carbon content was noted in plant residues. In the watershed mire, under conditions of stable moisture and poor mineral nutrition, the carbon content increases during the experiment. Carbon stocks in plant samples decreased during the experiment. However, the highest values of carbon reserves were preserved in plant samples at the watershed mire, which is correlates with carbon concentration in peat and their active vertical growth. The conducted experiment makes it possible to assess the contribution of different mire types to carbon deposition.