Abstract. Peatlands, storing significant amounts of carbon, are extremely vulnerable to climate change. The effects of climate change are projected to lead to a vegetation shift from Sphagnum mosses to sedges and shrubs. Impacts on the present moss-dominated peat remain largely unknown. In this study, we used a multiproxy approach to investigate the influence of contrasting vascular plant types (sedges, shrubs) on peat chemistry and decomposition. Peat cores of 20 cm depth and plant material (Sphagnum spp., Calluna vulgaris and Eriophorum vaginatum) from two ombrotrophic peatlands in the Italian Alps with a mean annual temperature difference of 1.4 ∘C were analyzed. Peat cores were taken under adjacent shrub and sedge plants growing at the same height above the water table. We used carbon, nitrogen and their stable isotopes to assess general patterns in the degree of decomposition across sampling locations and depths. In addition, analytical pyrolysis was applied to disentangle effects of vascular plants (sedge, shrub) on chemical properties and decomposition of the moss-dominated peat. Pyrolysis data confirmed that Sphagnum moss dominated the present peat irrespective of depth. Nevertheless, vascular plants contributed to peat properties as revealed by, e.g., pyrolysis products of lignin. The degree of peat decomposition increased with depth as shown by, e.g., decreasing amounts of the pyrolysis product of sphagnum acid and increasing δ13C with depth. Multiple parameters also revealed a higher degree of decomposition of Sphagnum-dominated peat collected under sedges than under shrubs, particularly at the high temperature site. Surprisingly, temperature effects on peat decomposition were less pronounced than those of sedges. Our results imply that vascular plants affect the decomposition of the existing peat formed by Sphagnum, particularly at elevated temperature. These results suggest that changes in plant functional types may have a stronger impact on the soil carbon feedback in a warmer world than hitherto assumed.

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Differential protection is more appropriate for multi-terminal lines than distance protection, due to its selectivity. However, the sampling process at all terminals should be synchronized. The new methods presented don't need the sampled values for comparison and therefore no synchronization.Firstly, the positive-sequence component of currents and voltages is calculated from the sampled values. Then, using line parameters, currents and voltages as well the admittances or apparent powers at the tap poin~are calculated for each line section. The sum of the admittances, and also the sum of apparent powers are equal to zero for the sound line. Phase shifts between currents at all terminals in the prefank stage, caused by the not synchronized samp~mg can also be calculated. An appropriate sum of currents at the tap point is also eqnal to zero under sound line conditions. The proposed methods are especially suitable for deteetion of faults with considerable impedances. Keywords:digital algorithms, line proteetio% power transmission lines, differential protectio~symmetrical components.

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