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Study included seven soils, an adjacent spring and brook and was conducted to estimate CH 4 source and sink strengths of forest soils along a wetness gradient, i.e. their exchange with atmosphere (direct emission), and hydrosphere (indirect emission). Soils are represented by anaerobic Histosol, oxic Cambisols, Histosol with degraded peatlayers and Gleysols having intermediate redox state. They could be separated into three emission groups: CH 4 emitting (248-318 kg C ha À1 a À1 ), CH 4 uptake (À0.1 to À5 kg C ha À1 a À1 ), and soils on the edge of CH 4 uptake and release (À0.2-20 kg C ha À1 a À1 ). Although soils with CH 4 uptake were dominant (75%), the soil specific CH 4 budget identified the study field (6.53 ha) as CH 4 source (40.9 kg C ha À1 a À1 ). Not only CH 4 emissions, but also dissolved CH 4 in soil solution varied regularly with soil type. Individual soil solutions contained 0.008-151 lmol CH 4 l À1 . CH 4 vanished to negligible loads, when dissolved CH 4 passed an oxidative downslope soil zone, but promoted CH 4 uptake was measured at this soil. In turn, CH 4 was discharged to the atmosphere, when the soil solution left the pedosphere across an anaerobic soil zone. These measured indirect emissions were low (34 g C a À1 ), but the values of individual soil solution indicate possible higher discharges (3.9 kg a À1 ) at a different soil pattern. The results suggest that CH 4 uptake rates of temperate forests are overestimated.

Abstract. Numerous studies have dealt with carbon (C) contents in Histosols, but there are no studies quantifying the relative importance of the individual C components in pore waters. For this study, measurements were taken of all the carbon components (particulate organic carbon, POC; dissolved organic carbon, DOC; dissolved inorganic carbon, DIC; dissolved methane, CH 4 ) in the soil pore water of calcareous fens under three different water management regimes (rewetted, deeply and moderately drained). Pore water was collected weekly or biweekly (April 2004 to April 2006 at depths between 10 and 150 cm.The main results obtained were:(1) DIC (94-280 mg C l −1 ) was the main C-component. (2) POC and DOC concentrations in the pore water (14-125 mg C l −1 vs. 41-95 mg C l −1 ) were pari passu. (3) Dissolved CH 4 was the smallest C component (0.005-0.9 mg C l −1 ). Interestingly, about 30% of the POM particles were colonized by microbes indicating that they are active in the internal C turnover. Certainly, both POC and DOC fractions are essential components of the C budget of peatlands. Furthermore, dissolved CO 2 in all forms of DIC appears to be an important part of peatland C-balance.

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