Change of peat mass during decomposition in mires of Poland and West Siberia

The paper presents the results of field experiment on peat decomposition in peat deposits of mires in West Siberia and Poland. Two principal factors determining the dynamics of peat mass are revealed: position in relief and contribution from the below ground organs of herbaceous plants. In a raised bog, an upland microlandscape, maximum values of peat mass loss were obtained in the upper layer of peat and minimum values in the lower layer. In all poor fen ecosystems which are lowland microlandscapes, similar values of peat mass losses at different depths were obtained. In mire ecosystems with a considerable proportion of grasses in the phytocenosis, the supply of peat in the upper half-meter layer is replenished by dead below ground organs of plants.