Dynamika wahań poziomu wody na zdegradowanych torfowiskach bałtyckich
Abstract
Diversity of water level fluctuations in degraded Baltic raised bogs.
A b s t r a c t. Baltic-type raised bog (dome-shaped) is a type of peatbog with predominant atmospheric water supply and a convex shape, known as the dome. In Poland, 72 Baltic peatbogs have been distinguished, with various degrees of transformation, in the coastal zone and lake districts of the South Baltic Sea. None of them has natural water conditions. Their common name indicates significant similarities due to water supply conditions. However, due to the differences in morphology, both primary and secondary (resulting from the different course and scale of anthropogenic transformations), they may be expected to show some variability within the subtype. The aim of the paper is to present the diversity of water-level fluctuations in degraded Baltic raised bogs. An attempt was made to answer the question how strong the diversity of fluctuations is, both within each object and between two objects situated close to each other. Moreover, speed and value of the response of water level to atmospheric precipitation were analysed. The spatial scope of the paper covers two Baltic raised bogs in the lower part of the Łeba River valley: Czarne Bagno and Łebskie Bagno. To answer the questions asked, the results of measurements of water level and precipitation on the peat bogs were used. The study found that both the bogs show high dynamics in the variation of groundwater level. Lowering of the water level on both peatlands has always been recorded in the summer months, whilst its increase, which lasted until spring, has been observed in autumn. The water retention amount and water level on the peatlands were influenced primarily by precipitation. Extreme meteorological conditions that make it less conspicuous is the variation resulting from factors such as location in different parts of the bog, or type of degradation.
A b s t r a c t. Baltic-type raised bog (dome-shaped) is a type of peatbog with predominant atmospheric water supply and a convex shape, known as the dome. In Poland, 72 Baltic peatbogs have been distinguished, with various degrees of transformation, in the coastal zone and lake districts of the South Baltic Sea. None of them has natural water conditions. Their common name indicates significant similarities due to water supply conditions. However, due to the differences in morphology, both primary and secondary (resulting from the different course and scale of anthropogenic transformations), they may be expected to show some variability within the subtype. The aim of the paper is to present the diversity of water-level fluctuations in degraded Baltic raised bogs. An attempt was made to answer the question how strong the diversity of fluctuations is, both within each object and between two objects situated close to each other. Moreover, speed and value of the response of water level to atmospheric precipitation were analysed. The spatial scope of the paper covers two Baltic raised bogs in the lower part of the Łeba River valley: Czarne Bagno and Łebskie Bagno. To answer the questions asked, the results of measurements of water level and precipitation on the peat bogs were used. The study found that both the bogs show high dynamics in the variation of groundwater level. Lowering of the water level on both peatlands has always been recorded in the summer months, whilst its increase, which lasted until spring, has been observed in autumn. The water retention amount and water level on the peatlands were influenced primarily by precipitation. Extreme meteorological conditions that make it less conspicuous is the variation resulting from factors such as location in different parts of the bog, or type of degradation.