Vegetation and Hydrology in a Spring Mire Complex in Western Pomerania, Poland

The vegetation of one of the largest spring mires in Poland has been studied with special regard to hydrological conditions and stratigraphic development of the mire. Despite its biotic richness the mire is in a slow state of deterioration, initiated by man several hundred years ago. Evidence has been found that drainage occurred in an originally treeless percolating mire (sloping fen), possibly as a result of hydrological changes in a lower lying lake. The development of the springs was probably a reaction to the increased resistance to water flow in the percolating mire, forcing the groundwater to discharge high up at the sand borders. The eroding effect of the spring water courses increased the drainage and, although the springs also provided new habitats for rare moss communities, a considerable eutrophication in the present spring alder wood can be noticed.