Water quality in cutaway peatland lakes in Seda mire, Latvia

Transformation into shallow lakes can be a major post-harvesting land-use option for cutaway peatlands. The aim of our study was to analyse factors influencing water quality and communities on lakes created in a cutaway bog in the Seda Mire, Latvia. The residual peat amount and the lake feeding conditions (the balance between ground water and inflow from adjacent river during the spring season) were found to be major factors influencing aquatic chemistry and studied habitats. The studied cutaway lakes cannot be considered as typical bog lakes regarding hydrochemical composition (especially regarding concentrations of major dissolved ions, pH and water colour) and hydrobiological features (metabolic activity, biomass and number of species of phytoplankton and zoobenthos). Considering aquatic chemistry and community structure of the cutaway lakes, a recommendation was made in respect to peat excavation to transform peat mining sites to lakes.