Nutrient mobilisation and losses related to the groundwater level in low peat soils
The changes in dissolved organic carbon (DOC), N-NO3, N-NH4 and P-PO4 concentrations in response to fluctuations in the groundwater table were investigated in the peatlands of Biebrza National Park and some of its surrounding sites. The lowering of the groundwater table during summer time was accompanied by an increase in P-PO4 and N-NH4 concentrations, and in some cases they were exceptionally high compared with undisturbed water. Concentrations of both nutrients correlated with groundwater levels. Decreasing the groundwater level promoted higher concentrations of both nutrients. Nevertheless, elevated concentrations of P-PO4 and N-NH4 occurred in groundwater during the summer months when the outflow of water from peatland was slow. The N-NO3 and DOC concentrations did not change markedly with the lowering of groundwater table or during different seasons.
Keywords: nutrients, groundwater levels, peatland, dissolved organic carbon, seasonal variations, phosphorus, ammonium, nitrate, peat soil, nutrient mobilisation, nutrient losses, Poland, environmental pollution