Solute transfer from drained fen peat

The relationship between peat hydrophysical properties and solute transfer to drainage ditches was examined for a pump-drained soligenous valley fen in SW England. Drainage increased the bulk density and lowered the hydraulic conductivity of the peat, to the extent that, water table drawdown could not be detected beyond 5 m from the drainage ditch or field drains. The water table drawdown zone acted as the source of solutes transfered to the drainage ditch on pumping. A distinct solute release sequence was recorded in the drainage ditch, with SO₄-S peaking before NH₄-N, which was followed by Ca, Mg and NO₃-N. Ca and Mg release was delayed by up two days following a pump event. Solute concentrations in pump-drained ditches were significantly higher than those of drainage channels unaffected by pumping. Solute transfer from the peat as a result of pump drainage, has resulted in water quality deterioration within the peatland.