The effect of drainage on nutrient release from fen peat and its implications for water quality ?a laboratory simulation

Abstract

The effect of peat moisture status on N, S, Ca, and Mg release to drainage waters was examined using a constant temperature laboratory incubation. Peat samples originating from drained and undrained sites in West Sedgemoor, Somerset Levels, SW England were compared. Three treatments: long term waterlogging, aeration, and fluctuating aeration and waterlogging were imposed on all peat samples. These treatments resulted in different rates and total amounts of N, S, Ca, and Mg release, with waterlogging resulting in highest solute release. The total amounts and rates of release of S, Ca, and Mg from peat that was undrained prior to incubation always exceeded that from drained site peat samples regardless of peat moisture status. Although the degree of waterlogging or aeration affected the rate and total amount of watersoluble N released during incubation, there was no difference between peat that was drained, and peat that was undrained, prior to incubation. Drainage of currently undrained and waterlogged peat in West Sedgemoor will result in the transfer of high concentrations of S, Ca, and Mg from the peat to the drainage ditch.