The mechanism and magnitude of nitrate leaching from grassland on a heavy clay soil were investigated by measuring nitrogen input, and nitrate concentrations in groundwater and drain discharge for two years. A bromide tracer was applied to study solute transport mechanisms. Nitrate transport in the heavy clay soil mainly occurred via preferential flow through mesopores and macropores, resulting in low mobile-water volumes and high nitrate-leaching rates. Nitrate concentrations in the drain discharge were high. The present generation of computer simulation models for nitrogen transport and behaviour in soils cannot adequately predict nitrate leaching in heavy clay soils.
|Title of host publication||Modelling the fate of agrochemicals and fertilizers in the environment|
|Editors||C. Giupponi, A. Marani, F. Morari|
|Publication status||Published - 1995|