Effecten vernattingsmaatregelen op veenweidebedrijven in Noord-Holland : Technische en economische consequenties en effecten op bodemdaling en broeikasgasemissie

Model calculations have been used to explore the technical and economic consequences and effects on soil subsidence and greenhouse gas emissions for a dairy farm on peat soil in the province North Holland of The Netherlands (IPV project farm) of wetting measures. The wetting measures concerned pump-driven submerged drains with different target levels for the groundwater table (30, 40 and 50 cm below mowing field), ditch water level raising, trench infiltration and cattail cultivation and combinations of these measures, which are being experimented within the IPV project. The measures have been compared with a common situation with a ditch water level of 50 cm below mowing field. Apart from pump-controlled submerged drains with a target level for the groundwater table of 50 cm below mowing field, all waterlogging measures and combinations of measures led to extra waterlogging and loss of grass production, which in particular increased the costs for feed purchase. As a result, the economic operating result can be drastically reduced. Pump-driven submerged drains with a target groundwater level of 30 cm below ground level and trench infiltration at a trench distance of 12,5 m gave the largest estimated reduction in ground level subsidence and greenhouse gas emissions (CO2 en N2O). Trench infiltration appears to be more cost effective, given the high cost of pump-controlled submerged drains.