Stikstofproblematiek van de akkerbouw en de melkveehouderij in het Mergelland; graslandonderzoek

anglais. The leaching of nitrate to the groundwater in some of the marly areas in southern Netherlands is unacceptably large and poses risks to the drinking water supply in the future. In south Limburg the nitrate content of the phreatic groundwater has risen sharply in recent decades. It is generally assumed that because the groundwater reserves are deep and the organic content of the soil is low, there is little – if any – denitrification in the marly areas. This means that all nitrogen applied but not taken up by the crop or fixed in the soil can be leached into the groundwater. In 1994, as part of the ROM project, research was initiated on the nitrogen problem in arable and livestock farming in the marly areas (Mergelland). The aim of this research was to establish the relationship between fertilisation and nitrate leaching on grass, maize and arable fields on loess soils and to indicate the cultivation and fertilisation measures necessary to achieve maximal emissions of 50 mg NO3/l and 25 mg NO3/l to the groundwater. The research consisted of an arable part and a grassland part. This report deals with the results of the latter

néerlandais; flamand. Het doel van dit onderzoek was de relatie tussen bemesting en nitraatuitspoeling op gras-, maos- en bouwland op lössgrond vast te stellen en aan te geven welke teelt- en bemestingsmaatregelen nodig zijn om een emissie van maximaal 50 mg NO3 /l en maximaal 25 mg NO3/l naar het grondwater te kunnen realiseren.