According to the EU definition (Guidance for the analysis of pressures and impacts in accordance with Water Framework Directive, EU 2002) the term Pressures is: "The direct effect of the driver". Modelling of diffuse nutrient losses, i.e. nitrogen and phosphorous, have been the main focus of the EUROHARP project. Diffuse N and P losses represent important pressures linked to agricultural activities.The behaviour and the impacts of Nitrogen and Phosphorous in the environment depend strongly on their bio-geo-chemical properties. The EUROHARP project has not carried out studies on the fundamentals of the N and P transformation processes. However, these processes are to a varying degree of detail included in different Quantification Tools applied in the EUROHARP project. To find out more about which processes are included in the EUROHARP Quantification Tools you can study the description of the Quantification Tools or make a search based on which nutrient forms are most relevant in your case. You may also evaluate how well nutrient losses were estimated by different QTs in European catchments.