- EveNFlow (N)

EveNFlow is a semi-distributed model with five modular components. The system developed uses as input statistical data on land use, farming practices, climate and soil characteristics, collated at a spatial resolution of one square kilometer as a National Environment Database. The components of EvenFlow incorporate a number of simple meta-models that are adapted to the scale and information content of the environment database. The model concerns only diffuse inputs, effluent contributions to the river nitrate load are estimated either on the basis of catchment population figures and per capita estimates of effluent volumes and nitrogen load, or information on licensed dry weather flow discharges.

• Component 1 is a soil nitrate model that simulates the soil crop interaction that control the mass of nitrate present in the soil at the onset of winter drainage that is vulnerable to leaching.
• Component 2 is a soil drainage model.
• Component 3 is a leaching function that predicts the cumulative proportion of available nitrogen that is leached as a function of rainfall and soil water content.
• Component 4 is a drainage routing model.
• Component 5 concerns nitrate retention.