This
contribution brings to a close a special issue of Hydrology and Earth System
Sciences concerning the assessment of nitrogen dynamics in catchments across
Europe within a semi-distributed Integrated Nitrogen model for multiple source
assessment in Catchments (INCA). The wide range of issues involved in relation
to hydrology and within-catchment processes, scale (from small catchments to
major river basins), climate (from sub-arctic to Mediterranean regimes) and
pollution (atmospheric, agricultural and urban sources) is outlined.
Consideration is then given to how well the model has performed and future
research requirements are outlined.
Keywords: nitrogen, nitrate, ammonium, organic nitrogen, catchments, streams,
rivers, river basins |