The EU Water Framework Directive is the most significant piece of European water legislation for over 20 years with regards to surface waters. The Directive requires assessment of impacts brought about by human activities on the environment by the end of 2004. This is the start of a process that will be used to identify waterbodies at risk of failing to meet their environmental objectives set by the Directive.
The nutrient status of surface waters and the processes driving nutrient mobility within river basins play a major role in defining environmental quality objectives. This volume brings together over 30 original research papers plus this introduction and a conclusion to provide a focus on process-driven science as a critical review of the requirements of the Water Framework Directive. The intention is that the collective research described here helps to identify current understanding and gaps in current research that might be identified and addressed to fulfil the requirements of the Directive. Most of the papers deal with nitrogen or phosphorus or both, but there are also papers linked to silicon and carbon as they are important either directly or indirectly for nutrient dynamics and/or their control. The papers cover research ranging from evaluating the role of hydrological processes in the delivery of nutrients to surface waters, defining the linkages between spatial and temporal controls on nutrient sources and impacts of nutrients in river basins, and risk assessment methodologies to classify those river basins requiring priority action.
After a scene-setting first paper (Harris and Heathwaite), the papers divide into three sections: (1) process measurement, (2) trend analysis, and (3) modelling and decision-support systems. The river basins considered in this special issue have extensive European coverage from Finland, Norway and Estonia through to the Mediterranean and from the maritime Atlantic through to central continental Europe. The measurement section is comprised of 10 papers and they are organised according to geographical location to give an overview of current process understanding and measurement practices (Jordan et al.; Kurz et al.; Jarvie et al.; Neal et al., a,b; Rekolainen et al.; Wood et al.; Lazzarotto et al.; Gelbrecht et al.; Torecilla et al.). The coverage extends from Ireland to Switzerland and NE Germany to Spain. The trend analysis section comprises 11 papers (Donahue et al.; Smith et al.; Rekolainen et al.; Neal et al.; (two papers), Littlewood and Marsh; Bechmann et al.; Granlund et al.; Iital et al.; Kronvang et al.; Oenema et al.; Grizzetti et al.). These are located across a range of drainage basins. They comprise Lough Mask, Republic of Ireland; the inland and coastal waters of Northern Ireland; Plynlimon, Wales; Finland; the aggregated freshwater-monitoring area of Great Britain; Aker Lake system, Norway; coastal river basins in southern Finland; Lake Peipsi (Estonia); Danish streams, lakes and coastal waters; groundwater and surface waters of the Netherlands; and the Wash (UK), Zelivka (Czech Republic) and Vilane (France) river basins. The remaining 11 papers (Jordan and Smith; Brazier et al.; Kyllmar et al.; Andersen et al.; Smith et al.; Cugier et al.; Garnier et al.; Wade et al.; Hughes et al.; Heathwaite et al.; Fassio et al.) deal essentially with modelling and these subdivide into three types of analysis. First, export coefficients are examined as a basic tool in agricultural land use management. The models described in this sub-section have been developed for Northern Ireland, the UK, Sweden and Denmark. The second group of four modelling papers deals much more at a mechanistic level of analysis covering river basins in the UK, France and Europe-wide, whilst the final group of three papers deal essentially with decision-support tools of varying degrees of sophistication. The work is brought together in a concluding paper (Neal and Heathwaite). It identifies, based on the papers collected here, the gaps in knowledge, key research needs for the integrated analysis of nutrients in river basins and their management under the guise of meeting the needs of the Water Framework Directive.