U.S. Environmental Protection Agency
EPA Science Advisory Board
Background Information


Document NameTime scales of nutrient losses from land to sea—a European perspective.
Document AuthorGrimvall, A.
Stålnacke, P.
Tonderski, A.
Short DescriptionEcol. Engineering, 14, 363-371.
CategorySubgroup 3: Scientific Basis for Goals and Management Options
Publication Year2000
Text:

Abstract: Empirical data regarding the time scales of nutrient losses from soil to water and land to sea were reviewed. The appearance of strongly elevated concentrations of nitrogen and phosphorus in major European rivers was found to be primarily a post-war phenomenon. However. the relatively rapid water quality response to increased point source emissions and intensified agriculture does not imply that the reaction to decreased emissions will be equally rapid. Long-term fertilisation experiments have shown that important processes in the large-scale turnover of nitrogen operate on a time scale of decades up to at least a century, and in several major Eastern European rivers there is a remarkable lack of response to the dramatic decrease in the use of commercial fertilisers that started in the late 1980s. In Western Europe, studies of decreased phosphorus emissions have shown that riverine loads of this element can be rapidly reduced from high to moderate levels, whereas a further reduction, if achieved at all, may take decades. Together, the reviewed studies showed that the inertia of the systems that control the loss of nutrients from land to sea was underestimated when the present goal of a 50% reduction of the input of nutrients to the Baltic Sea and the North Sea was adopted.