THE CHALLENGE OF MANAGING WATER AND MATERIAL BALANCES IN RELATION TO EUTROPHICATION

Eutrophication is the result of overfertilisation of the aquatic envir onment. In other words, the detrimental effects derived from increased anthropogenic release of nutrients to the environment. By modern conc epts of environmental abatement this is no longer only a question of i dentifying and purifying discharges. It is a question of keeping track of the system of nutrient mining, utilisation, recycle, transport, co nversion, containment and release in the modern society - in effect, t he total balance of nutrients in society. In Denmark, the point source s of nutrient release have been reduced by an order of magnitude. That has contributed to some improvements, but the diffuse sources have tu rned out to be more significant than originally expected. They are har der to reduce. That is why more integrated approaches have to be analy sed. Four approaches will be analysed: the DPSIR-approach, the 5-optio ns approach, the cause-effect relationship and the material balance an alysis. (C) 1998 IAWQ. Published by Elsevier Science Ltd.