Applied hydro-ecological science for the twenty-first century

In this paper we provide an overview of the need for sound science on which to base decisions in regulated river management. A tool-box of techniques for informing such decisions is introduced, in the context of various, mostly recent, institutional developments. These have given management agencies more powers to manage river flows in an integrated way. We review the underpinning science of applied hydro-ecology, noting that not only is our knowledge incomplete but also there are barriers (not least financial) in its day-to-day application. We then go on to highlight common themes arising from the accompanying group of papers, and to link them to a broader context of applied hydro-ecology. These papers arose from the workshop on "Riverine Ecological Response to Changes in Hydrological Regime, Sediment Transport and Nutrient Loading", held at the IUGG congress in 1999.