Ecology of glacier-fed rivers: current status and concepts

1. This paper is an introduction to a special issue of Freshwater Biology containing papers dealing with various aspects of the ecology of glacier-fed rivers. 2. Using similar field protocols, a wide range of glacier-fed systems were studied across Europe from the French Pyrenees to Svalbard within the framework of the European Commission project, Arctic and Alpine Stream Ecosystem Research (AASER). Recent investigations from other parts of Europe together with New Zealand and Greenland are also reported. This work has advanced our knowledge of the functioning of these types of rivers and has led to the modification and quantification of the conceptual model of Milner & Petts (1994). 3. Glacier-fed rivers, by virtue of the dominance of physical variables in shaping macroinvertebrate communities, are not only good indicators of climate change, but also may be suitable testing grounds for examining ecological concepts.