Supplementary Issues of Zeitschrift für Geomorphologie publishes volumes devoted to a particular topic or problem group in geomorphological research. Prior to 2008 Supplement volumes were consecutively numbered (suppl. vols. 1-148). As of 2007 the numbering scheme has changed and now carries the volume number of corresponding main series volume, supplemented with the a supplement issue number (e.g. Volume 55, Supplementary Issue 1).