Recent developments in surface and subsurface karst geomorphology: An introduction Jo De Waele a, ⁎, Lukas Plan b , Philippe Audra c a Dipartimento Scienze della Terra e Geologico-Ambientali, Via Zamboni 67, 40127 Bologna, Italy b Natural History Museum Vienna, Department for Karst and Caves, Museumsplatz 1/10,1010 Vienna, Austria c Polytech'Nice-Sophia Antipolis, Université de Nice-Sophia Antipolis, 1645 route des Lucioles, 06410 Biot, France abstract article info Article history: Accepted 18 September 2008 Available online 7 October 2008 Keywords: Karst Surface Subsurface Geomorphology Speleogenesis Where dissolution processes of bedrock dominate peculiar morphologies develop and overrule all landforms controlled by other surface processes. Pure karst landscapes are present in many parts of the world, but most of the time landscapes are shaped by a multitude of processes. The comprehension of the dissolution processes, that act both at the surface and underground, has developed rapidly in the last half century, although major achievements had already been reached at the end of the XIXth century. This special issue gives an overview of some of the most recent developments in surface and subsurface karst geomorphology and reviews where further studies should be fostered. © 2008 Elsevier B.V. All rights reserved. 1. Introduction Karst landscapes, in which dissolution of bedrock by water is the dominant geomorphic process, characterise almost 20% of the continents and more than a quarter of the Earth's population lives on or near karst areas (Ford and Williams, 2007). Typical karst topography is essentially related to subterranean drainage and therefore geomorphology and hydrology are closely interrelated. Karst geomorphology is a classic interdisciplinary scientific field in which Earth scientists, hydrologists, geographers, chemists, biologists, and other scientists can find their way towards a better understanding of the processes involved. Karst geomorphological surveys are becoming increasingly important in environmental impact assess- ment studies (Veni, 1999) or in the evaluation of disturbance in karst areas (Van Beynen and Townsend, 2005; De Waele, 2008). Karst and caves develop in many types of rock, including limestone, dolostone, gypsum, salt, quartzite, and some others. These rocks, subjected to different climates, assume many morphologies and landforms. Surface and subsurface karst morphology is a key to understand the nature and the genesis of cave and karst systems. All human activities in karst areas including every kind of construction, agriculture, fresh water supply, waste disposal – just to mention some – need detailed knowledge about karst systems. Modern techniques and modelling have brought new insight into karst processes and resulting landforms. This special issue tries to give an overview on what has been done and what is still to be done in karst geomorphology. 2. Karst geomorphology Karst geomorphology is the study of landforms, both at the surface and underground, that develop on soluble rocks by solution and associated processes. Karst landforms develop best on pure, dense and thick limestones and marbles. The name Karst is derived from the terms “Carso” and “Kras” used by local people to describe the stony landscape typical of the Classical Karst area (the area around Trieste and the Dinaric mountains of Slovenia) (Gams, 1993). The beginning of karst studies can be set at the end of the XIXth century, when a Serbian student of Albrecht Penck, Jovan Cvijić, published his PhD thesis entitled “Das Karstphänomen” (The phenomenon of Karst) at the school of geology and geography of Vienna (Cvijić, 1893). This was the first important karst geomorphological work that not only describes the karst landforms of the Classical Karst, but also refers to neighbouring areas with similar morphologies. Since then many authors have studied the peculiar karst landforms in many parts of the world, first independently in Europe and in North America, later also jointly. The reader is referred to several major textbooks on karst geomorphology for an overview (Bögli, 1960; Sweeting, 1981; Jennings, 1985; Trudgill, 1985; White, 1988; Ford and Williams, 1989, 2007), to the two recently published encyclopaedias (Culver and White, 2004; Gunn, 2004) or to the excellent review paper of Ford (2006). 2.1. Surface karst geomorphology Karst landscapes are dominated by dissolutional surface landforms produced by the dissolving of soluble rock by surface waters. The degree of dissolution depends on a number of factors including availability of water and its mode of recharge (diffuse, autogenic, and Geomorphology 106 (2009) 1–8 ⁎ Corresponding author. E-mail addresses: jo.dewaele@unibo.it (J. De Waele), lukas.plan@nhm-wien.ac.at (L. Plan), audra@unice.fr (P. Audra). Contents lists available at ScienceDirect Geomorphology journal homepage: www.elsevier.com/locate/geomorph 0169-555X/$ – see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.geomorph.2008.09.023