Page 236 - Fundamentals of Geomorphology

KARST LANDSCAPES 219

of the inherent scientific interest of karst landscapes. At formations or speleothems, material weathered in situ,
the regional level, 121 karst areas, covering 18,441 km 2 and clastic sediments carried into caves and laid down
or 14.3 per cent of the total karst, are afforded pro- there. Speleothems are multifarious, and may be grouped
tected area status. Higher levels of protection are found into dripstones (such as stalactites and stalagmites),
in Cuba, the Dominican Republic, and the Bahamas. eccentric forms (such as helictites and moonmilk), and
Lower levels of protection occur in Jamaica, Puerto Rico, subaqueous forms (such as rimstone pools and gours).
Trinidad, and the Netherlands Antilles, and minimal pro- Agricultural practices have led to the stripping of soil
tection is established in the smaller islands. In Trinidad from some karst areas. The fascination of caves has pro-
and Tobago, for instance, karst forms comprise karren, duced a thriving cave tourist industry, but cave visitors
caves, springs, valley systems, and a range of sinkholes, may destroy the features they come to view. Karstlands,
including an area of polygonal cockpit karst (Day and too, are threatened in many parts of the world and require
Chenoweth 2004). Quarrying, and to a lesser degree log- protection.
ging and agriculture, have destroyed much of the karst in
westernTrinidad, whilst urban development and tourism
have added to the damage in Trinidad and in the low- ESSAY QUESTIONS
lands of western Tobago. Little of these karstlands lie
within existing protected areas. 1 How distinctive are karst landscapes?
2 Discuss the role of climate in karst
SUMMARY formation.
3 Analyse the problems of karst
Karst is terrain with scant surface drainage, thin and management.
patchy soils, closed depressions, and caves. Its distinctive
features develop on fairly pure limestones, but also occur
inevaporitesandsilicaterocks.Itformsbythedissolution
of limestone or other soluble rocks, in conjunction FURTHER READING
with creep, block slumps, debris slides, earthflows, soil-
falls, rockfalls, block slides, and rock slides. Fluvial and Ford, D. C. and Williams, P. W. (1989) Karst Geomor-
hydrothermal processes may affect karst development. phology and Hydrology. London: Chapman & Hall.
A multitude of landforms form on limestone: karren An excellent book on karst. A new edition, to be
of many shapes and sizes, limestone pavements, pin- published by John Wiley & Sons, will appear in 2007.
nacles, karst ruins, corridors, and coastal karst features; Gillieson, D. (1996) Caves: Processes, Development and
also, a range of closed depressions: dolines, karst win- Management. Oxford: Blackwell.
dows, uvalas, and polja. Cone karst is a tropical form A superb book on subterranean karst that includes
of karst, two varieties of which are cockpit karst and chapters on management.
tower karst. Labyrinth karst is an extratropical version
of tower karst. Despite a scarcity of surface drainage in Jennings, J. N. (1985) Karst Geomorphology. Oxford and
karst terrain, fluvial processes affect some karst land- New York: Blackwell.
forms, including gorges, blind and half-blind valleys, A classic by an author whose name is synonymous with
steepheads, dry valleys, meander caves, natural bridges, karst geomorphology. A little dated but may still be read
and tufa and travertine deposits. Another multitude of with profit.
landforms forms within limestone in subterranean karst. Trudgill, S. (1985) Limestone Geomorphology. Harlow,
Speleogens are erosional forms in caves. They include Essex: Longman.
potholes and current-markings, rock pendants and scal- Includes a good discussion of karst processes.
lops. Within caves, three types of deposit are found: cave