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KARST LANDSCAPES 217

air temperatures by up to 3 C. A party of tourists and lampenflora but also damages the speleothems.
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in Altamira Cave, Spain, increased air temperature A partial solution is to provide plastic mesh walkways
by 2 C, trebled the carbon dioxide content from at cave entrances and for tourists to wear protective
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0.4 per cent to 1.2 per cent, and reduced the relative clothing. Recreational cavers may also adversely affect
humidity from 90 per cent to 75 per cent. All these caves (Gillieson 1996, 246–7). They do so by carbide
changes led to widespread flaking of the cave walls, dumping and the marking of walls; the compaction of
which affected the prehistoric wall paintings (Gillieson sediments with its concomitant effects on cave hydrol-
1996, 242). A prolonged increase in carbon dioxide ogy and fauna; the erosion of rock surfaces in ladder
levels in caves can upset the equilibria of speleothems and rope grooves and direct lowering by foot traffic; the
and result in solution, especially in poorly ventilated introduction of energy sources from mud on clothes
caves with low concentrations of the calcium ion in and foot residues; the introduction of faeces and urine;
drip water (Baker and Genty 1998). Other reported the widening of entrances and passages by traffic or
effects of cave tourism include the colonization of green by digging; and the performing of cave vandalism and
plants (mainly algae, mosses, and ferns) around con- graffiti. The best way of limiting the impact of cave
tinuous lighting, which is knows as lampenflora, and a users is through education and the development of
layer of dust on speleothems (lint from clothing, dead minimal-impactcodes,whichfollowcavemanagement
skin cells, fungal spores, insects, and inorganic mate- plans drawn up by speleologists, to ensure responsible
rial). The cleaning of cave formations removes the dust conduct (see Glasser and Barber 1995).

Managing karst
Limestone and marble are quarried around the world
Karst management is based on an understanding of and used for cement manufacture, for high-grade build-
karst geomorphology, hydrology, biology, and ecology. ing stones, for agricultural lime, and for abrasives.
It has to consider surface and subsurface processes, since Limestone mining mars karst scenery, causes water
the two are intimately linked. The basic aims of karst pollution, and produces much dust. Quarrying has
management are to maintain the natural quality and destroyed some British limestone caves and threatens to
quantity of water and air movement through the land- destroy others. In southern China, many small quarries
scape, given the prevailing climatic and biotic conditions. in the Guilin tower karst extract limestone for cement
The flux of carbon dioxide from the air, through the soils, manufactories and for industrial fluxes. In combination
to cave passages is a crucial karst process that must be with vegetation removal and acid rain from coal burning,
addressed in management plans. In particular, the system thequarryinghasscarredmanyofthekarsttowersaround
that produces high levels of carbon dioxide in soil, which Guilin city, which rise from the alluvial plain of the Li
depends upon plant root respiration, microbial activity, River. It is ironic that much of the cement is used to build
and a thriving soil invertebrate fauna, needs to be kept hotels and shops for the tourists coming to see the lime-
running smoothly. stone towers. In central Queensland, Australia, Mount
Many pollutants enter cave systems from domestic Etna is a limestone mountain containing forty-six named
and municipal, agricultural, constructional and min- caves, many of which are famous for their spectacular
ing, and industrial sources. In Britain, 1,458 licensed formations. The caves are home to some half a million
landfill sites are located on limestone, many of which take insectivorous bats, including the rare ghost bat (Macro-
industrial wastes. Material leached from these sites may derma gigas). The mining of Mount Etna by the Central
travel to contaminate underground streams and springs Queensland Cement Company has destroyed or affected
for several kilometres. Sewage pollution is also common many well-decorated caves. A public outcry led to part of
in British karst areas (Chapman 1993). the mountain being declared a reserve in 1988, although