Environmental problems in karst regions have become an
important topic in international geographical environment
research (Beach et al. 2008; Parise et al. 2008; Ducci et al.
2008). About 15% of the world area, including southern
Central Europe, eastern North America and southwestern
China is covered by karst landscapes. The karst region in
southwestern China is famous for its large area, level of
development and fragile ecological environment (Yang
et al. 2007). The carbonate rock outcrop in this region has
an area of 4.26 9 105 km2, and is mainly distributed in the
provinces of Yunnan and Guizhou as well as the Guangxi
Autonomous Region. The area has a subtropical moist
monsoon climate with annual mean precipitation of 850–
1,600 mm. Its unique dual three-dimensional spatial
structure controls the transformation of rainfall, surface
water and groundwater and the formation process of water
resources (Wang and Shi 2006). This kind of structure
often forms a complex fracture–fissure and fissure–conduit
karst hydrological system (Yuan 1993).