Résumé -Abstract - Zusammenfassung -:This first part, which is regional, consists of seven chapters
and describes the physical context and the caves explored in eight
counties located in Guizhou (Zhijin, Ziyun, Pingtang), Sichuan
(Wuxi) and Hubei province (Wufeng, Hefeng, Lichuan, Yichang).
Subtropical karsts are situated between 26 and 31° lat. N. Placed
on the left bank of Yangtse, in the Daba Shan, the Wuxi mountainous
area is on the boundary of subtropical and warm temperate climates,
but snow is frequent above 1000-1500 m high.
During speleological explorations, 57 km of passages have been surveyed mainly in great caves. Four caves are more than 5 km long. The longest are sink and resurgence systems. Theses often complex tunnel-caves offer affluents, sumps and several levels of passages as in the Gebihe (Ziyun/Guizhou) and Dadong-Longdong (Wufeng/Hubei) systems. During the summer monsoon, the underground discharges can be more than several tens of cumecs. So, it is necessary to explore between october-november and february-march. When the temporary sinkholes are situated in high valleys, the hydrologic potential is enough to form "alpine type" caves, but with important pressure tubes actively forming during the rainy season (Wuxi and Wufeng counties shafts).
Keywords: tunnel-cave, loss, spring, cave level, shaft, Guizhou, Sichuan, Hubei, Gebihe, Dadong.