Chapter 5: Quality of karst waters

Résumé - Abstract - Zusammenfassung :The mountainous karst regions of Central China are densely populated (200 inhabitants/square km). What is the water quality in such a crowded region? During the speleological expeditions GEBIHE 89 and DONGHE 92, three kinds of pollution caused by man were investigated, namely agriculture, waste water and industrial seepage. The well known agricultural pollution by nitrates is insignificant due to limited use of chemical fertilisers by Chinese farmers. Strong bacterial pollution of waste water is widespread because the population is widely scattered in the mountains. Even small springs contain faecal bacteria. In the region only few large industrial plants exist and therefore the chemical pollution level is not high. Due to the lack of environmental authority, however, the current development of small scale private industry is critical, as can be seen by the example of the numerous small scale coal mines which cause a very high level of pollution by heavy metals.

Keywords: Karst, water quality, China, agriculture, nitrate, coliform bacteria, coal mine, heavy metals.