Karst caves are scarce and valuable natural resources of enormous economic significance. Normally, cave inner environment remains subtly stable; however, inappropriate exploitation may lead to ecological changes, even destruction of the landscape. Hu-Tian Palace, a well-known karst cave in China, is a typical case. After storing liquor for years, a thick layer of materials appeared on stalactites and gradually changed color from ivory to dark brown. Microscope observation reveals that samples from stalactites surface seemed to be created by microorganisms. With further isolation, purification and 16sDNA taxonomy, four Gram positive bacteria were identified. Our results show that discoloration of stalactites is caused by over breeding of microorganisms due to prolonged storage of liquor.

Scientific field

Biology

Country

China

Contestants

Letian XIAO