Experimental Study On Roles Of Different Kinds Of Typical Microbes In The Corrosion Of Limestone

The dynamic and effects of corrosion acted by the typical bacteria, fungi and actinomycete, which were separated from soils in karst areas of Southwest China, were studied by simulated experiments of shake flasks and soil columns. Also, the effects of different kinds of typical microbes on elements migration of Ca, Mg and Zn in soil-limestone systems were researched, and the corrosion mechanisms of fungi were preliminarily discussed.Some results were obtained as follows. (1) Typical bacteria, fungi and actinomycete used in the experiments had stronger influences on limestone corrosion, but there were differences in corrosion effects of limestone among different kinds of microbes, and the surface shape of limestone varied with different kinds of microbes. Among three kinds of microbes in simulated experiments of shake flasks and soil columns, fungi had the most significant corrosion effect, and the next were actinomycete and bacteria. (2) The effects of three kinds of typical microbes on migration of different elements were different. For the migration of Zn2+ and Ca2+, fungi>actinomycete>bacteria>non-microbial control; for the migration of Mg2+, bacteria > Fungi > Actinomycete > non-microbial control. (3) Temperature had different degrees of improving effects on elements migration of Ca, Mg and Zn. (4) There was a certain correlation between the mean activity of carbonic anhydrase (CA) in leachates of soil columns and the total amount of Ca2+, Mg2+ and Zn2+ in leachates. This showed that CA had a certain influence on the migration of these three kinds elements, and that the influence varied with different elements. (5) The acidic materials and CA like enzymatic materials excreted by fungi and the enwraping effect of fungal mycelium were important factors of influencing corrosion effects. The corrosion effect from great to small were enwraping effect>acidic effect>enzymatic effect of CA. _________________ different kinds of microbes in biokarst and element migration in karst systems, and deep studies on the corrosion mechanisms and element migration mechanisms of microbes in karst systems.