Study of Weathering Carbonate Rock by Rock Microorganism
|Keywords||Microorganism Carbonate Weathering processes Weathering mechanism|
Our country is the the carbonate rocks largest country in the world, due to the slow rate of dissolution of carbonate rock weathering, soil formation rate is slower, and carbonate rock area of ??thin soil layer, combined with poor earth and rock, the rainfall is more abundant precipitation for long periods of time, the situation of serious soil erosion, resulting in the carbonate rocks rocky desertification area has become increasingly serious, so it is very important to study the weathering of carbonate rocks. In this paper, 101 strains of microorganisms isolated and purified from the carbonate rocks, use of calcium carbonate weathering the test filter out the the weathering efficient a bacteria F8B008 (Bacillus licheniformis Bacillus licheniformis) and a fungal FeM001 (Aspergillus genus Aspergillus sp. ). The process and mechanism of these two microbial weathering of carbonate rocks, explore the efficient application of the microorganisms in the weathering of carbonate rocks. Liquid culture method to study the role of the three bacterial and three fungal carbonate weathering, the results indicate that microorganisms can promote the weathering of carbonate rocks, there are differences carbonate weathering rates between different microorganisms, roughly show the fungus (FeM001 gt; FeM002 gt; BYwM020) gt; bacteria (BYB013 gt; F8B008 the gt; GZKB01) trend. The role of temperature and mechanical weathering of carbonate Ca2 concentration in the first 10d 20-30ug/mL between; inorganic acid weathering of carbonate rocks representing people, taking into account the wide distribution of microorganisms and amazing reproductive capacity, microbial weathering of carbonate rocks is much larger than the chemical weathering of carbonate rocks on the basis of existing research results. The carbonate rocks the microbial weathering process research found that the fungal weathering of carbonate rocks adsorption parcels bacteria by adsorption mainly caused by fungi on the weathering of carbonate rocks generally greater than bacteria, microbial the carbonate package or adsorption ability affect an important factor in the strength of the weathering of carbonate rocks; inoculum size, the number of bacteria adapter, reproductive capacity of the microbial growth rate, addicted carbonate lithology and so are the influencing factors of microbial weathering of carbonate rocks. Microbial metabolites carbonate weathering strong role (the weathering efficiency of more than 30 ‰), citric acid and kojic acid carbonate weathering acetic acid carbonate weathering obvious; lactose, polysaccharides on the efficiency of the weathering of carbonate rocks were: 0.09 ‰, 4.95 ‰; lactose weathering of carbonate rocks insignificant polysaccharide role of carbonate weathering (weathering efficiency of about 5 ‰ ); microorganisms produced carbonated Russian anhydrase promote the weathering of carbonate rocks and probably microbial protein from the weathering of carbonate rocks in protein. The experiment also showed that external factors, such as mechanical action, temperature and pH are microorganisms weathering carbonate rocks of the important factors. The papers from the angle of the geological microorganisms and microbial geochemistry explore microbial weathering of carbonate rocks, provides the basic data for the research in this field, the research results to enhance the understanding of the process and mechanism of microbial weathering of carbonate rocks and carbonate rocky desertification control provides a new way of thinking.