Название: MICROBIALLY INDUCED CALCITIC MOONMILK DEPOSITS LEAD TO INHIBITION OF MICROBIAL ACTIVITY IN CAVES
Источник: 15th International Congress of Speleology
Место публикации: Spain
Том:
Выпуск:
Страницы: 378-380
Web/Url:
№ полки:
Добавлено: Elmaz
Ключевые слова: MICROBIAL ACTIVITY, CAVES, микробиология, лунное молоко, формирование отложений
Источник:
Реферат: A decisive role for microorganisms in the formation of calcitic moonmilk deposits has been previously suggested. A model of stepwise formation of these deposits was based on morphological evidence of microbial colonization of rock surfaces followed by calcite deposition over the microbial communities, microstructural breakdown, and accumulation of collapsed fibers. Aiming to verify the proposed model, a combination of techniques such as microbial activity estimates stable isotope analyses and petrographic examination were used to study the role of microbial communities on specific types of carbonate deposits. Results from this study complement the previous model suggesting that moonmilk consists of stacked layers of mineral deposits directly induced by microbial activity. However, these calcite-based deposits produce microbial growth inhibition leading to a progressive decay of microbial activity as the mineralization accumulates. These results are in agreement with former results reporting a progressive entombment of microorganisms, mainly bacteria, involved in the induction of carbonate crystal growth.