Molecular signatures of dissolved organic matter in a tropical karst system

摘要

Highlights?Ultra-high resolution analysis of DOM in karst systems using ESI-FT-ICR-MS.?Clear gradient between soil and cave, influence of biotic and abiotic processes.?Stalagmite DOM spectra retain part of the soil DOM fingerprint.?Important in-situ molecular components from microorganisms.AbstractKarst areas are widespread landforms present on all continents, formed by the dissolution of carbonate or evaporite host rock. Little is known about the composition and nature of dissolved organic matter (DOM) as it moves through karst systems, although karst DOM has been recognized as important for a range of natural processes. Microbial communities living in karst systems are some of the most diverse and intriguing on the planet, and their metabolism and life cycle can give clues related to the development of a host of different life forms. Karst areas are also of interest due to their mostly subterranean hydrology, an