Understanding the linkage between regional climatology and cave geochemical parameters to calibrate speleothem proxies in Madagascar.

摘要: Abstract Robust reconstructions of paleoclimate and paleoenvironmental changes using stalagmite proxy records critically depend on detailed observations the transfer function between regional climate/environment, karst aquifer hydrology, finally cave microclimate via monitoring, which is currently lacking in Madagascar. This paper reports first monitoring study performed Anjohibe Cave, Mahajanga, NW Madagascar to understand linkage climatological responses such changes. In this research, we monitored (1) drip water pH, TDS, EC, temperature, δ13CDIC, δ18Ow, δ2Hw, elemental (Ca, Mg, Sr) composition, (2) atmosphere pCO2, relative humidity (RH) temperature. Three significant findings were drawn from results. First, data show that air-to-air fast, internal parameters closely vary with climatology. Second, rainfall signal not immediate, it can take few months one season for signals be detected due “epikarst storage effect”. Lastly, CaCO3 precipitation likely occur during winter-summer transition, prior carbonate was detected. Since growth speleothems influenced by numerous cave-specific factors, study, although preliminary, indicates Cave waters are capable registering its surrounding environment. Such information ultimately archived reconstruct Results research will high significance those working within Madagascar, understanding climatic variations deposits.