Hydrological influence on the evolution of a subtropical mangrove ecosystem during the late Holocene from Babitonga Bay, Brazil

Mangroves are key ecosystems which respond to global changes in tropical and subtropical regions worldwide. We describe late Holocene mangroves that established close to the southernmost limit (28 degrees S) for this type of ecosystem in South America. Our findings are based on a C-14 dated core obtained from Babitonga Bay, Santa Catarina State, Brazil (26 degrees 12'S, 48 degrees 33'W). Analysis of palynology, sedimentary facies, isotopic and elemental data shows that mangrove establishment took place similar to 500 yrs. B.C.E., following an increase in humidity, and expanded further during the Roman Warm Period and at the end of Dark Age Cold Period. Mangrove and precipitation proxies records appear to be sensitive to rainfall patterns imposed both by the expansion/retraction of the Intertropical Convergence Zone and also the interaction with the South Atlantic Subtropical Anticyclone which affects coastal region due to sea surface temperature variations.

Automated summary

The study found that the late Holocene mangroves near Babitonga Bay in Santa Catarina State, Brazil, were established around 500 years B.C.E. following an increase in humidity, and were sensitive to precipitation patterns.