Middle to Late Holocene (8000 to 3000 years ago) Ostracode Assemblages in a Bahamian Sinkhole: Implications for Regional Hydroclimate
Abstract
Intensification and southern displacement of the North Atlantic Subtropical High (NASH) influences Caribbean rainfall. Additional hydroclimate records are needed from subtropical Caribbean latitudes to better understand how the NASH has impacted Holocene-scale subtropical rainfall. Sinkholes provide important sources of paleoenvironmental and paleohydrological information because their water column is influenced by regional rainfall, and their sediment records can be well preserved from a lack of physical and biological disturbances. Benthic ostracodes (aquatic crustaceans, meiofauna) are highly sensitive to aquatic conditions (e.g., salinity, oxygenation), and their shells become part of the sediment record after death. Thus, changes in sinkhole ostracode populations through time have great potential for monitoring long-term hydrographic change in sinkholes from local rainfall changes. Here we present ostracode assemblages from a 7-meter core taken from Emerald Pond, a small shallow northeastern Bahamian sinkhole. The assemblages indicate changes in groundwater salinity and water chemistry which further aid the understanding of Caribbean rainfall patterns. The distribution of these ostracode assemblages corroborates prior and current paleoecological interpretations of the northeastern Bahamas and indicate regional hydroclimate variability from 8000 to 3000 years ago.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMPP43B1606M
- Keywords:
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- 1620 Climate dynamics;
- GLOBAL CHANGE;
- 1627 Coupled models of the climate system;
- GLOBAL CHANGE;
- 4901 Abrupt/rapid climate change;
- PALEOCEANOGRAPHY;
- 4910 Astronomical forcing;
- PALEOCEANOGRAPHY