0000000000453914
AUTHOR
Leonardo Langone
Reconstructing Bioinvasion Dynamics Through Micropaleontologic Analysis Highlights the Role of Temperature Change as a Driver of Alien Foraminifera Invasion
Invasive alien species threaten biodiversity and ecosystem structure and functioning, but incomplete assessments of their origins and temporal trends impair our ability to understand the relative importance of different factors driving invasion success. Continuous time-series are needed to assess invasion dynamics, but such data are usually difficult to obtain, especially in the case of small-sized taxa that may remain undetected for several decades. In this study, we show how micropaleontologic analysis of sedimentary cores coupled with radiometric dating can be used to date the first arrival and to reconstruct temporal trends of foraminiferal species, focusing on the alien Amphistegina lo…
Chronological records of metal deposition in sediments from the Strait of Sicily, central Mediterranean: assessing natural fluxes and anthropogenic alteration
Abstract Sediment box-cores were recovered from the Strait of Sicily along two onshore–offshore transects in water depths of 29–500 m. Samples were dated by 210 Pb and analysed for major and trace elements. Inspections of chronological profiles integrated with application of statistical algorithms to the geochemical dataset and supported by in situ hydrological observations were used to assess factors driving element distributions. Mineralogical and chemical variability of sediments offshore of the southwestern Sicily coast reflect the irregular sea floor morphology of the Adventure Bank. Anthropogenic inputs explain enrichments with respect to background values for Sb, As, Pb, and Hg, that…
Mediterranean circulation perturbations over the last five centuries: Relevance to past Eastern Mediterranean Transient-type events
The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910 ± 12, 1812 ± 18, 1725 ± 25 and 1580 ± 30 CE. A regional ocean hindcast links SCFR to enhanc…