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Title: Young death assemblages with limited time-averaging in rocky and Posidonia oceanica habitats in the Mediterranean Sea
Abstract Death assemblages (DAs) are increasingly recognized as a valuable source to reconstruct past ecological baselines, due to the accumulation of skeletal material of non-contemporaneous cohorts. We here quantify the age and time-averaging of DAs on shallow subtidal (5–25 m) rocky substrates and in meadows ofPosidonia oceanicain the eastern Mediterranean. We show that such DAs are very young – median ages 9–56 years – with limited time-averaging, one to two orders of magnitude less than on even nearby soft substrates. On rocky substrates, out-of-habitat transport is likely the main cause of loss of older shells. InPosidonia oceanicameadows, the root and rhizome system creates a dense structure – thematte– that quickly entangles and buries shells and limits the potential for bioturbation. Thematteis, however, a peculiar feature ofPosidonia oceanica, and age and time-averaging in meadows of other seagrass species may be different. The young age of DAs in these habitats requires a careful consideration of their appropriateness as baselines. The large difference in DA age between soft substrates, subject to numerous studies, and hard and seagrass substrates, rarely inspected with geochronological techniques, implies that DA dating is important for studies aiming at using DAs as baselines.  more » « less
Award ID(s):
1855381
PAR ID:
10469068
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
The Geological Society of London
Date Published:
Journal Name:
Geological Society, London, Special Publications
Volume:
529
Issue:
1
ISSN:
0305-8719
Page Range / eLocation ID:
41 to 48
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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