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Title: Paleoecological evidence for late Holocene aridification from the Taolambiby subfossil site of southwestern Madagascar
Taolambiby, a key subfossil site in southwestern Madagascar, has yielded many bones of extinct large lemurs and associated fauna in excavations spanning more than a century. In 2004 our group collected a 4.4 m sediment profile from deposits near prior excavations. Our aim was to use sedimentological and palynological inferences to examine the interaction between climate change and human activities, in order to better understand how each may have contributed to local extirpations. The basal age of this profile was ca. 3500 cal yr BP. Lithology of the excavated and cored material showed many changes in sediment regime, reflecting the variable natureof the basin’s hydrology. After ca. 1500 cal yr BP, the record shows successive drying of the site and subsequent erosion and redeposition. After this time, pollen and spores were not preserved but charcoal particles continued to provide a record of local and regional fires up to the present. Between 340 and 250 cm below surface, pollen was well-preserved, showing evidence for a mixture of mesic and xeric vegetation, including many trees, shrubs, forbs, and ferns, most still found in the adjacent Bezà Mahafaly Special Reserve. This pollen record, spanning the period from ca. 3000 - 1500 cal yr BP, shows evidence for increased wetness at the beginning of the period and subsequent aridification. Coprophilous fungus spores (Sporormiella) are high during this same interval, suggesting the local presence of abundant megafauna, but decline with increasing aridification.  more » « less
Award ID(s):
1750598
NSF-PAR ID:
10317010
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Malagasy nature
Volume:
15
ISSN:
2661-9032
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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