Tufa stromatolite ecosystems on the South African south coast
Following the first description of living marine stromatolites along the South African east coast, new investigations along the south coast have revealed the occurrence of extensive fields of actively calcifying stromatolites. These stromatolites have been recorded at regular distances along a 200-k...
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Published in | South African Journal of Science Vol. 110; no. 9-10; p. 1 |
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Main Authors | , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Pretoria
African Online Scientific Information Systems (Pty) Ltd t/a AOSIS
01.09.2014
Academy of Science of South Africa |
Subjects | |
Online Access | Get full text |
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Summary: | Following the first description of living marine stromatolites along the South African east coast, new investigations along the south coast have revealed the occurrence of extensive fields of actively calcifying stromatolites. These stromatolites have been recorded at regular distances along a 200-km stretch of coastline, from Cape Recife in the east to the Storms River mouth in the west, with the highest density found between Schoenmakerskop and the Maitland River mouth. All active stromatolites are associated with freshwater seepage streams flowing from the dune cordon, which form rimstone dams and other accretions capable of retaining water in the supratidal platform. Resulting pools can reach a maximum depth of about 1 m and constitute a unique ecosystem in which freshwater and marine organisms alternate their dominance in response to vertical mixing and the balance between freshwater versus marine inflow. Although, the factors controlling stromatolite growth are yet to be determined, nitrogen appears to be supplied mainly via the dune seeps. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0038-2353 1996-7489 |
DOI: | 10.1590/sajs.2014/20140011 |