Abstract
A 68 cm thick outcrop of diatomaceous sediments at the head of Mar Chiquita Lagoon on the Argentine coast near Buenos Aires provides evidence of Holocene paleoenvironmental changes related to sea level changes and freshwater input to the lagoon system. Salinity tolerances of extant diatom taxa were used for the reconstruction and multivariate analytical techniques were applied to reduce subjective interpretations of the diatom percentage data.
The basal half of the record was deposited before 3000 years ago and fossil diatoms indicate generally freshwater conditions with one fluctuation in mesohalobous diatoms suggesting brackish water conditions at a depth of about 60 cm. Polyhalobous (marine) diatoms characterize the record after 3000 years ago and large numbers of epiphytic diatoms indicate salt marsh environments with episodic seawater fluctuations to supratidal levels. Freshwater diatoms returned at the top of the outcrop, presumably as a result of the restriction of the historic marine inlet to the lagoon and the effects of freshwater inflow to the basin.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Fontes, J. Ch., F. Gasse, Y. Callot, J. C. Plaziat, P. Carbonel, P. A. Dupeuble & I. Kaczmarska, 1985. Freshwater to marine like environments from Holocene lakes in northern Sahara. Nature 317: 608–610.
Hendey, N. I., 1964. An introductory account of the smaller algae of the British coastal waters. Part V. Bacillariophyceae (Diatoms). Fish. Invest. Series IV. Her Magesty's Stationery Office, London, 315 pp.
Hustedt, F., 1957. Die diatomeen des flussytems der weser im Gebiet der Hansestadt Bremen. Abh. Naturwiss. Verein. Bremen XXXIV, 34: 173–440.
Kolbe, R. W., 1927. Zur Okologie, morphologie und systematik der brackwasser diatomeen. Pflanzenforschung 7: 1–145.
Schnack, E. J., J. L. Fasano & F. I. Isla, 1982. The evolution of Mar Chiquita lagoon coast, Buenos Aires province, Argentina. In Colquhoun, D. J. (ed.). Holocene sea level fluctuations: magnitude and causes. Univ. S. Carolina, Columbia, S.C.: 143–155.
Vos, P. C. & H. de Wolf, 1988. Methodological aspects of paleoecological diatom research in coastal areas of the Netherlands. Geol. Mijnbouw 67: 31–40.
Wilkinson, L, 1986. SYSTAT: the system for statistics. Evanston, IL: SYSTAT, INC.
Author information
Authors and Affiliations
Additional information
This is the second in a series of papers published in this issue on “Paleolimnology in Southern South America”. Dr. C. A. Fernández served as guest editor for these papers.
Rights and permissions
About this article
Cite this article
Espinosa, M.A. Diatom paleoecology of the Mar Chiquita lagoon delta, Argentina. J Paleolimnol 10, 17–23 (1994). https://doi.org/10.1007/BF00683142
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00683142