Biostratigraphic and palaeoenvironmental applications of testate amoebae

Testate amoebae (also referred to as rhizopods, thecamoebians and arcellace ans) are single-celled organisms in which the cytoplasm is enclosed within an external shell (the test). They live in a wide range of terrestrial and aquatic habitats, including wet soils, lakes and saltmarshes, and fossil te sts have been recovered from sediments from all these environments. This pa per reviews existing and recently developed applications of testate amoebae analysis to biostratigraphic description of Quaternary sediments and palae oenvironmental reconstruction. Advances in testate amoebae analysis are dis cussed for three key areas of Quaternary research and the potential for the further exploration and use of the technique is emphasised. These areas ar e: (1) Peatlands and palaeoclimates Testate amoebae have been used as a new method of reconstructing palaeoclimates from ombrotrophic peats; (2) lake sediments: Testate amoebae respond to acidity levels in lakes but they may also be useful as indicators of pollution and temperature; (3) saltmarshes and sea-level change: Testate amoebae can now be added to diatoms and foram inifera as potential indicators of sea-level change. The paper concludes wi th an examination of future developments in testate amoebae research and hi ghlights the need for further work to explore their full range of occurrenc e in Quaternary sediments. (C) 2001 Elsevier Science Ltd. All rights reserv ed.