What are the biogeochemical consequences of heuweltjie formation?

This study was to determine whether the basal calcrete layer of heuweltjies derives its nutrients from local or exotic sources and also to estimate relative rates of deposition and an approximate age of the heuweltjie. By calculating deposition rates and by using data from Soderberg and Compton [1998] heuweltjies were found to be much older than previous research has indicated ~95 000 years old. ⁸⁷/⁸⁶Sr isotope ratios of on-mound and off-mound soils indicate that the majority of the nutrients are exotically derived. However, it is important to note that there are various different sources which could have contributed to the mound and that it could not be determined what sources had contributed in what proportions. It was determined through a simple mixing model that approximately 90% of the nutrients are derived from marine aerosol.

Grantor dc:publisher.institution

Department of Biological Sciences

Year dc:date.issued

2008

Author dc:creator

• Harington, Amy

Advisor dc:contributor.advisor

• Midgley, Jeremy J

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/25582

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/25582