Abstract:
Assesses the feasibility of using wood charcoal from archaeological sites as a palaeoclimatic indicator. Three techniques are described: charcoal identification from Xylem Anatomy, Ecologically Diagnostic Xylem Analysis and stable carbon isotope analysis on wood charcoal. Charcoal identification shows that the most common woody species at Elands Bay today are also evident in the archaeological record over the last 4000 years, indicating a relatively stable plant community composition. This study demonstrates that the wood anatomy of Rhus is not simply related to climatic factors, necessitating the employment of a wide range of statistical analytical techniques to identify climatic signals. In contrast, the anatomy of Diospyros shows strong correlations with temperature. Factor analysis of anatomical parameters of charcoal from Elands Bay archaeological sites indicates that there have been temperature changes over the last 4000 years. Stable carbon isotope ratios of plants have been found to be a useful indicator of water use efficiency; plants in drier habitats exhibit more positive values than their more mesic relatives. The results of an isotopic analysis on modern wood charcoal show that 13C/12C ratios can be related to temperature and rainfall. Indications are that wood charcoal does carry a climatic signal. A larger sample from more areas may give more dependable results.
