C-13 AND O-18 OF WOOD FROM THE ROMAN SIEGE RAMPART IN MASADA, ISRAEL (AD 70-73) - EVIDENCE FOR A LESS ARID CLIMATE FOR THE REGION

The isotopic ratios C-13/C-12 and O-18/O-16 of cellulose from tamarix trees which were used by the Roman army as a groundwork of the siege-r ampart of Masada (AD 70-73) were compared with ratios measured in pres ent-day tamarix trees growing in the Masada region and in central Isra el. The ancient tamarix cellulose is depleted in both C-13 and O-18 co mpared to cellulose from trees growing in the Masada region today. Sim ilar trends were observed on comparing modern tamarix trees growing in the Negev Desert with those growing in the temperate climate of centr al Israel. Considering the factors that can contribute to the observed changes in isotopic composition, we conclude that the ancient trees e njoyed less arid environmental conditions during their growth compared to contemporary trees in this desert region. This report demonstrates the potential in using combined O-18 and C-13 analyses of archeologic al plant material as independent indication of regional climatic chang e in desert areas (where conventional isotopic analyses, such as in tr ee rings, are impractical).