Archaeobotanical evidence for the interrelationship of agricultural decision-making and climate change in the ancient Near East

Abstract

The potential of archaeobotanical data for investigation of environmental change was examined with a multi-site approach to tracking changes in crop husbandry. Archaeobotanical data from 138 sites in the Levant, Syria and northern Mesopotamia were mapped with geographical information system (GIS) software. The presence, proportions and ubiquities of the main Near Eastern crop plants throughout a sequence spanning from the Early Bronze Age to the Iron Age (5000–2500 cal. BP) were analyzed for developmental patterns related to the palaeoclimatic history of the region, modeled climate parameter, anthropological facts and the bioclimatic properties of the crop species. Although there are considerable methodological problems, the overall patterns emerging from this large database demonstrate how agricultural decision-making was influenced by climate change in the past. While a relatively favorable degree of available moisture can be recognized in the crop assemblages of Early Bronze Age sites, with the cultivation of numerous crops with comparatively high water-requirements, the impact of the 4200 BP event, with an increased aridity after 4000 BP latest, is reflected strongly in the reduction or absence of drought-susceptible crop species in the Middle Bronze Age. The general pattern of crop proportions and ubiquities during the Late Bronze Age implies a further, although slight, increase in arid conditions, particularly in northern Syria. However this is much less marked than that for the Early to Middle Bronze Age transition. Regional variation is large for some crops, and an increase in arid conditions is not indicated by the patterns of crop production for the southern Levant. The patterns during the Iron Age suggest a slightly better water availability.