δ13C and δ15N from 14C-AMS dated cereal grains reveal agricultural practices during 4300-2000 BC at Arslantepe (Turkey)

Stable isotope values of cereals show temporal trends in water supplies and manure application. Irrigation was provided to barley crops from 4300 to 3100 BC during the rise of centralised political organisation at the site. Different locations of barley fields are suggested from 3100 to 2000 BC when domestic economies are attested. In addition, the marked increase of barley δ15N values from 3350 to 3000 BC reveals manuring and/or cultivation in pasturelands due to the deposition of animal urea and dung. Wheat could have been grown close to the site, where irrigation water from natural springs was available. Emmer and wheat seem to have been cultivated in the same areas or directly in the same fields. During 3000-2500 BC intercropping cultivation is inferred by low δ15N values. The evidence of mixture crops confirms the increase of pasturelands during herders' occupations and the concentration of crop fields possibly around the site.