Agropastoral investment in plant cultivation at the Bronze Age site of Chap, Kyrgyzstan

Between the 3rd and 1st millennium BCE, domesticated crops and livestock originating from West and East Asia spread across the Eurasian landmass forming an interconnected farming system involving both indigenous and foreign resources. Interconnected networks established by Inner Asian mountainous communities likely facilitated the spread of these novel resources across an expansive geographic range. In this paper, we investigate cultivation strategies employed at the Bronze and Iron Age highland sites of Chap I and II in the Tien Shan Mountains, Kyrgyzstan. We conducted stable carbon ( δ 13 C) and nitrogen ( δ 15 N) isotope analyses to assess the water availability and soil nutrition conditions for cultivation of free-threshing wheat ( Triticum aestivum/durum/turgidum ) and 6-row naked ( Hordeum vulgare var. nudum ) and hulled ( Hordeum vulgare var. vulgare ) barley. We further analyzed stable isotope compositions of selected wild taxa and estimated the ecological habitats of all wild taxa recovered to contextualize the crop growing conditions. Results show that although wheat and barley were treated differently, both were cultivated with considerable care, with evidence of increased watering and manuring during the Iron Age. Situating our results in a broader regional context, our findings suggested that varied and localized cultivation strategies had been employed by pastoral communities across the Inner Asian mountains despite a continental-scale transmission of those crops.