Oasis agricultural practices and seasonal transhumance pastoralism: adaptive strategies of Jiayi inhabitants to a hyper-arid environment, Turpan, Xinjiang

Climate of the Turpan Basin is hot and hyper-arid, a typical and ideal region for exploring the methods and strategies of ancient humans that had to adapt to marginal environmental conditions. Although stone artifacts have been previously discovered in the basin, most were collected at surface of sites. The strata of these artifacts was absent and their chronology was vague. The earliest archaeological findings with reliable dates from the basin emanated from Subeixi culture, 3200–1800 cal a BP, during the late Bronze and early Iron Ages. Plants recovered from Yanghai cemetery, a typical Subeixi cultural site, revealed that Yanghai community cultivated a small quantity of wheat, barley, and broomcorn millet. Livestock bones with related leather and fur products were commonly discovered in the cemetery. It has been speculated that local people were mainly engaged in livestock herding and concurrently developed small scale agriculture. Agropastoralism was adopted as a prominent pattern of economic production. A large number of wheat straws from late Subeixi culture were excavated from Shengjindian cemetery, indicating that scale of crop cultivation was expanded and agricultural production was intensified. In addition, remnants of fruits, like grapes and Chinese dates, appeared in the basin. Horticulture became an important component of the local economy. Despite archaeobotanical research at Yanghai, Shengjindian, and Yuergou sites, scientific recognition of a subsistence economy and adaptive strategies in reaction to the extreme arid climate of the basin practiced by prehistoric inhabitants, especially in the middle time period of the Subeixi culture, is lacking. New archaeological artifacts and discoveries are essential to fill informational gaps. In this present study, plant stems, leaves, seeds, fruits, and wood were first collected from Jiayi cemetery, a representative site of middle phase of Subeixi culture in Turpan and then systematically analyzed to determine patterns of botanical resource usage, subsistence economy, and adaptative strategies of local inhabitants. Results show that in total 28 plant species were preserved in Jiayi cemetery (2800−2300 cal a BP) and utilized for cereal, medicines, psychoactive agents, fibrous materials, decorative objects, and woodware-making tools, offering evidence of an abundant and varied collection of oasis-based plants and evidence of diverse utilization strategies and practices. Very few cereal crops, including naked barley (Hordeum vulgare var. celeste) and broomcorn millet (Panicum miliaceum), were recovered, indicating that dryland farming on a small scale was developed in the oases of the basin. In combination with results of multidisciplinary research, it proves that agropastoralism was practiced by Jiayi inhabitants, in which herding played a dominant role in their mixed subsistence economy. Wood composition results identified spruce (Picea sp.) and birch (Betula sp.) plants, which only grow in the higher altitudes of the Tianshan Mountains. Based on the geographical distribution and habitat niche of these two tree varieties and integration of archaeological findings, it is speculated that seasonal transhumance herding along with vertical vegetation zones of the Tianshan Mountains (Bogda Mountain) were simultaneously practiced by indigenous peoples of the Turpan Basin. Apart from this, camels in desert oases were herded year-round by few inhabitants and fed with broomcorn millet and its by-products after having been processed in the cold, late autumn and winter. Such animal management strategies contributed significantly to extending the survival space of oases, to sufficiently utilizing different plant resources under diverse upland and lowland climatic and environmental conditions, and to maximizing pastoral products and profits. Engaging in diversified subsistence patterns was an optimal and resilient strategy of early inhabitants of the Turpan Basin in order to better adapt to the extremely arid environment. It was a key driving force for promoting continuous development of the local prehistoric civilization.