Southward retreat of the Keriya River drove human migration in the Taklimakan Desert during the late Holocene.

Rivers are the main water source for the oases, and rivers are essential for the wellbeing of the human inhabitants in the desert areas. The Keriya River flows through the south–central Taklimakan desert, the second largest mobile desert on Earth, in northwest China. The earliest archaeological site in the interior of the Taklimakan Desert together with the remains of several ancient cities are located along the Keriya River. Accurately dating the dry watercourses and ancient sites in this region is critical for understanding the changes in fluvial hydrology and their relationship with human activities in desert areas. Specially, the interactions between the hydrological processes of the Keriya River, and human activities are poorly understood due to the lack of a reliable chronology for this river associated with these ancient sites. In this study, we collected 18 samples from 12 fluvial and lacustrine sedimentary sequences for optically stimulated luminescence (OSL) dating, and we also, reviewed 23 dating results from previous studies to reconstruct the hydrological processes of the Keriya River since the early Holocene. Additionally, we also tested 28 14C dates from three ancient sites, combined with 33 14C dates from previous studies to reconstruct a timeline of human migration within the desert. The results show that the Keriya River retreated continuously from the early Holocene onward, due to the decreased supply of glacial meltwater and precipitation in the surrounding mountains, and this process triggered human migrations from north to south in the Taklimakan Desert after ∼3.5 ka. Overall, our findings reveal that variations in fluvial hydrological processes can trigger human migration in desert areas under the background of the global climate change. • We established the hydrological processes and human migration history along the Keriya River since the early Holocene. • The retreat of the river was synchronized with the human migration to the southern Taklimakan Desert. • The decreased supply of glacial meltwater and precipitation in the Kunlun Mountains triggered the river retreat. • The hydrological status and human settlements in the desert/arid area were sensitive to climate changes. [ABSTRACT FROM AUTHOR]