Early-middle Holocene ecological change and its influence on human subsistence strategies in the Luoyang Basin, north-central China

In north-central China, subsistence practices transitioned from hunting and gathering to millet-based agriculture between the early and middle Holocene. To better understand how ancient environmental changes influenced this shift in subsistence strategies and human activities at regional to local levels, we conducted palynological and lithologic analyses on radiocarbon-dated sediment cores from the Luoyang Basin, western Henan Province. Our palynological results suggest that vegetation shifted from broad-leaved deciduous forest (9230-8850 cal yr BP) to steppe-meadow vegetation (8850-7550 cal yr BP), and then to steppe with sparse trees (7550-6920 cal yr BP). Lithologic analyses also indicate that the stabilization of the Luoyang Basin's floodplain after similar to 8370 cal yr BP might have attracted people to move into the basin, promoting the emergence of millet-based agriculture during the Peiligang culture period (8500-7000 cal yr BP). Once agricultural practices emerged, the climatic optimum after similar to 7550 cal yr BP likely facilitated the expansion of the Yangshao culture (7000-5000 cal yr BP) in north-central China. As agriculture intensified, pollen taxa related to human disturbance, such as Urtica, increased in abundance.