The Late Quaternary Aeolian Deposits in the Subtropical Bose–Bubing Basins, Southern China

Aeolian deposits are globally recognized as sensitive recorders of Quaternary climate and environmental change, exemplified by the continuous loess sequences of the Chinese Loess Plateau in northern China, which document paleoclimatic and paleoenvironmental evolution since the Miocene. However, such deposits have rarely been confirmed in low-latitude inland regions of southern China. Here we present systematic evidence of aeolian deposition in a low-latitude environment, namely at the Xinlipoding (XLPD) Paleolithic site, situated between the Bose and Bubing Basins in Guangxi, southern China. Using optically stimulated luminescence (OSL), geochemical, and grain-size analyses, we investigate 100 cm thick yellow-brown sandy loam exposed on the hillside of the Bubing Basin. OSL dating constrains its accumulation between 25.3 ± 1.5 ka and 2.7 ± 0.1 ka, spanning the Last Glacial Maximum (LGM) to the late Holocene. Geochemical signatures indicate that the sediments were primarily derived from a nearby terrace in the Bose and Bubing Basins. Grain-size end-member modeling further reveals a mixed alluvial-aeolian origin, comprising both windblown and reworked loess. These findings demonstrate that aeolian dust deposition persisted even in the humid subtropical low-latitude regions of China, recording continuous dust input across glacial–interglacial cycles. The XLPD section thus provides a valuable framework for reconstructing late quaternary environmental change and extends the spatial reach of global aeolian deposition into previously underrecognized regions. Importantly, it also offers a crucial paleoenvironmental context for human occupation in the Bubing Basin from the LGM through the late Holocene.