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[Objective] This study examined the ecological and hydrological variability and regime shift during the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA) in the middle reaches of the Yangtze River. This region is climatically governed by the Asian monsoon, with increased precipitation in summer and decreased in winter. Our study helps deepen our understanding of the history of the regional ecological and hydrological changes and their connections to the monsoon climate. [Methods] Based on two high-resolution stalagmite (YX262 and YX275) δ13C records from Yongxing cave, Hubei province in the middle reaches of the Yangtze River, we reconstructed the history of the local paleoclimate and environment from 1 044-1 954 A.D. by creating a composite of the two records using the iscam program. [Results] The δ13C records show two completely different states during the MCA and LIA, with the lower δ13C values characterizing the MCA period, and the higher δ13 C values the LIA. During the transition from MCA to LIA, δ13C shows an abrupt change. This phenomenon indicates a regime shift from a strong to weak state for the vegetation respiration activity and precipitation variation. This variation is consistent with many stalagmite δ13C records in southwest China and the middle reaches of the Yangtze River. Here, our stalagmite δ13C record shows that the shift of the vegetation cover was rapid from the MCA to LIA. A Rampfit analysis shows that the stalagmite δ13C shift occurred between 1 434-1 460 A.D., lasting 26 years, which is more rapid and significantly longer than the stalagmite δ18O shift. This variation is attributed to both climate deterioration and human activity influences, leading to a reduction of vegetation cover during this period. On the one hand, the rapid transformation of the stalagmite δ13C record in Yongxing cave may be related to the great migration event in the early Ming Dynasty. A large number of migrants swarmed into Hubei province, inevitably leading to large-scale deforestation and land reclamation and changing the ecological environment of the surface soil vegetation. Those behaviors cause positive stalagmite δ13C. On the other hand, the Yongxing δ13C record is correlated with changes in the total solar radiation, intertropical convergence zone (ITCZ), temperature in eastern China, and El Nino-Southern Oscillation (ENSO) on the MCA and LIA event scales. During the MCA period, the total solar irradiance was larger, and the ITCZ was farther north, with a high frequency of El Nino states. However, during the LIA period, the total solar irradiance was relatively small, and the position of ITCZ was more southerly, in the low frequency period of El Nino states. This correlation indicates that the changes of hydrological circulation and vegetation cover in the middle reaches of the Yangtze River had a dynamic relationship with the regional and global climate change during the past millennium, and the impacts of human activities on surface vegetation may be related to the background of regional or global climate change. [Conclusions] By studying the δ13 C record of stalagmites in Yongxing cave in the past millennium, the eco-hydrological characteristics of MCA and LIA were found to be significantly different, which may be related to global climate change and human activities. The study not only clearly establishes the time boundary between MCA and LIA in the middle reaches of the Yangtze River, but also deepens our understanding of the characteristics and causes of eco-hydrological environment changes in the region during the two periods. [ABSTRACT FROM AUTHOR]

In the Basilicata region, located in southern Italy and known for hosting among the first occurrences of the Acheulean culture in southwestern Europe, the Lower Paleolithic site of Loreto at Venosa is located less than a kilometer from the emblematic site of Notarchirico and less than 25 km from Cimitero di Atella. The Loreto site has not been studied as thoroughly as the two other sites and, although geological investigations have been carried out in the Venosa basin, no direct numerical dating has ever been published for the three archaeological levels brought to light during the excavation campaigns. We present a multi-method geochronological approach combining ESR/U-series, ESR, and 40Ar/39Ar permitting to refine the age of the most ancient archaeological level (A) of the Loreto site. These data allow us to propose an MIS 13 age for this level, in accordance with previous hypotheses based on geological and paleontological data. We also propose a technical review of the lithic tools preserved in the collection of the National Archaeological Museum of Venosa to integrate Loreto in the evolution scheme of the European Acheulean techno-complex emergence and diffusion. [ABSTRACT FROM AUTHOR]