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Discriminating the provenance of fine-grained sediments is crucial for reconstructing paleogeography, sedimentary processes, and paleoclimate. In this paper, we investigate the South Bohai Coast to better understand source-to-sink systems in East Asia. This region is influenced by both distant sources such as the large-scale Yellow River and small local river sources flowing from the Luzhong Mountain area. Two Holocene sedimentary cores, dated using optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) 14C chronology, were used to investigate the provenance of the fine-grained sediments over the last 7 kyrs. Clay mineralogy and relevant non-linear modeling were employed for provenance discrimination. The results show that the fine-grained sediments along the South Bohai Coast were mainly derived from the Yellow River during the periods of 7.0–5.4 ka and 4.5–2.6 ka, respectively, while the input from the Luzhong Mountain-derived rivers was greater during 5.4–4.5 ka and 2.6–0.2 ka, respectively. Fluvial activities and marine-terrestrial interaction driven by climate factors such as East Asian winter monsoon, temperature, and precipitation in river basins, dominantly influenced the provenance of fine-grained sediments from 7.0 to 2.6 ka. Anthropogenic impact on provenance increased after 2.6 ka. The chronology of the two cores showed extremely rapid sedimentation rate transitions at 5.2 ka and 1.5 ka, respectively, very likely attributed to anthropogenic-induced rapid progradation. Our study provides a model for better understanding the paleoenvironmental and paleogeographic evolution of a coastal area where multiple sources exist. • Anthropogenically high sedimentation rate in the South Bohai Coast in late Holocene. • Provenance discrimination of the fine-grained sediments in the South Bohai Coast since the mid-Holocene. • The major source of the fine-grained sediments in the South Bohai Coast changed episodically. [ABSTRACT FROM AUTHOR]

In this paper, stable isotope (δ 13C, δ 18O) analyses of five equid species from the Linxia Basin, northwestern China, were conducted to investigate dietary niche turnover during a critical Pliocene-Pleistocene phase in the evolution of Old World Equidae. In the Early Pliocene Shilidun fauna, Proboscidipparion pater is inferred to have mainly fed on C 3 grasses in open grasslands as indicated by their relatively high δ 13C values (−9.1 ± 0.4‰, five teeth, n = 61), whereas Cremohipparion licenti and Sivalhippus platyodus were possibly mixed feeders inhabiting woodlands and grasslands because of their comparatively low δ 13C values (−10.8 ± 0.6‰, seven teeth, n = 36; −10.6 ± 0.6‰, nine teeth, n = 35). Inhabiting the same environments, both C. licenti and S. platyodus went extinct, possibly, because climatic changes led to a decline in woodlands resulting in greater competition. In the Early Pleistocene Longdan fauna, Proboscidipparion sinense had higher δ 13C values (−9.1 ± 0.5‰, four teeth, n = 23) than coexisting Equus eisenmannae (−10.2 ± 0.5‰, eight teeth, n = 57), implying that P. sinense had a stronger grazing preference compared to E. eisenmannae. Ecomorphological analyses (body size, tooth crown height, and enamel surface complexity) reveal that P. pater and P. sinense had dental characteristics consistent with a strong grazing preference. Therefore, P. pater might have been preadapted to open grasslands during the warm and humid Early Pliocene, which helped its descendent P. sinense persist into the Pleistocene. The results of this study reveal distinct dietary niches for these equids for the first time and shed light on some aspects of the evolutionary history of Equidae in East Asia. • Dietary niche partitioning of five fossil equids were reconstructed through stable isotopes in East Asia for the first time. • Preadaption to open grasslands of Proboscidipparion pater during the Pliocene helped this genus persist into Pleistocene. • Cremohipparion licenti and Sivalhippus platyodus went extinct due to interspecific competition on habitats in Pliocene. • Early Pleistocene hipparion Proboscidipparion sinense occupied more open environments than coexisting Equus eisenmannae. [ABSTRACT FROM AUTHOR]

Yue et al. (2021) have proposed a model of two Upper Palaeolithic industries in Northeast China called the "Initial Microblade Industry" and the "Northern Microblade Industry", with the latter originating from the former, and its spread to the neighbouring regions of Northeast Asia. We have found several inconsistencies in their factual data and methodology, and therefore the conclusions reached by Yue et al. (2021) cannot be accepted at face value. Using the most reliable evidence, the oldest true microblade assemblages are known from the Korean Peninsula. We suggest that this region is the more probable centre of diffusion of microblade technology in mainland Northeast Asia, including China and the Russian Far East. • Yue et al. (2021) published paper on microblades in Northeast China. • They have several inconsistencies in factual data and methodology. • We address the most debatable issues related to Yue et al. (2021). • The earliest true microblades originated in Korea and not in Northeast China. [ABSTRACT FROM AUTHOR]