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This paper presents new field observations that assist in further defining the extent of Last Permafrost Maximum (LPM) permafrost and frozen ground in north China. In that respect, this region is specific by its arid environment and continental position. Bedrock exposures and sand and gravel pits were examined along a south-north transect from southern Ordos as far as the vicinity of Dongsheng District, Ordos City on the Ordos Plateau (North China). Attention focussed upon the recognition of sand-wedge remains and possible cryoturbations. Two types of wedge structures were recognized: type A wedges extend to depths in excess of 3.0 m and are thought to have formed under conditions of continuous permafrost. Type B wedges are restricted to the upper 1.5 m and are thought to reflect discontinuous permafrost and/or deep seasonal frost. OSL dating of wedge infills indicates that type A wedges formed between 23–19 ka and younger type B wedges formed until the early Holocene. It is now possible to delineate a more exact position of the boundary between continuous permafrost and discontinuous permafrost and/or deep seasonal frost on the Ordos Plateau during the LPM. This boundaries occur between Dongsheng and Jinbian at 37°-39°N.

During the Late Glacial, hunter-gatherers began using ceramic cooking containers in three separate geographic regions of East Asia: China, Japan and in the Russian Far East. While recent research has clarified the use of early pottery in Japan, very little is known about what led to the emergence of pottery in the other two areas, including the likely environmental, economic or cultural drivers. In this paper we focus on a series of key sites along the Amur River in the Russian Far East, where early pottery has been recovered from securely-dated contexts that span ca. 16,200 to 10,200 years ago (cal BP). Interpreting how these ceramic vessels were used has been difficult because the region’s acidic soils make palaeo-economic reconstructions challenging. To address this gap in knowledge we undertook lipid residue analysis of 28 pot sherds from the sites of Khummi, Gasya, and Goncharka 1 on the Lower Amur River, and the Gromatukha site on the Middle Amur. Our results indicate that pottery was employed to process aquatic oils at sites on the Lower Amur, a pattern of use that aligns closely with studies conducted in Japan, and suggests that fishing – probably of salmonids and freshwater fish – was becoming increasingly important during this period. In contrast, the results from the Middle Amur show a significant contribution of lipids from ruminant animals, indicating that these vessels were being used in different ways. Interestingly, these regional differences in pottery use also map onto contrasting manufacturing techniques, with vessels from the Middle and from the Lower Amur forming distinct pottery-making traditions. These combined insights appear to indicate a greater degree of variability in the development and use of early pottery in East Asia than has hitherto been indicated.

China is a key area of early human settlement in East Asia, with numerous Paleolithic localities indicating an early Pleistocene presence of hominins in northern and southern China. Considerable research has been devoted to determining possible migration routes for hominins linking the two areas. In this paper, we report the discovery of several loess-covered Paleolithic sites in the Hanzhong and Ankang Basins along the Hanjiang River in the southern piedmont of the Qinling Mountains (QLM) in central China. A chronology is developed for these sections using a combination of detailed optically stimulated luminescence dating, magnetostratigraphic analyses, and pedostratigraphic correlation with the well-dated loess–paleosol sequence of the central Chinese Loess Plateau. The results indicate that the age of the oldest lithic assemblage at the Longgangsi locality 3 Paleolithic site in Hanzhong Basin is ∼1.20 Ma, thus making this locality as one of the oldest sites in central China. Our work also indicates that hominins occupied the Hanjiang valley at several times: ∼1.2, 0.9, ∼0.6, and ∼0.1 Ma. We propose that the Hanjiang River Valley was a probable hominin routeway through the QLM because many sites corresponding to these different phases were also discovered to the north of the QLM. Future study on the Hanjiang River Valley is important for verifying the hypothesis of an early human migration route between southern and northern China.

Fossil pollen, as a direct proxy record of past vegetation, and indirect proxy record of past climate, plays an essential role in revealing and reconstructing past vegetation and climate. However, relationships between pollen, vegetation and climate are not linear, hence quantitative reconstructions of past vegetation and climate based on pollen records are not straightforward, and results may be highly contradictory and difficult to interpret. One of the main causes of discrepancies between results has been the lack of comprehensive and systematical studies on modern pollen dispersal and deposition processes, particularly on the quantification of these processes. Based on empirical studies performed in China over the last 30 years, this paper provides the state-of-the-art of the understanding of pollen dispersal and deposition processes in China and the remaining questions to be investigated. We show that major progress has been achieved in the study of modern pollen dispersal and deposition processes, and in the application of models of the pollen-vegetation-climate relationships for quantitative reconstruction of past vegetation and climate. However, several issues are not entirely solved or understood yet, such as how to quantify the reworking and re-deposition of pollen grains in quaternary alluvial sediments, the influence of pollen preservation on pollen assemblages, and human impact on vegetation. Even so, the progress made during the last decades makes it possible to achieve significantly more precise and informative reconstructions of past vegetation, land-use and climate in China than was possible earlier.

Speleothem records from NE Asia are essential to understand the spatial patterns of the Asian Summer Monsoon (ASM) variability. In this paper, we present a new high-resolution and chronologically well-resolved speleothem record from Liu-li (LL) cave, NE China, through δ18O, δ13C and Sr/Ca ratio characterizing a dynamic ASM history over the past 6680 years. The LL δ18O record shows a long-term trend to higher values, following the North Hemisphere summer insolation (NHSI), with the exception of the last 2 kyr characterized by a negative δ18O excursion. The ‘2-kyr shift’ is evident in NE Asia over the past 2 kyr, originally inferred from the speleothem δ18O negative excursion in South China, as well as in many other proxy records from East China, but it merely manifests a flat trend in most of the western East Asian Summer Monsoon (EASM) and Indian Summer Monsoon (ISM) regions, rather than a negative excursion. On multi-centennial to millennial timescales, the intensification of the Tsushima Warm Current (TWC) can amplify rainfall on both sides of the Japan Sea. A close comparison between the monsoon reconstruction and the cultural changes in NE Asia suggests contemporary climatic and cultural regime-shifts, implying an important role of the ASM weakening in the collapse of Neolithic and Early Bronze cultures in this region.

When this paper was first published, there were two errors in Figure 1(b). The “Tertiary red formation” was incorrectly labelled as “Tertiary red clay”, and “Cretaceous rocks” were incorrectly written as “Cenozoic rocks” in the figure legend. The correct artwork and legend are printed below: [Figure presented] Fig. 1. (b) Geological map of the study region where the upper Yellow River cut through the Jishishan Mountains forming the deep and narrow Jishixia Gorges.

The Tianchi Volcano, located on the border between China and North Korea, produced a massive Plinian eruption of Volcanic Explosivity Index (VEI) 7 around 1000 AD, which is referred to as “the Millennium eruption of Tianchi Volcano”. Until now, this volcanic eruption has not been well dated. In this paper, we report a series of new calibrated dates using wiggle-match dating from carbonized logs collected from fallout deposits on the southern and northern flanks of the Tianchi crater. Fifty AMS 14 C ages of tree rings from two logs were obtained for the Hengshan site, south of the Tianchi crater ( Fig. 1 ). These yielded a high-precision wiggle-match date of 921–941 cal AD (95.4%) for the Millennium eruption. Thirty-two AMS 14 C ages of tree rings of other two logs from the Dongfanghong site, north of Tianchi crater ( Fig. 1 ), produced an age range for the volcanic eruption from 921 to 942 cal AD (95.4%). A combined date for the four carbonized logs produced an age of 923–939 cal AD (95.4%) for the Millennium eruption. Moreover, an exact date of late autumn, 938 AD or early spring, 939 AD is suggested based on the impact of the Tianchi Volcano on global climate, especially East Asian climate, and the complete outermost rings of these four trees killed in the eruption.

The anthropogenic explanation for the increase in atmospheric methane concentration during the last 5000 years requires large CH4 emissions from human activities beginning early in the Bronze Age. This paper presents a compilation of 311 archeological sites in rice-growing regions of China. The number of new sites between 6000 and 4000 years ago increased almost ten-fold compared with those during previous millennia. This early spread of rice production across most of the area in China where irrigated rice is grown today supports the hypothesis that early farming caused the anomalous methane reversal.

Quantitative reconstruction of the climatic history of the Chinese Loess Plateau is important for understanding present and past environment and climate changes in the Northern Hemisphere. Here, we reconstructed mean annual temperature (MAT) and mean annual precipitation (MAP) trends during the last 136 ka based on the analysis of phytoliths from the Weinan loess section (34°24′N, 109°30′E) near the southern part of the Loess Plateau in northern China. The reconstructions have been carried out using a Chinese phytolith–climate calibration model based on weighted averaging partial least-squares regression. A series of cold and dry events, as indicated by the reconstructed MAT and MAP, are documented in the loess during the last glacial periods, which can be temporally correlated with the North Atlantic Heinrich events. Our MAT and MAP estimations show that the coldest and/or driest period occurred at the upper part of L2 unit (Late MIS 6), where MAT dropped to ca 4.4 °C and MAP to ca 100 mm. Two other prominent cold-dry periods occurred at lower Ll-5 (ca 77–62 ka) and L1-1 (ca 23–10.5 ka) where the MAT and MAP decreased to about 6.1–6.5 °C and 150–370 mm, respectively, ca 6.6–6.2 °C and 400–200 mm lower than today. However, the highest MAT (average 14.6 °C, max. 18.1 °C) and MAP (average 757 mm, max. 1000 mm) occurred at Sl interval (MIS 5). During the interstadial of L1-4–L1-2 (MIS 3) and during the Holocene warm-wet period, the MAT was about 1–2 °C and MAP 100–150 mm higher than today in the Weinan region. The well-dated MAT and MAP reconstructions from the Chinese Loess Plateau presented in this paper are the first quantitatively reconstructed proxy record of climatic changes at the glacial–interglacial timescale that is based on phytolith data. This study also reveals a causal link between climatic instability in the Atlantic Ocean and climate variability in the Chinese Loess Plateau.

Ten samples of slope-wash and colluvial deposits from a trench wall at Xiyangfang, Yanqing County, located in the northern margin fault zone of the Yanqing Basin, about 90 km northwest of Beijing, have been dated by both green light stimulated emission (GLSL) and infra-red stimulated emission (IRSL). Four of the samples were measured in both Adelaide (Riso equipment) and Beijing (Daybreak equipment), with essentially consistent results. The paper gives a comparison of equivalent dose values obtained by both GLSL and IRSL. The Xiyangfang trench wall presents four fault-scarp-collapsed wedges, showing a clear normal faulting pattern, which can be interpreted as a record of palaeo-earthquake events, covering a time period from about 100 ka to the modern. A return time of about 7000 yr is suggested for events at this site. An attempt is made to correlate the dating records with the local earthquake history of destructive earthquakes in the last 2000 yr.

Although molluscan faunas are the most widespread fossil remains in the Chinese loess. there have been very few attempts to use their potential for climatic reconstruction, or to develop cIimato-stratigraphic schemes. This paper reports assemblages of Mollusca from three sites in the North and South Central parts of the Loess Plateau, and evaluates the uses of molluscan faunas as climatic proxies in the S 1 palaeosol, the Malan Loess and S o palaeosol. The molluscan sequence is compared with the record obtained from pedological and magnetic techniques. The current study shows that major peaks in magnetic susceptibility, thought to be due to pedogenesis under warm, humid conditions, can be matched by levels of high molluscan abundance. The occurrence of a sharp molluscan peak within the Malan Loess, otherwise only indicated by a slight increase in magnetic susceptibility, is held to be due to the existence of a short-lived humid episode and demonstrates the sensitivity of Mollusca as indicators of relatively low magnitude climatic shifts not well indicated by other lines of evidence.