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Over the past two decades, environmental studies in research on prehistoric China have been gaining popularity and importance. For Northwest China in particular, climate change, especially the so-called ~4.2k BP event has been seen as the main reason for an alleged collapse of Late Neolithic societies and a transition to pastoral-heavy economies and mobile lifeways. Yet, these explanatory models tend to rely on limited archaeological and environmental data and non-contemporaneous historical data, resulting in simplistic causal relationships between environmental changes and social response. This paper re-evaluates the Incipient Bronze Age in China's Northwestern region, discussing evidence for climate change and its exact dates, as well as textual and archaeological evidence. We argue that the old narratives perpetuating the image of a dichotomy between Steppe and Sown are inaccurate, while large-scale models of region-wide subsistence change in response to climate cooling tend to disregard local developments and group-specific responses as well as chronological issues. Focusing on the Xindian and Siwa archaeological phenomena, this paper provides a view into sub-regional responses to this climate event, warning against simplistic broad-brush reconstructions and calling for both a return to archaeological fundamentals and large-scale intensive fieldwork and interdisciplinary studies involving archaeologists, paleobotanists, zooarchaeologists, isotope specialists, and climate scientists. [ABSTRACT FROM AUTHOR]

Quantifying the relative influences of anthropogenic activities and climate change on soil erosion and deposition during the Holocene, when both forces have been interacting is a complex problem. Analysis of long-term patterns in soil erosion and lake deposition in a basin can provide the basis for untangling the complexities of climate and anthropogenic forcings. In this paper, sedimentary sequences from Xingyun Lake are compared with simulated soil erosion rates in the basin to explore the relationship between river basin soil erosion and lake deposition during the Holocene in Yunnan, China. Modern soil erosion rates are calculated using RUSLE, while Holocene soil erosion rates are estimated using modern rates with reconstructed precipitation and vegetation cover sequences. Through this investigation, we found the following results. First, Holocene vegetation in the lake basin was mainly affected by climate change, and the vegetation experienced the same pattern of changes as the climate. Soil erosion and lake deposition rates, along with changes to vegetation cover, were synchronous with precipitation trends during the Holocene. Second, soil erosion and lake deposition have been exacerbated by human activities, such as deforestation and land reclamation in the Xingyun Lake basin. Finally, this study provides new insights into the effects by anthropogenic impacts and climate forcing on the processes of soil erosion and lake deposition on the millennium scale. [ABSTRACT FROM AUTHOR]

A comprehensive and integrative view of East Asian monsoon evolution during the Holocene is still under debate, and additional high-resolution proxy records from climatically sensitive locations are requisite to solve this complex issue. In this paper, we present three well-dated mud/peat cores from a paleo-pingo depression in the Sanjiang Plain, a climatically sensitive region to monsoon variation, to reveal the paleoenvironmental history of the wetland and discuss the regional impacts from monsoon evolution. A paleolake developed in the study area before 5.5 ka BP, and a peatland initiated thereafter consequent upon the gradual shrinking of the paleolake. This transition lasted until 4.5 ka BP, when the paleolake changed entirely to a wetland. Considering the prevalent monsoon climate in the Sanjiang Plain, we suggest that the lake-to-wetland transition from 5.5 to 4.5 ka BP indicates a rapid decline of the East Asian summer monsoon in addition to autogenic basin infilling processes. Such a remarkable monsoon weakening event has been documented across northern China, and we associate this with ocean–atmosphere interactions throughout low-latitude regions. [ABSTRACT FROM AUTHOR]

Based on compilation of a large number of archaeological and palaeosol 14C-ages, the Summed Probability Method is used to reconstruct population history and climatic patterns on the Chinese Loess Plateau during the period 8.5–3.5 cal. ka BP. During this period, the population experienced two major expansion periods and several climatic fluctuations. The first population expansion began at around 7.8 cal. ka BP, and the second at around 5.8 cal. ka BP. During the first period, although already in combination with cultivation of broomcorn millet the population growth was supported mainly by hunting and gathering. With the switch from broomcorn millet to foxtail millet, plant cultivation became the major factor promoting a second population increase. In this paper, we demonstrate that, initially, suitable climate and agriculture both can facilitate population growth and climate events had a significant influence on demographic fluctuations. However, when reaching the threshold of land capacity, population became increasingly more sensitive towards climate fluctuations. [ABSTRACT FROM AUTHOR]

The vast Dongting Lake in the middle Yangtze River basin, China, was occupied by Chinese Neolithic settlements starting 10 000 years ago, and rice cultivation there is probably the earliest in the world. The numerous Neolithic settlements identified by previous archaeological surveys represent the five major Neolithic cultural stages, i.e. the Pengtoushan (9000–7900 cal. yr BP), Zaoshixiaceng (7900–6800 cal. yr BP), Daxi (6800–5500 cal. yr BP), Qujialing (5500–5000 cal. yr BP), and Shijiahe (5000–4000 cal. yr BP). Using sedimentological and geoarchaeological approaches, this paper analyses the drivers of basin-scale settlement relocation in relation to lake-level fluctuations and monsoon climate variations in the Holocene. The relocation of Neolithic sites around the lake shoreline and on the adjacent floodplain, together with radiocarbon-dated stratigraphy, clearly indicates that the shape of the lake basin was an incised and elongated valley occupied by a lake in the early Holocene, which became a broader and shallower depression in the mid to late Holocene. The established lowest habitable base of the settlements positioned on the lake shore assists reconstruction of the change in lake level from 22 m at 9000 cal. yr BP to 26 m at 5500–4000 cal. yr BP, although higher and lower lake levels occurred during the intervening cultural stages. The pollen spectra reveal a warming trend throughout the Holocene with at least four major temperature cycles, driven by monsoon variations between temperate- and warm-humid conditions. In the early Holocene the climate changed from cool-dry to warm-humid, and this played a key role in developing the earliest Pengtoushan culture in the region. Subsequent climate fluctuations fit well with the advance and retreat of the lake shore, also coevally with Neolithic site movements in the lake region. In this study we show how geoarchaeological evidence can be used in environmental reconstruction during the Holocene. [ABSTRACT FROM AUTHOR]

Abstract: A total of 237 surface soil pollen samples were collected from less disturbed zonal communities, and a new surface pollen data set has been established in northern China. Pollen-climate parameter transfer functions using weighted-averaging regression and calibration partial least squares (WA-PLS) model as a tool to reconstruct past climate changes from pollen data, were tested with this new surface pollen data set. The results of cross validation showed that the method worked very well with precipitation (R = 0.94, R2 jack = 0.89, RMSEPjack = 69 mm, the safe dynamic range of the reconstruction was 40 mm~800 mm) and worked well with temperature (Tann: R = 0.84, R2 jack = 0.71, RMSEPjack = 2.0°C, the safe dynamic range of the reconstruction was -4°C~13°C; MTwa: R = 0.79, R2 jack = 0.63, RMSEPjack = 2.5°C, and the safe dynamic range of the reconstruction was 8°C~26°C), indicating that the surface pollen data set and WA-PLS reconstruction technique in this paper have strong potential for palaeoclimatic reconstruction. [ABSTRACT FROM AUTHOR]

This paper reviews recently published literature, most of which was published in Chinese, and searches for regional patterns of Holocene changes useful in depicting global patterns. The Holocene in the Xinjiang region can be divided into three stages: a warming and dry early stage (from 11 ∼ 10 to 8 ∼ 7 ka BP), a warm and wet middle stage (from 8 ∼ 7 to 4.5 ∼ 3 ka BP) and a fluctuating cool and dry late stage (since 4.5 ∼ 3 ka BP). The Holocene in the northern Tibetan Plateau can also be divided into three stages: a warming and wet stage (from 10.5 ∼ 10 to 5 ∼ 4 ka BP), followed by a variable drying and probably warm stage (5 ∼ 4 to 3 ka BP) and ending with a cool and dry stage (since 3 ka BP). In the Inner Mongolian Plateau, the early Holocene (from 10.5 ∼ 9.5 to 8 ∼ 7.5 ka BP) was warming and dry, and a warm and wet climate occurred from 7.5 to 3.5, during which the best time was 6.3–3.8 ka BP; the climate has been variably drying and probably cooling since 3.5 ka BP. In the northwestern part of the Loess Plateau, several Holocene palaeosols have been identified (10–9, 7.5–5, 4–3 and 2.7–2 ka BP) with the 7.5–5 ka BP palaeosol being most strongly expressed. The best-developed palaeosol-equivalent in major valleys is a swamp-wetland facies deposited between 8885 and 3805 14C yr BP under an extremely wet regime. The climate has fluctuated significantly at least three times around a dry and probably cool regime after the swamp-wetland facies-depositional period. Our summary shows that the Holocene Climatic Optimum occurred nearly contemporaneously (8–5 ka BP) at all sites in the Xinjiang region, in the Inner Mongolian Plateau and in the northwestern part of the Loess Plateau. A warming and wet early Holocene (10–8 ka BP) in the northern Tibetan Plateau is most likely related to high effective soil moisture resulting from snow and ice melting. We propose here that the middle Holocene Climatic Optimum (8–5 ka BP) in arid to semi-arid China was primarily a delayed response of the low latitude oceans to high latitude peak insolation (9–8 ka BP). [ABSTRACT FROM AUTHOR]

The focus of this paper is on the reconstruction of the mid-Holocene climatic changes based on the pollen records contained in a 6.2 m thick section in the southern part of the Tengger Desert, northwestern China. To understand the modern analogues of the mid-Holocene changes, modern pollen spectra across different vegetation zones from the Qilian Mountains to the lowland Tengger Desert were studied first. Four pollen combinations were identified, corresponding to four different modern ecological environments: (1) a Picea-Artemisia combination in a spruce forest and its vicinity; (2) an Artemisia-Chenopodiaceae-Gramineae-Salix combination in a mixture belt of montane grassland and poplar woodland; (3) a Chenopodiaceae-Artemisia-Nitraria combination in a desert steppe belt; and (4) an Elaeagnus-Artemisia-Chenopodiaceae-Nitraria combination in a desert riparian forest. Our study also shows that a relatively low percentage of Picea pollen (30–10%) seems to be associated with water transportation (alluvial deposits) and a very low percentage of Picea pollen (10–5%) appears to be related to long-distance air transportation. With references to the modern relationships between pollen assemblages and associated bioclimates, the pollen sequence covering the period between 8500 and 3000 cal. BP was used to infer the climatic change history. The results show that a warmer and drier climate dominated between 8500 and 7950 cal. BP. Subsequent decreases in Artemisia and warm desert forbs/shrubs taxa and contemporaneous fluctuating increases in montane coniferous and aquatics elements from 7950 to 7400 cal. BP reflect a fluctuating increase in humidity and/or a fluctuating decrease in temperature. The following period from 7400 to 5650 cal. BP was generally warm with the Holocene Climate Optimum occurring between 7400 and 6500 cal. BP. A remarkably cool spell followed between 6500 and 6300 cal. BP that was then succeeded by a warmer and more humid period between 6300 and 5650 cal. BP. The period between 5650 and 4450 cal. BP was characterized by drastic oscillations in climatic conditions with three humid and probably cold spells intervened by three relatively dry and warm spells. The period between 4450 and 3500 cal. BP was cold and humid, followed by a wet spell as indicated by a very high percentage of Typha pollen. [ABSTRACT FROM AUTHOR]