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Abstract: The northeastern Qinghai-Tibetan Plateau (QTP) lies at the convergence of the Asian winter and summer monsoons and westerlies, making it an ideal place for studying the effects of climatic change, owing to its fragile ecological environment and unique geographical location. This paper reports on a multi-proxy analysis consisting of magnetic susceptibility, total organic carbon content (TOC), pollen, grain size, and geochemical parameters from the peat deposit in the Gonghe Basin to reconstruct the Holocene millennial-scale climatic variation. The results indicate that the climate tended to be warm and humid since 10.0 cal ka BP, but it deteriorated obviously (cold and dry) in 8.6–7.1 cal ka BP. The regional optimal warm and humid period was from 7.1–3.8 cal ka BP, although there were frequent climatic fluctuations during that time. Thereafter, the climate became cold and dry. 10 millennial-time-scale cold events were recorded, which were coincident with climatic records from deep sediments in the North Atlantic Ocean, ice cores, lakes, peat, and aeolian deposits in the QTP. In addition, we discovered that the southwestern monsoons forced by solar insolation in the Holocene have crucial effects on regional climatic change, and the millennial-scale cold fluctuations are possibly related to the thermohaline circulation (THC). [Copyright &y& Elsevier]

Abstract: Palaeoenvironmental and palaeoclimatic data indicate that during the mid-to-late Holocene eastern Australia became significantly drier and experienced more intense and more frequent droughts. These changes, driven by the re-emergence and intensification of the ENSO climate phenomena, have been argued to have had considerable impact on Aboriginal societies, although there is uncertainty as to the exact nature, timing and magnitude of this impact. This paper analyses changes in the utilisation of toxic Macrozamia (cycad) seeds at seven archaeological sites in eastern Australia, identifying an extremely close correlation between the intensity of seed use and two proxy ENSO datasets, and a weaker correlation with a third ENSO dataset. Given the ecological attributes and resource potential of these plants, it is argued that these correlations are best explained as an intensified exploitation of a lower-ranked resource in direct response to the increased subsistence risks and lower productivity created by ENSO-driven climatic conditions. It also suggests that by 3000 BP the intensification of the ENSO system was driving changes in human subsistence behaviour on a sufficient scale to have considerable impact on other aspects of the wider cultural systems. [Copyright &y& Elsevier]

• We review the state of research on human-environment interaction in Holocene China. • We demonstrate the benefits of a multidisciplinary, regionally focused approach. • We conclude datasets must be local and specific, and integrate data on multiple scales. • China is large, well-documented, and critical for understanding social-natural systems. This paper reviews recent archaeological research on human-environment interaction in the Holocene, taking continental China as its geographic focus. As China is large, geographically diverse, and exceptionally archaeologically and historically well-documented, research here provides critical insight into the functioning of social-natural systems. Based on a broad review of the field as well as recent advances and discoveries, the authors reflect on research themes including climate change and adaptive systems theory, spatial and temporal scale, anthropogenic environmental change, risk management and resilience, and integration of subdisciplines. These converge on three overarching conclusions. First, datasets relevant to climate change and ancient human-environment interaction must be as local and specific as possible, as the timing of environmental change differs locally, and the human response is highly dependent on local social and technological conditions. Second, the field still needs more robust theoretical frameworks for analyzing complex social-natural systems, and especially for integrating data on multiple scales. Third, for this work to contribute meaningfully to contemporary climate change research, effective communication of research findings to the public and to scientists in other disciplines should be incorporated into publication plans. [ABSTRACT FROM AUTHOR]