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This paper presents new data derived from pollen, starch and radiocarbon samples that were collected from six Aboriginal earth (oven) mounds and middens on the Calperum and Pike floodplains, Murray-Darling Basin (MDB), South Australia (SA). Analyses of these samples were undertaken in order to enhance our understanding about the Holocene lifeways of Aboriginal people living in this region. The results from these analyses, combined with published data about the mounds' contents, relevant ethno-historical information and climate data, allow us to infer that Aboriginal people adopted, in this region, an innovative food production system about 3800 years ago. Further, we argue that the timing of the change suggests this was in response to adverse El Niño Southern Oscillation (ENSO) related weather patterns and consequently fluctuations in both terrestrial and aquatic food resources. [ABSTRACT FROM AUTHOR]

The effects of climate change on long-term mercury (Hg) cycling are still not well understood, as climate changes are usually gradual and can only be assessed using high-resolution archives. Our study site (a small, lowland tectonic lake in Sulawesi, Indonesia) provides a unique opportunity to further understanding of Hg cycling in the Southeast Asian (SEA) tropics during the transition from the Pleistocene to the Holocene, a period of significant climate variability. We present a high-resolution record of Late Glacial and Holocene Hg deposition within the sediments of tropical Lake Lantoa, Sulawesi. Using amultiproxy framework (including pollen, charcoal, carbon:nitrogen ratio and highresolution geochemistry records) we investigate the response of Hg accumulation rates (HgAR) in sediments to shifts in climate between ~16,488 and 538 cal BP. This period encompasses the Bølling-Allerød (BA) warming, Younger Dryas (YD) cooling and Holocene warming events, providing new insights into the effects of global climatic transitions on HgAR in SEA sediments. The Pleistocene Termination had the highest HgAR and substantial variability (µ = 11.32, 5.38-33.91 µgm-2 yr-1), when drier conditions and high charcoal accumulation rates suggest that fire activity was the main source of Hg to the lake. The Holocene Transition was marked by a decrease in HgAR (µ = 8, 3.50-18.84 µgm-2 yr-1) as humid conditions precluded forest burning, followed by high HgAR (µ = 11.35, 3.30-158.32 µgm-2 yr-1) in the Early Holocene. Mercury accumulation rate in the Late Holocene (µ = 3.80, 1,67-43.65 µgm-2 yr-1) was the lowest in the Lake Lantoa record, marked by the lowest fire events and a stable catchment. An increase in carbon:nitrogen ratios during the Late Holocene, coupled with a decrease in HgAR, suggests that the establishment of lowland forest resulted in suppressed Hg erosion/leaching. Our results demonstrate that forest fires, vegetation change and volcanism are important drivers of Hg inputs to Lake Lantoa, a relationship which is strongly mediated by climate and lake-catchment dynamics. [ABSTRACT FROM AUTHOR]

Throughout the 4th to 6th Dynasties of the Old Kingdom (c. 2613–2181 BCE), liquid commodities were imported in ceramic combed jars made in workshops in the Byblos region, enabling proximal geographic identification of the original contents. Results of scientific, archaeometric, and archaeological research on a large corpus of jars found in elite tombs at Giza, now in the Museum of Fine Arts, Boston, reveal a complex story of the use and reuse of the jars and that very little remains of the original and even secondary contents. Rather, from the moment of production, the jars had a complex itinerary. At different times, jars were invested with diverse meanings that included their original use as a transport and product container, a symbol of royal power, an elite status symbol, and, more recently, a 20th-century museum artifact. It is argued that a number of jars were used more than once before final deposition in elite tombs, where they were provided as gifts to high officials and royal family members. The jars acquired the significance of prestige markers in the status framework of Egyptian elites, signifying proximity to royal grace and favor. As a result of ancient use and modern interventions, the original contents of the jars are difficult to discern, with wider implications for how to characterize the liquid commodities trade with the region. [ABSTRACT FROM AUTHOR]

Mineral aerosols form a key component of Earth's dynamic biogeochemical systems, yet their composition and mass are variable in time. We reconstruct patterns in mineral aerosol flux from East Asia, the second largest global dust source, in a peat mire in northern Japan. Using geochemical fingerprinting, we show for the past ~3600 years that high but variable tephra flux dominated regional aerosol loads. A human signal was discernible as elevated pollutant metals, along with East Asian mainland dust, identifiable by its geochemical signature. After ~700 years before the present, dust flux increased as the westerly jet intensified and moved south, the summer monsoon strength reduced, and agriculture expanded. From the 20th century, dust flux increased by two times. Attributable largely to human activity, this demarks a major change in aerosol export to the northwestern Pacific with accompanying increases in fluxes for key micronutrients and increased pollution flux by 16 times.