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This paper provides new insights into the long-term history of Aboriginal use of mountainous Victoria over the past 25,000 years. It presents results of excavations at Garden Range 2 rock art site located on the edge of the Strathbogie Ranges in central Victoria. The excavations were a research collaboration between the Taungurung Land and Waters Council (TLaWC) and Monash University. Results indicate possible ephemeral visitation by the Old People during the Last Glacial Maximum, clear evidence of occupation over the past 11,000 years, and increased activity since 1600 cal BP. The stone artefact assemblage is dominated by flakes of local quartz. Three igneous flakes from ground-edge axes, dating to after 700 cal BP, are contemporary with a grinding stone showing use-wear and residues from stone axe maintenance. The faunal assemblage is dominated by forest and grassland animals, such as macropod and emu, with mussel shells and fish bones indicating the use of nearby Seven Creeks. The rarity of ochre within sediments precludes insights into the age of rock art paintings on the shelter's surface. Fossil pollen documents the nineteenth-century European forest clearances, a period when Taungurung people's use of the site became unsafe. Unburnt fragments of rabbit and sheep bone suggest subsequent use of the site as a fox den. Garden Range 2 illustrates Aboriginal use of mountainous central Victoria during periods of significant environmental changes in the Early Holocene and possibly in the Late Pleistocene. These chronological patterns, including increased activity in the central Victorian uplands during the Late Holocene, match emerging chronological patterns of long-term use of other mountainous regions of southeastern Australia. How sites like Garden Range 2 relate to broader long-term Aboriginal use of more elevated sub-alpine and alpine (snow country) zones of central and eastern Victoria is a question for future archaeological research. [ABSTRACT FROM AUTHOR]

The dominant paradigm is that large tracts of Southeast Asia's lowland rainforests were replaced with a "savanna corridor" during the cooler, more seasonal climates of the Last Glacial Maximum (LGM) (23,000 to 19,000 y ago). This interpretation has implications for understanding the resilience of Asia's tropical forests to projected climate change, implying a vulnerability to "savannization". A savanna corridor is also an important foundation for archaeological interpretations of how humans moved through and settled insular Southeast Asia and Australia. Yet an up-to-date, multiproxy, and empirical examination of the palaeoecological evidence for this corridor is lacking. We conducted qualitative and statistical analyses of 59 palaeoecological records across Southeast Asia to test the evidence for LGM savannization and clarify the relationships between methods, biogeography, and ecological change in the region from the start of Late Glacial Period (119,000 y ago) to the present. The pollen records typically show montane forest persistence during the LGM, while δ13C biomarker proxies indicate the expansion of C4-rich grasslands. We reconcile this discrepancy by hypothesizing the expansion of montane forest in the uplands and replacement of rainforest with seasonally dry tropical forest in the lowlands. We also find that smooth forest transitions between 34,000 and 2,000 y ago point to the capacity of Southeast Asia's ecosystems both to resist and recover from climate stressors, suggesting resilience to savannization. Finally, the timing of ecological change observed in our combined datasets indicates an 'early' onset of the LGM in Southeast Asia from ~30,000 y ago. [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]

Soil erosion is a major environmental issue in Australia. It reduces land productivity and has off-site effects of decreased water quality. Broad-scale spatially distributed soil erosion estimation is essential for prioritising erosion control programs and as a component of broader assessments of natural resource condition. This paper describes spatial modelling methods and results that predict sheetwash and rill erosion over the Australian continent using the revised universal soil loss equation (RUSLE) and spatial data layers for each of the contributing environmental factors. The RUSLE has been used before in this way but here we advance the quality of estimation. We use time series of remote sensing imagery and daily rain Pall to incorporate the effects of seasonally varying cover and rainfall intensity, and use new digital maps of soil and terrain properties. The results are compared with a compilation of Australian erosion plot data, revealing an acceptable consistency between predictions and observations. The modelling results show that: (1) the northern part of Australia has greater erosion potential than the south; (2) erosion potential differs significantly between summer and winter; (3) the average erosion rate is 4.1 t/ha.year over the continent and about 2.9 x [10.sup.9] tonnes of soil is moved annually which represents 3.9 Vo of global soil erosion from 5% of world land area; and (4) the erosion rate has increased from 4 to 33 times on average for agricultural lands compared with most natural vegetated lands. Additional keywords: soil erosion, prediction, RUSLE, Australia., Introduction Soil erosion is a natural process that contributes to the evolution of the land surface. It is governed by topography, climate, soil, vegetation cover, and land use and management [...]