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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]

This paper presents the results of an archaeological investigation into anthropogenic earth (oven) mounds located on the Murray River floodplain at Calperum Station in the Renmark region of South Australia. Six mounds were excavated and their contents examined. Sediment analyses were also conducted to assess magnetic susceptibility, grain size and loss on ignition. Radiocarbon age estimates were obtained on shell and charcoal. Mound contents primarily included anthropogenically burnt clay (heat retainers), charcoal, fragments of mussel shell as well as very minor quantities of other faunal material and stone artefacts (which were consistent with previous lithic assessments for the region). The radiocarbon age determinations from 15 samples indicate that mounds were formed by Aboriginal people on the Calperum floodplain from at least 3981–3723 cal BP and utilised up to the time of European invasion. The very minimal amount of faunal remains (other than mussel shell), artefacts and a general lack of other material evidence apart from clay heat retainers, confirms that these features were single purpose and not used as living areas. Sediment analyses and radiocarbon dates indicate a high degree of homogeneity within mounds but provide insights into an economic transition on the Calperum floodplain, at around 4000 cal BP involving a food-production procurement strategy based on heat retainer technology and the exploitation of emergent macrophytes. [ABSTRACT FROM AUTHOR]

A revised Holocene sea-level history for the southern Gulf of Carpentaria is presented based on new data from the South Wellesley Archipelago and age recalibration of previous research. Results confirm that rising sea levels during the most recent post-glacial marine transgression breached the Arafura Sill ca. 11,700 cal. yr BP. Sea levels continued to rise to ca. -30 m by 10,000 cal. yr BP, leading to full marine conditions. By 7700 cal. yr BP, sea-level reached present mean sea-level (PMSL) and continued to rise to an elevation of between 1.5 m and 2 m above PMSL. Sea level remained ca. + 1.5 between 7000 and 4000 cal. yr BP, followed by rapid regression to within ± 0.5 m of PMSL by ca. 3500 cal. yr BP. When placed into a wider regional context results from this study show that coastal landscape evolution in the tropical north of Australia was not only dependent on sea-level change but also show a direct correlation with Holocene climate variability. Specifically, the formation and preservation of beach-rock deposits, intertidal successions, beach and chenier ridge systems hold valuable sea-level and Holocene climate proxies that can contribute to the growing research into lower latitude Holocene sea-level and climate histories. [ABSTRACT FROM AUTHOR]

We present a new well dated Holocene record of environmental change from Little Llangothlin Lagoon in eastern Australia derived from aquatic plant macrofossils, macroscopic charcoal flux, and sediment stratigraphy from multiple cores. Little Llangothlin was an ephemeral freshwater wetland exhibiting frequent dry phases between 9800 and 9300 calendar years before present (cal. yr BP). There was a switch to a more positive water balance after 9300 cal. yr BP, and by 8000 cal. yr BP, there was a lake that persisted until 6100 cal. yr BP. The period between 6100 and 1000 cal. yr BP was much drier, and there is no evidence for a permanent lake during this period. The Little Llangothlin record provides evidence for a wet phase during the Early to Middle Holocene (9000–6000 cal. yr BP) from the boundary region between temperate and tropical influences in eastern Australia. We propose that generally enhanced circulation after 9000 cal. yr BP explains the pattern of increasing moisture at the site at this time. The later Holocene climate at the site is consistent with other sites in south east Australia with a switch to generally drier conditions after 6000 cal. yr BP. [ABSTRACT FROM AUTHOR]

Temperate Highland Peat Swamps on Sandstone (THPSS) are a form of topogenous mire found on the plateau areas of eastern Australia. They are well recognised for their ecological value, but our understanding of their geomorphic structure, function and evolution remains limited. Across 19 sites, the valley fills of THPSS comprise sequences of mineral-rich sand and loam deposits. Basal sand and gravel sediments have low organic content and low carbon to nitrogen (C:N) ratios (a measure of peat formation) and are dated between 15.3 and 9 kyr cal. BP, with outliers back to 44 kyr cal. BP. These units reflect mineral-sediment trapping and accumulation on the valley floor. The transition to ‘swamp’ conditions through paludification occurred between 15.2 and 10.3 kyr cal. BP in some systems, and between 7.6 and 1.4 kyr cal. BP in other, adjacent valleys. These ‘swamp’ sediments comprise a package of units, progressing upward from fine cohesive sands, through assemblages of alternating organic sands to surface organic fines. These beds vary in texture from loams to sands and have a range of organic matter content (from 7.6% to 79.9%) and C:N ratios (from 15 to 58). The surface organic fines at 0 and 100 cm depth range in age from 13.1 to 0.7 kyr cal. BP. The composition and age structure of the valley fill suggest a mix of allogenic and autogenic controls are responsible for the formation of these swamps, but a regional model of THPSS evolution is emerging. Given these ‘peatlands’ have formed under a climate that experiences significant inter-annual variability in rainfall, conditions for peat formation are localised and not directly equivalent to those documented internationally. [ABSTRACT FROM PUBLISHER]

Lake sediment records from three lakes in the South Island of New Zealand were examined to determine the effects of human (Māori and European) impacts on the lake catchments during the Late Holocene. Major changes in lake biota occurred in the Early to Middle Holocene (11,000–6000 cal. yr BP), but there were no major changes between c. 6000 cal. yr BP and the time of human impact. Intensive Māori forest clearance occurred here between c.ad 1200 and 1600, which is consistent with other New Zealand records. Catchment erosion and increased sedimentation probably occurred in all of the studied lakes, but the most obvious changes occurred in Lake Clearwater and the Māori Lakes. There was evidence for gravity-induced slumping of the littoral sediments in Lake Clearwater due to increased sediment loading, and the outflow from the Māori Lakes was blocked by a migrating alluvial fan. The erosion of sediment (and nutrients) from the lake catchments led to eutrophication, but increases in lake depth were just as important in two of the lakes. Increased water depth was caused by damming of the Māori lakes outflow by a migrating alluvial fan. Reduced evapotranspiration following deforestation would also have led to increased water yield in lake catchments. European impacts were minor compared with the impacts of Māori deforestation, and all lakes display different levels of recovery towards pre-human impact conditions. Complete recovery is prevented by permanent changes in catchment hydrology and probable internal feedback mechanism such as wind-induced sediment re-suspension in the larger lakes. [ABSTRACT FROM AUTHOR]

The Gunditjmara people developed a socio-economic system based on the modification of wetland ecosystems associated with the Mt Eccles lava flow primarily for sustainable production and management of the highly nutritious shortfin eel (Anguilla australis). This paper examines the environmental history of these landscapes since their inception about 30 000 years ago, through palaeoecological analysis of sediment cores from associated lakes and swamps, in order to contribute to an understanding of the causes and timing of cultural transformation. Two records cover the whole of the 30 000 year history of the landscape while two others provide evidence of change within the Holocene. A great deal of variation within the landscape is revealed, both temporally and spatially, with opportunities for human exploitation through the whole recorded period. Although most features of the records can be explained by natural landscape development and climate change, some human modification can be suggested from around the Pleistocene-Holocene transition while more obvious indications of management relating to eel aquaculture are evident from about 4000 cal. yr BP that appear to include adaptations to the onset of a drier and more variable climate. The study has implications for the explanation of intensification of settlement in Australia more generally within the mid to late Holocene. [ABSTRACT FROM AUTHOR]