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Human driven changes such as increases in oceanic CO2, global warming, petroleum hydrocarbons and heavy metals may negatively affect the ability of marine calcifiers to build their skeletons/shells, especially in polar regions. We examine spatio-temporal variability of skeletal Mg-calcite in shallow water Antarctic marine invertebrates using bryozoan and spirorbids as models in a recruitment experiment of settlement tiles in East Antarctica. Mineralogies were determined for 754 specimens belonging to six bryozoan species (four cheilostome and two cyclostome species) and two spirorbid species from around Casey Station. Intra- and interspecific variability in wt% MgCO3 in calcite among most species was the largest source of variation overall. Therefore, the skeletal Mg-calcite in these taxa seem to be mainly biologically controlled. However, significant spatial variability was also found in wt% MgCO3 in calcite, possibly reflecting local environment variation from sources such as freshwater input and contaminated sediments. Species with high-Mg calcite skeletons (e.g. Beania erecta) could be particularly sensitive to multiple stressors under predictions for near-future global ocean chemistry changes such as increasing temperature, ocean acidification and pollution.

The Talbragar Fish Bed is one of Australia's most important Jurassic deposits for freshwater fishes, land plants and aquatic and terrestrial insects. The site has yielded many well preserved fossils, which has led to the formal description of numerous new species and higher taxa. The excellent preservation of many fossils has allowed detailed anatomical studies, e.g. of the early teleost fish Cavenderichthys talbragarensis (Woodward, 1895). Here we report on the fluorescent characteristics and mineral composition of a range of Talbragar fossils. Most specimens fluoresce under ultraviolet, blue and green light. Elemental and mineralogical analyses revealed that the Talbragar fossils consist predominantly of quartz (SiO2), a mineral that is likely to account for the observed fluorescence, with trace kaolinite (Al2Si2O5(OH)4) in some of the fish fossils. Rock matrices are predominantly composed of quartz and goethite (FeO(OH)). Closer inspection of a plant leaf (Pentoxylon australicum White, 1981) establishes fluorescence as a useful tool for the visualisation of anatomical details that are difficult to see under normal light conditions.

Potentially toxic constituents in traditional medicines remain a concern due to health risks posed to consumers. Thirty-six traditional medicines (TM) consisting of 14 Indian Ayurvedic Medicines, 11 Chinese Traditional Medicines and eleven Ghanaian Traditional Medicines were evaluated using Total Reflection X-ray Fluorescence Spectrometer (T-XRF) after microwave assisted acid digestion. Physiologically Based Extraction Test (PBET) was used to obtain bioaccessible elemental concentrations. Merck XVI multi-element standard were used to evaluate the accuracy of the analytical method. The concentrations of the elements were quantified in (mg kg−1): Cr (0.01–698), Mn (0.01–1140), Fe (15–73300), Ni (1–1340), Cu (3–8160), Zn (0.01–224). The greatest bioaccessible concentrations of arsenic was 0.80 mg kg−1 and 0.44 mg kg−1 in the gastric and intestinal phases respectively. In order to evaluate the human health risks from ingesting these TM, the Acceptable Daily Intake (ADI) was calculated for each medicine based on element-specific bioaccessibility-adjusted concentrations and results compared with the United States Environmental Protection Agency (USEPA) Reference Dose (RfD) limits. The Acceptable Daily Intake (ADI) values for risks were within the USEPA RfD. Hazard quotients (HQ) of TM were < 1, meaning elemental concentrations do not pose non-carcinogenic risks to adult consumers. In summary the methods applied in the study gives a new insight on human health risks of potentially toxic and essential micronutrients elements in TM.

Areas around western Vestfold Hills, East Antarctica, feature two sedimentary units in outcrops and excavations. Uppermost Dingle Sand is a gravelly, silty sand with boulders, which drapes bedrock ridges and more thickly covers valley floors and continues below modern sea level. Underlying Vestfold Beds are gravelly, muddy sands that are found in deeper valley fills. High-resolution aerial photography, topographic and bathymetric surveys, sediment grain size and field observations indicate that Dingle Sand formed as ablation till during the last deglaciation. Post-depositional modifications of Dingle Sand by decay of ground ice, mass movement, water, wind and marine transgression and regression have altered the texture, structure and fossil content in this region. Vestfold Beds are older, finer-grained tills. Indirect age estimation of Dingle Sand suggests deglaciation-age deposition with younger (Holocene) reworking in places, whereas Vestfold Beds may be as old as the Pliocene. These sediments post-date the early Pliocene Sørsdal Formation found on Marine Plain in southern Vestfold Hills. Identification of Dingle Sand as a separate, primarily glacial deposit helps clarify the glacial history of the Vestfold Hills. Evidence for marine modification of the deposits after deglaciation suggests that other regions might also have glacial deposits interpreted as marine because of post-depositional processes.

Advance and retreat of bounding glaciers and ice shelf controlled the balance of fresh vs marine water input and the nature of the microfossils on lake and epishelf lake floors. The fourth paper demonstrates that strong winds have blown from the east–north-east for much of the postglacial period, and the fifth paper describes the effects of sea-spray dispersal from marine inlets and evaporation basins on sediments and landscape. Future research undertaken in Bunger Hills, and similar ice-free areas, should be conducted through this small-scale agile approach, minimizing cost and environmental impacts.

In situ cosmogenic 10Be exposure dating, radiocarbon determinations, salt and sediment geochemistry, and rock weathering observations indicate that parts of Larsemann Hills, East Antarctica have been subaerially exposed throughout much of the last glacial cycle, with the last glaciation occurring prior to 100 ka bp. Salt-enhanced subaerial weathering, coupled with a paucity of glacial erratics, made exposure age dating challenging. Rapid subaerial surface lowering in some places means that some exposure ages may underestimate the true age of deglaciation. Despite this uncertainty, the data are consistent with the absence of overriding by a thick ice sheet during the Last Glacial Maximum ∼20–18 ka bp.

Terrestrial environments at Bunger Hills, East Antarctica, vary from vegetation-rich, little-weathered rock surfaces retaining glacial polish and striations near the glacier and ice-sheet margins to salty, vegetation-poor, extensively weathered regions near to and downwind of marine bays and inlets. Weathering forms include tafoni and orientated pits, which record former wind directions. Although salts are found all over Bunger Hills, the strongly weathered area is coincident with the distribution of halite (NaCl) and thenardite (Na 2 SO 4 ), both of which are derived from seawater and marine salt spray. Salts elsewhere in Bunger Hills are either subglacial calcium carbonates or rock weathering products including gypsum (CaSO 4 ⋅2H 2 O) and a range of rarer minerals. These other salt minerals do not weather rocks and sediment. The distribution of halite and thenardite acts as a major control on the geomorphology, sediment geochemistry and biogeography of Bunger Hills.

The directions of strong winds are important for the distribution of marine salt spray, rock weathering, lake chemistry and the distribution of vegetation in Bunger Hills, a coastal ice-free oasis in East Antarctica. Present-day strong winds (> 10 m s −1 ) dominantly blow from 118 ± 21 degrees true (°T; ± 1 SD). Orientated tafoni (weathering pits) might form in bedrock surfaces by salt and ice crystallization, thermal stress and saltating sand particles, recording the orientation of a strongly directional wind field since the last deglaciation, which commenced > 30 000 years ago. The orientations of these tafoni, at 101 ± 18°T for 686 measurements at 28 sites, are indistinguishable from the direction of modern-day strong winds (> 10 m s −1 ), indicating that the orientation of the slope of the ice sheet has been stable throughout the last 10 000 years during the Holocene.

Unglaciated coastal areas in East Antarctica provide records of past ice sheet and glacier fluctuations and subsequent environmental conditions. In this paper we review lithological, geochemical, diatom and radiocarbon data from sediment records from inland and epishelf lakes in Bunger Hills, East Antarctica. While some hilltops were unglaciated during the Last Glacial Maximum, till deposits in lake basins indicate infilling by glacier ice prior to the Holocene. Proglacial sedimentation occurred in lakes during the early Holocene. Around 9.6 ka bp , deposition of marine sapropel started under relatively warm climate conditions. Inland lakes were affected by high clastic input from meltwater runoff until c. 7.9 ka bp , when deposition became highly organic and biogenic proxies indicate a period of cooler conditions. Epishelf lakes experienced a decrease in water exchange with the ocean and increased freshwater input around 7.7 ± 0.2 ka bp and after 2.2 ka bp . This probably resulted from grounding line advances of the bounding glaciers, which could be either controlled by relative sea level (RSL) lowering and/or climate-driven glacier dynamics. The absence of marine sediments in the postglacial record of Algae Lake indicates that Holocene RSL probably reached a maximum at or below 10 m above present sea level.

In this paper, we synthesize recorded observations of moss, lichen and bird species in Bunger Hills, East Antarctica, and assess the role of environmental controls, including sediment, salinity, moisture and geology, on species' distributions. The distribution of snow petrels ( Pagodroma nivea ) appears to be associated with geology; they nest by preference in crevices in bedrock outcrops around the margins of the hills or wherever jointed cliffs are found. South polar skuas ( Catharacta maccormicki ) are seen throughout Bunger Hills, where they nest and prey on snow petrels. Mosses and lichens were most abundant around the ice margins where fresh snow and ice meltwater are abundant. In the central area of Bunger Hills, where the highest salt concentration in sediments is found and exposure to abrasion by wind-driven mineral sand grains and ice particles is greatest, mosses and lichens are reduced in abundance and diversity. Exposure of parts of Bunger Hills from the ice sheet throughout the Last Glacial Maximum, c. 20 ka bp , means that some land and lakes could have acted as regional refugia and as a locus of recolonization of other ice-free areas.