This study focused on the ability of the Antarctic bacterium Rhodococcus sp. strain AQ5-14 to survive exposure to and to degrade high concentrations of phenol at 0.5 g l-1. After initial evaluation of phenol-degrading performance, the effects of salinity, pH and temperature on the rate of phenol degradation were examined. The optimum conditions for phenol degradation were pH 7 and 0.4 g l-1 NaCl at a temperature of 25°C (83.90%). An analysis using response surface methodology (RSM) and the Plackett-Burman design identified salinity, pH and temperature as three statistically significant factors influencing phenol degradation. The maximum bacterial growth was observed (optical density at 600 nm = 0.455), with medium conditions of pH 6.5, 22.5°C and 0.47 g l-1 NaCl in the central composite design of the RSM experiments enhancing phenol degradation to 99.10%. A central composite design was then used to examine the interactions among these three variables and to determine their optimal levels. There was excellent agreement (R2 = 0.9785) between experimental and predicted values, with less strong but still good agreement (R2 = 0.8376) between the predicted model values and those obtained experimentally under optimized conditions. Rhodococcus sp. strain AQ5-14 has excellent potential for the bioremediation of phenol.

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.

In Antarctica, amphipods form a highly diverse group, occupy many different ecological niches and hold an important place in food webs. Here, we aimed to test whether differences in Antarctic amphipod feeding habits were reflected in their mandible morphology, and if mouthpart specialization could be used to describe amphipod trophic ecology. To do so, we compared mandible morphology in nine species spanning seven families and five functional groups (grazers, suspension feeders, generalist predators, specialist predators and scavengers). Mandible morphology adequately depicted some aspects of amphipod trophic ecology, such as the trophic level at which animals feed or their degree of dietary specialization. On the other hand, links between mandible morphology and amphipod diet were seldom unambiguous or straightforward. Similar adaptations were found in distinct functional groups. Conversely, mandible morphology could vary within a single functional group, and phylogenetic effects sometimes complicated the interpretation of form-function relationships. Overall, mandible morphology on its own was generally not sufficient to precisely predict amphipod feeding strategies. However, when combined with other methods (e.g. gut contents, trophic markers), it constitutes a valuable source of information for integrative studies of amphipod ecological diversity in the Southern Ocean.

Iron-rich meteorites are significantly underrepresented in collection statistics from Antarctica. This has led to a hypothesis that there is a sparse layer of iron-rich meteorites hidden below the surface of the ice, thereby explaining the apparent shortfall. As standard Antarctic meteorite collecting techniques rely upon a visual surface search approach, the need has thus arisen to develop a system that can detect iron objects under a few tens of centimetres of ice, where the expected number density is of the order one per square kilometre. To help answer this hypothesis, a large-scale pulse induction metal detector array has been constructed for deployment in Antarctica. The metal detector array is 6 m wide, able to travel at 15 km h-1 and can scan 1 km2 in ~11 hours. This paper details the construction of the metal detector system with respect to design criteria, notably the ruggedization of the system for Antarctic deployment. Some preliminary results from UK and Antarctic testing are presented. We show that the system performs as specified and should reach the pre-agreed target of the detection of a 100 g iron meteorite at 300 mm when deployed in Antarctica.

In this study, we aim to analyse the glacier dynamics of land-terminating glaciers in King George Island (Antarctica) between 1956 and 2018. Glacial fluctuations are estimated using space-borne remote sensing data (SPOT, Landsat, PlanetScope, Sentinel-1, Sentinel-2, WorldView-2 and TanDEM-X). The eastern sector of Warszawa Icefield witnessed continuous glacier retreat during 1979–2018 (surface loss of 30%). The decreases in the ice-covered areas of the Tower, Windy, Ecology, Baranowski and Sphinx glaciers were 70%, 31%, 25%, 25% and 21%, respectively, with their accumulation area ratios (AARs) exhibiting negative mass balances. The winter air temperature was cooler during the 1970s with warming trends in the 1980s and early 2000s followed by a cooling trend until the present day. However, the annual time series has shown high interannual variability in air temperature during these periods. We show that the AAR, dimensions, length, frontal elevation, maximum elevation, slope and changes in the terminus position influence the glacier response to climate change at various timescales. Furthermore, three geomorphic activity intensity zones and a complete paraglacial sequence are identified while contrasting the proglacial systems. Overall, subglacial deposits predominate and indicate that meltwater flows on the bed, producing wet-based thermal regimes.

Differences in the decadal trend in the winter surface temperature in the northern and southern Antarctic Peninsula have been analysed. Time series from the two stations Esperanza and Faraday/Vernadsky since the early 1950s are used. The two time series are strongly correlated only during the 1980s and 1990s when their variability and trends are associated with both the Niño-4 region and Southern Annular Mode impacts. The winter cooling at the Faraday/Vernadsky station contrasts with the winter warming at the Esperanza station during the period of 2006–17. The different temperature trends are accompanied by weak correlations between the temperatures at these two stations. Linearly congruent components of the station temperature trends in 2006–17 indicate a dominant contribution of Southern Annular Mode (tropical sea surface temperature anomalies) to warming (cooling) in the northern (southern) Peninsula. Distinctive impacts of climate modes are observed in combination with the recent deepening of the negative sea-level pressure anomaly to the west of the peninsula and the related change in the zonal and meridional wind components. These factors apparently contribute to the occurrence of the boundary that crosses the peninsula and divides it into sub-regions with warming and cooling.