Bioaugmentation is a controversial strategy. In this work, the effect of the inoculum size and the absence of natural microflora on the efficiency of hydrocarbon removal were studied. Two levels of inoculum (106 and 109 CFU g-1) were applied to soil microcosms containing sterile (S6 and S9) and non-sterile (NS6 and NS9) oil contaminated Antarctic soil. Community controls (CC) and biostimulated autochthonous microflora (BAM) were also included. Total heterotrophic aerobic (THAB) and hydrocarbon degrading (HDB) bacteria as well as total petroleum hydrocarbons (TPH) were analysed. At day 0, THAB and HDB counts (CFU g-1) showed no differences among CC, BAM and NS6 but significantly higher values were observed in NS9 and S9. At day 60, three different levels of HDB were observed. The lower level was represented by CC (106 CFU g-1), a second group (5 x 107 CFU g-1) was represented by BAM, NS6, NS9 and S6, and the third level was constituted by S9 (1 x 109 CFU g-1). TPH values at day 60 decreased significantly in all systems excluding the controls. NS6, NS9, S6 and S9 were not different from those corresponding to BAM. Results suggest that the bioaugmentation of a chronically diesel fuel-contaminated Antarctic soil is unlikely to be profitable or beneficial.

Diatoms are important primary producers in present day Antarctic waters but their relative significance in the past is less clear. In this study we used long-chain diols to reconstruct Proboscia diatom productivity in shelf waters of the western Antarctic Peninsula over the last 8500 yr. Biomarker lipid analysis revealed the presence of a suite of long-chain diols in the sediments, mainly comprising the C28 and C30 1,14-diol isomers derived from Proboscia diatoms and C28 and C30 1,13-diols derived from other unknown algae. The relative importance of Proboscia diatoms was assessed using the relative abundances of 1,14-diols versus 1,13-diols, which showed that Proboscia diatoms were relatively more abundant during the Late Holocene, suggesting that stronger upwelling of circumpolar waters occurred at that time. The variations in the diol index strongly correlate with melt events in the Siple Dome ice core, suggesting that the climatic processes responsible for changes in mean summer temperature, open marine influence and atmospheric cyclonic activity recorded at Siple Dome, also controlled the productivity of Proboscia diatoms on the western Antarctic Peninsula region.

The ecosystem of the isolated Prince Edward Islands, south of the African continent, is strongly impacted by ocean eddies that are associated with the eastward flowing Antarctic Circumpolar Current. Satellite altimetry has revealed that the archipelago lies in a region of enhanced eddy kinetic energy. In the late 1990s it became apparent that in order to understand the influence of these eddies on the islands’ ecosystem, the source, trajectory and nature of these eddies needed to be studied and understood. To this end a special research project with a strong ocean-going component was designed, the DEIMEC (Dynamics of Eddy Impact on Marion’s ECosystem) programme. In this review we focus on the physical oceanography and summarize the aims, the results and the successes of this South African research initiative. In the vicinity of the Prince Edward Islands, an average of three intense well-defined eddies is observed per year. Their advection speeds are of the order of a few kilometres per day and longevities of 7–11 months. These features, of c. 100 km in diameter and reaching depths of at least 1000 m, transport anomalous water masses across the Polar Frontal Zone.

Although existing research regarding the experience of Antarctic employment has primarily focused on the absence period (i.e. the period of time in which the expeditioner physically works in Antarctica), it has been repeatedly demonstrated that the majority of expeditioners experience positive outcomes associated with their time ‘on the ice’ despite transient (and frequently subclinical) physical, psychological, and social difficulties. Research strategies directed towards the individual experience of the expeditioner have not been able to fully account for the processes underpinning the adjustment processes that have facilitated seemingly resilient and growth outcomes. Similarly, insufficient research attention has been given to the separate phases of Antarctic employment, nor the potential interdependence between them, which may also provide further insight into these processes. To address these issues it has been argued that an approach incorporating individual, interpersonal, and organizational factors throughout the Antarctic employment experience, from pre-departure through absence, reunion, and reintegration, be adopted.

We review the current scientific knowledge about Antarctic Blue Ice Areas (BIAs) with emphasis on their application for palaeoclimate studies. Substantial progress has been made since the review by Bintanja (1999), in particular dating the archive of ancient ice found on the surface of BIAs has progressed with advances in 14C measurements, tephrachronology, and geomorphological evidence giving better constraints to more sophisticated ice flow models. Flow modelling also provides information about past changes in ice flow velocities, accumulation rates and ice sheet elevation. The availability of gas composition in vertical cores from BIAs allows matching to well-dated global records of greenhouse gas variability over the last glacial-interglacial cycle and longer. It is clear from the limited number of studies to date that BIAs from different regions have quite different histories of formation and preservation, and that they are intimately linked to the response of their surrounding ice sheets to climate variability on glacial-interglacial time-scales. Looking to the future, climate records from BIAs are expected to provide information on variations in Southern Ocean processes as well as ice sheet evolution within the East Antarctic ice sheet at the thermal transition from cold based to warm based ice.

After a decade of research, New Zealand’s Latitudinal Gradient Project (LGP) now includes primary sites from Cape Hallett (72°S) to the Darwin Glacier (80°S), while additional observations extend the latitudinal transect from 84°S to sub-Antarctic regions. The LGP has been structured around a hypothesis that, in a frigid continent, ice dynamics is the key ecosystem variable. For terrestrial environments, two aspects of ice dynamics appear to underlie much of the observed variability. Firstly, the aridity of the region makes the transition from ice to water a key ecological factor, and secondly, the legacy of ice dynamics dating as far back as the Pliocene is imprinted on biogeography. These factors operate at difference temporal and spatial scales and neither is monotonically related to latitude. Both are also complicated by meso-scale cross gradients of altitude and distance from the sea and micro-scale local variability. Whilst climate does vary on a broad-scale, differences within the northern and central parts of Victoria Land that the LGP has so far examined are insufficient to impose any overarching effect that can overwhelm these more local effects. The result is a multiple-scale patchwork of habitats and communities, more or less replicated across the transect, in which variability at any given latitude generally exceeds variability between latitudes. A lesser quantum of research has been directed at marine ecosystems, but here there is a similar picture of local variability dominating within the Ross Sea, with significant latitude-scale effects only emerging when transects are extended into maritime- and sub-Antarctic regions. It is implicit, but not specifically recognized in the LGP context, that a further confounding effect on the interpretation of ‘transect’ information is the multiple stressor concept that requires a simultaneous analysis of interacting (synergistic or antagonistic) factors and environmental responses. As the LGP continues to extend further south, climate is expected to become more extreme, and water availability may change sufficiently for loss of habitat and species diversity to occur. Here we discuss options for refining the LGP approach to optimize its potential for understanding variability, and the factors underpinning this, in the Ross Sea Sector.

This investigation attempts to determine which environmental parameters of the bottom water and sediment control recent foraminifera fauna at Ezcurra Inlet (King George Island, Antarctica), using data collected during four summers (2002/03, 2003/04, 2004/05 and 2006/07). The study revealed that Ezcurra Inlet contain typical Antarctic foraminifera fauna with three distinct assemblages and few differences in environmental parameters. The species Bolivina pseudopunctata, Fursenkoina fusiformis, Portatrochammina antarctica, and Adercotryma glomerata were abundant in the samples. An elevated abundance, richness and diversity were common at the entrance of the inlet at depths greater than 55 m, where the inlet was characterized by low temperatures and muddy sand. In the inner part of the inlet (depth 30–55 m), richness and diversity were low and the most significant species were Cassidulinoides parkerianus, C. porrectus, and Psammosphaera fusca. Shallow waters showed low values of richness and abundance and high temperatures coupled with coarser sediment. In areas with high suspended matter concentrations and pH values associated with low salinity the most representative species were Hippocrepinella hirudinea and Hemisphaerammina bradyi.

N2-fixation is an important mechanism in microbial mats of the McMurdo Ice Shelf as nitrogen sources are limited. Here we applied molecular analyses of the N2-fixing diversity in cyanobacterial dominated microbial mats in a meltwater pond, known as Orange Pond, on the McMurdo Ice Shelf. Phylogenetic analyses of nifH genes and nifH gene transcripts were performed in association with acetylene reduction assay measurements. Eighteen phylotypes with the highest similarities to cyanobacteria, firmicutes, beta-, gamma- and deltaproteobacteria, spirochaetes and verrumicrobia were identified. All cyanobacterial nifH phylotypes grouped solely in the genus Nostoc spp. Clone-library analysis of nifH gene transcripts only identified sequences with a highest match to Nostoc spp. and acetylene reduction activity was identified in the presence of light and absence of 3-(3,4-dichlorophenyl)-1,1-dimethyl urea. These molecular results indicate that a variety of bacterial phyla possess the ability to fix nitrogen. However, under the tested conditions the only organisms actively transcribing nifH genes were Nostoc spp. This underlines the importance of Nostoc for the nitrogen budget on the McMurdo Ice Shelf.

Despite supporting productive ecosystems in the high latitudes, the relationship between macro- and micronutrients in sea ice environments and their impact on surface productivity is poorly documented. In seawater, the macronutrient phosphate and the micronutrient cadmium follow similar distributions, which are controlled by biological processes in surface waters. We investigated cadmium and phosphate in sea ice brine, and the biological and physical processes controlling their distribution. Cadmium concentrations in sea ice brine ranged from 0.09–2.4 nmol kg-1, and correlated well with salinity. Our results show that micronutrients in sea ice are most probably sourced from the seawater from which it froze rather than external sources such as atmospheric deposition. The weak correlation between sea ice cadmium and phosphate, and the positive relationship between cadmium and biomass, suggests against biological uptake being a principal control over micronutrient distribution even in a highly productive setting. Instead, brine expulsion and dilution play a dominant role in cadmium distribution in sea ice. Nutrient dilution within brine channels during melting, and contrasting sea ice and open water phytoplankton populations, suggests that late spring sea ice is not a significant source of nutrients or biomass to seawater. We suggest that future changes in sea ice seasonality may impact nutrient distribution and Antarctic marine ecosystems.

The introduction of invasive species is one of the greatest threats to Earth’s biodiversity, as they can reduce native biodiversity and alter ecosystem structure and function. Currently, the only two known non-native terrestrial invertebrates in Antarctica are the chironomid midge Eretmoptera murphyi and the enchytraeid worm Christensenidrilus blocki. These invertebrates were probably introduced to ground near Signy Research Station, South Orkney Islands, during transplantation experiments in the late 1960s. Between 2007 and 2009, this study surveyed the area around the introduction site for midge larvae and worms to assess any change over the last four decades in their spatial distribution, habitat preference and colonization status. Eretmoptera murphyi was found in concentrations up to 4.1 × 105 larvae m-2 (mean 2.1 × 104 larvae m-2) at distances of up to 220 m from the probable introduction site (c. 35 000 m2), while C. blocki was only found close to the introduction site in low numbers. Significantly more E. murphyi larvae were found in peat and dead organic material (3.34 × 104 m-2) than in stony soil and gravel (1.52 × 104 m-2) or living moss and other plant material (1.16 × 104 m-2). Eretmoptera murphyi can no longer be considered a persistent alien as it clearly expanding its distribution, while C. blocki remains a persistent alien species.

We present direct terrestrial evidence of ice volume change of the Darwin and Hatherton glaciers which channel ice from the Transantarctic Mountains into the Ross Ice Shelf. Combining glacial geomorphology with cosmogenic exposure ages from 25 erratics indicates a pre-LGM ice volume at least 600 m thicker than current Hatherton ice elevation was established at least 2.2 million years ago. In particular, five erratics spread across a drift deposit at intermediate elevations located below a prominent moraine feature mapped previously as demarcating the LGM ice advance limits, give a well-constrained single population with mean 10Be age of 37.0 ± 5.5 ka (1σ). At lower elevations of 50–100 m above the surface of Lake Wellman, a further five samples from within a younger drift deposit range in exposure age from 1 to 19 ka. Our preferred age model interpretation, which is partly dependent on the selection of a minimum or maximum age-elevation model, suggests that LGM ice volume was not as large as previously estimated and constrains LGM ice elevation to be within ± 50 m of the modern Hatherton Glacier ice surface, effectively little different from what is observed today.

The permanent ice covers of the McMurdo Dry Valley lakes, Antarctica, are colonized by a diverse microbial assemblage. We collected ice cores from Lakes Fryxell, Hoare and Bonney. Propidium monoazide (PMA) was used in combination with quantitative PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE) to examine membrane integrity of prokaryotes in these extreme environments. PMA selectively penetrates cells with compromised membranes and modifies their DNA resulting in the suppression of PCR amplification. Our results based on analysis of 16S rRNA genes demonstrate that despite the hostile conditions of the Dry Valleys, the permanent ice covers of the lakes support a ‘potentially viable’ microbial community. The level of membrane integrity, as well as diversity, was higher in samples where sediment was entrapped in the ice cover. Pronounced differences in the fraction of cells with intact and compromised cell membranes were found for Lake Fryxell and east lobe of Lake Bonney, both expressed in differences in DGGE banding patterns and qPCR signal reductions. Limitations in the ability to distinguish between intact or compromised cells occurred in samples from Lake Hoare and west lobe of Lake Bonney due to low DNA template concentrations recovered from the samples.

Commercial, shipborne tourism along the Antarctic Peninsula grew exponentially between 1989–90 and 2007–08, raising concern about the impact such activity may have on the environment of the region. Previous analyses of Antarctic tourism have focused narrowly on patterns of visitation and potential impacts at terrestrial landing sites. Here, using 19 years of passenger landing statistics and five years of reconstructed ship itineraries, we explore patterns of tourism activities in the Antarctic Peninsula region using a spatially explicit network theory analysis of ship itineraries. We find that passenger landings and marine traffic are highly concentrated at a few specific locations and that growth in tourism activity occurred disproportionally rapidly at these sites relative to growth in visitation of the Peninsula as a whole. We conclude by discussing the pros and cons of spatially concentrated tourism activity and the associated implications for ecosystem management.

A review of the collembolan fauna of the South Shetland Islands is presented. Cryptopygus nanjiensis Yue & Tamura is synonymized with C. antarcticus Willem. A record of Tullbergia mediantarctica Wise from King George Island is considered a misidentification of Tullbergia mixta Wahlgren and Tillieria penai Weiner & Najt, described from the same island, is synonymized with T. mixta. The current fauna stands at eleven species, of which at least three are introduced. A checklist of Collembola currently considered to occur in the South Shetland Islands is supplied with distributional data.