Roots of nine of the 12 vascular plant species present on sub-Antarctic Heard Island were examined for mycorrhizae. All species examined had some type of mycorrhization with most possessing associations with vesicular-arbuscular mycorrhizae or dark septate mycorrhizae. The degree of mycorrhization varied considerably across sites. Sampled plants were growing on either morainic or beach substrates with some areas exposed only in the last century. As mycorrhizae are known to play an important role in the nutrient uptake by host-plants, these results support the idea that mycorrhizae can influence the capacities of plants to colonize in cold and low-nutrient environments such as sub-Antarctic glacier forelands. Comparisons with data from other sub-Antarctic islands are made.

The risks posed by a range of acoustic scientific instruments were assessed by the construction of matrices of scale and likelihood. We recognized six levels of impact ranging from none or short term, minimal behavioural response (Level 1) to multiple injuries and fatalities and/or compromised populations (Level 6) and six levels of likelihood ranging from “Expected in almost all instances” (Level 1) to “cannot see how it could happen” (Level 6). Typical scientific instruments ranging from acoustic releases to large air gun arrays were assessed. To provide a perspective for the risks of scientific operations, other activities were also ranked. These included large chemical explosions, submarine detection sonars implicated in some mass strandings of cetaceans and normal Antarctic shipping activities. The conclusion reached was that most scientific instruments pose a similar or lower risk than normal shipping operations. High source-level equipment poses some risk to individual animals' hearing and so should be mitigated. Likewise, survey planning should be designed to avoid trapping animals in narrow, constricted sea ways. Long term, cumulative impacts are still difficult to detect in areas with greater anthropogenic noise than the Antarctic but we concluded that any possible long term impacts should be mitigated by maintaining the low levels of activity using high source-level equipment through data sharing and survey planning.

In a study designed to elucidate the factors that might differentially affect the well being and biology of Adélie penguins (Pygoscelis adeliae) that breed in colonies of different size, we investigated the predation rates on penguins by leopard seals (Hydrurga leptonyx) over a period of six years. The study colonies varied in size across the full range for this penguin species, contrasting with previous studies in which data were gathered only at very large colonies, and only in single years. The number of seals present varied directly with the amount of penguin traffic in the areas near the beach, where most predation takes place. Seals were present persistently only when penguin traffic exceeded about 250 penguins per hour. Predation rates also varied with penguin traffic in a curvilinear fashion, leveling off where traffic exceeded about 1200 penguins per hour. With respect to predation, it appears to be advantageous for Adélie penguins to nest in very small or very large colonies. At large colonies, the number of penguins moving to and from the colony ‘swamp’ the seals' predatory efforts, thus reducing the chances that an individual penguin will be taken. Small colonies are of little interest to the seals.

A model was used to simulate primary production of benthic microbial mats in Lake Hoare, southern Victoria Land, Antarctica, and to compare potential benthic to planktonic production. Photosynthetic and respiratory characteristics of mats from five depths in the lake were extrapolated across depth, surface area and time, to estimate whole-lake, annual net primary production. Variation in under-ice light regimes resulting from changes in ice thickness and transparency, and light extinction in the water column was examined, and an uncertainty analysis of key model parameters performed. Daily mat production estimates were 0.98–37.83 mg C m−2 d−1, depending on depth and PAR, whereas in situ production of phytoplankton averaged 15% of this. Annual patterns of mat production achieved maximum rates of 15–16 g C m−2 y−1 at 10 m depth when ≥ 5% of ambient PAR was transmitted through the ice covering the lake; observed transmittance values were usually ≤ 5%. Increasing underwater PAR had little effect above 5–7% transmittance, as photosynthesis became saturated at this level. Uncertainties in estimates of maximum photosynthetic rate (Pmax), initial slope of photosynthetic-light response (α) and maximum respiration rate (Rmax) explained 72–99% of uncertainty in model behaviour; Pmax was increasingly important at high light levels whereas α was more important at low light levels, however Rmax exerted the greatest influence under most conditions.

Three hydrocarbon-degrading Rhodococcus strains isolated from polluted Antarctic soils proved to be closely related despite their different origins. Strains had a similar hydrocarbon degradation pattern and optimum growth temperature ranged between 25ºC and 30ºC, showing that strains are psychrotolerant but not psychrophiles. Specific growth rate on rich media ranged between 0.12 and 0.21 h−1, higher than those observed on hydrocarbons as carbon source. Results suggest that in Antarctic contaminated soils, closely related Rhodococcus strains are present and could play an important role in decontamination. Microcosm systems showed that, although the natural microflora respond significantly to the pollutants, bioaugmentation with Rhodococcus strain (ADH), improved biodegradation either alone or mixed with a hydrocarbon-degrading Acinetobacter strain. In comparison with microcosm where only ADH was inoculated, a non-significant decrease in hydrocarbon concentration was observed when ADH was inoculated as mixed culture with a previously tested strain. Pollutants dramatically reduced bacterial groups in soils resulting in a dominance of Pseudomonas. Microcosms showed that when natural microflora has no previous history of exposure to the pollutants, bioaugmentation with autochthonous strains improves degradation of the contaminants. The positive response of the native bacteria to the pollutants leaves the question open as to whether bioaugmentation is necessary when soils have a long previous exposure to hydrocarbons.

The prediction of crustal motions and gravity change driven by glacial isostatic adjustment (GIA) in Antarctica is critically dependent on the reconstruction of the configuration and thickness of the ice sheet during the Late Pleistocene and Holocene. The collection and analysis of field data to improve the reconstruction has occurred at an accelerated pace during the past decade. At the same time, space-based imaging and altimetry, combined with on-ice velocity measurements using Global Positioning System (GPS) geodesy, has provided better assessments of the present-day mass balance of the Antarctic ice sheet. Present-day mass change appears to be dominated by deglaciation that is, in large part, a continuation of late-Holocene evolution. Here a new ice load model is constructed, based on a synthesis of the current constraints on past ice history and present-day mass balance. The load is used to predict GIA crustal motion and geoid change. Compared to existing glacioisostatic models, the new ice history model is significantly improved in four aspects: (i) the timing of volume losses in the region ranging from the Ross Sea sector to the Antarctic Peninsula, (ii) the maximum ice heights in parts of the Ellsworth and Transantarctic Mountains, (iii) maximum grounding line position in Pine Island Bay, the Antarctic Peninsula, and in the Ross Sea, (iv) incorporation of present-day net mass balance estimates. The predicted present-day GIA uplift rates peak at 14–18 mm yr−1 and geoid rates peak at 4–5 mm yr−1 for two contrasting viscosity models. If the asthenosphere underlying West Antarctica has a low viscosity then the predictions could change substantially due to the extreme sensitivity to recent (past two millennia) ice mass variability. Future observations of crustal motion and gravity change will substantially improve the understanding of sub-Antarctic lithospheric and mantle rheology.

Dimethyl sulphide (DMS) and its oxidation products (e.g. methanesulphonic acid, MSA) are known to play important roles in atmospheric chemistry (Liss et al. 1997). They act as source of atmospheric particles, and affect the radiative balance of the atmosphere directly by absorbing and scattering solar radiation or indirectly by forming cloud condensation nuclei, which enhance cloud albedo (Charlson et al. 1987, Curran & Jones 2000).

Predicting the effects of climate change on Antarctic terrestrial vegetation requires a better knowledge of the ecophysiology of common moss species. In this paper we provide a comprehensive matrix for photosynthesis and major environmental parameters for three dominant Antarctic moss species (Bryum subrotundifolium, B. pseudotriquetrum and Ceratodon purpureus). Using locations in southern Victoria Land, (Granite Harbour, 77°S) and northern Victoria Land (Cape Hallett, 72°S) we determined the responses of net photosynthesis and dark respiration to thallus water content, thallus temperature, photosynthetic photon flux densities and CO2 concentration over several summer seasons. The studies also included microclimate recordings at all sites where the research was carried out in field laboratories. Plant temperature was influenced predominantly by the water regime at the site with dry mosses being warmer. Optimal temperatures for net photosynthesis were 13.7°C, 12.0°C and 6.6°C for B. subrotundifolium, B. pseudotriquetrum and C. purpureus, respectively and fall within the known range for Antarctic mosses. Maximal net photosynthesis at 10°C ranked as B. subrotundifolium > B. pseudotriquetrum > C. purpureus. Net photosynthesis was strongly depressed at subzero temperatures but was substantial at 0°C. Net photosynthesis of the mosses was not saturated by light at optimal water content and thallus temperature. Response of net photosynthesis to increase in water content was as expected for mosses although B. subrotundifolium showed a large depression (60%) at the highest hydrations. Net photosynthesis of both B. subrotundifolium and B. pseudotriquetrum showed a large response to increase in CO2 concentration and this rose with increase in temperature; saturation was not reached for B. pseudotriquetrum at 20°C. There was a high level of variability for species at the same sites in different years and between different locations. This was substantial enough to make prediction of the effects of climate change very difficult at the moment.

A field experiment investigating the effect of oil contamination on benthic microbial communities was conducted near Casey Station, East Antarctica. Defaunated sediment was treated with a mixture of Special Antarctic Blend diesel and lubricating oil and deployed in three different bays for eleven weeks. A molecular fingerprinting technique, denaturing gradient gel electrophoresis (DGGE), was used to investigate the microbial community structure. The variation between replicate samples within treatment groups indicates that the benthic microbial populations are very diverse and evenly distributed. Comparisons to determine the significance of both deployment location and hydrocarbon treatment showed that the greatest effect was from a combination of location and treatment. Detailed analysis suggests that subtle differences may be obscured by variability introduced by PCR and gel stages in DGGE, undermining this experimental approach. It is concluded that both location and hydrocarbon contamination influenced the development of the microbial communities but that the effect of hydrocarbon treatment varied with location. This has important implications for the design of future experiments on the effect of hydrocarbons on benthic communities, especially if it is intended to generalize the conclusions drawn from site specific studies.

We investigated 17 abandoned Adélie penguin (Pygoscelis adeliae) colonies in the Windmill Islands, East Antarctica, in summer 2002/03. Forty radiocarbon dates on penguin bones and eggshells from 13 of these sites indicate a near continuous occupation by breeding penguins in this region for over 9000 years. These dates refine the recent geological record in this region and indicate that deglaciation of the northern islands occurred much earlier than previously suggested. Dietary remains from these sites include at least 23 taxa of cephalopods and teleost fish. Quantification of these remains indicates significant fluctuations in the relative abundance of two of the more common major prey taxa. The Antarctic silverfish (Pleuragramma antarcticum Boulenger) was the most common teleost prey during all time periods represented by the ages of the sites, but preservational factors may explain a gradual decrease in the remains of this species in increasingly older sites. The most common cephalopod in the sediments was the squid, Psychroteuthis glacialis Thiele, which occurred in low numbers in most sites except one (Site 75). An unusually high number of squid beaks preserved in Site 75, dating to approximately 5700–6100 cal. yr BP, does not correlate with a decrease in fish prey at that time. The high number of abandoned penguin colonies (> 200) in the Windmill Islands may be due to population cycles in the past in association with low nest-site fidelity and movement by breeding penguins to new sites within this region.

Deception Island is a young, active volcano located in the south-western part of Bransfield Strait, between the Antarctic Peninsula and the South Shetland archipelago. New gravity and magnetic data, from a marine geophysical cruise (DECVOL-99), were analysed. Forty-eight survey lines were processed and mapped around Deception Island to obtain Bouguer and magnetic anomaly maps. These maps show well- defined groups of gravity and magnetic anomalies, as well as their gradients. To constrain the upper crustal structure, we have performed 2+1/2D forward modelling on three profiles perpendicular to the main anomalies of the area, and taking into account previously published seismic information. From the gravity and magnetic models, two types of crust were identified. These were interpreted as continental crust (located north of Deception Island) and more basic crust (south of Deception Island). The transition between these crustal types is evident in the Bouguer anomaly map as a high gradient area trending NE–SW. Both magnetic and gravity data show a wide minimum at the eastern part of Deception Island, which suggests a very low bulk susceptibility and low density intrusive body. With historical recorded eruptions and thermal and fumarolic fields, we interpret this anomaly as a partially melted intrusive body. Its top has been estimated to be at 1.7 km depth using Euler deconvolution techniques.

Astronomers have always sought the very best locations for their telescopes. From observatories in city centres, astronomers moved first to nearby mountain tops, then to remote sites in distant countries, to aircraft, and into space. In the past decade we have come to realize that the best astronomical observing conditions on the surface of the earth are to be found on the Antarctic plateau. The combination of high altitude, low temperature, low absolute humidity, low wind and extremely stable atmosphere offers astronomers gains in sensitivity and measurement precision that can exceed two orders of magnitude over even the best temperate sites. In addition, spectral windows are opened up – particularly in the far-infrared and terahertz regions – that are otherwise only accessible from high-flying aircraft or from space. Established and highly successful telescopes at the South Pole are soon to be joined by a new generation of facilities at Concordia Station, including large telescopes and interferometers. It has even been suggested that the largest optical telescopes currently proposed, with diameters of up to 100 m, might achieve their science goals at a lower overall cost if they are built on the Antarctic plateau rather than at a temperate site. Such telescopes offer the possibility of not only detecting earth-like planets in other star systems, but also of analysing their atmospheres spectroscopically.

The concept of the International Polar Year (IPY) 2007–2008 is of an intensive burst of internationally coordinated, interdisciplinary, scientific research and observations focused on the Earth's Polar Regions. The research will address six themes organized around the environmental status of the Polar Regions and their relationship to change, the links between the poles and the rest of the globe, utilization of the unique features of the regions for science, and the human dimensions of communities in the Polar Regions. IPY will seek to exploit new technological and logistical capabilities, and make major advances in knowledge and understanding. Key objectives are to attract and develop the next generation of polar researchers and engineers, and to engage the interest and involvement of polar residents, and of schoolchildren, the general public, and decision makers, worldwide. The official observing period of IPY 2007–2008 will be from 1 March 2007 until 1 March 2009, under the international oversight of a Joint ICSU-WMO Committee.

A sediment core from Progress Lake, one of the oldest lacustrine sequences in East Antarctica, contains distinct zones dating from a previous interglacial (most likely Marine Isotope Stage 5e, c. 125–115 kyr BP) and the present interglacial (Marine Isotope Stage 1), separated by a transition zone representing when the lake became sub-glacial. Profiles of fossil pigments, determined using high performance liquid chromatography and liquid chromatography-tandem mass spectrometry, show distinct differences in the photoautotrophic community during these two interglacial periods. The first was dominated by algae and purple phototrophic bacteria, with periods of photic zone euxinia indicated by pigments from anoxygenic phototrophic bacteria. Specific chlorophyll a derivatives reveal periods when grazing pressure impacted significantly on the phytoplankton community. The virtual absence of pigments in the transition zone reflects severe restriction of photoautotrophic activity, consistent with the lake having become sub-glacial. Retreat of snow and ice in the late Holocene (3345 14C yr BP) allowed establishment of a less diverse primary producer community, restricted to algae and cyanobacteria. Grazers were severely restricted and oxidative transformation was more important than during the previous interglacial. The pigment data provide a unique and detailed insight in to the evolution of the lake ecology over an interglacial-glacial-interglacial transition and strong evidence that the Marine Isotope Stage 5e interglacial in this region of coastal East Antarctica was several degrees warmer than at present.

It is recognized that birds become disorientated at night in the presence of artificial light (Bruderer et al. 1999). Bird strikes on vessels operating in the southern oceans have long been known (Ryan 1991), but few data have been published concerning these events. In the Southern Ocean the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) stipulates that, during fishing operations, deck lighting should be kept to a minimum and be directed inboard and downward (CCAMLR 2003, measures 25-02 and 25-03). However, these measures are designed to keep birds away from fishing gear rather than prevent bird strikes. The problem of bird strikes has been recognized by several territories within the southern oceans and policies to reduce the risk of them occurring are included in several management plans (Ryan & Glass 2001, policy 5.14 and Meere 2002, section 28:1f–1g). These do not, however, address the issue of ice-lights (powerful searchlights used to discern floating ice that might go undetected by radar), which are regarded as essential navigational aids.

The ice surface of the glacier in the 7 km long valley Scharffenbergbotnen in Heimefrontfjella, Dronning Maud Land, is characterized by blue ice fields and is partly covered by supraglacial moraine complexes. The debris cover of the supraglacial moraines is generally less than 50 cm thick and rests on glacial ice, and most of the surface morphology of ridges and numerous sink holes reflects irregularities in the underlying ice. The debris consists of angular to sub-angular clasts of local bedrock. We interpret the moraines to have an entirely supraglacial history, where colluvium and pre-existing moraines were brought into Scharffenbergbotnen primarily from the south/south-west by an advancing glacier during the last ice maximum in the region. The debris cover of the supraglacial moraines extends up to 200–250 m above the present ice surface on surrounding slopes in Scharffenbergbotnen, and generally to less than 100 m above the present ice surface on slopes outside the valley. We interpret this as marking the ice surface elevation in the area during the last ice maximum (probably LGM). The deposition of supraglacial moraines in the valley at that time, and their survival in the area until the present day, indicate that a local ablation centre and probably blue ice fields were present in Scharffenbergbotnen at LGM, and has been a persistent feature since. In a wider context, we argue that supraglacial moraines constitute a hitherto unexploited resource when reconstructing the former extent of blue ice areas.

Deschampsia antarctica Desv. (Poaceae) is the only native Gramineae found in the Antarctic, where it is restricted to the Antarctic Peninsula and its offshore islands. Its ability to survive the harsh climate has attracted the interest of scientists searching for genes associated with freezing tolerance (Alberdi et al. 2002). For continuing research purposes it would be better if plants did not have to be collected from the field, but could be propagated effectively to provide the necessary experimental material D. antarctica normally reproduces both by seed produced by self-fertilization and also vegetatively from tillers (Holderegger et al. 2003). Vegetative propagation is slow and unable to generate enough plant material for laboratory requirements. This difficulty prompted us to develop a rapid micro-propagation method using tissue-culture methods for the production of large numbers of plants in relatively short periods.

During fieldwork of the 1998–99 and 1999–2000 Chinese National Antarctic Research Expedition (CHINARE), three different kinds of Cenozoic sedimentary record were found in the Grove Mountains, which are in East Antarctica about 450km inland of Prydz Bay. These consist of (1) glaciogenic sedimentary erratics found in the moraine banks in the central area of Grove Mountains, which can be subdivided into four types according to different degrees of lithification as well as differences in inner structure and include in-situ diamicts; (2) palaeosols found in several small depressions in the southern slope of the Mount Harding; and (3) different kinds of glacial moraine floating on the surface of blue ice or around the foot of some nunataks. Preliminary results suggest that the in situ glaciogenic sediments were formed in the ice-sheet frontal area by the interaction of glacial movement and ice sheet melt water under climatic conditions warmer than today.

We have sequenced the 18S–26S nuclear ribosomal DNA ITS region from the genome of nine different moss species from the Ross Sea region of Antarctica. This relatively quick and simple technique enables these species to be readily distinguished, facilitating their taxonomic identification. Only a single moss shoot is required, and for identification of these bryophytes it is only necessary to determine a few hundred nucleotides of the DNA sequence in a single sequencing reaction. Several previously unidentified Antarctic moss specimens were readily characterized by comparison with ITS sequences of known moss species. The relationships between species and locations previously detected by the RAPD (Random Amplified Polymorphic DNA) technique were confirmed by DNA sequencing, demonstrating that the two techniques can be complementary for molecular analysis of the ecology of mosses in Antarctica.