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A review of scientific research trends within ASPA No. 126 Byers Peninsula, South Shetland Islands, Antarctica

Abstract Byers Peninsula, Livingston Island, was one of the first sites in Antarctica designated for environmental conservation and scientific protection. Research on Byers Peninsula has been predominantly international, with 88 indexed publications (93% of them published during last 20 years) from 209 authors affiliated to 110 institutions from 22 nations, all of which are signatories to the Antarctic Treaty. Palaeontological research represented 20% of the published articles. The variety of freshwater bodies within the area has made Byers Peninsula a reference site for limnological studies (24% of papers). The site also contains numerous outcrops and periglacial features relevant to geology, stratigraphy and geomorphology (29%). Terrestrial biodiversity is extraordinarily high for lichens, bryophytes and invertebrates (15% of articles). Only 5% of the publications concern research on human activities, including both archaeology and impact monitoring. Glaciology, meteorology and climatology studies represent only 7% of papers. This work highlights the international and multidisciplinary nature of science conducted on Byers Peninsula in order to promote international cooperation and to provide information relevant for environmental management and conservation.

Trampling on maritime Antarctica: can soil ecosystems be effectively protected through existing codes of conduct?

Soil trampling is one of the most obvious direct negative human impacts in Antarctica. Through a range of experiments and field studies based on quantitative physical (soil penetration resistance) and biological (collembolan abundance) indicators, we evaluate the current codes of conduct relating to the protection of Antarctic soils from the consequences of pedestrian impacts. These guidelines include using, where available, established paths that cross vegetation-free soils. However, the effectiveness of this strategy is highly dependent on context. Limited intensity use—below 100 foot passes per year—produces small changes at the soil surface that can recover relatively rapidly, suggesting that the dispersal of activity across wider corridors may be the most appropriate option. However, for paths with a higher use level and those located in steep-sloped sites, it is desirable to define a single track, following stony or bouldery surfaces wherever possible, to keep the disturbed area to a minimum. It is clear that both environmental conditions and expected use levels must be taken into account in determining when and where it is more appropriate to concentrate or disperse human activities. Even though they may have performed satisfactorily to date, the increasing pressure in terms of numbers of visits for certain sites may make it necessary to revise existing codes of conduct.

Rapid denudation processes in cryptogamic communities from Maritime Antarctica subjected to human trampling

Abstract This study explores the impact of human trampling on moss and lichen dominated communities of Maritime Antarctica. A simulation of trampling was performed on previously unaffected plots of different terricolous cryptogamic assemblages at Byers Peninsula, Livingston Island. The communities studied were: 1) a uniform moss carpet, 2) a heterogeneous moss assemblage composed of hummocks and turfs, and 3) a fellfield lichen community. All communities analysed were extremely sensitive but different denudation processes were observed. None of the plots maintained 50% of initial coverage after 200 pedestrian transits. Even very low trampling intensity resulted in disturbance at all plots. Sensitivities of the different communities were identified in order to formulate recommendations for minimizing the trampling impacts. In our study the lichen dominated community on dry exposed soils exhibited the lowest resistance to trampling. For moss communities, lower resistance was found in peat soils with higher water content and biomass. With the current trend of increasing human presence in Antarctica, we predict that the cumulative impacts of trampling over future decades will adversely affect all types of moss and lichen communities.

Anthropogenic and biogenic hydrocarbons in soils and vegetation from the South Shetland Islands (Antarctica)

Two Antarctic expeditions (in 2009 and 2011) were carried out to assess the local and remote anthropogenic sources of aliphatic and aromatic hydrocarbons, as well as potential biogenic hydrocarbons. Polycyclic aromatic hydrocarbons (PAHs), n-alkanes, biomarkers such as phytane (Ph) and pristane (Pr), and the aliphatic unresolved complex mixture (UCM), were analysed in soil and vegetation samples collected at Deception, Livingston, Barrientos and Penguin Islands (South Shetland Islands, Antarctica). Overall, the patterns of n-alkanes in lichens, mosses and grass were dominated by odd-over-even carbon number alkanes. Mosses and vascular plants showed high abundances of n-C21 to n-C35, while lichens also showed high abundances of n-C17 and n-C19. The lipid content was an important factor controlling the concentrations of n-alkanes in Antarctic vegetation (r(2)=0.28-0.53, p-level<0.05). n-C12 to n-C35 n-alkanes were analysed in soils with a predominance of odd C number n-alkanes (n-C25, n-C27, n-C29, and n-C31), especially in the background soils not influenced by anthropogenic sources. The large values for the carbon predominance index (CPI) and the correlations between odd alkanes and some PAHs suggest the potential biogenic sources of these hydrocarbons in Antarctica. Unresolved complex mixture and CPI values ~1 detected at soils collected at intertidal areas and within the perimeter of Juan Carlos research station, further supported the evidence that even a small settlement (20 persons during the austral summer) can affect the loading of aliphatic and aromatic hydrocarbons in nearby soils. Nevertheless, the assessment of Pr/n-C17 and Ph/n-C18 ratios showed that hydrocarbon degradation is occurring in these soils.

Trampling the Antarctic: Consequences of Pedestrian Traffic on Antarctic Soils

Antarctic soils provide habitat for fauna and flora which are regionally important and, in some cases, include endemic representatives. Thus, protection of this component of the ecosystem should be a priority. In this chapter, our focus is on the vulnerability of Antarctic soils to foot traffic (heretofore referred to as trampling) and possible future scenarios with regards to the conservation of Antarctic soils. We begin by briefly describing the principal abiotic and biotic features of Antarctic soils, and reviewing the limited studies that have examined the consequences of trampling. We then examine a range of drivers of change that could play a decisive role in the future conservation of Antarctic soils, such as climate change, human pressure and species introduction. Taking into consideration the current legal and management measures for Antarctic soils conservation, we propose two possible future scenarios assuming different management models: a Business-As-Usual scenario and a conservation-focused situation. The chapter ends with a small reflection centered on the difficulties in achieving a conservation-focused future, and the need to consider whether conservation of soil against trampling should be a priority on the agenda of the Antarctic Treaty nations and the international scientific community.

Assessing environmental conditions of Antarctic footpaths to support management decisions.

Thousands of tourists visit certain Antarctic sites each year, generating a wide variety of environmental impacts. Scientific knowledge of human activities and their impacts can help in the effective design of management measures and impact mitigation. We present a case study from Barrientos Island in which a management measure was originally put in place with the goal of minimizing environmental impacts but resulted in new undesired impacts. Two alternative footpaths used by tourist groups were compared. Both affected extensive moss carpets that cover the middle part of the island and that are very vulnerable to trampling. The first path has been used by tourists and scientists since over a decade and is a marked route that is clearly visible. The second one was created more recently. Several physical and biological indicators were measured in order to assess the environmental conditions for both paths. Some physical variables related to human impact were lower for the first path (e.g. soil penetration resistance and secondary treads), while other biochemical and microbiological variables were higher for the second path (e.g. β-glucosidase and phosphatase activities, soil respiration). Moss communities located along the new path were also more diverse and sensitive to trampling. Soil biota (Collembola) was also more abundant and richer. These data indicate that the decision to adopt the second path did not lead to the reduction of environmental impacts as this path runs over a more vulnerable area with more outstanding biological features (e.g. microbiota activity, flora and soil fauna diversity). In addition, the adoption of a new route effectively doubles the human footprint on the island. We propose using only the original path that is less vulnerable to the impacts of trampling. Finally from this process, we identify several key issues that may be taken into account when carrying out impact assessment and environmental management decision-making in the Antarctic area.

Analysis of published scientific research from Deception Island, South Shetland Islands

Abstract The aim of this study was to develop a methodology to assess the degree of multidisciplinarity and international co-operation between scientists working on Deception Island, using techniques based on social network analysis. A database was built of the scientific output, as represented by published articles, on Deception Island between 1964–2012. From the 173 published articles, the main topics, the temporal trends, the profile of the principal journals, and the contributions made by each country, research institution and scientist were obtained. The data presented show a significant role played by four of the six nations belonging to the Deception Island Management Group. However, collaborations between researchers in different fields was unusual and co-authoring by researchers from different countries was relatively low. These results show that there is a need to strengthen international co-operation, a highly advisable strategy in Antarctica due to the complexity of logistics and high operational costs. Studies such as this may help to identify synergies between institutions and researchers from different nations, improving the scientific collaboration in this area of priority for conservation and management.

Historical Developments, Drivers of Change and Future Scenarios for Human Activities on Deception Island

Deception Island is an active volcano with a flooded caldera and numerous glaciers, providing a unique habitat to very rare biological assemblies. Deception Island has a long history of human activity and is currently one of the most visited locations in the Antarctic. Natural, scientific and tourism values coexist in a small area. Some activities may interfere with others and can potentially compromise the future conservation of the island and its unique values. Under the Antarctic Treaty System (ATS), regulatory mechanisms have been developed to provide different levels of protection to the island in order to minimise the inevitable environmental impacts and cumulative effects arising from existing human activities. Six Treaty parties manage Deception Island collectively as Antarctic Specially Managed Area (ASMA) No. 4 which has been identified as an exemplar of strategic environmental management. However, under the ATS the success of policies is highly dependent on the level of stakeholder acceptance. In this chapter, through a review of the environmental impacts, regulatory mechanisms, current trends and drivers for change we examine a range of possible management scenarios that combine different levels of environmental standards with varying likelihoods of stakeholder acceptance. Success of any of these policies will rely on information provided by monitoring programmes.

Soil features in rookeries of Antarctic penguins reveal sea to land biotransport of chemical pollutants

The main soil physical-chemical features, the concentrations of a set of pollutants, and the soil microbiota linked to penguin rookeries have been studied in 10 selected sites located at the South Shetland Islands and the Antarctic Peninsula (Maritime Antarctica). This study aims to test the hypothesis that biotransport by penguins increases the concentration of pollutants, especially heavy metals, in Antarctic soils, and alters its microbiota. Our results show that penguins do transport certain chemical elements and thus cause accumulation in land areas through their excreta. Overall, a higher penguin activity is associated with higher organic carbon content and with higher concentrations of certain pollutants in soils, especially cadmium, cooper and arsenic, as well as zinc and selenium. In contrast, in soils that are less affected by penguins’ faecal depositions, the concentrations of elements of geochemical origin, such as iron and cobalt, increase their relative weighted contribution, whereas the above-mentioned pollutants maintain very low levels. The concentrations of pollutants are far higher in those penguin rookeries that are more exposed to ship traffic. In addition, the soil microbiota of penguin-influenced soils was studied by molecular methods. Heavily penguin-affected soils have a massive presence of enteric bacteria, whose relative dominance can be taken as an indicator of penguin influence. Faecal bacteria are present in addition to typical soil taxa, the former becoming dominant in the microbiota of penguin-affected soils, whereas typical soil bacteria, such as Actinomycetales, co-dominate the microbiota of less affected soils. Results indicate that the continuous supply by penguin faeces, and not the selectivity by increased pollutant concentrations is the main factor shaping the soil bacterial community. Overall, massive penguin influence results in increased concentrations of certain pollutants and in a strong change in taxa dominance in the soil bacterial community.

Collembola of Barrientos Island, Antarctica: first census and assessment of environmental factors determining springtail distribution

Barrientos Island is a small islet in the South Shetland archipelago frequently visited by Antarctic tourists. Collembola were recently used in another study developed in this site to assess the environmental conditions of two paths used by visitors, showing the importance of this soil faunal community. This motivated the realization of the first comprehensive census of Collembola from Barrientos Island. Fifty-six samples were recorded over three seasons, 2011–2013, from eight different substrate types. During the last campaign, 39 soil samples were also taken to analyze different physical, chemical, biological, microbiological, and biochemical variables in order to put into relation all these environmental conditions with abundance and richness of Collembola species. A total of ten species were recorded, all of them previously cited from Antarctica. The native species Cryptopygus antarcticus antarcticus Willem (Collembola: Isotomidae) is the most abundant in the island. Two cosmopolitan species—Hypogastrura viatica (Tullberg) (Hypogastruridae) and Mesaphorura macrochaeta Rusek (Tullbergiidae)—were also identified. Many of the species on this island can be considered as eurytopic, appearing in most of the analyzed substrate types. Collembola distribution was found to be influenced by elevation and, to a lesser extent, by phosphorous content and slope. Other variables that are usually cited in the specialized literature did not significantly influence the Collembola distribution in this island. Our results show that the distribution and abundance of Collembola in Antarctic locations is not directly dependent on a single factor. The environmental characteristics of each studied site will determine what factors are driving the composition and structure of this soil community.