The purpose of the study was to estimate in 2012 range and degree of soil contamination due to local diesel fuel leakage spills that occurred in 1980 and from any subsequent activities in the vicinity of the scientific Polish Polar Station in Hornsund, Svalbard. The area of the study covered the immediate vicinity of station buildings including areas of the 1980’s fuel barrel storage depot and location of current fuel tanks. Results of the study were compared with a similar study performed in 1980. As of 2012, areas potentially contaminated covered 0.9 ha, which was a 50% decrease compared to 1980. The area contaminated with total petroleum hydrocarbons was extremely localized. Spread of petroleum hydrocarbons from 1980’s source of pollution investigated 32 years later showed that petroleum derived products were environmentally mobile. Concentrations of total petroleum hydrocarbons in surface soils of the unsaturated active layer above the permafrost decreased significantly mostly due to surface runoff and dispersion through ephemeral drainages. Concentrations of total petroleum hydrocarbons increased with depth through time in sandy soils on the flat area where the largest 1980’s fuel barrel depot was located.
Snowmelt is a very important component of freshwater resources in the polar environment. Seasonal fluctuations in the water supply to glacial drainage systems influence glacier dynamics and indirectly affect water circulation and stratification in fjords. Here, we present spatial distribution of the meltwater production from the snow cover on Hansbreen in southern Spitsbergen. We estimated the volume of freshwater coming from snow deposited over this glacier. As a case study, we used 2014 being one of the warmest season in the 21st century. The depth of snow cover was measured using a high frequency Ground Penetrating Radar close to the maximum stage of accumulation. Simultaneously, a series of studies were conducted to analyse the structure of the snowpack and its physical properties in three snow pits in different glacier elevation zones. These data were combined to construct a snow density model for the entire glacier, which together with snow depth distribution represents essential parameters to estimate glacier winter mass balance. A temperature index model was used to calculate snow ablation, applying an average temperature lapse rate and surface elevation changes. Applying variable with altitude degree day factor, we estimated an average daily rate of ablation between 0.023 m d-1 °C-1 (for the ablation zone) and 0.027 m d-1 °C-1 (in accumulation zone). This melting rate was further validated by direct ablation data at reference sites on the glacier. An average daily water production by snowmelt in 2014 ablation season was 0.0065 m w.e. (water equivalent) and 41.52·106 m3 of freshwater in total. This ablation concerned 85.5% of the total water accumulated during winter in snow cover. Extreme daily melting exceeded 0.020 m w.e. in June and September 2014 with a maximum on 6th July 2014 (0.027 m w.e.). The snow cover has completely disappeared at the end of ablation season on 75.8% of the surface of Hansbreen.
The objective of the study was to determine multi-annual changes and variability of occurrence of cold spells in summer and warm spells in winter on Spitsbergen in the period 1976–2016, and circulation conditions of their occurrence. Cold days in summer were defined as days with mean daily air temperature lower than temperature corresponding to the 10th percentile from daily temperature, and warm days in winter as days with mean daily air temperature exceeding the 90th percentile from daily air temperature. The research showed a statistically significant increase in mean air temperature, the rate of which in winter was more than four times higher than in summer. The observed warming translated into a decrease in the number of cold days in summer (-2.5 days/10 years in Svalbard Lufthavn and -1.3 days/10 years in Ny-Ålesund) and an increase in the number of warm days in winter (2.7 days/10 years in Svalbard Lufthavn and 2.4 days/10 years in Ny-Ålesund), and warm and cold spells related to the frequency of such days. The rate of the changes was higher in Svalbard Lufthavn than in Ny-Ålesund. The occurrence of cold days and cold spells was particularly related to the advection of air masses from the north-western sector. The occurrence of warm days and warm spells was related to the advection of air masses from the south-west.
This paper presents a comparative study on the anatomy of the Antarctic hairgrass (Deschampsia antarctica É. Desv.) from natural populations of two distant maritime Antarctic regions: the Argentine Islands (Antarctic Peninsula region) and the Point Thomas oasis (King George Island, South Shetland Islands). Comparison of D. antarctica plants from natural populations of Argentine Islands region and plants originated from seeds of these populations cultivated in vitro also was made. Additionally anatomical features of Deschampsia antarctica were compared with ones for D. caespitosa. The results of our study do not provide enough evidence to assert more pronounced xerophytic anatomical features in D. antarctica plants from more harsh conditions of Argentine Islands region. Such features (both qualitative and quantitative) of D. antarctica mainly depend on local conditions, and not on the latitudinal or climatic gradient. In both regions it is possible to find individuals that represent different ecotypes which are adopted to open arid or more humid habitats. It has been shown that Antarctic hairgrass plants germinated from seeds and cultivated in vitro retain the qualitative anatomy features that are typical to plants from the initial natural populations. This is especially noticeable in the case of plants from Berthelot Island (BE1 study plots), which might indicate a genetic fixation and a manifested differentiation similar to DNA haplotypes or chromosomal forms. However, quantitative characteristics, in particular the epidermis parameters, are subject to changes due to the transfer to more favourable conditions. Also qualitative and quantitative difference of D. antarctica in contrast with D. caespitosa have been described. These differences could be useful for identifying these two species. Additionally the quantitative differences (such as the area of the epidermal cells and the number and size of stomata on the adaxial surface) of Alaskan D. caespitosa grown from seeds were detected in contrast to the naturally grown plants of the same species from Ushuaia.
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