Czech Polar Reports

A new Lecidea species from Dismal Island (Antarctic Peninsula, Antarctica) supported by morphological, chemical, and nrITS phylogenetic evidence

Dilara Bişgin — 2026-09-15

Antarctica remains one of the least explored regions of the world in terms of lichen diversity, and many remote localities still harbor undescribed taxa. In this study, a new saxicolous lichen species belonging to the genus Lecidea is described from Dismal Island, located in the East Antarctic Peninsula region, based on an integrative taxonomic approach combining morphological, anatomical, chemical, and nrITS phylogenetic evidence. The examined material was collected from ice-free rocky habitats and deposited in the Erciyes University Lichen Herbarium (ERCH). Morphological and anatomical observations were carried out using stereomicroscopy and light microscopy, while chemical characterization was performed using standard spot tests and thin-layer chromatography (TLC). Molecular analyses were based on the internal transcribed spacer (ITS) region of nuclear ribosomal DNA. The newly generated ITS sequence was analyzed together with 92 reference sequences retrieved from GenBank^®, and phylogenetic relationships were inferred using Bayesian analysis. The results demonstrated that the studied specimen forms a distinct and well-supported lineage within Lecidea, clearly separated from all currently sequenced congeners. Although phylogenetically closest to members of the Lecidea atrobrunnea complex and L. syncarpa, the new species differs consistently in several diagnostic characters: (1) dark brown, dull, crustose and areolate thallus, (2) small black lecideine apothecia, (3) dark brown epihymenium, an I− medulla and hymenium, an N+ red hymenial reaction, and (4) the absence of both prothallus and pycnidia. Chemically, TLC revealed (5) norstictic acid as the major secondary metabolite. The combination of these stable, non-overlapping characters supports the recognition of the taxon as a distinct species, here named Lecidea devrimii. This study highlights the still underestimated lichen diversity of Antarctica and emphasizes the importance of integrative taxonomy in resolving species boundaries within morphologically complex lichen groups.

Report of Arrhenia antarctica from James Ross Island, Antarctica

Viktor Nagy — 2026-09-15

In antarctic vegetation oases, development of mushrooms depends on moisture availability, substrate characteristics, and air/substrate temperature. In our study, we bring evidence of Arrhenia antarctica distribution at James Ross Island, as well as data on the species growth, formation of fruting bodies, for 2013/2014 austral summer season in particular. This is, to our best knowledge, first record of Arrhenia antarctica reported for James Ross Island in a research journal. Available microclimate data suggest that liquid water availability in austral summer season (January, Februray) combined with high air/moss surface temperature are the most important driving factors. However, occurence of fruting bodies is highly irregular between individual austral summer seasons. In some seasons within the 2010-2015 period, no fruiting bodies were observed at all.

An AI-based Atlantic cod detection in an Arctic fjord: Linking Atlantic water intrusions to the cod (Gadus morhua) incursions

Prabhullachandran Lakshmi Devi — 2026-09-15

The Arctic Ocean is undergoing unprecedented environmental transformation, characterized by accelerated warming, reduction in sea ice cover, and altered oceanic circulation. These shifts are facilitating the poleward migration of boreal species, a process termed ’borealization’, which is fundamentally restructuring Arctic marine ecosystems. Kongsfjorden, a high-latitude glacial fjord in Svalbard, serves as a critical natural laboratory for observing these changes due to its position at the confluence of Arctic and Atlantic water masses. Historically dominated by the endemic polar cod (Boreogadus saida), the fjord is now witnessing an increasing presence of Atlantic cod (Gadus morhua). This study, conducted under the Indian Arctic Programme, deployed a novel, non-invasive, artificial intelligence (AI)-driven optical monitoring system to document the fish community. Our results reveal a direct correlation between abundance of Atlantic cod in the inner Kongsfjorden and an intense intrusion of warm, saline Atlantic Water (AW) in late summer 2024. In contrast, cod were nearly absent during in the early summer 2023 with weaker AW influence. These findings provide direct, high-resolution evidence for the oceanographic mechanism facilitating borealization in Arctic fjords and validate a new technology for sustained, long-term ecosystem monitoring in a remote and rapidly changing polar environment. The observed ecological shift signals a potential regime change that could restructure Arctic trophic interactions.

Classification of Radar Zones on Selected Glaciers in Ny-Ålesund, Svalbard

Sagar Filipe Wankhede — 2026-09-15

Glacier facies are characteristic properties of glaciers that are an observable and mappable determinant of their health. The occurrence and distribution of facies depend upon several contributing factors such as climatic shifts, sudden events, temperature, precipitation, overall deglaciation, etc. Seasonal variations of facies in one year and annual variations across several years are effective markers of seasonal and long-term glacial evolution. Synthetic aperture radar (SAR) allows for efficient generation of seasonal data within multilayer composites which can be exploited for mapping facies. In this study, we utilized Sentinel-1 data to create seasonal composites from 2016-2023 and mapped facies of selected glaciers, in Ny-Ålesund, Svalbard. We utilized unsupervised classification to obtain facies maps in a data-centric approach. This involved modulating the number of output thematic classes across sets of 3, 5, and 7, as well as changing the spatial extent from multiple glaciers to a single glacier in the classification workflow. Thematic classification revealed mixed clusters across all years and polarizations. Our analysis suggests that seasonal variability of facies leads to mixed signals within a single pixel causing misclassification. Additionally, the spatial extent of the input data drives fluxes in thematic mapping, suggesting that changes in local and global raster statistics can limit spatial scale transferability of a mapping workflow. The present results place thematic classification of glacier facies into a practical context for future applications. Our upcoming experiments will include a longer time-series, various polarizations, and advanced information extraction methods, leading to improved understanding of the operational applications of seasonal SAR data for mapping glacier facies.

Lichens and lichenicolous fungi of Prins Karls Forland (Svalbard Archipelago)

Liudmila A. Konoreva — 2026-09-15

The paper presents data on lichens and lichenicolous fungi for Prins Karls Forland (NW of Svalbard archipelago). For the island, 283 species of lichens and 21 lichenicolous fungi have been identified to date. Seventy species of lichens and 17 lichenicolous fungi are listed for the first time for the study area, of which Arthonia epipolytropa, Gyalecta peziza, Lasiosphaeriopsis christiansenii, Porpidia rugosa, and Sclerococcum protothallinum are reported for the first time for the Svalbard archipelago. The central part of Prins Karls Forland is the most studied now (157 taxa of investigated group identified). Thus, despite its small area and hard to reach, the territory of Prins Karls Forland has a high diversity of lichens. This is mainly due to the complexity of the geological formation of the territory and the high diversity of rocks. We might expect to find species here that are also typical of more southern Arctic regions considering the geographical location Prins Karls Forland in the western part of the Svalbard archipelago and the influence of the warm Gulf Stream on local microclimate. However, the island’s insular position, small area, and strong elongation from north to south, in the absence of deeply incised bays, result in the harsh influence of climatic conditions and, as a result, the wide distribution of species characteristic of the high-latitude Arctic and high-mountain regions.

Effect of mechanical transformation on oligotrophic peat at the Mukhrino Carbon Supersite (Khanty-Mansiysk Autonomous Region - Yugra, Russia)

Evgeny V. Abakumov — 2026-09-15

The impact of human activity on the peat deposit at the Mukhrino carbon supersite (Khanty-Mansiysk Autonomous Okrug – Yugra) was investigated using field electrophysical methods and laboratory analysis. Vertical electrical sounding and sampling of peat cores were carried out at two sites within the raised bog: a background site and a disturbed site (a geodetic profile cut more than 30 years ago). The peat macrofossil, moisture content, density, ash content, degree of humification, elemental composition (C, H, N), pH, and electrical conductivity of aqueous extracts were determined. Anthropogenic impact led to a slight alteration of the physical properties in the top 50 cm of the deposit: a decrease in moisture content, an increase in peat density, and an increase in the degree of peat decomposition. Below 100 cm, differences between sites are leveled out – physical parameters are determined exclusively by macrofossil composition. Vertical electrical sounding data showed low sensitivity to deposit stratification. No direct correlation was found between the physicochemical properties of the peat and the results of electrical sounding. The application of a range of methods made it possible to diagnose certain changes in the disturbed ecosystem decades after the disturbance, in particular the C/N ratio (the most sensitive indicator of long-term disturbance), which confirms the need to take anthropogenic history into account when monitoring carbon cycles at peatland sites.

Enzymatic activity of cryoconites from glaciers and high-altitude glacial soils in the Central Caucasus

Rustam Tembotov — 2026-09-15

Nowadays, in light of research into glacial cryoconites and glacial soils has become particularly relevant due to ongoing global warming and the accelerated deglaciation of high-altitude glaciers. This study presents the research into enzyme activity in cryoconites from the Maly Azau Glacier and in glacial soils of the Central Caucasus. It was shown that the enzymes studied in the cryoconites exhibited virtually no activity, with the exception of a sample taken from a cryoconite cup, in which very weak invertase activity (1.71 mg glucose / (g day)) and weak phosphatase activity (8.62 mg TPF / (10 g day). Vertical distribution of enzyme activity in the studied glacial soils indicated a decrease in the activity of all studied enzymes (dehydrogenase, catalase, invertase, phosphatase) down the profile. In the surface layer of the studied soils, redox enzymes exhibited relatively low activity. Thus, catalase (CAT) activity ranges from 0.50 to 3.63 ml O₂/ (g min)), and dehydrogenase activity from 0.07 to 1.52 mg TPF / (10 g day). In contrast to oxidases, hydrolytic enzymes exhibit high and very high activity, ranging from 27.98 to 81.94 mg glucose / (g day) for invertase and from 93.16 to 167.43 mg P₂O₅/ (100 g h) for phosphatase. The results indicated that despite the adverse and extreme climatic conditions, biochemical processes occur within glacial cryoconites. Furthermore, as deglaciation continues, cryoconites-whether washed away or left behind following glacial retreat-may influence soil formation processes in areas newly freed from ice. Our research has confirmed that biological processes are actively taking place in high-altitude soils and as the climate warms and glaciers retreat, areas adjacent to glaciers in mountainous regions, located above 2.000 m a. s. l., can be used for agriculture.

Growth promoting bacterium Mokoshia rubra isolated from Antarctic soil stimulates growth and physiological parameters of Arabidopsis thaliana cultivated in lunar regolith analog

Davide Giordano — 2026-09-15

With the planning, preparation, and execution of future long-term lunar missions, there is a growing need to develop methods that enable sustainable plant cultivation in lunar regolith, as future lunar greenhouses will require reliable and safe cultivation technologies. Over the past two decades, research has focused on the comprehensive evaluation of lunar regolith as a potential plant growth substrate and on strategies to improve its properties. These studies have investigated the addition of nutrients and organic amendments, as well as the application of autotrophic and heterotrophic microorganisms, particularly plant growth-promoting bacteria. The present study evaluated the effects of three amendments to a lunar regolith analogue: (1) Hoagland nutrient solution, (2) biochar, and (3) the plant growth-promoting bacterium Mokoshia rubra. Their effects on photosynthetic performance, growth, and physiological parameters of Arabidopsis thaliana were investigated. Hoagland nutrient solution and M. rubra inoculation positively affected the majority of chlorophyll fluorescence parameters related to PSII function and efficiency.

Ratio of different bacterial genera in oral biofilm in polar researchers during an Antarctic summer-season expedition 2026 to James Ross Island

Julie Bartáková — 2026-09-15

Short- and long-term stays in Antarctica may induce microbiome changes in oral cavity. In our study, pre- and post-Antarctic expedition oral microbiome were analysed in the participants of Czech Antarctic expedition 2026. Saliva samples were taken from the expedition members before (Day 0, January 16^th, 2026), during, and after (Day 62, March 20^th, 2026) the Czech Antarctic Expedition to Mendel station, James Ross, Island. Within the expedition time, the samples were taken on Day 34 (February 19^th, 2026) and Day 47 (March 5^th, 2026). The objective of this study was to investigate whether inducing stress conditions occurring during the Antarctic mission would affect oral microbiome composition. The results suggest that the ratio of common bacteria of oral microbiome, namely share of Streptococcus genus to other genera, decreased during the expedition time. After the return of the expedition staff to the Czech Republic, the composition of the oral microbiome shifted back to pre-expedition status. The ratio of Streptococcus genus to other bacterial strains increased again.

Spatio-temporal variability of soil surface temperature influence on Antarctic hairgrass populations adaptation. 2. Effects of fluctuations in positive temperature acumulation on changes in biological characteristics

Natalia Miryuta — 2026-09-15

Given existing uncertainties in the understanding the role of temperature in shaping the adaptation of Deschampsia antarctica populations, this study investigates the impact of soil surface positive (above-zero) temperature accumulation spactial differences on biological characteristics spactial differences. The research focuses on the complex adaptability index (I^qk_i) and complex temperature influence index I^Tk_i and last one contributions to I^qk_i for eleven Deschampsia antarctica populations on Galindez Island (Argentine Islands, maritime Antarctica) over seven consecutive Antarctic summer seasons (2017/18 – 2023/24).