Daniel Nývlt

Since 2006 operate on the James Ross Island near Antarctic Peninsula the Czech scientific station. Its research program is focussed on the deglaciated area in north part of iceland whose surface area represent about 170 km2 (one of the largest deglaciated area in the Antarctica). The multidisciplinary scientific program aimed at formation, present and future development of mentioned area is here under way This contribution refer about first results of climatic and glaciological investigations in mentioned area concerning on (1) UV-radiation and its impact by atmospheric factors, (2) topoclimatic conditions, (3) vegetation microclimate and its possible change and (4) response of two kind of glaciers on changed climatic conditions.

Permafrost controls geomorphic processes in ice-free areas of the Antarctic Peninsula (AP) region. Future climate trends will promote significant changes of the active layer regime and permafrost distribution, and therefore a better characterization of present-day state is needed. With this purpose, this research focuses on Ulu Peninsula (James Ross Island) and Byers Peninsula (Livingston Island), located in the area of continuous and discontinuous permafrost in the eastern and western sides of the AP, respectively. Air and ground temperatures in as low as 80 cm below surface of the ground were monitored between January and December 2014. There is a high correlation between air temperatures on both sites (r=0.74). The mean annual temperature in Ulu Peninsula was -7.9 ºC, while in Byers Peninsula was -2.6 ºC. The lower air temperatures in Ulu Peninsula are also reflected in ground temperatures, which were between 4.9 (5 cm) and 5.9 ºC (75/80 cm) lower. The maximum active layer thickn...

<p>Aeolian dune field pattern could provide a very detailed image of the influence of environmental controlling factors (wind regime, topography, sediment supply and others) to its development. Moravian Sahara dune field located in Southern Moravia, Czechia, and thus far away from the European Sand Belt (i.e. the area of major aeolian accumulations in Europe), represent a unique archive reflecting the effects of these variables. Even despite its remoteness from the Fennoscandian Ice Sheet during the Last Glacial Maximum, the permafrost occurred in Southern Moravia, and thus periglacial processes operated here. Different approaches including LiDAR DTM analysis, ground-penetration radar (GPR), and near-surface wind modelling were applied to investigate the role of the controlling factors. Two groups of differently oriented periglacial-related dunes (ENE-WSW and N-S) have been distinguished via the DTMs, suggesting a significant twist in atmospheric circulation connected with the retreat of the Fennoscandian Ice Sheet after the Last Glacial Maximum. Beside that, a strong influence of the local topography to the modification of the wind flow and the possible sediment sources were distinguished and described. Furthermore, confrontation of the reconstructed palaeowind directions with the modelled atmospheric circulation during the Weichselian and the OSL ages of aeolian sediments enabled the temporal assignment of the Moravian Sahara dune field development to the Late Pleniglacial and Late Glacial periods. Thus, our results show their applicability to the very detailed study of the influence of environmental conditions on the development of the cold-climate aeolian dune fields.</p>

<p>Antarctica with its unique conditions for soil development offers the opportunity to disclose basic soil biogeochemical processes in an environment with a low degree of ecosystem interactions. The region’s climate is divided by the mountain ridge of the Antarctic Peninsula: on the South Shetland Islands (King George Island (KGI)) in the west a maritime cold climate prevails, while James Ross Island (JRI) in the east faces the continental cold climate of a polar desert with less precipitation and distinctly more pronounced temperature variations throughout the year. In addition, the autochthonous vegetation differs; while it solely consists of cryptogams on JRI, on KGI two vascular plants (Dechampsia antarctica, Colobanthus quitensis) are endemic. This scarce vegetation patterns together with land surfaces ice-free for several millenia allows studying the complex interaction between soil organic matter (SOM) sequestration and soil structure development with respect to the varying presence and growth of vegetation.  </p> <p>The main aim of our study is to decode the mechanisms determining the fate of SOM in maritime Antarctica and to understand how the scarce vegetation drives the chemical composition and distribution of SOM within specific physical SOM fractions. Therefore, we sampled transects ranging from vegetated patches to plant-free soil surfaces. The distance to these vegetation patches was reflected in clear variations in the distribution of carbon and nitrogen and in a decrease in labile SOM constituents as revealed by <sup>13</sup>C-CPMAS NMR spectroscopy, while clay-sized mineral-associated SOM dominated the carbon storage throughout all sites. The ongoing climate change is assumed to significantly alter the vegetation distribution and thus drive the storage and composition of SOM. In the future, this will also strongly affect soil microbial activity and land-ocean transitions in Antarctica.</p>

Objective The aim of this prospective observational study was to investigate the effects of a novel Wim Hof psychophysiological training program on stress responses and hormone release in healthy participants during an Antarctic expedition. Methods All members of an Antarctic expedition were included in the study. The participants were healthy volunteers allocated to an intervention group (n = 6) and a control group (n = 7). The intervention consisted of 8 weeks of Wim Hof training. The training program comprised three integrated parts: breathing exercises, cold exposure and meditation. Psychometric measures (the Beck Depression Inventory and the Trauma Symptom Checklist-40) and neuroendocrine measures (cortisol, melatonin) were assessed pre- and post-intervention. Results The results showed that the 8-week training program significantly reduced stress responses, as indicated by a reduction in depressive symptoms. A non-significant reduction in cortisol was also observed. Conclusions These data constitute preliminary findings indicating that the Wim Hof Method may positively affect stress symptoms and adaptability of the hormonal system to respond adequately to the circadian rhythm in healthy volunteers who participated in an Antarctic expedition.

Northern European ice sheet advanced during its maximum Elsterian extent to the Central and Eastern Sudetes Mts. foreland, i.e. to the Rychleby Mts. and Zlate Hory Highlands. Glacial deposition was controlled by local morphology in this area. The following depositional environments have been identified during ongoing research in Rychleby Mts. and Zlate Hory Highlands: subglacial environment affected by subglacial morphology and lithology (cavities infill, glacitectonite), supraglacial environment of ablation moraines, terminoglacial to proglacial outwash plains, terminoglacial fans and proglacial outwash plains.

The scope of the workshop will range from a variety of abiotic factors forming polar habitats to biodiversity and ecophysiology of autotrophic constituents of polar ecosystems such as algae and cyanobacteria, lichens, mosses, higher plants. Terrestrial invertebrates and vertebrates, their biodiversity, distribution, production, stress physiology, population biology, etology are considered as workshop topics as well. Last but not least, ECOSYS 2014 wants to address human impact in polar regions, allien species, conservation issuess and measures aimed to sustain undisturbed and functioning polar ecosystems for future generations.

Klebsormidium sp. and Zygnema sp. are typical algal species forming microbiological mats in Antarctic lakes, streams and seepages of the James Ross Island (Antarctica). For physiological study focused on their photosynthesis, two strains collected at the island (Klebsormidium sp. SNOKHOUSOVA et ELSTER 2008/8, and Zygnema sp. SNOKHOUSOVA et ELSTER 2009/8) were obtained from Culture Collection of Autotrophic Organisms, Institute of Botany, Třeboň. Cultivation was carried out in liquid 3N BBM solution under constant temperature and a 12/12 h light/dark period in a FS130 phytoscope (PSI). In this study, we present the results of experiments focused on interspecific differences in photosynthesis as dependent on light, temperature, repetitive photoinhibition and osmotic stress. Light-response curves of photosynthesis: Simultaneous measurements of oxygen evolution rate (OER) and effective quantum yield of PSII (PSII yield) by an inbuilt Theta 90 (ldv) oxygen electrode and a FL-400 (PSI), fluorometer, respectively, were done at fixed above-zero temperatures. In both species, OER and yield PSII were well related throughout a range of light (0-500 micromols m-2 s-1 of photosynthetically active radiation (PAR). Photoinhibitory treatment: Using a FMT 400 photobioreactor (PSI), repetitive photoinhibition and dark recovery was studies in Klebsormidium sp. by simultaneous measurements of OER and PSII yield. The data revealed large resistance of the two species against photoinhibition, however, the courses of respiratory OER and potential PSII yield measured at dark changed with increasing number of photoinhibitory treatment. Osmotic stress: The effects of salt (NaCl) treatment on excitation energy transfer from light harvesting complexes to photosystem II (PSII) in two Antarctic algae: Klebsormidium sp. and Zygnema sp. were investigated using chlorophyll fluorescence transients (OJIPs). Short-term salt stress led to significant changes in the shape of OJIPs indicating altered functioning of PSII. With time of exposition to NaCl treatment, the fluorescence yield at the phases J, I and P declined considerably in both species.

Late Miocene to Late Pleistocene alkaline lavas in the northernmost part of the Antarctic Peninsula and its off-lying islands are the latest stage of magmatic activity that took place in response to lithospheric extension in the back-arc region of the South Shetland subduction system. The alkaline magmatism occurred much later than the main pulse of Cretaceous arc magmatism and generated basaltic extrusive rocks during several sub-aqueous/sub-glacial and sub-aerial eruption periods. The suite consists primarily of alkali olivine basalts with oceanic island basalt (OIB)-like trace element signatures, characterized by elevated highly to less incompatible element ratios compared to MORB. The samples have higher 87Sr/86Sr (0.70301–0.70365), and lower 143Nd/144Nd (0.51283–0.51294) and 176Hf/177Hf (0.28291–0.28298) than depleted MORB mantle. Their lead isotope ratios vary within a limited range with 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb ratios of 18.797–18.953, 15.577–15.634, and 38.414–3...

Diatoms are important ecological indicators in Antarctica, and paleolimnologists routinely apply transfer functions to fossil diatoms recovered from lake sediments to reconstruct past environments. However, living diatom communities may differ among the possible habitat types represented in sediment cores (both within lakes and their immediate proximity), hindering the full and accurate interpretation of fossil records. Therefore, an improved understanding of Antarctic diatom habitat preferences would substantially aid in interpreting regional paleo-material. To gain insights into habitat differences, we sampled epipelon, epilithon, Nostoc mats, lake-adjacent moss, and wet soil from > 30 lakes and ponds from Clearwater Mesa, James Ross Island, spanning a broad gradient in conductivity (a common basis for transfer functions). We found that diatom communities significantly differed between habitat types (although abundances were too low in Nostoc mats to characterize communities), with the clearest distinctions being between submerged (epipelon and epilithon) and exposed (moss and wet soil) groups. Submerged habitat types had greater abundances of attached aquatic taxa (i.e. Gomphonema spp.), while exposed habitats harboured more abundant aerophilic genera (e.g. Hantzschia, Luticola, and Pinnularia). Furthermore, only epilithon communities were significantly related to conductivity, and both epipelon and epilithon habitats showed conspicuous increases in Denticula jamesrossensis at greater conductivity values. Collectively, these results improve our knowledge of limno-terrestrial diatoms from the Maritime Antarctic Region, and further highlight the utility of incorporating knowledge of habitat preferences into (paleo)ecological research.

Clast petrology, provenance and shape data for the Middle Pleistocene glaciofluvial sand and gravel of the Mníšek member are presented and discussed. The results are compared with those for in situ weathered bedrock debris and recent fluvial sediments from the same area. The most common petrological classes are local and near granitoids, and the feldspar and quartz grains that result from their breakdown. Clast form is influenced mainly by the petrological and mineralogical properties of the material; the degree of rounding is controlled by length, energy and mode of transport and, less importantly, by resistance. These findings are at variance with those proposed by others in recent studies. The covariant plot of RA index versus C40 index is the most appropriate tool for the graphical presentation and differentiation of glaciofluvial sediments. However, a combination of this type of plot, other covariant plots and linear diagrams yielded good results for the material investigated i...

<p>Microplastics have been found in various places, including not only densely populated areas of China or Germany but also remote high-altitude places like the Himalayas or the Pyrenees. However, the remoteness of a place is not determined only by its altitude. The Outer Hebrides (Scotland), with a low population and minimum industry, are remote in terms of direct pollution. This study aims to analyse the occurrence and spatial distribution of microplastics in soils of the Outer Hebrides to discover the factors driving the abundance of microplastics and to find how much more or less are remote Scottish soils polluted with microplastics than inland soils of populated areas.</p><p>In the Isle of South Uist, 123 topsoil samples were collected along the western coastline and in four transects through the isle in the west-east direction. In total, 63 samples were analysed using an optical microscope to quantify the plastic microfibres visually using a semi-automatic algorithm. The amounts of microfibres were statistically processed, and their distribution was modelled for the entire archipelago.</p><p>More microplastics are present in inland soils with loamy soil texture, denser vegetation and denser roots (median = 36,900 microfibres/L) than in coastal soils with sandy soil texture, sparse vegetation and low root density (median = 3,580 microfibres/L). Their abundance is mainly influenced by soil texture, vegetation density, and root density.</p><p>With the south-western prevailing wind direction, we assume that most microfibres enter the island from the Atlantic Ocean, and the wind transports the microfibres inland to the east. Wind deflates the microfibres from coastal soils, and microfibres are deposited in inland soils. The inland soils are less susceptible to wind erosion, and the microfibres accumulate there.</p><p>Thus, the remoteness of the Outer Hebrides does not guarantee low microplastic pollution. Contrarily, the Hebridean soils are extensively more polluted than most so far studied sites. The level of pollution is comparable to only a few studies where the abundance of microplastics in the soils is similar, e.g. Beijing (China), Lower Rhine basin (Germany) or Coimbra (Portugal). However, these sites are much more populated and interconnected, which suggests a great contribution of microplastic pollution from Atlantic Ocean and a great magnitude of wind transport processes in the Outer Hebrides.</p>

V roce 2005 proběhly dvě terénní expedice. Hlavními cíli v této etapě byl geologický výzkum v širším okolí stavby stanice, který navazoval na předchozí, loňskou etapu a zahrnoval témata: Podrobné geologické mapování území širšího okolí budoucí stanice pro potřeby projektovaného biologického monitoringu; Studium zdrojových oblastí tillů a glacifluviálních sedimentů na ostrově James Ross ve vztahu k paleoklimatologickému a paleogeografickému vývoji oblasti; Geomorfologický výzkum kamenných ledovců, periglaciálních a paraglaciálních fenoménů na ostrově James Ross; Vývoj zalednění na ostrově James Ross, studium glaciálních a glacimarinních sedimentů terciérního i kvartérního stáří a zalednění; Paleoklimatická rekonstrukce během holocénu; Organické průmyslové polutanty - jejich koncentrace, chování a degradace v prostředí Antarktidy

UNIVERZITA KARLOVA V PRAZE PŘÍRODOVĚDECKÁ FAKULTA Katedra fyzické geografie a geoekologie Paleogeografická rekonstrukce kontinentálního zalednění Šluknovské pahorkatiny (souhrn) Palaeogeographic reconstruction of the continental glaciation in the Šluknov hilly land (summary) DANIEL NÝVLT Praha, 2008 Předložená doktorská disertační práce vznikla během autorova studia na Katedře fyzické ge- ografie a geoekologie Přírodovědecké fakulty Univerzity Karlovy a při práci v České geolo- gické službě (do roku 2002 Českém geologickém ústavu) na projektu základního geologického mapování Šluknovského výběžku a na projektu Paleogeografická, paleoklimatologická a geo- chronologická rekonstrukce kontinentálního zalednění Česka. Autor práce: Mgr. Daniel Nývlt Česká geologická služba, pobočka Brno Leitnerova 22 658 69 Brno daniel.nyvlt@geology.cz Školitel: Prof. RNDr. Jan Kalvoda, DrSc. Konzultant: Doc. RNDr. Jiří Kovanda, CSc. Úvod a vymezení práce Během posledního půlstoletí byl nashromážděno velké...

An accumulation of glacial sediments is located near Pisecna village in the depression between the Sokol Ridge and Zlate Hory Highlands NNE of Jesenik town (Eastern Sudetes). The accumulation lies at the lateral side of the mountain valley of the Běla River and fills a preglacial palaeovalley of this river. Research combining facies analysis of outcrops, ground penetrating radar survey, interpretation drilling survey, and modelling of the preglacial relief was undertaken at the site. According to the results obtained, the upper part of the sedimentary accumulation represents a coarse-grained terminoglacial glaciofluvial delta of the Gilbert type. The development of the accumulation has dominantly been driven by the preglacial morphology. Facies typical for foresets of coarse-grained deltas represented mainly by high-density flows, cohesionless debris flows, debris falls and less common low-density flows were found in the outcrops. The delta near Pisecna prograded into a lake dammed ...

In this contribution, two glaciers located on the northern part of James Ross Island (Ulu Peninsula) are studied to determine the impact of local climate changes on glacier mass balance. Whisky Glacier is a well-delimited valley glacier located mostly below the local Equilibrium line altitude (ELA). The glacier has an area of 2.3 km2 and lies in the altitude range of 215–460 m a.s.l. Davies Dome is a flat-bottom dome glacier with significant part of its surface located above the ELA and a single outlet that flows towards the SW. Field mapping and mass balance measurements were used to reveal the spatial change of glacier surfaces and to assess the annual mass balance. The maximum thickness of Davies Dome and Whisky Glacier is 85 m and 145 m respectively.

Pisecnik Hill (288 m a.s.l.) is an isolated elevation located near the Javornik Town close to the NE foothill of the main ridge of the Rychleby Mts. It has a shape of a ridge elongated in the NE–SW direction, made of compacted Miocene sands covered by Pleistocene tills and glaciofluvial sediments. Glacial sediments represent succession of subglacial sediments at the bottom followed by supraglacial sediments in a direct superposition. Subglacial sediments consist of two units - lodgement till with boulder lag on base and infill of shallow depression in subglacial lodgement till. Subglacial sediments are monotonous from petrological point of view with a clear predominance of local rocks (mainly of Gieraltow gneiss). Supraglacial sediments are better sorted and more variable from facies point of view (boulder gravel, wavy-laminated sand and cobble-boulder gravel). Supraglacial sediments consist diversified material. Clats originating from the entire vertical profile of an ice sheet mar...

Within last two decades, education of undergraduate and postgraduate students at the Masaryk University (Brno), an institution responsible for running the Czech Antarctic station J.G.Mendel and education of a new generation of Czech specialists in a variety of disciplines in Antarctic science, has been carried out in regular courses: (1) Polar Ecology, and (2) Polar Plant Biology. The two core courses have annual attendance of about 20 students each and focus a variety of topics related to Antarctic science. The course Polar Ecology covers the theoretical part of geoscientific disciplines focused on Polar regions. It includes information covering polar research in the following scientific branches: geology, geomorphology, meteorology, climatology, glaciology, hydrology and limnology. The Polar Plant Biology includes Plants in the Arctic and Antarctica, vegetation of coastal and continental Antarctica, vascular plants in polar regions, diversity of algae and cyanobacteria, mosses and...

Proglacial braided river systems in the High Arctic are very changeable during summer seasons. Hydrological regime of local streams is connected to a functioning the interaction between glaciers and atmosphere. This study summarize fluvial geomorphological summer research season of 2016 (7.7.2016 –27.8.2016). Our area of interest is located in central part of Svalbard archipelago near the Pyramiden settlement in Muninelva River catchment. The river is 6 km long and its channel belt is 50–250 m wide (Ondrackova et al., 2016). During the observation period of Muninelva River fluvial system we recognized many examples of well-developed fluvial forms changes, channel pattern evolution, channel bars downstream change, flood stages, hydrological conditions change, channel course replacement and also the end of the hydrological cycle. The changes of braided river channels are coupled with meteorological conditions, especially with temperature and precipitations. For example, the main chann...