List of Strains

Description of holdings of 2 algal strains from Waller Creek in the ACUF collectionWaller Creek Working Grou

Cyanidiophyceae in Iceland: Plastid rbcL gene elucidates origin and dispersal of extremophilic Galdieria sulphuraria and G. maxima (Galdieriaceae, Rhodophyta)

The Cyanidiophyceae are a group of unicellular organisms that diverged from ancestral red algae around 1.3 billion years ago. Present-day species are restricted to hot springs and geothermal habitats from around the world. Because of discontinuous geothermal environments, the distribution patterns and dispersal modes of the cyanidiophycean species are poorly understood. Iceland is the third largest island in the Atlantic Ocean and has intense underground volcanic activity that generates broad hydrothermal areas with different ecological conditions that are excellent for thermoacidophilic microfloral development. We analyzed populations to address the Icelandic cyanidiophycean biodiversity and dispersal. A global rbcL phylogeny showed two main populations inhabiting Iceland, Galdieria sulphuraria and G. maxima. Their areas of distribution are not completely superimposed because they coexisted only in New Zealand, Kamchatka (Russia), Japan, and Iceland. Because of the strong monophyly of Icelandic species with Japanese and Russian species, we hypothesized an origin and dispersion of Icelandic G. suphuraria and G. maxima from northeastern Asia. On the basis of network analysis of rbcL haplotypes, it is likely that the southwestern region of Iceland is the diversity center of both G. sulphuraria and G. maxima

La météorisation des roches volcaniques dans un milieu périglaciaire humide : l'Islande du Sud

cet article traite de la variabilité de l'efficacité des processus de météorisation agissant sur les roches volcaniques. En Islande du Sud, dans un milieu périglaciaire particulièrement humide et donc favorableà la gélifraction, nous montrerons l'importance des paramètres lithologiques dans la mise en œuvred'une dégradation typiquement « périglaciaire » ou, au contraire, dans l'expression de processus non spécifiques et ubiquistes. Cet article est, principalement, une synthèse de travaux précédemment publiés (notamment dans Environnements périglaciaires), complétés par des observations inédites

Swimmer's itch in Landmannalaugar, Iceland

Hægt er að lesa greinina í heild sinni með því að smella á hlekkinn View/OpenSwimmer's itch (SI) or human cercarial dermatitis is caused by free-swimming larvae of bird parasites of the family Schistosomatidae (Trematoda) which have penetrated thorough the skin. Sometimes, mainly during first infections, the larvae do not cause any symptoms but if trapped by the immune system of the host each larva causes a maculopapular eruption. So far, five bird schistosome species have been reported in Iceland. Cercariae are shed by the freshwater snail Radix peregra but adults live in anseriform birds; one nasal Trichobilharzia species occurs in the nasal cavity of mallards, two visceral species have been found in veins of whooper swans and a visceral species has been found in greylag goose and in mallards, respectively. Experiments have shown that developing schistosomulae are able to survive for days or even weeks in mammals. Long term pathologic effects on the host are unknown. During the second half of August 2003 thousands of bathers got SI in a slowly streaming brook with geothermally heated groundwater in Landmannalaugar, the most frequently visited area in the interior of Iceland. The number of cercariae in the water and SI cases decreased until October but still in December and in late winter 2004 SI cases were reported. In August 2004 SI again started in the area but the density of cercariae in the water seemed to be less than in the previous year. The prevalence of snails shedding Trichobilharzia cercariae on the bathing site never exceeded 1%. The rapid increase of cercariae in the water by the middle of August in 2003 and 2004 were caused by a breeding mallard female and its ducklings which were raised on the bathing site during summer. All the ducklings had nasal- and visceral Trichobilharzia infections which they must have acquired soon after hatching. Three weeks later the adult worms could have started egg-laying. Consequently, emerging miracidia infected the snails which finally started shedding the cercariae by middle of August in 2003 and 2004. In future years this rapid increase of cercariae could be avoided if ducklings are not allowed to have access to the bathing site and the adjacent brook. Retrospective enquiries suggest that some visitors have occasionally got SI after bathing in the brook in preceding decades. Low number of papules, however, indicates a low density of cercariae in the water

Cryptic dispersal of Cyanidiophytina (Rhodophyta) in non-acidic environments from Turkey

Cyanidiophytina are a group of polyextremophilic red algae with a worldwide, but discontinuous colonization. They are restricted to widely dispersed hot springs, geothermal habitats, and also some human-altered environments. Cyanidiophytina are predominant where pH is prohibitive for the majority of eukaryotes (pH 0.5-3). Turkey is characterized by areas rich in volcanic activity separated by non-volcanic areas. Here we show that Cyanidiophycean populations are present in thermal baths located around Turkey on neutral/alkaline soils. All known genera and species within Cyanidiophytina were detected in Turkey, including Galdieria phlegrea, recorded up to now only in Italian Phlegrean Fields. By phylogenetic analyses, Turkish G. sulphuraria strains are monophyletic with Italian and Icelandic strains, and with Russian G. daedala strains. G. maxima from Turkey clustered with Icelandic, Kamchatka, and Japanese populations. The discovery of Cyanidiophytina in non-acidic Turkish soils raises new questions about the ecological boundaries of these extremophilic algae. This aids in the understanding of the dispersal abilities and distribution patterns of this ecologically and evolutionarily interesting group of algae

Exploring the Land of Fire and Ice: Iceland Through the Eyes of a Newman Explorer

Ganesh Chelluboyina, PhD candidate in the Energy, Environmental, and Chemical Engineering Department at the McKelvey School of Engineering, explored the glaciers, wildlife, and fjords of Iceland, to see how they are changing amidst climate change.https://openscholarship.wustl.edu/next_posters/1004/thumbnail.jp

The petrology and chemistry of the Setberg volcanic region and of the intermediate and acid rocks of Iceland

The tertiary to Mid-Quaternary Setberg volcano in western Iceland consists of two centres. The northern, Centre 1 is tholeiitic and defined by cone sheets, a caldera and a gabbro intrusion. The southern, Centre 2 is chemically transitional between a tholeiitic and an alkalic basalt series, and contains a cone sheet swarm, gabbroic ring features and a major granophyric cone sheet. Each centre can be related to a minor magmachamber at a depth of 2-3 km. General hydrothermal alteration around both centres has resulted in aureoles of epidotization and the development of greenstones, containing garnet in the central areas. Late-Quaternary volcanism in the Setberg area has produced an alkalic basalt succession, ranging from alkalic olivine baalts to benmoreites. This activity is related to the E-W Snaefellsnes volcanic zone and its causes are explained in terms of Icelandic plate tectonics. The tholeiitic seies of centre 1, form a differentiated sequence from olivine tholeiites to rhyolites, contaning a Ca-poor pyroxene and augite in the basic and intermediate rocks, and a large compositional interval devoid of olivine. Plagioclase is the sole feldspar phase. The transistional series of Centre 2 is olivine-bearing throughout, with augite and rare phenocrysts of orthopyroxene in the basalts. Two lineages of differentiated rocks of this series are typified either by iron-enrichment (to icelandites) or by alkali enrichment (to rhyodacites and alkalic-rhyolites). The latter contains anorthoclase and potassic oligoclase or sanidine, as well as sodic pyroxene. Rocks of the alkalic series are olivine and pyroxene-bearing, with anorthoclase appearing in the benmoreites, while phlogopite and hornblende have been found in some of the lavas. Apatite occurs as a phenocryst in members of both the transitional and alkalic series. The origin of the transitional basalt magma is discussed according to two hypotheses. Its formation is accounted for by solidification from above in a magma reservoir of great vertical dimensions, leading, to confinement of the magma to depths where orthopyroxene replaces olivine on the liquidus, resulting in a trend towards undersaturation. The chemistry of the Late-Quaternary alkalic basalts of Setberg and Snaefeilsnes is related to magma generation at greater depths than in the case of the tholeiitic basalts of the Icelandic central volcanic zone. The volume, bimodal distribution and diversity of acid and intermediate magmas in Iceland are discussed. The high proportion of acid to basic volcanic rocks in eastern Iceland is contrasted with 3-4% in the rest of the country. Two types of acid centres are identified: centres of Thingmuli type, where tholeiitic basalts are associated with low-alkalic rhyolites; and alkalic centres, containing comendites, quartz- trachytes, alkalic-rhyolites and associated alkalic basalts or transitional basalts. Peralkaline acid rocks are identified and described from Iceland for the first time. Their genesis is discussed and related to fractionation from alkalic-rhyolites and trachytes by the "plagioclase effect". No evidence has been unearthed in this study which contravenes the hypothesis that the Icelandic acid rocks are a product of fractionation from basic magma

Оцінка ресурсного потенціалу активного туризму Ісландії

Робота публікується згідно наказу Ректора НАУ від 27.05.2021 р. №311/од "Про розміщення кваліфікаційних робіт здобувачів вищої освіти в репозиторії університету" . Керівник проекту: д. геогр. н., проф. Колотуха Олександр ВасильовичДипломне дослідження присвячено розкриттю особливостей ресурсного потенціалу та перспектив розвитку активного туризму в Ісландії. В межах дипломної роботи визначено сутність активного туризму та його значення для регіонального розвитку; вивчено світовий досвід організації активного туризму, а саме ресурси та напрямки. Дана загальна характеристика Ісландії, виявлено особливості туристичної індустрії та ресурсного потенціалу країни, розкрито головні осередки інфраструктури активного туризму. Визначено проблемні аспекти розвитку туризму в Ісландії та напрями популяризації активного туризму. Розроблено активний тур до Ісландії