Czech Polar Reports最新文献_第10页

Seasonal glacier surface velocity fluctuation and contribution of the Eastern and Western Tributary Glaciers in Amery Ice Shelf, East Antarctica 东南极洲Amery冰架东部和西部支流冰川的季节性地表速度波动及其贡献

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/cpr2019-1-5

S. Jawak, Shubhang Kumar, A. J. Luis, P. Pandit, S. F. Wankhede

{"title":"Seasonal glacier surface velocity fluctuation and contribution of the Eastern and Western Tributary Glaciers in Amery Ice Shelf, East Antarctica","authors":"S. Jawak, Shubhang Kumar, A. J. Luis, P. Pandit, S. F. Wankhede","doi":"10.5817/cpr2019-1-5","DOIUrl":"https://doi.org/10.5817/cpr2019-1-5","url":null,"abstract":"Glaciers play a crucial role in the study of the climate change pattern of the Earth. Remote sensing with access to large archives of data has the ability to monitor glaciers frequently throughout the year. Therefore, remote sensing is the most beneficial tool for the study of glacier dynamics. Fed by many tributaries from different sides, the Amery Ice Shelf (AIS) is one of the largest ice shelves that drains ice from the Antarctic ice sheet into the Southern Ocean. This study focuses on the eastern and the western tributaries of the AIS. The primary objective of the study was to derive the velocity of the tributary glaciers and the secondary objective was to compare variations in their velocities between the summer and winter season. This study was carried on using the European Space Agency’s (ESA) Sentinel-1 satellite’s Synthetic Aperture Radar (SAR) data acquired from the Sentinel data portal. Offset tracking method was applied to the Ground Range Detected (GRD) product of the Sentinel-1 interferometric wide (IW) swath acquisition mode. The maximum velocity in summer was observed to be around 610 m/yr in the eastern tributary glacier meeting the ice shelf near the Pickering Nunatak, and around 345 m/yr in the Charybdis Glacier Basin from the western side. The maximum velocity in the winter was observed to be 553 m/yr in the eastern side near the Pickering Nunatak whereas 323 m/yr from the western side in the Charybdis Glacier Basin. The accuracy of the derived glacier velocities was computed using bias and root mean square (RMS) error. For the analysis, the publicly available velocity datasets were used. The accuracy based on RMS error was observed to be 85-90% for both seasons with bias values up to 25 m/yr and root mean square error values up to 30 m/yr.","PeriodicalId":37981,"journal":{"name":"Czech Polar Reports","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71342129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Permafrost and active layer research on James Ross Island: An overview 詹姆斯罗斯岛多年冻土带和活跃层研究综述

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/cpr2019-1-3

F. Hrbáček, D. Nývlt, K. Láska, M. Knazková, Barbora Kampová, Zbyněk Engel, M. Oliva, C. Mueller

{"title":"Permafrost and active layer research on James Ross Island: An overview","authors":"F. Hrbáček, D. Nývlt, K. Láska, M. Knazková, Barbora Kampová, Zbyněk Engel, M. Oliva, C. Mueller","doi":"10.5817/cpr2019-1-3","DOIUrl":"https://doi.org/10.5817/cpr2019-1-3","url":null,"abstract":"This study summarizes the current state of the active layer and permafrost research on James Ross Island. The analysis of climate parameters covers the reference period 2011–2017. The mean annual air temperature at the AWS-JGM site was -6.9°C (ranged from -3.9°C to -8.2°C). The mean annual ground temperature at the depth of 5 cm was -5.5°C (ranged from -3.3°C to -6.7°C) and it also reached -5.6°C (ranged from -4.0 to -6.8°C) at the depth of 50 cm. The mean daily ground temperature at the depth of 5 cm correlated moderately up to strongly with the air temperature depending on the season of the year. Analysis of the snow effect on the ground thermal regime confirmed a low insulating effect of snow cover when snow thickness reached up to 50 cm. A thicker snow accumulation, reaching at least 70 cm, can develop around the hyaloclastite breccia boulders where a well pronounced insulation effect on the near-surface ground thermal regime was observed. The effect of lithology on the ground physical properties and the active layer thickness was also investigated. Laboratory analysis of ground thermal properties showed variation in thermal conductivity (0.3 to 0.9 W m-1 K-1). The thickest active layer (89 cm) was observed on the Berry Hill slopes site, where the lowest thawing degree days index (321 to 382°C·day) and the highest value of thermal conductivity (0.9 W m-1 K-1) was observed. The clearest influence of lithological conditions on active layer thickness was observed on the CALM-S grid. The site comprises a sandy Holocene marine terrace and muddy sand of the Whisky Bay Formation. Surveying using a manual probe, ground penetrating radar, and an electromagnetic conductivity meter clearly showed the effect of the lithological boundary on local variability of the active layer thickness.","PeriodicalId":37981,"journal":{"name":"Czech Polar Reports","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45475103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Open top chamber microclimate may limit photosynthetic processes in Antarctic lichen: Case study from King George Island, Antarctica 开放式顶室小气候可能限制南极地衣的光合作用过程:来自南极洲乔治王岛的案例研究

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/cpr2019-1-6

A. Casanova-Katny, M. Barták, C. Gutiérrez

{"title":"Open top chamber microclimate may limit photosynthetic processes in Antarctic lichen: Case study from King George Island, Antarctica","authors":"A. Casanova-Katny, M. Barták, C. Gutiérrez","doi":"10.5817/cpr2019-1-6","DOIUrl":"https://doi.org/10.5817/cpr2019-1-6","url":null,"abstract":"Long-term manipulated warming experiments using the open top chamber (OTC) approach tend to mimick the future climate and predict the changes in photosynthesis and production of vegetation under globally changed climate. In Antarctica, several long-term experiments are carried out recently. Here we report to the lichens grown in OTCs installed at the Fildes Peninsula (King George Island). The field study compares primary photochemical processes of photosynthesis in Antarctic lichen Placopsis antarctica grown for one year in OTC and compared to outside plot (control). We measured effective quantum yield of photosystem II (ΦPSII) of green algae part of thallus in 10 min. interval for 12 days. We examined the responses of diurnal ΦPSII to PAR in relation to environmental factors through continuous 12-d-long monitoring of chlorophyll fluorescence parameters ΦPSII in particular. Daily courses of ΦPSII and photosynthetic electron transport rate (ETR) to photosynthetically active radiation (PAR) and hydration state of thallus have been assumed to reflect changes in physiological status of P. antarctica in changing Antarctic environment. The data indicate that OTC microenvironment may lead to partial limitation of photosynthetic processes in P. antarctica during austral summer season. The limitation is caused by accelerated dehydration of thallus in OTC compared to the outside generally colder control plot, and thus shortened physiologically active period of lichens in OTC.","PeriodicalId":37981,"journal":{"name":"Czech Polar Reports","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71342140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Fungal species associated with fruit and vegetables transported to the J.G. Mendel station and the influence of UV-C treatment on their fungal community 与水果和蔬菜相关的真菌物种运输到J.G.孟德尔站及UV-C处理对其真菌群落的影响

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/cpr2019-1-7

M. Laichmanová, I. Sedláček

引用次数: 1

Microclimate variability of Antarctic terrestrial ecosystems manipulated by open top chambers: Comparison of selected austral summer seasons within a decade 开顶室控制下南极陆地生态系统的小气候变率:十年来选定的南方夏季的比较

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/cpr2019-1-8

M. Barták, K. Láska, J. Hájek, P. Váczi

{"title":"Microclimate variability of Antarctic terrestrial ecosystems manipulated by open top chambers: Comparison of selected austral summer seasons within a decade","authors":"M. Barták, K. Láska, J. Hájek, P. Váczi","doi":"10.5817/cpr2019-1-8","DOIUrl":"https://doi.org/10.5817/cpr2019-1-8","url":null,"abstract":"Open top chambers (OTCs) were established in the northern part of the James Ross Island, Antarctic Peninsula, as a part of long-term program in January 2007. They were installed in two typical locations differing in vegetation cover. First group was set in a seashore ecosystem dominated by moss carpet supplemented with few lichen species. The other group was located on the top of a volcanic mesa (350 m a.s.l.) with irregular cover of lichens Usnea antarctica and Umbilicaria decussata. Temperature regimes inside and outside OTCs were continuously measured and related to year-round reference meteorological data. For majority of OTC installations, temperature increase caused by OTC was apparent in the period of September-March. Detailed analysis of chamber effect on the increase in air, surface, vegetation, and ground temperatures was done for late austral summer seasons of 2007 and 2008, and 10 years later, the seasons of 2017 and 2018. The OTC-induced temperature increase was more pronounced for mesa than seashore plot. For both locations, OTC-induced increase in temperature was highest for warm days with full sunshine and limited wind speed. On stormy days with overcast sky and high wind speed, the shift in temperature was smaller. Consequences of a long-term manipulation of Antarctic terrestrial ecosystems by OTCs for moss and lichen ecophysiology are discussed.","PeriodicalId":37981,"journal":{"name":"Czech Polar Reports","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71342316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Changes in haematological parameters during a summer expedition in Antarctica 南极夏季考察期间血液参数的变化

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/cpr2019-1-9

A. Žákovská, Olivie Zezulová

引用次数: 0

Sphaerellothecium reticulatum (Zopf) Etayo, a new lichenicolous fungusfor Antarctica Sphaellothecum reticulatum（Zopf）Etayo，一种新的南极地衣真菌

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/CPR2019-1-2

M. Halıcı, M. Barták

引用次数: 6

The effect of shock freezing on physiological properties and consequent growth of Antarctic filamentous (Stigeoclonium sp.) and coccal alga (Diplosphaera chodatii) on agar plates 冲击冷冻对南极丝状藻(Stigeoclonium sp.)和球菌藻(Diplosphaera chodatii)在琼脂平板上的生理特性和生长的影响

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Czech Polar Reports Pub Date : 2019-01-01 DOI: 10.5817/cpr2019-1-4

A. Orekhova, M. Barták, Aleyna Özkar, J. Elster

{"title":"The effect of shock freezing on physiological properties and consequent growth of Antarctic filamentous (Stigeoclonium sp.) and coccal alga (Diplosphaera chodatii) on agar plates","authors":"A. Orekhova, M. Barták, Aleyna Özkar, J. Elster","doi":"10.5817/cpr2019-1-4","DOIUrl":"https://doi.org/10.5817/cpr2019-1-4","url":null,"abstract":"In this study, we investigated the effects of shock freezing on physiological properties and consequent growth of in the Antarctic alga Stigeoclonium sp. and comparative coccal alga Diplosphaera chodatii on agar plates. Culture of algae grown in liquid medium were used to study subzero temperatures on the species resistance to shock freezing. Then, microalgae were frozen in liquid nitrogen and inoculated on BBM agar after thawing. Physiological status of algae was evaluated by chlorophyll fluorescence parameters during 28 days. The results showed that interspecific differences existed in their tolerance to shock freezing, as well as their consequent growth rate on agars. Direct effects of freezing in liquid nitrogen was demonstrated in chlorophyll fluorescence parameters recorded immediately after thawing the samples (in liquid medium). In spite of the fact that majority of cells was destroyed by shock freezing, the potential of photochemical processes in PS II (FV/FM) remained constant in D. chodatii. It may indicate high resistance of the species to freezing/thawing cycles and a capability of the surviving cells, core chlorophylls in PS II respectively, to perform photosynthetic processes related to PS II. Contrastingly, Stigeoclonium sp. showed a shock freezing-dependent decrease in FV/FM. When shock-frozen, thawed and inoculated on agar plates, the culture of D. chodatii, and Stigeoclonium sp. showed cultivation time-dependent increase in chlorophyll fluorescence parameters (FV/FM, FS).","PeriodicalId":37981,"journal":{"name":"Czech Polar Reports","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71342122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Comparative research of photosynthetic processes in selected poikilohydric organisms from Mediterranean and Central-European alpine habitats 地中海和中欧高山生境中几种淡水生物光合过程的比较研究

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Czech Polar Reports Pub Date : 2018-07-01 DOI: 10.5817/cpr2018-2-24

G. Giudici, J. Hájek, M. Barták, S. Kubešová

{"title":"Comparative research of photosynthetic processes in selected poikilohydric organisms from Mediterranean and Central-European alpine habitats","authors":"G. Giudici, J. Hájek, M. Barták, S. Kubešová","doi":"10.5817/cpr2018-2-24","DOIUrl":"https://doi.org/10.5817/cpr2018-2-24","url":null,"abstract":"Dehydration-induced decrease in photosynthetic activity was investigated in five poikilohydric autotrophs using chlorophyll fluorescence parameters recorded during controlled desiccation. For the study, two representatives of mosses from alpine zone (Rhizomnium punctatum, Rhytidiadelphus squarrosus) of the Jeseníky Mts. (Czech Republic) were used. Other two experimental species were mediterranean habitats liverwort (Pellia endiviifolia) and moss (Palustriella commutata), collected from under Woodwardia radicans canopy in the Nature Reserve Valle delle Ferriere (Italy). The last species was a liverwort (Marchantia polymorpha) collected from lowland site (Brno, Moravia, Czech Republic). We investigated the relationship between relative water content (RWC) and several chlorophyll fluorescence parameters evaluating primary photochemical processes of photosynthesis, such as effective quantum yield of photosynthetic processes in photosystem II (ΦPSII), and non-photochemical quenching (qN). With desiccation from fully wet (RWC = 100%) to dry state (RWC = 0%), ΦPSII exhibited a rapid (R. punctatum) and slow decline of ΦPSII (R. squarrosus, P. endiviifolia, M. polymorpha, and P. commutata). Shapes of dehydration-response curves were species-specific. RWC0.5, i.e. the RWC at which the sample showed half of maximum ΦPSII, reflected the species-specificity. It reached 65% in desiccation sensitive (R. punctatum), 53% and 43% in semi-tolerant (P. commutata and R. squarrosus), 24% and 18% in desiccation-tolerant species (P. endiviifolia and M. polymorpha). In all experimental species, non-photochemical quenching (qN) of absorbed light energy showed high values at RWC = 100% and a slight increase with desiccation. Steady state chlorophyll fluorescence (FS) remained high during desiccation and was not correlated with ΦPSII. ","PeriodicalId":37981,"journal":{"name":"Czech Polar Reports","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48416283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Diatoms (Bacillariophyta) associated with lichens from Ulu Peninsula (James Ross Island, NE Antarctic Peninsula) 南极半岛东北部乌鲁半岛(詹姆斯罗斯岛)与地衣相关的硅藻(硅藻门)

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Czech Polar Reports Pub Date : 2018-07-01 DOI: 10.5817/cpr2018-2-12

Hutňan Chattová, Barbora

{"title":"Diatoms (Bacillariophyta) associated with lichens from Ulu Peninsula (James Ross Island, NE Antarctic Peninsula)","authors":"Hutňan Chattová, Barbora","doi":"10.5817/cpr2018-2-12","DOIUrl":"https://doi.org/10.5817/cpr2018-2-12","url":null,"abstract":"Since 2000, the entire Antarctic diatom flora is being revised using a more fine-grained taxonomy based on a better analysis and interpretation of the morphological and molecular observations. Despite the increased diatom research and efforts, the diversity and ecology of diatoms of lichen inhabiting flora of James Ross Island weren’t studied yet. To reveal the actual diatom diversity, samples were collected during February and March 2018 from lichens on the Ulu Peninsula, James Ross Island, a 2,450 km2 large island, situated in the north-western part of the Weddell Sea, close to the northern tip of the Antarctic Peninsula. The analysis of 29 lichen samples revealed the presence of 56 diatom taxa belonging to 17 genera. The most abundant species were Luticola muticopsis, Hantzschia amphioxys f. muelleri, Pinnularia borealisvar.scalaris, Luticola aff. pusilla and Achnanthes muelleri. Biogeographically, the lichen-inhabiting diatom flora of the Ulu Peninsula is composed of cosmopolitan, Antarctic and endemic elements. The present study is the first focusing on the diversity of lichen-inhabiting diatom communities on James Ross Island, revealing the presence of a rather species rich diatom flora.","PeriodicalId":37981,"journal":{"name":"Czech Polar Reports","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42424154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5