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Sample records for adjacent antarctic areas

  1. Bacterial productivity in the Prydz Bay and its adjacent waters,Antarctic

    邱雨生; 黄奕普; 陈敏; 刘广山

    2004-01-01

    Bacterial productivity was measured using 3H-thymidine methods in the Prydz Bay and its adjacent waters in the Southern Ocean during the 16th National Antarctic Research Expedition of China (CHINARE). The results showed that bacteted for the Ross Sea. The mean ratio of bacterial productivity to primary productivity in our study areas was 41%. The general characteristics in the vertical profiles showed a subsurface maximum at most of the stations, which was also consistent with those observed in the other sea areas in the Southern Ocean. The spatial distribution of bacterial productivity and dissolved organic carbon in the surface waters showed that their variations were inversely correlative. The relationship among bacterial productivity, primary productivity and dissolved organic carbon suggested that bacterial productivity in the Prydz Bay and its adjacent water was influenced mostly by phytoplankton activities and the hydrologic conditions.

  2. Gas samples of Afghanistan and adjacent areas (gasafg.shp)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of gas samples collected in Afghanistan and adjacent areas and the results of organic geochemical analysis.

  3. 45 CFR 670.29 - Designation of Antarctic Specially Protected Areas, Specially Managed Areas and Historic Sites...

    2010-10-01

    ... the Antarctic Treaty Parties for special protection and are hereby designated as Antarctic Specially... Elizabeth Land, East Antarctica (b) The following areas have been designated by the Antarctic Treaty Parties... Antarctica (c) The following areas have been designated by the Antarctic Treaty Parties as historic sites...

  4. Emission of pesticides during drilling and deposition in adjacent areas

    Heimbach, Udo

    2014-02-01

    Full Text Available In seven experiments seeds of maize, oil seed rape and barley, treated with neonicotinoids, were sown using pneumatic drilling equipment with deflectors attached in case of pneumatic suction systems. Directly adjacent to the drilled area of usually about 50 m width were replicated areas with bare soil as well as with crops. During maize (Zea mays drilling flowering oil seed rape (Brassica napus and during drilling of barley (Hordeum vulgare and oil seed rape flowering white mustard (Sinapis alba was adjacent. The amount of residues in the adjacent non crop areas in Petri dishes being distributed on the bare soil declined only slowly from 1 to 20 m distance from the area drilled. Seed batches with more abrasion and higher content of active substances in the dust resulted in higher residues off crop. After drilling of maize in four experiments in Petri dishes in adjacent non crop areas in 1-5 m distance between 0.02 and 0.40 g a.s./ha of neonicotinoids and in the adjacent oil seed rape a total of 0.05–0.80 g a.s./ha were detected. After drilling oil seed rape or barley these values were only 0.02–0.06 g a.s./ha in Petri dishes in non crop areas and 0.03-0.08 g a.s./ha in total in adjacent white mustard. In gauze net samplers installed vertically in 3 m distance in non crop areas up to seven times higher values were detected compared to Petri dishes.

  5. Geodynamical features and geotectonic evolution of Kalimantan and adjacent areas

    杨牧; 彭省临

    2004-01-01

    Kalimantan Island is located in the Southeast Asia continental marginal tectono-magmatic mobile zone in the West Pacific Ocean, where the lithosphere of Earth is one of the most complicated tectonic mobile regions on the Earth since Meso-Cenozoic. Based on the geophysical data of the basement and deep structures, the stress field of mantle flow, the maximum principal stress field and geothermal flux, the crustal nature and geodynamical features of Kalimantan Island and adjacent areas were analyzed. Researches on geotectonic movement and evolution of Kalimantan and adjacent areas show that Southeast Asia continental margin crustobody was formed at about middle-late Triassic. In addition, the geotectonic units of the Kalimantan area were subdivided, and characteristics of their geotectonic evolution were discussed.

  6. Heat flow distribution in Chinese continent and its adjacent areas

    Wei Tao; Zhengkang Shen

    2008-01-01

    Using a compilation of 6980 heat flow measurements, we produce a new heat flow map for the Chinese continent and its adjacent areas. We develop an objective and integrated method to interpolate the heat flow data, taking into account both the uniformity within geological units and coherency of regional heat flow. The geologic units are outlined based on Zhang et al.'s active tectonic block model.Our heat flow model is presented in two formats: a contour map and a heat flow dataset with values on a 1 × 1° grid for the Chinese continent and its adjacent areas, reflecting detailed variations in some regions. Also provided is a resolution map which helps understand the reliability of the heat flow model. Our results reveal that (1) Heat flows in the eastern part of the Chinese continent are relatively higher than those in the western part except that in the Tibetan Plateau area. (2) Heat flows in the Ordos and North China blocks are around 60 mW/m2, and are 50-55 mW/m2 in South China except for the continental marginal sea regions. (3) Heat flow is the lowest in the Jtmggar Basin, only 35-45 mW/m2, and is 45-55 mW/m2 in the Tarim Basin. The results of this study provide an important data-set for studies on thermal and rheological structures of the Chinese continent and its adjacent areas.

  7. Historical Earthquakes in the Yellow Sea and Its Adjacent Area

    Wu Ge; Wang Andong; Wu Di

    2005-01-01

    As a result of sorting out, estimating and cataloging of historical earthquakes, from the year of 2 A.D. to Aug., 1949, we found that there were 2187 earthquakes with M≥3.0 in the area of the Yellow Sea and its adjacent area. Among the earthquakes, the number of earthquakes with M ≥ 5.0 is 209, and at least 43 of the earthquakes caused serious losses, 20 of the earthquakes caused human causalities. It is demonstrated that there were 3 areas of historical earthquake concentration and the earthquake activity was higher in the 16th century and the first half if the 20th century.

  8. The Current Tectonics of the Yukon and Adjacent Area

    Hyndman, R. D.; Leonard, L. J.

    2014-12-01

    The current tectonics across the Yukon and adjacent areas of western Northwest Territories (NWT) and northern British Columbia appear to be driven primarily by the Yakutat Terrane collision, an "indenter" in the corner of the Gulf of Alaska. GPS data show 1-10 mm/yr northward and eastward, decreasing inland. The rates from earthquake statistics are similar although there are important discrepancies. The eastern Cordillera earthquake mechanisms are mainly thrust in the Mackenzie Mountains of southwestern NWT where the Cordillera upper crust is overthrusting the craton. To the north, the mechanisms are mainly strike-slip in the Richardson Mountains that appear to lie along the edge of the craton. The deformation appears to be limited to the hot and weak Cordillera with the strong craton providing an irregular eastern boundary. For example, there is an eastward bow in the craton edge and the deformation in the Mackenzie Mountains. On the Beaufort Sea margin in the region of the Mackenzie Delta there appears to be a type of "subduction zone" with the continent very slowly overthrusting the oceanic plate, a process that has continued since at least the Cretaceous. A northward moving continental margin block is bounded by left lateral faulting in the west (Canning Displacement Zone of eastern Alaska) and right lateral faulting in the east (Richardson Mountains in eastern Yukon). There is almost no seismicity on this thrust belt but as for some other subduction zones such as Cascadia there is the potential for very infrequent great earthquakes.

  9. Seismic motion attenuation relations in Sichuan and adjacent areas

    LEI Jian-cheng; GAO Meng-tan; YU Yan-xiang

    2007-01-01

    The Sichuan and adjacent areas is divided into southwest China region (SWCR) and Sichuan Basin region (SCBR) according to tectonic backgrounds and seismic damage distribution features. 96 modern destructive earthquakes in SWCR and 40 in SCBR are gathered respectively. All their magnitude parameters are checked. Based on the statistic relations between epicentral intensity and magnitude as well as relation between sensible radius and magnitude, the near and far field seismic intensity attenuation features are represented and controlled. And then the seismic intensity attenuation relations along major axis, minor axis and mean axis are established separately. The systematic deviations of surface wave magnitude between China seismograph network and U.S. seismograph network are considered in this paper. By making use of the new attenuation relations of bedrock horizontal ground acceleration response spectrum in west U.S., the attenuation relations of bedrock horizontal ground acceleration response spectrum in SWCR and SCBR are digital transformed based on the attenuation model considering acceleration saturation of distance and magnitude in near field.

  10. Hydrocarbon provinces and productive trends in Libya and adjacent areas

    Missallati, A.A. (Agip (N.A.M.E.)Ltd., Tripoli (Libya))

    1988-08-01

    According to the age of major reservoirs, hydrocarbon occurrences in Libya and adjacent areas can be grouped into six major systems which, according to their geographic locations, can be classified into two major hydrocarbon provinces: (1) Sirte-Pelagian basins province, with major reservoirs ranging from middle-late Mesozoic to early Tertiary, and (2) Murzog-Ghadames basins province, with major reservoirs ranging from early Paleozoic to early Mesozoic. In the Sirte-Pelagian basins province, hydrocarbons have been trapped in structural highs or in stratigraphic wedge-out against structural highs and in carbonate buildups. Here, hydrocarbon generation is characterized by the combined effect of abundant structural relief and reservoir development in the same hydrocarbon systems of the same age, providing an excellent example of hydrocarbon traps in sedimentary basins that have undergone extensive tensional fracturing in a shallow marine environment. In the Murzog-Ghadames basins province, hydrocarbons have been trapped mainly in structural highs controlled by paleostructural trends as basement arches which acted as focal points for oil migration and accumulation.

  11. 33 CFR 162.215 - Lake Tahoe, Nev.; restricted area adjacent to Nevada Beach.

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Lake Tahoe, Nev.; restricted area adjacent to Nevada Beach. 162.215 Section 162.215 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... § 162.215 Lake Tahoe, Nev.; restricted area adjacent to Nevada Beach. (a) The restricted area....

  12. Primary productivity, phytoplankton standing crop and physico-chemical characteristics of the Antarctic and adjacent central Indian Ocean waters

    JiyalalRam, M.

    Primary productivity, phytoplankton pigments and physico-chemical properties were studied in Antarctic waters and adjoining Indian Ocean between 11 degrees and 67 degrees E longitudes from polynya region (60 degrees S) to equator during the austral...

  13. Assessment of heavy metal levels in surface sediments of estuaries and adjacent coastal areas in China

    Liu, Xianbin; Li, Deliang; Song, Guisheng

    2017-03-01

    This article investigates the variations of contamination levels of heavy metals such as copper, lead, chromium, cadmium, zinc, arsenic, and mercury over time in surface sediments of the Changjiang River Estuary (CRE), Yellow River Estuary (YRE), Pearl River Estuary (PRE), and their adjacent coastal areas in China. The contamination factor (CF), pollution load index (PLI), and geoaccumulation index ( I geo) are used to evaluate the quality of the surface sediments in the study areas. The results showed that the CRE, YRE, and their adjacent coastal areas were at a low risk of contamination in terms of heavy metals, while the PRE and its adjacent coastal area were at a moderate level. By comparison, the concentrations of heavy metals in the surface sediments of the YRE and its adjacent coastal area were relatively lower than those in the CRE, PRE, and their adjacent coastal areas.

  14. 33 CFR 334.1060 - Oakland Outer Harbor adjacent to the Oakland Army Base; restricted area.

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Oakland Outer Harbor adjacent to the Oakland Army Base; restricted area. 334.1060 Section 334.1060 Navigation and Navigable Waters... REGULATIONS § 334.1060 Oakland Outer Harbor adjacent to the Oakland Army Base; restricted area. (a) The...

  15. The costs of living with elephants in the areas adjacent to Marsabit National Park and Reserve

    Ngene, S.M.; Omondi, P.

    2008-01-01

    Crop raiding by elephants is a serious management problem around protected areas in Kenya. This is because of changes in the land use systems in these areas, with crop farming occurring in areas where it did not previously. Crop raiding by elephants was monitored in the area adjacent to Marsabit Nat

  16. The Isostatic State of Ethiopia and Adjacent Areas

    Woldetinsae, G.; Götze, H.-J.

    2003-04-01

    Over 35000 onshore and offshore gravity stations have been compiled in order to test isostatic models and perform geologic correlations over a large section of the Afro-Arabian shield. Ethiopia is an important part of this system because it contains the major section of the ca. 5000km Afro-Arabian rift and it includes the transition between the Arabo-Nubian-Shield (ANS) and Mozambique Belt (MB). Isostatic residual anomalies have been calculated using both Airy and Vening-Meinsez models. These anomalies outline the major Precambrian belts, the Cenozoic rifts and associated major structures. Positive residual anomalies associated with the Main Ethiopian Rift (MER) and Kenyan rift systems could be the expression of an axial intrusive body and swarms of local faults and fractures. The residual anomalies indicate relative stability in the MER and increased tectonic activity over the areas of the Red Sea, Gulf of Aden and Afar. Near-zero isostatic residuals flank the MER and Kenya rifts and are found within the Danakil Alps and some plateau regions. A series of NW-SE and E-W trending features are evident in the different isostatic residual maps. These parallel features include, from north to south, the Najid fault system, Red Sea axial zone, Melka Werer cross structure, the Anza rift and the Aswa shear zone. Additional NW-SE structures are apparent in the southern rift system, although these features are somewhat diffuse. Curvature enhanced maps are also useful for mapping fracture zones, major gravity lineaments and, in some cases, orientation of faults. Important areas from a metallogenesis point of view have been identified for further examination. The results of the qualitative interpretation form the basis of continuing three-dimensional gravity modelling and qualitative analysis that also integrates data from eastern Sudan.

  17. Gravity field and isostatic state of Ethiopia and adjacent areas

    Woldetinsae, G.; Götze, H.-J.

    2005-01-01

    Over 35,000 onshore and offshore gravity stations have been compiled in order to test isostatic models against geologic structures over a part of the Afro-Arabian shield. The area of Ethiopia covers an important part of this system because it contains the major section of the ≈5000 km Afro-Arabian rift and includes the transition between the Arabo-Nubian-Shield (ANS) and the Mozambique Belt (MB). Isostatic residual anomalies have been calculated using both Airy and Vening-Meinesz (flexural rigidity D = 10 22 Nm) models. The isostatic residual anomalies outline the major Precambrian belts, the Cenozoic rifts and associated major structures. Positive residual anomalies associated with the main Ethiopian Rift (MER) and Kenyan rift systems could be the expressions of an axial intrusive body and swarms of local faults and fractures. The residual anomalies indicate relative stability in the MER and increased tectonic activity in the areas of the Red Sea, Gulf of Aden and Afar. Near-zero isostatic residuals flank the MER and Kenya rifts and are found within the Danakil Alps and some plateau regions. The small mean isostatic residual anomaly (about 8 mGal) and the isostatic analysis show a slight positive bias indicating under compensation. The undercompensation may imply that there are upper crustal features that are not compensated regionally (probably supported by the rigidity of the lithosphere) and isostatic disequilibrium in the region. Therefore, the high topography of Ethiopia and East African plateau is partly compensated by thicker crust (broad negative isostatic regional anomaly) and partly by dynamic forces. The results of the qualitative interpretation form the basis of continuing three-dimensional gravity modelling and quantitative analysis that also integrates data from eastern Sudan.

  18. The Brazilian research contribution to knowledge of the plant communities from Antarctic ice free areas

    ANTONIO B. PEREIRA

    2013-09-01

    Full Text Available This work aims to summarize the results of research carried out by Brazilian researchers on the plant communities of Antarctic ice free areas during the last twenty five years. Since 1988 field work has been carried out in Elephant Island, King George Island, Nelson Island and Deception Island. During this period six papers were published on the chemistry of lichens, seven papers on plant taxonomy, five papers on plant biology, two studies on UVB photoprotection, three studies about the relationships between plant communities and bird colonies and eleven papers on plant communities from ice free areas. At the present, Brazilian botanists are researching the plant communities of Antarctic ice free areas in order to understand their relationships to soil microbial communities, the biodiversity, the distribution of the plants populations and their relationship with birds colonies. In addition to these activities, a group of Brazilian researchers are undertaking studies related to Antarctic plant genetic diversity, plant chemistry and their biotechnological applications.

  19. Rock samples and geochemical analyses of Afghanistan and adjacent areas (rockafg.shp)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of rock samples (core samples and outcrop samples) collected in Afghanistan and adjacent areas, and the...

  20. Oil samples and geochemical analyses of Afghanistan and adjacent areas (oilafg.shp)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of oil samples collected in Afghanistan and adjacent areas, and the results of organic geochemical analysis.

  1. Coleoptera and microbe biomass in Antarctic Dry Valley paleosols adjacent to the Inland Ice: Implications for Mars

    Mahaney, William C.; Hart, Kris M.; O'Reilly, Shane S.; Allen, Christopher C. R.; Dohm, James M.; Hancock, Ronald G. V.; Kelleher, Brian P.; Milner, Michael W.

    2012-01-01

    Bulk paleosol samples collected from a Middle to Early Miocene moraine in the New Mountain area of the Dry Valleys, Antarctica, yielded Coleoptera exoskeletons and occasional endoskeletons showing considerable diagenetic effects along with several species of bacteria, all lodged in a dry-frozen but salt-rich horizon at shallow depth to the land surface. The till is at the older end of a chronologic sequence of glacial deposits, thought to have been deposited before the transition from wet-based to cold-based ice (∼15 Ma), and hence, entirely weathered in contact with the subaerial atmosphere. It is possible, though not absolutely verifiable, that the skeletons date from this early stage of emplacement having undergone modifications whenever light snowmelt occurred or salt concentrations lowered the freezing temperature to maintain water as liquid. Correlation of the Coleoptera species with cultured bacteria in the sample and the likelihood of co-habitation with Beauveria bassiani found in two adjacent, although younger paleosols, leads to new questions about the antiquity of the Coleoptera and the source of N and glucose from chitinase derived from the insects. The skeletons in the 831 section may date close to the oldest preserved chitin (Oligocene) yet found on Earth. While harsh Martian conditions make it seemingly intolerable for complex, multicellular organisms such as insects to exist in the near-surface and subaerially, life within similar cold, dry paleosol microenvironments (Cryosols) of Antarctica point to life potential for the Red Planet, especially when considering the relatively diverse microbe (bacteria and fungi) population.

  2. A Study on Snowstorm Weather in Coastal Area of Western Antarctic

    Huang Yaorong; Xue Zhenhe; Xu Cong

    2003-01-01

    In this paper, based on the observational data of 1995 in the Chinese Antarctic Great Wall Station the snowstorm is studied synoptically. It is found that there are two kinds of snowstorms with different physical characteristics and that the happening of snowstorm is always accompanied by a near-ground level inversion layer. The function of the inversion layer is analyzed, too. It is indicated that the strong ESE-wind type snowstorm is mainly caused by katabatic wind and gradient wind together. This idea is new and different from the general concept that there is no katabatic wind in the western Antarctic area.

  3. The temporal and spatial characteristics of the surface air temperature variations over the Antarctic and its surrounding area

    陆龙骅; 卞林根; 贾朋群

    1997-01-01

    The characteristics of the spatial distribution, temporal variations trend and oscillation for the surface air temperature variations during 1957-1993 in the Antarctic and its surrounding area were analyzed. The results show that the short-time climate change in the Antarctic is complex both temporally and spatially. The Antarctic is by no means the strongest responding region to the global greenhouse effect. There is a distinguished difference in the trends of the temperature changes for the Antarctic and global mean, which could not be explained simply by the global greenhouse effect.

  4. Computation and analysis of the geomagnetic field model in China and its adjacent area for 2003

    GU Zuo-wen; AN Zhen-chang; GAO Jin-tian; ZHAN Zhi-jia; YAO Tong-qi; HAN Wei; CHEN Bin

    2006-01-01

    Based on the geomagnetic data at 135 stations and 35 observatories in China in 2003, the Taylor polynomial model and the spherical cap harmonic model in China and its adjacent area for 2003 were established. In the model calculation, the truncation order of the model and the influences of the boundary restriction on the model calculation were carefully analyzed. The results show that the geomagnetic data used are precise and reliable, and the selection of the truncation order is reasonable. The Taylor polynomial model and the spherical cap harmonic model in China and its adjacent area established in this paper are consistent very well.

  5. Monitoring snow-cover area change in Antarctic coastline region using MODIS product data

    Chen Jing; Li Rendong; Ye Ming; Lu Yang

    2009-01-01

    Based on MODIS snow products, this article studied the changes of snow cover area during 2003-2006 along the coastline of the Antarctic, and 18 typical regions were chosen for further analysis. The result showed that the change of snow cover area was in a fluctuant downward trend as a whole, and more fluctuated obviously in warm season than in cold season. In temporal scale: for the season cycle, the snow cover extent increased rapidly in cold season (Apr-Oct), while the performance in warm season (Nov-Mar) was not exactly the same during the four years, the snow cover extent decreased in the first and then increased in 2004 and 2006, however, increased firstly and then decreased but reduced as a whole in 2005, for the inter-annual cycle, snow cover extent was the largest in 2003, but reached to the lowest level in 2004, and then increased gradually in 2005 and 2006, whereas, it declined with fluctuant as a whole. In spatial scale, changes mainly centralized along the coastline, moreover, it was more remarkable in the West Antarctic than in the East Antarctic, especially in the Antarctic Peninsula region.

  6. A GIS FOR THE ANTARCTIC SPECIALLY MANAGED AREA OF ADMIRALTY BAY,KING GEORGE ISLAND,ANTARCTICA

    2001-01-01

    ABSTRACT A GIS is proposed as a tool for the managing plan for the Antarctic specially managed area (ASMA) in Admiralty Bay.The ASMA comprises the area considered to be within the glacial drainage basin of the bay.Furthermore,it includes part of SSSI No.8 adjacent to the area but outside of the glacial drainage basin.Three stations and six refuges are located in the area.Using a SPOT satellite image map,the limits of the ASMA are marked and its area is re_calculated.It consists of 362 km2,including 186 km2 island ice field and small cirque glaciers and 32 km2 ice_free field.The rest comprises water of the bay and a small adjacent area (8 km2) of the Bransfield Strait. The ASMA_GIS will consists of 12 data layers ranging from the physiographic settings to the biological and administrative features.All data will be implemented into Arc/Info GIS according to the cartographic guidelines of the SCAR WG_GGI.First,five plans of information will be realised using a topographic database compiled from various sources and data from the revised bathymetric chart published by the Brazilian Navy Hydrographic Survey and also including: 1) Limits of the ASMA and protected areas;2) Glaciological features (e.g.drainage basin limits) and 3) Human presence (e.g.stations and historical sites).These basic GIS layers will be operational in early 2001.Then,additional data on the remaining layers (e.g.hydrology,geology and geomorphology) will be included from published sources. The ASMA_GIS will form an important database for environmental monitoring and studies surveying temporal changes of features such as glacier front positions or bird breading sites.

  7. Checklist of the Discomycetes (Fungi of Patagonia, Tierra del Fuego and adjacent antarctic areas

    Irma J. Gamundí

    2004-01-01

    Full Text Available La información brindada en este catálogo consiste en registrar las especies de hongos pertenecientes a los órdenes Cyttariales, Helotiales, Ostropales, Pezizales, Rhytismatales y Thelebolales (Discomycetes coleccionadas en Patagonia, Tierra del Fuego y áreas adyacentes antárticas (Patagonia. Además datos sobre sus organismos asociados fueron localizados, resumidos, validados y editados. Las fuentes de información fueron las exsiccatae depositadas en colecciones de Argentina y otros países y de las publicaciones listadas en la bibliografía. Otros registros derivaron de observaciones de campo sobre material fresco y colecciones de referencia. La información fue acumulada en un sistema computarizado relacional de datos taxonómicos, nomenclaturales, bibliográficos, de distribución geográfica y de observaciones biológicas. Este sistema permite la acumulación de datos paralelos en diferentes idiomas, y distingue la información original de la opinión corriente de lo que puede significar esa información. En la Biological Records Database, 5029 registros fueron creados para observaciones sobre la ocurrencia temporal y espacial de los organismos vivos de la región. De éstos, 2613 corresponden a registros de colecciones de Discomycetes de la Patagonia y Tierra del Fuego, con la siguiente distribución: 1854 para a la Argentina, 687 para Chile y 72 para áreas adyacentes antárticas. Excluyendo los sinónimos, los Discomycetes están representados por 361 especies y taxones subespecíficos (160 géneros, 22 familias y 7 órdenes. Los registros remanentes fueron de organismos asociados con los Discomycetes: 163 animales (8 especies, 8 géneros, 6 familias y 5 órdenes; 2 Chromista; 223 hongos (52 especies, 54 géneros, 26 familias y 13 ódenes; 2028 plantas (159 especies, 122 géneros, 59 familias y 39 órdenes. Cada uno de estos taxones (y cada sinónimo conocido está representado por un registro separado en la Base de Datos Taxonómica y Nomenclatural. La información sobre fuentes relevantes de bibliografía fue acumulada en más de 120 registros en la Base de Datos de Bibliografía. Un registro típico consiste en: nombre del hongo; autor(es; lugar original de la publicación del nombre; sinónimos conocidos. La clasificación a nivel genérico y superior sigue la 9th edición de Ainsworth & Bisby’s Dictionary of Fungi (Kirk et al., 2001. A estos datos sigue la información básica derivada de la base de datos: número de veces que la especie ha sido coleccionada en el área; fecha del primer registro para el área; meses en los cuales el hongo ha sido observado en el área; distribución geográfica por país, y dentro del país por subdivisiones apropiadas (Región, Provincia, Departamento; organismos asociados y sustrato, una lista de referencia de los números de colección de los especímenes preservados y citas bibliográficas de las fuentes de información y del identificador de cada colección. Se indica el status de cada nombre y, cuando es posible, los sinónimos y un índice cruzado. Esta lista se acompaña de una introducción, índice taxonómico, índice por país (y subdivisiones políticas, índice taxonómico de los organismos asociados, índice de sustratos y bibliografía. No se describen taxones nuevos, aunque sí cuatro nuevas combinaciones

  8. Glirinae (Gliridae, Rodentia) from the type area of the Aragonian and adjacent areas (provinces of Teruel and Zaragoza, Spain)

    Daams, R.

    1985-01-01

    This paper, the first in a series of monographs on the mammal faunas from the type area of the Aragonian and adjacent areas in the provinces of Teruel and Zaragoza, deals with the description and palaeoenvironmental interpretation of the Glirinae (Gliridae: dormice).

  9. Microbial biomass and basal respiration in Sub-Antarctic and Antarctic soils in the areas of some Russian polar stations

    E. Abakumov

    2014-03-01

    Full Text Available Antarctica is the unique place for pedological investigations. Soils of Antarctica have been studied intensively during the last century. Antarctic logistic provides the possibility to scientists access the terrestrial landscapes mainly in the places of polar stations. That is why the main and most detailed pedological investigations were conducted in Mc Murdo Valleys, Transantarctic Mountains, South Shetland Islands, Larsemann hills and Schirmacher Oasis. Investigations were conducted during the 53rd and 55th Russian Antarctic expeditions on the base of soil pits and samples collected in Sub-Antarctic and Antarctic regions. Soils of diverse Antarctic landscapes were studied with aim to assess the microbial biomass level, basal respiration rates and metabolic activity of microbial communities. The investigation conducted shows that soils of Antarctic are quite different in profile organization and carbon content. In general, Sub-Antarctic soils are characterized by more developed humus (sod organo-mineral horizons as well as the upper organic layer. The most developed organic layers were revealed in peat soils of King-George Island, where its thickness reach even 80 cm. These soils as well as soils under guano are characterized by the highest amount of total organic carbon (TOC 7.22–33.70%. Coastal and continental soils of Antarctic are presented by less developed Leptosols, Gleysols, Regolith and rare Ornhitosol with TOC levels about 0.37–4.67%. The metabolic ratios and basal respiration were higher in Sub-Antarctic soils than in Antarctic ones which can be interpreted as result of higher amounts of fresh organic remnants in organic and organo-mineral horizons. Also the soils of King-George island have higher portion of microbial biomass (max 1.54 mg g−1 than coastal (max 0.26 mg g−1 and continental (max 0.22 mg g−1 Antarctic soils. Sub-Antarctic soils mainly differ from Antarctic ones in increased organic layers thickness and total

  10. Testing EGM2008 on Leveling Data from Scandinavia, adjacent Baltic areas, and Greenland

    Strykowski, Gabriel; Forsberg, René

    2009-01-01

    We tested EGM2008 on GPS/leveling data from Scandinavia and adjacent areas. EGM2008 performs at the same level as the best regional geoid model, NKG2004. However, the direct evaluation of EGM2008 is difficult in Greenland because no leveling data are available. Nevertheless, we show on 78 GPS-MSS...

  11. Depth distribution of Moho and tectonic framework in eastern Asian continent and its adjacent ocean areas

    TENG; Jiwen; (滕吉文); ZENG; Rongsheng; (曾融生); YAN; Yafen; (闫雅芬); ZHANG; Hui; (张慧)

    2003-01-01

    With the results of interpretation of seismic sounding profiles acquired in the past 30 years in the continent of China and its adjacent countries andocean regions, such as Russia, Kazakhstan, Japan, India, Pakistan, Philippine ocean basin, Pacific and Indian Ocean, we compiled a 2D Moho distribution map forthe continent and its adjacent areas of eastern Asia. From the features of depth distribution and undulation of Moho, it is suggested that the eastern Asian region can be divided into 18 gradient belts with different sizes, 18 crustal blocks, 20 sediment basins and depression zones. The depth of Moho varies smoothly in each block, while the boundary (separating different blocks) delineates the abrupt variation of Moho depth. Then, some subjects,such as oregen and sediment basin, fault system and rift, plate boundary, ocean-continent coupling and tectonic framework, are discussed based on the distribution gradient belts and block partition features of Moho depth in the eastern Asia and its adjacent regions.

  12. 33 CFR 334.412 - Albemarle Sound, Pamlico Sound, Harvey Point and adjacent waters, NC; restricted area.

    2010-07-01

    ..., Harvey Point and adjacent waters, NC; restricted area. 334.412 Section 334.412 Navigation and Navigable... REGULATIONS § 334.412 Albemarle Sound, Pamlico Sound, Harvey Point and adjacent waters, NC; restricted area. (a) The area. Beginning on the north shore of Albemarle Sound and the easternmost tip of Harvey...

  13. Study on displacement field generated by aftershocks in Landers earthquake fault zone and its adjacent areas

    WAN Yong-ge; SHEN Zheng-kang; LAN Cong-xin

    2005-01-01

    The displacement field generated by aftershocks in Landers earthquake fault zone and its adjacent areas is calculated in this study. The result is compared with the displacement field of the main shock calculated by co-seismic slip model of Wald and Heaton (1994). The result shows that the direction of displacement generated by aftershocks in Landers seismic fault plane and its adjacent areas is consistent with that generated by main shock. The rupture of aftershock is generally inherited from main shock. The displacement generated by aftershocks is up to an order of centimeter and can be measured by GPS sites nearby. So when we use geodetic data measured after earthquake to study the geophysical problems such as crustal viscosity structure, afterslip distribution, etc., only the displacement field generated by aftershocks considered, can uncertainty be reduced to minimum and realistic result be obtained.

  14. A sea temperature data assimilation system for the China Seas and adjacent areas

    YOU Xiaobao; ZHOU Guangqing; ZHU Jiang; LI Rongfeng

    2003-01-01

    A sea temperature data assimilation system for the China Seas and adjacent areas is developed based on a nested regional ocean circulation model and variational optimal interpolation assimilation method. A 12-year assimilation experiment is performed by using the observational temperature profiles from World Ocean Database 1998 (WOD98) and ECMWF reanalysis surface wind stress. Experimental results indicate that the variational scheme shows good skill in assimilating the observed sea temperature into a regional ocean circulation model. Compared with simulation alone, the sea temperature data assimilation significantly improves the performance of a regional ocean model and obtains comprehensive description of the circulations in the China Seas and adjacent areas. Assimilation results, such as the strength and flowing axis of the Kuroshio, Yellow Sea Cold Water Mass and its corresponding horizontal circulation in summer and dipole eddies in the South China Sea in the late summer/early autumn and the eastward jet between them, are well consistent with the observed evidences.

  15. Current status of chrono stratigraphic units named from Belgium and adjacent areas

    Léon Dejonghe

    2007-01-01

    @@ The recommendations of the InternationalCommission on Stratigraphy edited in 1976by Hedberg and in 1994 by Salvador havegenerally been well accepted by the Belgiancommunity of geologists as represented bynational stratigraphic subcommissions set upunder the Belgian National Committee ofGeological Sciences. However, the applica-tion of these recommendations has takensome time and the need has been felt for doc-uments to synthesise the current situationregarding stratigraphic units named fromBelgium and adjacent areas.

  16. Distribution Patterns of Human Elephant Conflict in Areas Adjacent to Rungwa Game Reserve, Tanzania

    Munuo, Wilbright

    2016-01-01

    Abstract Human pressure on terrestrial ecosystems has caused loss and fragmentation of habitats for wildlife species. That has brought humans and wildlife in close proximity intensifying human wildlife conflicts, especially when wild animals with wide home ranges, such as African and Asian elephants, are involved. This study assesses distribution patterns of human elephant conflict (HEC) in areas adjacent to Rungwa Game Reserve (RGR) in Tanzania. Questionnaire survey was used as a tool fo...

  17. Testing EGM2008 on Leveling Data from Scandinavia, Adjacent Baltic Areas, and Greenland

    Strykowski, Gabriel; Forsberg, René

    2010-01-01

    We tested EGM2008 on GPS/leveling data from Scandinavia and adjacent areas. EGM2008 performs at the same level as the best regional geoid model, NKG2004. However, the direct evaluation of EGM2008 is difficult in Greenland because no leveling data are available. Nevertheless, we show on 78 GPS......-MSS data that EGM2008 also performs at the same level as the best regional geoid model GOCINA04....

  18. Distribution of metals and trace elements in adult and juvenile penguins from the Antarctic Peninsula area.

    Jerez, Silvia; Motas, Miguel; Benzal, Jesús; Diaz, Julia; Vidal, Virginia; D'Amico, Verónica; Barbosa, Andrés

    2013-05-01

    The presence of metals in the Antarctic environment is principally a natural phenomenon caused by geochemical characteristics of the region, although some anthropogenic activities can increase these natural levels. Antarctic penguins present several of the characteristics of useful sentinels of pollution in Antarctica such as they are long-lived species situated at the top of food web. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd, and Pb were determined by inductively coupled plasma-mass spectrometry in samples of liver, kidney, muscle, bone, feather, and stomach contents of gentoo, chinstrap, and Adélie penguin (12 adults, five juveniles) from carcasses of naturally dead individuals collected opportunistically in the Antarctic Peninsula area. The obtained results showed that accumulation and magnification of several elements can be occurring, so that Cd and Se reached levels potentially toxic in some specimens. The presence of human activities seems to be increasing the presence of toxic metals such as Mn, Cr, Ni, or Pb in penguins.

  19. Some features of soil organic matter in parks and adjacent residential areas of Moscow

    Prokof'eva, T. V.; Rozanova, M. S.; Poputnikov, V. O.

    2013-03-01

    The humus-accumulative horizons of soils from two natural-historical parks of Moscow and the adjacent residential areas were studied. An increase in the concentration of organic matter was observed in the soils of the residential areas. A tendency toward the formation of fulvate humus typical for southern taiga soils persisted in the low-carbonate nongleyed humus-accumulative horizons. At the same time, the transformation rate, character, and content of organic matter in the urban soils were strongly affected by the contamination, calcareous invasion, and remediation of the soils and sediments.

  20. Water resources of the Waccasassa River Basin and adjacent areas, Florida

    Taylor, G.F.; Snell, L.J.

    1978-01-01

    This map report was prepared in cooperation with the Southwest Florida Water Management District which, with the Waccasassa River Basin Board, had jurisdiction over waters within the Waccasassa River basin, the coastal areas adjacent to the basin, and other adjacent areas outside the basin. New water management district boundaries, effective January 1977, place most of the Waccasassa River basin in the Suwannee River Water Management District. The purpose of the report is to provide water information for consideration in land-use and water development which is accelerating, especially in the northeastern part of the study area. It is based largely on existing data in the relatively undeveloped area. Of the total area included in the topographic drainage basin for the Waccasassa River about 72 percent is in Levy County, 18 percent in Alachua County, 9 percent in Gilchrist County, and 1 percent in Marion County. The elongated north-south drainage basin is approximately 50 mi in length, averages 13 mi in width, and lies between the Suwannee River, the St. Johns River, and the Withlacoochee River basins. (Woodard-USGS)

  1. Literature and data review for the surface-water pathway: Columbia River and adjacent coastal areas

    Walters, W.H.; Dirkes, R.L.; Napier, B.A.

    1992-11-01

    As part of the Hanford Environmental Dose Reconstruction (HEDR) Project, Battelle, Pacific Northwest Laboratories reviewed literature and data on radionuclide concentrations and distribution in the water, sediment, and biota of the Columbia River and adjacent coastal areas. Over 600 documents were reviewed including Hanford reports, reports by offsite agencies, journal articles, and graduate theses. Radionuclide concentration data were used in preliminary estimates of individual dose for the period 1964 through 1966. This report summarizes the literature and database reviews and the results of the preliminary dose estimates.

  2. Literature and data review for the surface-water pathway: Columbia River and adjacent coastal areas

    Walters, W.H.; Dirkes, R.L.; Napier, B.A.

    1992-04-01

    As part of the Hanford Environmental Dose Reconstruction Project, Pacific Northwest Laboratory reviewed literature and data on radionuclide concentrations and distribution in the water, sediment, and biota of the Columbia River and adjacent coastal areas. Over 600 documents were reviewed including Hanford reports, reports by offsite agencies, journal articles, and graduate theses. Certain radionuclide concentration data were used in preliminary estimates of individual dose for the 1964--1966 time period. This report summarizes the literature and database review and the results of the preliminary dose estimates.

  3. Odonata (Insecta diversity of Salim Ali Bird Sanctuary and its adjacent areas in Thattekkad, Kerala, India

    A.P. Varghese

    2014-06-01

    Full Text Available Odonata diversity of Salim Ali Bird Sanctuary and its adjacent areas in Thattekkad, Kerala, India were documented from 2010 to 2012. Opportunistic observations were carried out to record species diversity. Eighty-two species of Odonata, which included 51 species of Anisoptera (dragonflies and 31 species of Zygoptera (damselflies, were recorded during the study. Of this 21 species are endemic to the Western Ghats. The presence of the IUCN categorized nearly threatened species like Megalogomphus hannyngtoni and vulnerable species like Platysticta deccanensis and Protosticta sanguinostigma is remarkable.

  4. Late Cenozoic Tectonic Deformation in the Dongsha Islands and Adjacent Sea Area

    WU Shiguo(吴时国); LIU Zhan(刘展); WANG Wanyin(王万银); GUO Junhua(郭军华); T. Lüdmann; H. K. Wong

    2003-01-01

    Dongsha Island and the adjacent sea area locate at the northern continental margin of the South China Sea (SCS), and is connected to the east by the Manila Trench. Analyses of seismic stratigraphy and gravity, magnetic and drilling wells data led to the discovery of three post-fault sequences (V, VI, VII). Extensive tectonic uplift, magma activity and erosion occurred in Dongsha Island and the adjacent area, where most of the faults in the northeastern SCS were still active during Pliocene and Quaternary. Two groups of faults trending NEE and NW were developed during Late Cenozoic. We conclude that three important tectonic movements, especially Dongsha movement (4.4-5.2 Ma) and Liuhua movement (1.4-1.89 Ma), controlled the structural framework in the Dongsha rise; whose deformation in the east is stronger than that in the west and whose stress field variation suggests that the tectonic uplift in the study area contributed to magmato-tectonic events correlated to the main collision phases between the East China and Taiwan 5-3 and 3-0 Ma ago.

  5. Investigation on Reflection of Tectonic Pattern in ASG EUPOS Data in the Sudetes and Adjacent Areas

    Szczerbowski Zbigniew

    2016-12-01

    Full Text Available The GNSS data evaluated from on observation of ASG EUPOS stations in the Sudety Mts. and in adjacent areas is analyzed by the author in the scope of disturbances in daily solutions that can be induced by tectonics stress. The daily position changes derived from GNSS data demonstrate the long or short term trends, which are affected by offsets of different nature. Author presents an analysis based on frequency of parameter – displacement vector azimuth. The aim of the analysis is to show statistical significance of observed small values of temporal displacements, which values are not normally distributed. There are “outliers” of the normal distribution of displacement azimuths, which values show a certain reproducibility, which corresponds to orientations of tectonic lines. That suggests small, short time movements along boundaries of horsts and grabens – a crustal-extension structure of the area. However derived results (values of displacements are less than a limitation error, temporal distributions of coordinates are not random as usually data errors. So in author’s opinion the spatial-temporal evolution of horizontal displacements of ASG EUPOS stations in the Sudety Mts. and in adjacent areas are determined by expressions of underlying geological structures.

  6. Azimuthal anisotropy of Rayleigh waves beneath the Tibetan Plateau and adjacent areas

    2008-01-01

    The crustal and upper mantle azimuthal anisotropy of the Tibetan Plateau and adjacent areas was studied by Rayleigh wave tomography. We collected sufficient broadband digital seismograms trav-ersing the Tibetan Plateau and adjacent areas from available stations, including especially some data from the temporary stations newly deployed in Yunnan, eastern Tibet, and western Sichuan. They made an adequate path coverage in most regions to achieve a reasonable resolution for the inversion. The model resolution tests show that the anisotropic features of scope greater than 400 km and strength greater than 2% are reliable. The azimuthal anisotropy pattern inside the Tibetan Plateau was similar to the characteristic of tectonic partition. The crustal anisotropy strength is greater than 2% in most re-gions of East Tibet, and the anisotropy shows clockwise rotation surrounding the eastern Himalayan syntaxis. Vertically, the anisotropy direction indicates a coherent pattern within the upper crust, lower crust, and lithosphere mantle of the Tibetan Plateau, which also is consistent with GPS velocity field and SKS fast polarization directions. The result supports that the crust-mantle deformation beneath the Tibetan Plateau is vertically coherent. The anisotropy strength of crust and lithospheric upper mantle in Yunnan outside the Tibetan Plateau is lower than 2%, so SKS splitting from core-mantle boundary to station should largely be attributed to the anisotropy of asthenosphere.

  7. Azimuthal anisotropy of Rayleigh waves beneath the Tibetan Plateau and adjacent areas

    SU Wei; WANG ChunYong; HUANG ZhongXian

    2008-01-01

    The crustal and upper mantle azimuthal anisotropy of the Tibetan Plateau and adjacent areas was studied by Rayleigh wave tomography. We collected sufficient broadband digital seismograms traversing the Tibetan Plateau and adjacent areas from available stations, including especially some data from the temporary stations newly deployed in Yunnan, eastern Tibet, and western Sichuan. They made an adequate path coverage in most regions to achieve a reasonable resolution for the inversion. The model resolution tests show that the anisotropic features of scope greater than 400 km and strength greater than 2% are reliable. The azimuthal anisotropy pattern inside the Tibetan Plateau was similar to the characteristic of tectonic partition. The crustal anisotropy strength is greater than 2% in most regions of East Tibet, and the anisotropy shows clockwise rotation surrounding the eastern Himalayan syntaxis. Vertically, the anisotropy direction indicates a coherent pattern within the upper crust, lower crust, and lithosphere mantle of the Tibetan Plateau, which also is consistent with GPS velocity field and SKS fast polarization directions. The result supports that the crust-mantle deformation beneath the Tibetan Plateau is vertically coherent. The anisotropy strength of crust and lithospheric upper mantle in Yunnan outside the Tibetan Plateau is lower than 2%, so SKS splitting from core-mantle boundary to station should largely be attributed to the anisotropy of asthenosphere.

  8. Circummandibular Wires for Treatment of Dentoalveolar Fractures Adjacent to Edentulous Areas: A Report of Two Cases.

    Maloney, Karl

    2015-09-01

    In general, dentoalveolar fractures are a common injury seen in emergency departments, dental offices, and oral and maxillofacial surgery practices. These injuries can be the result of direct trauma or indirect trauma. Direct trauma more often causes trauma to the maxillary dentition due to the exposure of the maxillary anterior teeth. Indirect trauma is usually the result of forced occlusion secondary to a blow to the chin or from a whiplash injury. Falls are the most common mechanism of injury seen in the pediatric group. In adolescents, many of these fractures are sustained during sporting activities. However, the use of mouth guards and other protective equipment has decreased this number. Most adult injuries are caused by motor vehicle accidents, contact sports, falls, bicycles, interpersonal violence, medical/dental mishaps, and industrial accidents. Early intervention to reduce and stabilize the fracture is required to establish a bony union and ensure correct function. Most dentoalveolar fractures have bilateral stable adjacent dentition and are treated with a closed technique utilizing an acid-etch/resin splint followed by splint removal at 4 weeks. Other inferior stabilization treatments used are arch bars and other wiring techniques. It is widely accepted that semirigid stabilization techniques, such as an acid-etch/resin splint or wiring procedures, are adequate to treat dentoalveolar fractures. This is in contrast to the treatment of mandible fractures where AO principles of rigid fixation are often followed. Fractures that are unable to be reduced sometimes necessitate an open reduction followed by internal fixation, sometimes using a secondary splint for mobile teeth. In those rare cases when there are not stable adjacent teeth bilaterally other modalities must be considered. In the present report, two cases are presented where circummandibular wires were used to treat fractured mandibular dentoalveolar segments adjacent to edentulous areas.

  9. Landsat-faciliated vegetation classification of the Kenai National Wildlife Refuge and adjacent areas, Alaska

    Talbot, S. S.; Shasby, M.B.; Bailey, T.N.

    1985-01-01

    A Landsat-based vegetation map was prepared for Kenai National Wildlife Refuge and adjacent lands, 2 million and 2.5 million acres respectively. The refuge lies within the middle boreal sub zone of south central Alaska. Seven major classes and sixteen subclasses were recognized: forest (closed needleleaf, needleleaf woodland, mixed); deciduous scrub (lowland and montane, subalpine); dwarf scrub (dwarf shrub tundra, lichen tundra, dwarf shrub and lichen tundra, dwarf shrub peatland, string bog/wetlands); herbaceous (graminoid meadows and marshes); scarcely vegetated areas ; water (clear, moderately turbid, highly turbid); and glaciers. The methodology employed a cluster-block technique. Sample areas were described based on a combination of helicopter-ground survey, aerial photo interpretation, and digital Landsat data. Major steps in the Landsat analysis involved: preprocessing (geometric connection), spectral class labeling of sample areas, derivation of statistical parameters for spectral classes, preliminary classification of the entree study area using a maximum-likelihood algorithm, and final classification through ancillary information such as digital elevation data. The vegetation map (scale 1:250,000) was a pioneering effort since there were no intermediate-sclae maps of the area. Representative of distinctive regional patterns, the map was suitable for use in comprehensive conservation planning and wildlife management.

  10. Antarctic Entomology.

    Chown, Steven L; Convey, Peter

    2016-01-01

    The Antarctic region comprises the continent, the Maritime Antarctic, the sub-Antarctic islands, and the southern cold temperate islands. Continental Antarctica is devoid of insects, but elsewhere diversity varies from 2 to more than 200 species, of which flies and beetles constitute the majority. Much is known about the drivers of this diversity at local and regional scales; current climate and glacial history play important roles. Investigations of responses to low temperatures, dry conditions, and varying salinity have spanned the ecological to the genomic, revealing new insights into how insects respond to stressful conditions. Biological invasions are common across much of the region and are expected to increase as climates become warmer. The drivers of invasion are reasonably well understood, although less is known about the impacts of invasion. Antarctic entomology has advanced considerably over the past 50 years, but key areas, such as interspecific interactions, remain underexplored.

  11. Geochemical changes at the Permian–Triassic transition in Southern Alps and adjacent area: a review

    Aymon Baud

    2005-10-01

    Full Text Available Compilation of the recent literature from the Southern Alps and adjacent area confirms the geochemical variations of unusual amplitudes during the Permian-Triassic boundary interval (PTBI. A great attention has been given to the negative δ13C anomaly within the Tesero Member close to the Permian-Triassic boundary. Very detailed geochemical works have been done on the scientific Gartnerkofel core (Gk-1 and on the Slovenian sections. Major minor and rare earth elements (REE data are reported and show a marked enrichment in alkaline metals and REE of some levels of the boundary interval. But recent studies show that the low Iridium anomalies and the Osmium and Helium isotopes anomalies lack the characteristics of a large extraterrestrial impact.

  12. Ground-water resources of southern Tangipahoa Parish and adjacent areas, Louisiana

    Rapp, T.R.

    1994-01-01

    Groundwater resources in southern Tangipahoa Parish and adjacent areas were studied to determine their potential for development as an alternative to the Mississippi River as a water-supply source for Jefferson Parish. Eight major aquifers consisting of thick sand units that underlie the study area are, in descending order: (1) shallow, (2) upper Ponchatoula, (3) lower Ponchatoula, (4) Abita, (5) Covington, (6) Tchefuncta, (7) Hammond, and (8) Amite. A fault zone, referred to as the Baton Rouge fault, crosses southern Tangipahoa Parish. Analyses of geophysical logs indicated that the deep aquifers south of the fault zone had been displaced from 350 to 400 feet, and that the deeper aquifers were not in hydraulic connection with the flow system north of the fault. The groundwater resources of southeastern Louisiana are immense and the quality of groundwater in Tangipahoa Parish is suitable for most uses. The quality of water in these aquifers generally meets the U.S. Environmental Protection Agency's standards for public supply. The hydrologic system underlying Tangipahoa Parish and adjacent areas in 1990 supplied about 19 Mgal/d of water that was suitable for public supply. However, substantial increases in pumping from the aquifer system would result in renewed water-level declines throughout the hydrologic system until a new equilibrium is established. A test we11 in southern Tangipahoa Parish, penetrated all eight aquifers. Total thickness of freshwater sand beds penetrated by the 3003-ft test hole was more than 1900 ft. Resistivity values from an electric log of the test typically averaged 200 ohm-meters, which indicates that the water has low dissolved-solids and chloride concentrations. An analysis of the Abita aquifer at Ruddock in St. John the Baptist Parish, for two of three hypothetical well fields, indicated that for a hypothetical we11 field with a pumping rate of 112 Mgal/d, the freshwater/saltwater interface could arrive at the outer perimeter we11 in

  13. Wavelet Analysis of Earthquake Activity in the West of the Chinese Mainland and Its Adjacent Area

    Shao Huicheng; Fu Zhengxiang; Wang Xiaoqing; Jiang Zaisen

    2005-01-01

    Wavelets are a useful tool for analyzing the time-frequency of a non-stable series and are widely applied in many fields. The process of earthquake preparation and occurrence is a non-linear process. In the paper, the wavelet method is used to analyze the series of earthquake data for the time period from 1900 to 2003 in the west of the Chinese mainland and its adjacent area (WCMAA), and to obtain the characteristic information for different time scales. In the past 103 years, there were four primary periods of regional earthquake activity in the area with durations of 42, 22, 7 and 14 years, respectively and the intensity of earthquake activity changing with time. It doesn't make sense to talk about active or quiet periods of earthquake activity unless it is based on a specific time scale. In addition, the tendency analysis of earthquake activity using the primary period of seismic activity and wavelet coefficients of varied time scales indicates that the earthquake activity in this region will be high in the forthcoming years.

  14. Dynamic factor analysis of groundwater quality trends in an agricultural area adjacent to Everglades National Park.

    Muñoz-Carpena, R; Ritter, A; Li, Y C

    2005-11-01

    The extensive eastern boundary of Everglades National Park (ENP) in south Florida (USA) is subject to one of the most expensive and ambitious environmental restoration projects in history. Understanding and predicting the water quality interactions between the shallow aquifer and surface water is a key component in meeting current environmental regulations and fine-tuning ENP wetland restoration while still maintaining flood protection for the adjacent developed areas. Dynamic factor analysis (DFA), a recent technique for the study of multivariate non-stationary time-series, was applied to study fluctuations in groundwater quality in the area. More than two years of hydrological and water quality time series (rainfall; water table depth; and soil, ground and surface water concentrations of N-NO3-, N-NH4+, P-PO4(3-), Total P, F-and Cl-) from a small agricultural watershed adjacent to the ENP were selected for the study. The unexplained variability required for determining the concentration of each chemical in the 16 wells was greatly reduced by including in the analysis some of the observed time series as explanatory variables (rainfall, water table depth, and soil and canal water chemical concentration). DFA results showed that groundwater concentration of three of the agrochemical species studied (N-NO3-, P-PO4(3-)and Total P) were affected by the same explanatory variables (water table depth, enriched topsoil, and occurrence of a leaching rainfall event, in order of decreasing relative importance). This indicates that leaching by rainfall is the main mechanism explaining concentration peaks in groundwater. In the case of N-NH4+, in addition to leaching, groundwater concentration is governed by lateral exchange with canals. F-and Cl- are mainly affected by periods of dilution by rainfall recharge, and by exchange with the canals. The unstructured nature of the common trends found suggests that these are related to the complex spatially and temporally varying land

  15. Dynamic factor analysis of groundwater quality trends in an agricultural area adjacent to Everglades National Park

    Muñoz-Carpena, R.; Ritter, A.; Li, Y. C.

    2005-11-01

    The extensive eastern boundary of Everglades National Park (ENP) in south Florida (USA) is subject to one of the most expensive and ambitious environmental restoration projects in history. Understanding and predicting the water quality interactions between the shallow aquifer and surface water is a key component in meeting current environmental regulations and fine-tuning ENP wetland restoration while still maintaining flood protection for the adjacent developed areas. Dynamic factor analysis (DFA), a recent technique for the study of multivariate non-stationary time-series, was applied to study fluctuations in groundwater quality in the area. More than two years of hydrological and water quality time series (rainfall; water table depth; and soil, ground and surface water concentrations of N-NO 3-, N-NH 4+, P-PO 43-, Total P, F -and Cl -) from a small agricultural watershed adjacent to the ENP were selected for the study. The unexplained variability required for determining the concentration of each chemical in the 16 wells was greatly reduced by including in the analysis some of the observed time series as explanatory variables (rainfall, water table depth, and soil and canal water chemical concentration). DFA results showed that groundwater concentration of three of the agrochemical species studied (N-NO 3-, P-PO 43-and Total P) were affected by the same explanatory variables (water table depth, enriched topsoil, and occurrence of a leaching rainfall event, in order of decreasing relative importance). This indicates that leaching by rainfall is the main mechanism explaining concentration peaks in groundwater. In the case of N-NH 4+, in addition to leaching, groundwater concentration is governed by lateral exchange with canals. F -and Cl - are mainly affected by periods of dilution by rainfall recharge, and by exchange with the canals. The unstructured nature of the common trends found suggests that these are related to the complex spatially and temporally varying

  16. Origin of tectonic stresses in the Chinese continent and adjacent areas

    ZHU ShouBiao; SHI YaoLin

    2007-01-01

    Based on data of principal stress orientation from focal mechanism and of geological features in China, we made pseudo-3D genetic algorithm finite element (GA-FEM) inversion to investigate the main forces acting on the Chinese continent and adjacent areas which form the Chinese tectonic stress field. The results confirm that plate boundary forces play the dominant role in forming the stress field in China, as noticed by many previous researchers. However, we also find that topographic spreading forces, as well as basal drag forces of the lower crust to the upper crust, make significant contribution to stresses in regional scale. Forces acting on the Chinese continent can be outlined as follows: the collision of the India plate to the NNE is the most important action, whereby forces oriented to the NW by the Philippine plate and forces oriented to the SWW by the Pacific plate are also important. Topographic spreading forces are not negligible at high topographic gradient zones, these forces are perpendicular to edges of the Tibetan Plateau and a topographic gradient belt running in the NNE direction across Eastern China. Basal drag forces applied by the ductile flow of the lower crust to the base of upper crust affect the regional stress field in the Tibetan Plateau remarkably, producing the clockwise rotation around the eastern Himalaya syntax.

  17. Global projections of 21st century land-use changes in regions adjacent to Protected Areas.

    Linda J Beaumont

    Full Text Available The conservation efficiency of Protected Areas (PA is influenced by the health and characteristics of the surrounding landscape matrix. Fragmentation of adjacent lands interrupts ecological flows within PAs and will decrease the ability of species to shift their distribution as climate changes. For five periods across the 21(st century, we assessed changes to the extent of primary land, secondary land, pasture and crop land projected to occur within 50 km buffers surrounding IUCN-designated PAs. Four scenarios of land-use were obtained from the Land-Use Harmonization Project, developed for the Intergovernmental Panel on Climate Change's Fifth Assessment Report (AR5. The scenarios project the continued decline of primary lands within buffers surrounding PAs. Substantial losses are projected to occur across buffer regions in the tropical forest biomes of Indo-Malayan and the Temperate Broadleaf forests of the Nearctic. A number of buffer regions are projected to have negligible primary land remaining by 2100, including those in the Afrotropic's Tropical/Subtropical Grassland/Savanna/Shrubland. From 2010-2050, secondary land is projected to increase within most buffer regions, although, as with pasture and crops within tropical and temperate forests, projections from the four land-use scenarios may diverge substantially in magnitude and direction of change. These scenarios demonstrate a range of alternate futures, and show that although effective mitigation strategies may reduce pressure on land surrounding PAs, these areas will contain an increasingly heterogeneous matrix of primary and human-modified landscapes. Successful management of buffer regions will be imperative to ensure effectiveness of PAs and to facilitate climate-induced shifts in species ranges.

  18. Global projections of 21st century land-use changes in regions adjacent to Protected Areas.

    Beaumont, Linda J; Duursma, Daisy

    2012-01-01

    The conservation efficiency of Protected Areas (PA) is influenced by the health and characteristics of the surrounding landscape matrix. Fragmentation of adjacent lands interrupts ecological flows within PAs and will decrease the ability of species to shift their distribution as climate changes. For five periods across the 21(st) century, we assessed changes to the extent of primary land, secondary land, pasture and crop land projected to occur within 50 km buffers surrounding IUCN-designated PAs. Four scenarios of land-use were obtained from the Land-Use Harmonization Project, developed for the Intergovernmental Panel on Climate Change's Fifth Assessment Report (AR5). The scenarios project the continued decline of primary lands within buffers surrounding PAs. Substantial losses are projected to occur across buffer regions in the tropical forest biomes of Indo-Malayan and the Temperate Broadleaf forests of the Nearctic. A number of buffer regions are projected to have negligible primary land remaining by 2100, including those in the Afrotropic's Tropical/Subtropical Grassland/Savanna/Shrubland. From 2010-2050, secondary land is projected to increase within most buffer regions, although, as with pasture and crops within tropical and temperate forests, projections from the four land-use scenarios may diverge substantially in magnitude and direction of change. These scenarios demonstrate a range of alternate futures, and show that although effective mitigation strategies may reduce pressure on land surrounding PAs, these areas will contain an increasingly heterogeneous matrix of primary and human-modified landscapes. Successful management of buffer regions will be imperative to ensure effectiveness of PAs and to facilitate climate-induced shifts in species ranges.

  19. Geologic map of Colorado National Monument and adjacent areas, Mesa County, Colorado

    Scott, Robert B.; Harding, Anne E.; Hood, William C.; Cole, Rex D.; Livaccari, Richard F.; Johnson, James B.; Shroba, Ralph R.; Dickerson, Robert P.

    2001-01-01

    New 1:24,000-scale geologic mapping in the Colorado National Monument Quadrangle and adjacent areas, in support of the USGS Western Colorado I-70 Corridor Cooperative Geologic Mapping Project, provides new interpretations of and data for the stratigraphy, structure, geologic hazards in the area from the Colorado River in Grand Valley onto the Uncompahgre Plateau. The plateau drops abruptly along northwest-trending structures toward the northeast 800 m to the Redlands area and the Colorado River in Grand Valley. In addition to common alluvial and colluvial deposits, surficial deposits include Holocene and late Pleistocene charcoal-bearing valley-fill deposits, late to middle Pleistocene river-gravel terrace deposits, Holocene to middle Pleistocene younger, intermediate, and old fan-alluvium deposits, late to middle Pleistocene local gravel deposits, Holocene to late Pleistocene rock-fall deposits, Holocene to middle Pleistocene young and old landslide deposits, Holocene to late Pleistocene sheetwash deposits and eolian deposits, and Holocene Cienga-type deposits. Only the lowest part of the Upper Cretaceous Mancos Shale is exposed in the map area near the Colorado River. The Upper and Lower? Cretaceous Dakota Formation and the Lower Cretaceous Burro Canyon Formation form resistant dipslopes in the Grand Valley and a prominent ridge on the plateau. Less resistant strata of the Upper Jurassic Morrison Formation consisting of the Brushy Basin, Salt Wash, and Tidwell Members form slopes on the plateau and low areas below the mountain front of the plateau. The Middle Jurassic Wanakah Formation nomenclature replaces the previously used Summerville Formation. Because an upper part of the Middle Jurassic Entrada Formation is not obviously correlated with strata found elsewhere, it is therefore not formally named; however, the lower rounded cliff former Slickrock Member is clearly present. The Lower Jurassic silica-cemented Kayenta Formation forms the cap rock for the Lower

  20. Induced seismicity caused by hydraulic fracturing in deep geothermal wells in Germany and adjacent areas

    Plenefisch, Thomas; Brückner, Lisa; Ceranna, Lars; Gestermann, Nicolai; Houben, Georg; Tischner, Torsten; Wegler, Ulrich; Wellbrink, Matthias; Bönnemann, Christian; Bertram, Andreas; Kirschbaum, Bernd

    2016-04-01

    Recently, the BGR has worked out a study on the potential environmental impact caused by hydraulic fracturing or chemical stimulations in deep geothermal reservoirs in Germany and adjacent areas. The investigations and analyses are based on existing studies and information provided by operators. The two environmental impacts being essentially considered in the report are induced seismicity and possible contamination of the groundwater reservoirs which serve for drinking water supply. Altogether, in this study, information on 30 hydraulic frac operations and 26 chemical stimulations including information from neighboring countries were compiled and analyzed. Out of the hydraulic stimulations two thirds were carried out as waterfracs and one third as fracturing with proppants. Parameters used in the study to characterize the induced seismicity are maximum magnitude, number of seismic events, size of the seismically active volume, and the relation of this volume to fault zones and the cap rock, as well as, finally, the impacts at the Earth's surface. The response of the subsurface to hydraulic fracturing is variable: There are some activities, which cause perceptible seismic events, others, where no perceptible but instrumentally detected events occurred, and moreover activities without even any instrumentally detected events. A classification of seismic hazard with respect to tectonic region, geology, or depth of the layer is still difficult, since the number of hydraulic fracturing measures in deep geothermal wells is small making a statistically sound analysis impossible. However, there are some indications, that hydraulic fracturing in granite in tectonically active regions like the Upper Rhine Graben results in comparatively stronger, perceptible seismicity compared to hydraulic fracturing in the sedimentary rocks of the North German basin. The maximum magnitudes of induced earthquakes caused by hydraulic fracturing of deep geothermal wells in Germany are

  1. GPS-corrected and GIS-based remapping of the Kalahari Gemsbok National Park and the adjacent area in Botswana

    J. du P. Bothma

    1993-09-01

    Full Text Available GPS-equipment was used to map the interior roads, major pans and the location of all windmills and solar-equipped boreholes in the Kalahari Gemsbok National Park and the adjacent areas of Botswana. The final map was generated with GIS-equipment, and supplies managers and planners with the first error-free map of the area. The major errors of previous maps are indicated.

  2. Conodont and Radiolarian Data from the De Long Mountains Quadrangle and Adjacent Areas, Northern Alaska

    Dumoulin, Julie A.; Harris, Anita G.; Blome, Charles D.; Young, Lorne E.

    2006-01-01

    INTRODUCTION This report presents biostratigraphic data from 289 collections at 189 localities in the De Long Mountains, Misheguk Mountain, and Noatak quadrangles (fig. 1); most of these data have never been previously published. The collections were made during studies of the Red Dog massive sulfide deposit in 1998?2004 and in support of regional mapping projects in 1979, 1981, 1983, and 1997?98. The collections?mostly conodonts and some radiolarians?tightly constrain the age of many stratigraphic units of Devonian through Triassic age exposed within the study area, and provide additional data on the depositional environments and thermal history of these rocks. The data are presented in a series of tables, organized by fossil type, stratigraphic unit, and location. Tables 1?12 contain conodont data, mostly from the De Long Mountains quadrangle. All of these collections were initially examined, or were reevaluated, from 1997 through 2004, and complete faunal lists are given for all samples. Table 13 lists ages and conodont color alteration indices (CAIs) of 27 collections from 24 localities in the Noatak quadrangle; updated faunal lists were not prepared for these samples. Radiolarian data?all from the De Long Mountains quadrangle?are given in table 14; these collections were analyzed between 1998 and 2003. Collection localities are shown in four maps (sheets 1, 2). Map 1 (sheet 1) shows all outcrop samples from the De Long Mountains and western Misheguk Mountain quadrangle (locs. 1-121). Maps 2?4 (sheets 1, 2) show all drill hole sample localities; samples come from the Su-Lik deposit and in and around the Anarraaq deposit (map 2, locs. 122?135), in and adjacent to the Red Dog deposits (Paalaaq, Aqqaluk, Main, and Qanaiyaq) (map 3, locs. 136?158), and from drill holes along the Port Road in the Noatak quadrangle (map 4, locs. 159?160). Map 4 (sheet 2) also shows all outcrop samples from the Noatak quadrangle (locs. 161?189). The text summarizes the lithofacies

  3. Groundwater storage changes in the Tibetan Plateau and adjacent areas revealed from GRACE satellite gravity data

    Xiang, Longwei; Wang, Hansheng; Steffen, Holger; Wu, Patrick; Jia, Lulu; Jiang, Liming; Shen, Qiang

    2016-09-01

    Understanding groundwater storage (GWS) changes is vital to the utilization and control of water resources in the Tibetan Plateau. However, well level observations are rare in this big area, and reliable hydrology models including GWS are not available. We use hydro-geodesy to quantitate GWS changes in the Tibetan Plateau and surroundings from 2003 to 2009 using a combined analysis of satellite gravity and satellite altimetry data, hydrology models as well as a model of glacial isostatic adjustment (GIA). Release-5 GRACE gravity data are jointly used in a mascon fitting method to estimate the terrestrial water storage (TWS) changes during the period, from which the hydrology contributions and the GIA effects are effectively deducted to give the estimates of GWS changes for 12 selected regions of interest. The hydrology contributions are carefully calculated from glaciers and lakes by ICESat-1 satellite altimetry data, permafrost degradation by an Active-Layer Depth (ALD) model, soil moisture and snow water equivalent by multiple hydrology models, and the GIA effects are calculated with the new ICE-6G_C (VM5a) model. Taking into account the measurement errors and the variability of the models, the uncertainties are rigorously estimated for the TWS changes, the hydrology contributions (including GWS changes) and the GIA effect. For the first time, we show explicitly separated GWS changes in the Tibetan Plateau and adjacent areas except for those to the south of the Himalayas. We find increasing trend rates for eight basins: + 2.46 ± 2.24 Gt/yr for the Jinsha River basin, + 1.77 ± 2.09 Gt/yr for the Nujiang-Lancangjiang Rivers Source Region, + 1.86 ± 1.69 Gt/yr for the Yangtze River Source Region, + 1.14 ± 1.39 Gt/yr for the Yellow River Source Region, + 1.52 ± 0.95 Gt/yr for the Qaidam basin, + 1.66 ± 1.52 Gt/yr for the central Qiangtang Nature Reserve, + 5.37 ± 2.17 Gt/yr for the Upper Indus basin and + 2.77 ± 0.99 Gt/yr for the Aksu River basin. All these

  4. Microbial biomass and basal respiration of selected Sub-Antarctic and Antarctic soils in the areas of some Russian polar stations

    Abakumov, E.; Mukhametova, N.

    2014-07-01

    Antarctica is a unique place for soil, biological, and ecological investigations. Soils of Antarctica have been studied intensively during the last century, when different national Antarctic expeditions visited the sixth continent with the aim of investigating nature and the environment. Antarctic investigations are comprised of field surveys mainly in the terrestrial landscapes, where the polar stations of different countries are situated. That is why the main and most detailed soil surveys were conducted in the McMurdo Valleys, Transantarctic Mountains, South Shetland Islands, Larsemann Hills and the Schirmacher Oasis. Our investigations were conducted during the 53rd and 55th Russian Antarctic expeditions in the base of soil pits, and samples were collected in Sub-Antarctic and Antarctic regions. Sub-Antarctic or maritime landscapes are considered to be very different from Antarctic landscapes due to differing climatic and geogenic conditions. Soils of diverse zonal landscapes were studied with the aim of assessing the microbial biomass level, basal respiration rates and metabolic activity of microbial communities. This investigation shows that Antarctic soils are quite diverse in profile organization and carbon content. In general, Sub-Antarctic soils are characterized by more developed humus (sod) organo-mineral horizons as well as by an upper organic layer. The most developed organic layers were revealed in peat soils of King George Island, where its thickness reach, in some cases, was 80 cm. These soils as well as soils formed under guano are characterized by the highest amount of total organic carbon (TOC), between 7.22 and 33.70%. Coastal and continental Antarctic soils exhibit less developed Leptosols, Gleysols, Regolith and rare Ornhitosol, with TOC levels between 0.37 and 4.67%. The metabolic ratios and basal respiration were higher in Sub-Antarctic soils than in Antarctic ones, which can be interpreted as a result of higher amounts of fresh organic

  5. 33 CFR 334.1050 - Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of...

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1050 Oakland Outer Harbor adjacent...

  6. Diversity and distribution of Porifera in the bathyal and abyssal Weddell Sea and adjacent areas

    Janussen, Dorte; Tendal, Ole Secher

    2007-08-01

    During the ANDEEP I-III expeditions, we obtained a rich and highly diverse sponge collection from the deep Weddell Sea. All the three Poriferan classes, Calcarea, Demospongiae and Hexactinellida, were well represented. Among this material, we have identified a total of 76 species from 47 genera and 30 families. Of these, 17 species (22%) are new to science and 37 (49%) new for the Southern Ocean. Particularly remarkable is the considerable depth of the boundary between bathyal and abyssal sponge faunas. Both Demospongiae and Hexactinellida show a strong shift in their taxonomic composition from a typical shelf assemblage to a more cosmopolitan deep-sea fauna at around 2500 m. Within the Demospongiae, the families Polymastiidae and Cladorhizidae (carnivorous sponges) are particularly abundant and very diverse. The Calcarea are recorded for the first time from the Antarctic deep sea. The type of sampling gear used, especially the epibenthic sledge, was an important factor for the successful collection of deep-sea sponges during the ANDEEP campaigns.

  7. TIDAL FEATURES IN THE CHINA SEAS AND THEIR ADJACENT SEA AREAS AS DERIVED FROM TOPEX/POSEIDON ALTIMETER DATA

    胡建宇; HiroshiKAWAMURA; 洪华生; FumiakiKOBASHI; 谢强

    2001-01-01

    Some important tidal features of 8 major tidal constituents (M2, S2, K1, O1, P1,Sa, N2 and K2 ) in the china Seas and their adjacent sea areas were obtained using six years' TOPEX/POSEIDON altimeter data. The results showed that the obtained co-tidal and co-range charts for these major tidal constituents agreed well with those of previous researches using observational data from coastal tidal gauge stations and numerical models.

  8. Records of selected wells and lithologic logs of test holes, Hendry County and adjacent areas, Florida

    Fish, John E.; Causaras, Carmen R.; O'Donnell, T. H.

    1983-01-01

    To provide water-resource information for Hendry County, Florida , geologic test holes were drilled in the surficial aquifer, and an extensive inventory was compiled of wells in the surficial aquifer and deep artesian aquifers. This report provides: (1) records for 788 selected wells and test holes including location , construction, water use, water level, chloride concentration, specific conductance, temperature, yield, hydrogen sulfide, and iron-staining problems; and (2) lithologic logs for 26 test holes ranging in depth from 90 to 650 feet. A few inventoried wells and two test holes are in adjacent parts of Collier or Glades Counties. (USGS)

  9. Patterns of use of the Mar Chiquita lagoon (Buenos Aires, Argentina) and adjacent coastal area by fish early life stages.

    Bruno, Daniel O.

    2014-01-01

    The role of the Mar Chiquita lagoon and its adjacent coastal area as nursery ground for fish larvae and juveniles and the factors which regulate their recruitment process, was evaluated. To do so, we analyzed the fish early life stages composition and spatio-temporal variation over the marine-estuarine gradient of the lagoon and its relationship with environmental factors; the diel variation of these stages in the immediate area at the mouth of the lagoon; and the source of the organic carbon...

  10. Relationship between Crustal 3D Density Structure and the Earthquakes in the Longmenshan Range and Adjacent Areas

    ZHANG Jisheng; GAO Rui; ZENG Lingsen; LI Qiusheng; GUAN Ye; HE Rizheng; WANG Haiyan; LU Zhanwu

    2009-01-01

    This paper presents the 3D density structure of crust in the Longmenshan range and adjacent areas, with constraints from seismic and density data. The density structure of crust shows that the immense boundary plane of density distribution in relation to the Longmeshan fault belt is extended downward to -80 km deep. This density boundary plane dips towards the northwest and crosses the Moho. With the proximity to the Longmenshan fault belt, it has a larger magnitude of undulation in the upper and middle crust levels. Density changes abruptly across Longmeshan fault belt. Seismic data show that most of the earthquakes in the Longmenshan area after the 2008 Ms8.0 Wenchuan Earthquake occurred within the upper to middle crust. These earthquakes are clearly distributed in the uplifted region of the basement. A few of them occurs in the transitional zone between the uplifted and subsided areas. But most of the earthquakes distributes in transitional zone from subsided to uplifted areas in the upper and middle crust where relatively large density changes occurr The 3D density structure of crust in the Longmenshan and adjacent areas can thus help us to understand the pattern of overthrusting from the standpoint of deep crust and where the earthquakes occurred.

  11. Carbonate Platform Margin Slope Characteristics of Cambrian Chefu Age in Baojing-Fenghuang and Adjacent Areas, Western Hunan, China

    2003-01-01

    The Cambrian paleogeography in south China can be divided into Yangtze platform, platform margin slope (including upper slope and lower slope) and basin. The carbonate gravity deposits are well developed there, particularly in the Yangtze platform adjacent areas. This paper mainly deals with declivity fan characters of the Chefu age in Fenghuang adjacent areas, western Hunan Province. According to their distribution and thickness, three main declivity fans have been divided in the study areas,namely, Dama ( ∈ c-dsf), Machong ( ∈ c-msf) and Huangheyuan ( ∈ c-hsf) declivity fans. Each fan's characters are described in detail in this paper. Based on their distribution range, scale and fossiliferous layers, two peak periods (fair developmental period) are distinguished: (1) Linguagnostus reconditus Zone (time), and (2) Glyptagnostus reticulatus Zone (time). They were characterized by huge thick limestone breccia layers (single layer 3-4 rn thick) and closely spaced spread. Besides, there are also two developmental periods: (1) Lejopyge laevigata- Proagnostus bulbus Zone (time), and (2) Agnostus inexpectans-Proceratopyge protracta Zone (time) to Erixanium Zone (time) to Corynexochus plumula-Sinoproceratopyge cf. kiangshanensis Zone (time), while Glyptagnostus stolidotus Zone (time) was an interstitial period (without or rare limestone breccias). All these features may verify the relative movement of the earth crust and paleoclimate variety of the Chefu age in the study areas.

  12. Favorable areas for prospecting adjacent to the Roberts Mountains thrust in southern Lander County, Nevada

    Stewart, John Harris; McKee, Edwin H.

    1968-01-01

    Recent geologic mapping by the U.S. Geological Survey of more than 2,500 square miles of a relatively little-studied part of central Nevada has outlined four areas favorable for the discovery of metallic mineral deposits. In these areas, lower Paleozoic carbonate rocks crop out below the Roberts Mountains thrust, a widespread fault in central and north-central Nevada. These areas have a stratigraphic and structural setting similar to that of the areas where large, open-pit gold deposits have been discovered recently at Carlin and Cortez in north-central Nevada.

  13. Biostratigraphy of Triassic Marine Reptiles in Southwest Guizhou and Its Adjacent Area

    2001-01-01

    This paper briefly reviews the Triassic marine reptile fossils inGuizhou Province, especially the fossils that have been recently found in the Guanling area. Based on three sections at Guanling and Xingyi, Guizhou Province and Luoping, Yunnan Province, four horizons with vertebrate fossils are recognized in the Middle and Upper Triassic of this area; They are from bottom to top: Member I and Member Ⅱ of the Guanling Formation, and the Zhuganpo Member and the Wayao Member of the Falang Formation.

  14. Evaluation of low-temperature geothermal potential in Utah and Goshen Valleys and adjacent areas, Utah. Part I. Gravity survey

    Davis, D.A.; Cook, K.L.

    1983-04-01

    During 1980 and 1981 a total of 569 new gravity stations were taken in Utah and Goshen Valleys and adjacent areas, Utah. The new stations were combined with 530 other gravity stations taken in previous surveys which resulted in a compilation of 1099 stations which were used in this study. The additional surveys were undertaken to assist in the evaluation of the area for the possible development of geothermal resources by providing an interpreted structural framework by delineating faults, structural trends, intrusions, thickness of valley fill, and increased density of host rock. The gravity data are presented as (1) a complete Bouguer gravity anomaly map with a 2 mgal contour interval on a scale of 1:100,000 and (2) five generally east-trending gravity profiles. A geologic interpretation of the study area was made from the gravity map and from the interpretive geologic cross sections which were modeled along the gravity profiles.

  15. Geology of the area adjacent to the Free Enterprise uranium-silver Mine, Boulder District, Jefferson County, Montana

    Roberts, W.A.; Gude, A.J.

    1952-01-01

    Uranium minerals.occur in pods associated with cryptocrystalline silica, silver minerals, and scattered sulfide mineral grains in a hydrothermal vein that cuts quartz monzonite and alaskite at the Free Enterprise mine, 2 miles west of Boulder, Mont. The Free Enterprise vein is one of many silicified reef-like structures in this area, most of which trend about N. 60° E. The cryptocrystalline silica zones of the area are lenticular and are bordered by an altered zone where quartz monzonite is the wall rock. No alteration was noticed where alaskite is adjacent to silica zones. No uranium minerals were observed at the surface, but radioactivity anomalies were noted at 57 outcrops. Underground mining has shown that leaching by downward percolating waters has removed most of the uranium from the near-surface part of the Free Enterprise vein and probably has enriched slightly, parts of the vein and the adjacent wall rock from the bottom of the leached zone to the ground-water level. It is possible that other veins that show low to moderate radioactivity at the surface may contain significant concentrations of uranium minerals at relatively shallow depth. The quartz monzonite appears to be a more favorable host rock for the cryptocrystalline silica and associated uranium minerals than the alaskite. The alaskite occurs as vertical_dikes plug-like masses, and as irregularly shaped, gently dipping masses that are believed to have been intruded into open fractures formed during the cooling of the quartz monzonite.

  16. Variability of community interaction networks in marine reserves and adjacent exploited areas

    Montano-Moctezuma, G.; Li, H.W.; Rossignol, P.A.

    2008-01-01

    Regional and small-scale local oceanographic conditions can lead to high variability in community structure even among similar habitats. Communities with identical species composition can depict distinct networks due to different levels of disturbance as well as physical and biological processes. In this study we reconstruct community networks in four different areas off the Oregon Coast by matching simulated communities with observed dynamics. We compared reserves with harvested areas. Simulations suggested that different community networks, but with the same species composition, can represent each study site. Differences were found in predator-prey interactions as well as non-predatory interactions between community members. In addition, each site can be represented as a set of models, creating alternative stages among sites. The set of alternative models that characterize each study area depicts a sequence of functional responses where each specific model or interaction structure creates different species composition patterns. Different management practices, either in the past or of the present, may lead to alternative communities. Our findings suggest that management strategies should be analyzed at a community level that considers the possible consequences of shifting from one community scenario to another. This analysis provides a novel conceptual framework to assess the consequences of different management options for ecological communities. ?? 2008 Elsevier B.V. All rights reserved.

  17. 21st Century Trends in Antarctic Temperature and Polar Stratospheric Cloud (PSC) Area in the GEOS Chemistry-Climate Model

    Hurwitz, M. M.; Newman, P. A.

    2010-01-01

    This study examines trends in Antarctic temperature and APSC, a temperature proxy for the area of polar stratospheric clouds, in an ensemble of Goddard Earth Observing System (GEOS) chemistry-climate model (CCM) simulations of the 21st century. A selection of greenhouse gas, ozone-depleting substance, and sea surface temperature scenarios is used to test the trend sensitivity to these parameters. One scenario is used to compare temperature trends in two versions of the GEOS CCM. An extended austral winter season is examined in detail. In May, June, and July, the expected future increase in CO2-related radiative cooling drives temperature trends in the Antarctic lower stratosphere. At 50 hPa, a 1.3 K cooling is expected between 2000 and 2100. Ozone levels increase, despite this robust cooling signal and the consequent increase in APSC, suggesting the enhancement of stratospheric transport in future. In the lower stratosphere, the choice of climate change scenarios does not affect the magnitude of the early winter cooling. Midwinter temperature trends are generally small. In October, APSC trends have the same sign as the prescribed halogen trends. That is, there are negative APSC trends in "grealistic future" simulations, where halogen loading decreases in accordance with the Montreal Protocol and CO2 continues to increase. In these simulations, the speed of ozone recovery is not influenced by either the choice of sea surface temperature and greenhouse gas scenarios or by the model version.

  18. Survey of roadside alien plants in Hawai`i Volcanoes National Park and adjacent residential areas 2001-2005

    Bio, Keali'i F.; Pratt, Linda W.; Jacobi, James D.

    2012-01-01

    The sides of all paved roads of Hawai`i Volcanoes National Park (HAVO) were surveyed on foot in 2001 to 2005, and the roadside presence of 240 target invasive and potentially invasive alien plant species was recorded in mile-long increments. Buffer zones 5–10 miles (8–16 km) long along Highway 11 on either side of the Kīlauea and Kahuku Units of the park, as well as Wright Road that passed by the disjunct `Ōla`a Tract Unit, were included in the survey. Highway 11 is the primary road through the park and a major island thoroughfare. Three residential subdivisions adjacent to the park were similarly surveyed in 0.5–1 mile (0.8–1.6 km) intervals in 2003, and data were analyzed separately. Two roads to the east and northeast were also surveyed, but data from these disjunct areas were analyzed separately from park roads. In total, 174 of the target alien species were observed along HAVO roads and buffers, exclusive of residential areas, and the mean number of target aliens per mile surveyed was 20.6. Highway 11 and its buffer zones had the highest mean number of target alien plants per mile (26.7) of all park roads, and the Mauna Loa Strip Road had the lowest mean (11.7). Segments of Highway 11 adjacent to HAVO and Wright Road next to `Ōla`a Tract had mean numbers of target alien per mile (24–47) higher than those of any internal road. Alien plant frequencies were summarized for each road in HAVO. Fifteen new records of vascular plants for HAVO were observed and collected along park roads. An additional 28 alien plant species not known from HAVO were observed along the buffer segments of Highway 11 adjacent to the park. Within the adjacent residential subdivisions, 65 target alien plant species were sighted along roadsides. At least 15 potentially invasive species not currently found within HAVO were observed along residential roads, and several other species found there have been previously eliminated from the park or controlled to remnant populations

  19. A Numerical Simulation of the Winter-Time Current System in the China Sea and Adjacent Areas

    李荣凤; 曾庆存

    1994-01-01

    The monthly mean circulations in the whole Pacific Ocean are investigated numerically by using a barotropic ocean model with finer horizontal resolutions. The current system in the China Sea and its adjacent areas has been well reproduced. Especially, some warm currents moving windward in winter, such as the South China Sea Warm Current (SCSWC), Taiwan Warm Current (TWO, Yellow Sea Warm Current (YSWC) and Tsushima Warm Current (TsWC) are simulated very well. Numerical results of January show that there exists indeed a so-called "Taiwan-Tsushima-Tsugaru Warm Current System" (TTTWCS) which originates from the area off the southeastern Hainan Island and enters the Pacific Ocean mainly through the Tsugaru Strait in January.

  20. Contribution to the lichen biota of the Stawy Milickie nature reserve and its adjacent area (Lower Silesia, southwestern Poland

    Edyta Kaźmierska

    2016-07-01

    Full Text Available The paper presents the results of lichenological investigations conducted in the eastern part of the Stawy Milickie nature reserve and its buffer zone (Barycz Valley, southwestern Poland. The study area is a famous waterfowl refuge, consisting of several fishpond complexes, together with adjacent forests, meadows, and villages. In total 72 lichen taxa were recorded, growing on bark and branches of trees and shrubs, stumps, wood, soil, and anthropogenic rock substrates (mortar, concrete, bricks, etc.. Six species, namely Evernia prunastri, Flavoparmelia caperata, Hypogymnia tubulosa, Parmelina tiliacea, Physconia distorta, and Pleurosticta acetabulum, are threatened in Poland. As represented by single young thalli, they indicate the recent improvement of environmental conditions. The lichen biota of the study area is typical for the lowland regions of western and southwestern Poland.

  1. Geology of the Stroudsburg quadrangle and Adjacent areas, Pennsylvania--New Jersey

    Epstein, Jack Burton

    1971-01-01

    The Stroudsburg area is within the Valley and Ridge and Great Valley physiographic provinces, Northampton and Monroe Counties, Pennsylvania, and Warren County, New Jersey. The northeast-trending subparallel valleys and ridges resulted from erosion of folded heterogeneous sedimentary rocks. These are Middle Ordovician to Middle Devonian in age and are more than 17,000 feet thick. Deposition of a thick flysch sequence (Martinsburg Formation of Ordovician age) accompanied onset of Taconic orogenesis. It was followed by deposition of a thick molasse sequence of Silurian and Early Devonian age (continental and marginal-marine clastics--Shawangunk Formation and Bloomsburg Red Beds--overlain by predominantly marginal-marine and subtidal limestone, dolomite, shale, and sandstone--Poxono Island Formation through Oriskany Group). Basin deepening and gradual shallowing occurred during Esopus through Mahantango deposition, heralding the Acadian clastic wedge exposed north of the Stroudsburg area. Interpretation of sedimentary structures and regional stratigraphic relations suggest that the Silurian and Devonian rocks were deposited in the following environments: A1luviated coastal plain (meandering and braided streams), tidal flats (supratidal and intertidal), barrier zone, and neritic zone (upper and lower). The rock stratigraphic units have been grouped into four lithotectonic units, each having a different style of deformation. Folds produced in these rocks are disharmonic, and it is believed that each rock sequence is set off from units above and below by decollements, or zones of detachment. Movement was northwest into the Appalachian basin, primarily by gravitational sliding. The contact between the Shawangunk Formation of Silurian age and Martinsburg Formation of Ordovician age, is one zone of detachment as well as an angular unconformity. Deformational effects of the Middle to Late Ordovician Taconic orogeny are elusive, but it appears that the folds and most minor

  2. Peat wetland as a natural filter of effluents from adjacent industrial areas

    József DEZSO

    2015-12-01

    Full Text Available The main objective of the project is the study of a peat wetland functioning as recipient of effluents from former and present-day industrial activities. The investigation was focused on heavy metal contaminations and their probable mobilization or fixation. The studied peatbog is a typical Eastern European wetland, located in Hungary on the border between medium mountains (Bakony Mountains and a Neogene basin (the Sárrét, an area under nature conservation. Watercourses and prevailing air currents can transport contaminants from industrial areas to the wetland. At first the basic parameters of surface waters and subsurface conditions (soils, groundwater were investigated. These parameters (EC, Cl are possible indicators of contamination. Subsequently, the amounts of heavy metals (Cd, Pb extracted by solution in two steps (HCl, CaCl2 were measured using atomic absorption spectroscopy (AAS. The extracted values indicate what amounts of which elements could be mobilized by human impact and/or production of humic acids, which occasionally emerges during the remediation works. The total heavy metal concentrations in the samples were investigated by X-ray fluorescence method. Based on the investigation, the peatbog is claimed to function as a natural filter.

  3. Flood hazards in the Seattle-Tacoma urban complex and adjacent areas, Washington

    Foxworthy, B.L.; Nassar, E.G.

    1975-01-01

    Floods are natural hazards that have complicated man's land-use planning for as long as we have had a history. Although flood hzards are a continuing danger, the year-to-year threat cannot be accurately predicted. Also, on any one stream, the time since the last destructive flood might be so long that most people now living near the stream have not experienced such a flood. Because of the unpredictability and common infrequency of disastrous flooding, or out of ignorance about the danger, or perhaps because of an urge to gamble, man tends to focus his attention on only the advantages of the flood-prone areas, rather than the risk due to the occasional major flood. The purposes of this report are to: (1) briefly describe flood hazards in this region, including some that may be unique to the Puget Sound basin, (2) indicate the parts of the area for which flood-hazard data are available, and (3) list the main sources of hydrologic information that is useful for flood-hazard analysis in conjuction with long-range planning. This map-type report is one of a series being prepared by the U.S. Geological Survey to present basic environmental information and interpretations to assist land-use planning in the Puget Sound region.

  4. Structure and evolution of Middle Permian palaeo-seamounts in Bayan Har and its adjacent area

    WANG Yongbiao

    2005-01-01

    Middle Permian palaeo-seamounts in the area of Bayan Har are generally composed of volcanic basement and carbonate cap. Basaltic lava, volcanic breecia and polymictic breccia can be identified as the main kinds of rock in the basement of palaeo-seamounts. Massive bioclastic limestone and reef framestone formed the carbonate cap of the palaeo-sea- mounts. The contact relationship between carbonate cap and volcanic basement is a kind of conformity or depositional unconformity. Study of the structure and petrology of palaeo-sea- mounts suggests that the evolution history of the palaeo-seamounts in this area can be divided into five stages at least. They are the origin of the first volcanic basement, the formation of the first carbonate cap, the breaking of the first carbonate cap by renewed volcanism, the deposition of red calcareous mudstone and the rebuilding of the second carbonate cap at last. In one of the palaeo-seamounts, volcanic activation took place even after the reconstruction of the second carbonate cap. Lots of fusulinid fossils, such as Neoschwagerina craticulifera Schwager, Schwagerina sp. and Verbeekina sp., were found both in the carbonate cap and volcanic basement, showing that the palaeo-seamounts were originated and developed within the Maokou stage of Middle Permian.

  5. Reclamation by tubewell drainage in Rechna Doab and adjacent areas, Punjab region, Pakistan

    Malmberg, Glenn T.

    1975-01-01

    Around the turn of the century, a network of more than 40,000 miles of canals was constructed to divert water from the Indus River and its tributaries to about 23 million acres of largely unused desert in the Punjab region of Pakistan. The favorable climate and the perennial supply of irrigation water made available through the canals instituted the beginning of intensive farming. However, because of generally poor drainage and the high rate of canal leakage, the water table began to rise. As the population increased and agriculture expanded, the demand for irrigation water soon exceeded the available supply. Spreading of the canal supply to meet the expanded needs locally created shortages that prevented adequate leaching. Increased evaporation from the rising water table further contributed to the progressive accumulation of soluble salts in the soil. By the late 1930's the combined effect of waterlogging and salinity had reduced the agricultural productivity of the region to one of the lowest in the world. In 1954, after several unsuccessful projects were undertaken to reclaim affected areas and to stop the progressive encroachment of waterlogging and salinization, the Government of Pakistan in cooperation with the U.S. International Cooperation Administration undertook a study of the geology and hydrology of the Indus Plain that ultimately resulted in the formulation of a ground-water reclamation program. The principal feature of the program is the utilization of a network of deep wells spaced about a mile apart for the dual purpose of lowering the water table and for providing supplemental irrigation water. Through financial assistance and technical and engineering support principally from the United States, construction began in 1960 on the first of 18 proposed reclamation projects that eventually will include 21 million acres and more than 28,000 wells having an installed capacity of more than 100,000 cubic feet per second. An area of about 1.3 million acres

  6. Ancient buried valleys in the city of Tallinn and adjacent area

    Vaher, Rein

    2010-03-01

    Full Text Available The distribution, morphology, fillings, and origin of buried valleys are discussed. The direction of the valleys varies from NW to NE. Within the Viru-Harju Plateau the valleys have a more or less symmetric profile, but asymmetric profiles are dominating in the pre-klint area. They are mainly filled with glacial (till, glaciofluvial (sand, gravel, and pebbles, glacio­lacustrine (varved clay, and marine (fine-grained sand deposits. The Tallinn valley with its tributary valleys (Saku and Sausti and fore-klint branches (Harku, Lilleküla, and Kadriorg looks like a river system. The fore-klint branches extend over 20 km in the Gulf of Finland. They are probably tributaries of the ancient river Pra-Neva. Most likely, the formation of valleys was continuous, starting from pre-Quaternary river erosion, and was sculptured by variable processes during the ice ages and influenced by flowing water during the interglacial periods.

  7. Mammals in the areas adjacent to Forsmark and Oskarshamn. Population density, ecological data and carbon budget

    Truve, Johan; Cederlund, Goeran [Svensk Naturfoervaltning AB, Ramsberg (Sweden)

    2005-06-01

    The Swedish Nuclear Fuel and Waste Management Co is in the process of selecting a safe and environmentally acceptable location for the deep-level repository of radioactive waste. SKB has expressed the importance of monitoring mammal species that are of interest both in biodiversity issues and for local hunting and recreational purposes. Two of the major goals are to: 1) monitor dynamics of population density over several years; 2) obtain information that is essential for modelling of energy/carbon flows in the biosphere and ultimately calculations of the risks of exposure to radionuclides. This report contributes to the major goals by presenting: Results from surveys of mammal abundance in the study sites near Forsmark and Oskarshamn, and a comparison with data from other surveys. A summary of traits associated to demography, resource selection and spatial distribution. A model framework that can be used to model the future development of populations. A plausible future scenario for mammal species. Mammal contribution to fluxes of energy and material in the ecosystem. Estimated harvest rates of mammals in the study sites. General conclusions that can be drawn from the survey are that population densities of the most common species are in the same range as many other populations. Lynx, wild boar, red deer and fallow deer are expanding in the areas. Marine mammals have not been surveyed but at least grey seals are important top consumers in the coastal ecosystem. Red listed species resident in the areas are Lynx, Otter, Whiskered bat, Natterer's bat, Nathusius' pipistrelle and Harbour seal. Annual production of the mammal species that were surveyed was 40-50 mg carbon/m2 and year. Hunters harvest nearly half of the production each year. Future developments for the populations are briefly discussed and a model framework that can be used to make better quantitative predictions is presented.

  8. SIR2012-5282 Surficial Geology: Hydrogeology of the Susquehanna River valley-fill aquifer system and adjacent areas in eastern Broome and southeastern Chenango Counties, New York

    U.S. Geological Survey, Department of the Interior — The hydrogeology of the valley-fill aquifer system along a 32-mile reach of the Susquehanna River valley and adjacent areas was evaluated in eastern Broome and...

  9. Preliminary research to determine stress districts from focal mechanism solutions in Southwest China and its adjacent area

    1999-01-01

    The method of sliding direction fitting is used to determine stress districts, taking the shear stress directions and ratios of shear stress to stress on fault planes given by focal mechanism solutions as the criteria to select focal mechanism solutions of one region and sorting out the earthquakes controlled by different tectonic stress fields, and then determining the stress districts from epicenter distribution of earthquakes. We call this method as step by step convergence method. By inversion analyzing of 297 focal mechanism solutions, we consider that Southwest China and its adjacent area can be divided into 5 stress districts, and we worked out directions of the three principal stresses and values of shape factor φin 5 stress districts.

  10. Analysis of sea surface temperature fronts in the Taiwan Strait and its adjacent area using an advanced edge detection method

    2010-01-01

    A morphology-based edge detection method has been used to study sea surface temperature (SST) fronts in the Taiwan Strait and its adjacent area. The method is based on mathematical morphology with multi-dimensional and multi-structural elements. Using six years’ SST data from September 2002 to August 2008, we distinguished the large SST front like Kuroshio Front as well as the smaller ones: namely Taiwan Bank Front, Zhe-Min Coastal Front and Zhang-Yun Ridge Front. The seasonal and monthly variations of these fronts were also studied. Generally, the SST fronts are stronger in winter but weaker in summer. And the fronts are at their active stage during the period from January to May but at their declining stage during the period from July to October.

  11. Annotated bibliography of the geology of the Columbia Plateau (Columbia River Basalt) and adjacent areas of Oregon

    Bela, J.

    1979-01-01

    This bibliography containing approximately 2000 entries was prepared by the Oregon Department of Geology and Mineral Industries under Subcontract SA-913 with Rockwell Hanford Operations' Basalt Waste Isolation Program. The objective of the Basalt Waste Isolation Program is to determine the feasibility of storing nuclear waste within the Columbia River Basalt Group. Under the geologic portion of this program, the stratigraphic, structural, tectonic, seismic, and hydrologic aspects of the Columbia Plateau are being examined. Other aspects of the Basalt Waste Isolation Program are concerned with systems integration, engineered barriers, engineering testing, and construction of a near-surface test facility. The area covered in this bibliography comprises that area north of 43/sup 0/30' latitude and east of the Willamette Meridian, which is located just west of Portland. The bibliographic entries are presented in two forms. The first is an alphabetized listing of all articles dealing with the geology of the Columbia Plateau (Columbia River Basalt) and adjacent areas of Oregon. The second form consists of an alphabetized listing of the entries subdivided under fourteen categories. (RWR)

  12. Nitrous oxide in the Changjiang (Yangtze River Estuary and its adjacent marine area: Riverine input, sediment release and atmospheric fluxes

    G.-L. Zhang

    2010-11-01

    Full Text Available Dissolved nitrous oxide (N2O was measured in the waters of the Changjiang (Yangtze River Estuary and its adjacent marine area during five surveys covering the period of 2002–2006. Dissolved N2O concentrations ranged from 6.04 to 21.3 nM, and indicate great temporal and spatial variations. Distribution of N2O in the Changjiang Estuary was influenced by multiple factors and the key factor varied between cruises. Dissolved riverine N2O was observed monthly at station Xuliujing of the Changjiang, and ranged from 12.4 to 33.3 nM with an average of 19.4 ± 7.3 nM. N2O concentrations in the river waters showed obvious seasonal variations with higher values occurring in both summer and winter. Annual input of N2O from the Changjiang to the estuary was estimated to be 15.0 × 106 mol/yr. N2O emission rates from the sediments of the Changjiang Estuary in spring ranged from −1.88 to 2.02 μmol m−2 d−1, which suggests that sediment can act as either a source or a sink of N2O in the Changjiang Estuary. Average annual sea-to-air N2O fluxes from the studied area were estimated to be 7.7 ± 5.5, 15.1 ± 10.8 and 17.0 ± 12.6 μmol m−2d−1 using LM86, W92 and RC01 relationships, respectively. Hence the Changjiang Estuary and its adjacent marine area are a net source of atmospheric N2O.

  13. A Biophysical and Economic Profile of South Georgia and the South Sandwich Islands as Potential Large-Scale Antarctic Protected Areas.

    Rogers, Alex D; Yesson, Christopher; Gravestock, Pippa

    2015-01-01

    The current hiatus in the establishment of a network of marine protected areas (MPAs) in the Antarctic means that other routes to conservation are required. The protection of overseas territories in the Antarctic and sub-Antarctic represents one way to advance the initiation of such a network. This review of the physical and biological features of the United Kingdom (U.K.) overseas territories of South Georgia and South Sandwich Islands (SGSSI) is undertaken to estimate the importance of the islands in terms of marine conservation in the Southern Ocean and globally. The economy and management of SGSSI are also analysed, and the question of whether the islands already have sufficient protection to constitute part of an Antarctic network of MPAs is assessed. The SGSSI comprise unique geological and physical features, a diverse marine biota, including a significant proportion of endemic species and globally important breeding populations of marine predators. Regardless of past exploitation of biotic resources, such as seals, whales and finfish, SGSSI would make a significant contribution to biological diversity in an Antarctic network of MPAs. At present, conservation measures do not adequately protect all of the biological features that render the islands so important in terms of conservation at a regional and global level. However, a general lack of data on Antarctic marine ecosystems (particularly needed for SGSSSI) makes it difficult to assess this fully. One barrier to achieving more complete protection is the continuing emphasis on fishing effort in these waters by U.K. government. Other non-U.K. Antarctic overseas territories of conservation importance are also compromised as MPAs because of the exploitation of fisheries resources in their waters. The possible non-use values of SGSSI as well as the importance of ecosystem services that are indirectly used by people are outlined in this review. Technology is improving the potential for management of remote MPAs

  14. Radon and its decay product activities in the magmatic area and the adjacent volcano-sedimentary Intrasudetic Basin

    D. Tchorz

    2007-06-01

    Full Text Available In the magmatic area of Sudetes covering the Karkonosze granite and adjacent volcano-sedimentary Intrasudetic Basin a study of atmospheric radon activity was performed by means of SSNTD Kodak LR-115. The study was completed by gamma spectrometric survey of eU and eTh determined by gamma activity of radon decay products 214Bi and 208Tl respectively. In the case of the western part of the Karkonosze granite area the radon decay products activity in the granitic basement was found to be as high as 343 Bq/kg for 214Bi and 496 Bq/kg for 208Tl respectively. Atmospheric radon content measured by means of Kodak LR115 track detector at the height of 1.5 m was found as high as 70 Bq/m3 in the regions, where no mining activities took place. However in the eastern part of the granitic massif in the proximity of abandoned uranium mine atmospheric radon content was found to be 6000 Bq/m3. In the case of sedimentary basin where sedimentary sequence of Carboniferous rocks has been penetrated by younger gases and fluids of volcanic origin uranium mineralization developed. The region known from its CO2 outburst during coal mining activity is characterized by good ventilation of the uranium enriched geological basement resulting in increased atmospheric radon activity being in average 72 Bq/m3. In the vicinity of coal mine tailing an increase up to 125 Bq/m3 can be observed. Seasonal variations of atmospheric radon content are influenced in agricultural areas by cyclic cultivation works (plough on soils of increased uranium content and in the case of post-industrial brownfields varying rates of radon exhalation from tailings due to different meteorological conditions.

  15. Landscape mapping at sub-Antarctic South Georgia provides a protocol for underpinning large-scale marine protected areas

    Hogg, Oliver T.; Huvenne, Veerle A. I.; Griffiths, Huw J.; Dorschel, Boris; Linse, Katrin

    2016-10-01

    Global biodiversity is in decline, with the marine environment experiencing significant and increasing anthropogenic pressures. In response marine protected areas (MPAs) have increasingly been adopted as the flagship approach to marine conservation, many covering enormous areas. At present, however, the lack of biological sampling makes prioritising which regions of the ocean to protect, especially over large spatial scales, particularly problematic. Here we present an interdisciplinary approach to marine landscape mapping at the sub-Antarctic island of South Georgia as an effective protocol for underpinning large-scale (105–106  km2) MPA designations. We have developed a new high-resolution (100 m) digital elevation model (DEM) of the region and integrated this DEM with bathymetry-derived parameters, modelled oceanographic data, and satellite primary productivity data. These interdisciplinary datasets were used to apply an objective statistical approach to hierarchically partition and map the benthic environment into physical habitats types. We assess the potential application of physical habitat classifications as proxies for biological structuring and the application of the landscape mapping for informing on marine spatial planning.

  16. Geomorphological dynamics of Deception Island (Maritime Antarctic): a GIS based analysis of the Cerro de la Cruz - Crater Lake area

    Melo, R.; Vieira, G.; Rocha, J.; Caselli, A.; Batista, V.; Ramos, M.

    2009-04-01

    This study, based on field surveying from the austral summer of 2007-2008, presents the first results of the detailed geomorphological mapping of Deception Island (South Shetlands, Antarctic Peninsula). The main objective is to provide new geomorphological observations aiming to understand: i) how climate change is affecting permafrost, ii) the interactions between volcanoes and permafrost and also, iii) the present-day geomorphological dynamics in an area of high environmental sensitivity. The detailed geomorphological mapping was made in the area between the Argentinean base of Decepción and the Spanish Base Gabriel de Castilla, corresponding to 4 km2, as well as in the vicinity of the ruins of the Chilean Refuge. Mapping focused on landforms and deposits that may be indicators of permafrost dynamics, such as rockfalls, gullies, debris flows, thermokarst depressions and lag surfaces. Active layer thickness was monitored during the summer in two sites with different topographic conditions using mechanical probing. The spatial distribution of the geomorphological processes and landforms was studied using a GIS, with the objective to study the controls of several independent variables, such as altitude, aspect, slope, topographical parameters and net summer radiation.

  17. Molecular characterization of sulfate-reducing bacteria community in surface sediments from the adjacent area of Changjiang Estuary

    Zhang, Yu; Zhen, Yu; Mi, Tiezhu; He, Hui; Yu, Zhigang

    2016-02-01

    Sulfate-reducing bacteria (SRB), which obtain energy from dissimilatory sulfate reduction, play a vital role in the carbon and sulfur cycles. The dissimilatory sulfite reductase (Dsr), catalyzing the last step in the sulfate reduction pathway, has been found in all known SRB that have been tested so far. In this study, the diversity of SRB was investigated in the surface sediments from the adjacent area of Changjiang Estuary by PCR amplification, cloning and sequencing of the dissimilatory sulfite reductase beta subunit gene ( dsrB). Based on dsrB clone libraries constructed in this study, diversified SRB were found, represented by 173 unique OTUs. Certain cloned sequences were associated with Desulfobacteraceae, Desulfobulbaceae, and a large fraction (60%) of novel sequences that have deeply branched groups in the dsrB tree, indicating that novel SRB inhabit the surface sediments. In addition, correlations of the SRB assemblages with environmental factors were analyzed by the linear model-based redundancy analysis (RDA). The result revealed that temperature, salinity and the content of TOC were most closely correlated with the SRB communities. More information on SRB community was obtained by applying the utility of UniFrac to published dsrB gene sequences from this study and other 9 different kinds of marine environments. The results demonstrated that there were highly similar SRB genotypes in the marine and estuarine sediments, and that geographic positions and environmental factors influenced the SRB community distribution.

  18. Evidence that local land use practices influence regional climate, vegetation, and stream flow patterns in adjacent natural areas

    Stohlgren, T.J.; Chase, T.N.; Pielke, R.A.; Kittel, T.G.F.; Baron, J.S.

    1998-01-01

    We present evidence that land use practices in the plains of Colorado influence regional climate and vegetation in adjacent natural areas in the Rocky Mountains in predictable ways. Mesoscale climate model simulations using the Colorado State University Regional Atmospheric Modelling System (RAMS) projected that modifications to natural vegetation in the plains, primarily due to agriculture and urbanization, could produce lower summer temperatures in the mountains. We corroborate the RAMS simulations with three independent sets of data: (i) climate records from 16 weather stations, which showed significant trends of decreasing July temperatures in recent decades; (ii) the distribution of seedlings of five dominant conifer species in Rocky Mountain National Park, Colorado, which suggested that cooler, wetter conditions occurred over roughly the same time period; and (iii) increased stream flow, normalized for changes in precipitation, during the summer months in four river basins, which also indicates cooler summer temperatures and lower transpiration at landscape scales. Combined, the mesoscale atmospheric/land-surface model, short-term in regional temperatures, forest distribution changes, and hydrology data indicate that the effects of land use practices on regional climate may overshadow larger-scale temperature changes commonly associated with observed increases in CO2 and other greenhouse gases.

  19. Spring land temperature anomalies in northwestern US and the summer drought over Southern Plains and adjacent areas

    Xue, Yongkang; Oaida, Catalina M.; Diallo, Ismaila; Neelin, J. David; Li, Suosuo; De Sales, Fernando; Gu, Yu; Robinson, David A.; Vasic, Ratko; Yi, Lan

    2016-04-01

    Recurrent drought and associated heatwave episodes are important features of the US climate. Many studies have examined the connection between ocean surface temperature changes and conterminous US droughts. However, remote effects of large-scale land surface temperature variability, over shorter but still considerable distances, on US regional droughts have been largely ignored. The present study combines two types of evidence to address these effects: climate observations and model simulations. Our analysis of observational data shows that springtime land temperature in northwest US is significantly correlated with summer rainfall and surface temperature changes in the US Southern Plains and its adjacent areas. Our model simulations of the 2011 Southern Plains drought using a general circulation model and a regional climate model confirm the observed relationship between land temperature anomaly and drought, and suggest that the long-distance effect of land temperature changes in the northwest US on Southern Plains droughts is probably as large as the more familiar effects of ocean surface temperatures and atmospheric internal variability. We conclude that the cool 2011 springtime climate conditions in the northwest US increased the probability of summer drought and abnormal heat in the Southern Plains. The present study suggests a strong potential for more skillful intra-seasonal predictions of US Southern Plains droughts when such facts as ones presented here are considered.

  20. The inventions in nanotechnological area increase the efficiency of construction, housing and communal services and adjacent economic fields

    VLASOV Vladimir Alexeevich

    2014-10-01

    Full Text Available The review gives brief description of inventions in nanotechnological area: the production method for silver nanoparticles with modified ligand shell in highviscosity matrix (RU 2526967; structures containing molecular structures with high aspect ratio and the production methods for them (RU 2526969; preconcentrator of the samples (RU 2526972; antifrictional composition (RU 2526989; conglutination composition for metal articles (RU 2526991; thin dispersed organic suspension of metal/carbon nanocomposite and the production method for it (RU 2527218; composite ion-exchange membrane (RU 2527236; pigment based on modified titanium dioxide powder (RU 2527262; the method of production of microballs and microspheres (RU 2527427; the method for strengthening metal products with nanostructured surface layers (RU 2527511; the method of production of sensitive element of gas detector with carbon nanotubes (RU 2528032; cutting plate (RU 2528288 etc. The inventions in the nanotechnological area can cause significant effects on construction, housing and communal services and adjacent fields of economy: reduced hardening time and increased durability of adhesive joints, increased wear-resistance of cutting plates, increased strength of materials under compressive forces, descreased detail tearing, etc. For example, composition for glueing metal products (RU 2526991 contains anaerobic mastic AH-111 and the filler – carbon nanotubes «Taunit-M». The invention shortens hardening time and increases the durability of adhesive joints. Cutting plate (RU 2528288 contains the base made of hard alloy and sprayed on it wear-resistant layer of nanostructured tungsten carbide and nanostructured niobium carbide which grain size is 20–50 nm, and their ratio, mass.%: nanostructured tungsten carbide 90, nanostructured niobium carbide – the rest. That increases wear-resistance of cutting plates, especially in hard cutting modes.

  1. Distribution of 222Rn concentration in an inhabited area adjacent to the Aja granitic heights of Hail Province, Saudi Arabia.

    Kinsara, Abdulraheem Abdulrahman; Shabana, El-Said Ibrahim; Abulfaraj, Waleed Hussain; Qutub, Maher Mohammad Taher

    2015-01-01

    Radon-222 has been measured in groundwater, dwellings, and atmosphere of an inhabited area adjacent to the granitic Aja heights of Hail province, Saudi Arabia. The measurements were carried out in the field using a RAD7 instrument. Twenty-eight water samples, collected from drilled wells scattered in the region, were analyzed. Radon-222 concentration ranged from 2.5-95 kBq m(-3) with an average value of about 30.3 kBq m(-3). The higher values were found in wells drawing water from granitic aquifers. Indoor 222Rn was measured in 20 dwellings of rural areas in Hail city and other towns. Concentrations ranged from 12-125.6 Bq m(-3), with an average value of 54.6 Bq m(-3). Outdoor air 222Rn was measured at 16 sites, with values ranging from 6.2-13.3 Bq m(-3), with an average value of 10.5 Bq m(-3). The estimated average effective dose due to inhalation of 222Rn released from water was 0.08 mSv y(-1). The estimated average annual effective dose due to indoor 222Rn was 1.35 mSv, which lies below the effective dose range (3-10 mSv) given as the recommended action level. Based on the average dose rate values, the excess lifetime cancer risk values were estimated as 69.8 × 10(-4) due to indoor radon and 13.4 × 10(-4) due to outdoor radon.

  2. Antarctic clouds

    Lachlan-Cope, Tom

    2010-01-01

    Sensitivity studies with global climate models show that, by their influence on the radiation balance, Antarctic clouds play a major role in the climate system, both directly at high southern latitudes and indirectly globally, as the local circulation changes lead to global teleconnections. Unfortunately, observations of cloud distribution in the Antarctic are limited and often of low quality because of the practical difficulty in observing clouds in the harsh Antarctic environment. The best ...

  3. Characteristics of change of the SST in the tropical western Pacific and the tropical Indian Ocean and its response to the change of the Antarctic ice area

    2000-01-01

    In this paper, by using ocean surface temperature data (COADS), the study is made of the characteristics of the monthly and annual changes of the SST in the tropical western Pacific and Indian Oceans, which have important influences on the climate change of the whole globe and the relation between ENSO(E1 Nino-Southern Oscillation) and the Antarctic ice area is also discussed. The result indicates that in the tropical western Pacific and the Indian Oceans the change of Sea Surface Temperture (SST) is conspicuous both monthly and armaully, and shows different change tendency between them. This result may be due to different relation in the vibration period of SST between the two Oceans. The better corresponding relationship is obvious in the annual change of SST in the tropical Indian Ocean with the occurrence El Nino and LaNlra. The change of the SST in the tropical western Pacific and the tropical Indian Oceans has a close relation to the Antarctic ice area, especially to the ice areas in the eastern-south Pole and Ross Sea, and its notable correlative relationship appears in 16 months when the SST of the tropical western Pacific and the Indian Oceans lag back the Antarctic ice area.

  4. The importance of sea ice area biases in 21st century multimodel projections of Antarctic temperature and precipitation

    Bracegirdle, Thomas J.; Stephenson, David B.; Turner, John; Phillips, Tony

    2015-12-01

    Climate models exhibit large biases in sea ice area (SIA) in their historical simulations. This study explores the impacts of these biases on multimodel uncertainty in Coupled Model Intercomparison Project phase 5 (CMIP5) ensemble projections of 21st century change in Antarctic surface temperature, net precipitation, and SIA. The analysis is based on time slice climatologies in the Representative Concentration Pathway 8.5 future scenario (2070-2099) and historical (1970-1999) simulations across 37 different CMIP5 models. Projected changes in net precipitation, temperature, and SIA are found to be strongly associated with simulated historical mean SIA (e.g., cross-model correlations of r = 0.77, 0.71, and -0.85, respectively). Furthermore, historical SIA bias is found to have a large impact on the simulated ratio between net precipitation response and temperature response. This ratio is smaller in models with smaller-than-observed SIA. These strong emergent relationships on SIA bias could, if found to be physically robust, be exploited to give more precise climate projections for Antarctica.

  5. Antibiotic resistance in Escherichia coli strains isolated from Antarctic bird feces, water from inside a wastewater treatment plant, and seawater samples collected in the Antarctic Treaty area

    Rabbia, Virginia; Bello-Toledo, Helia; Jiménez, Sebastián; Quezada, Mario; Domínguez, Mariana; Vergara, Luis; Gómez-Fuentes, Claudio; Calisto-Ulloa, Nancy; González-Acuña, Daniel; López, Juana; González-Rocha, Gerardo

    2016-06-01

    Antibiotic resistance is a problem of global concern and is frequently associated with human activity. Studying antibiotic resistance in bacteria isolated from pristine environments, such as Antarctica, extends our understanding of these fragile ecosystems. Escherichia coli strains, important fecal indicator bacteria, were isolated on the Fildes Peninsula (which has the strongest human influence in Antarctica), from seawater, bird droppings, and water samples from inside a local wastewater treatment plant. The strains were subjected to molecular typing with pulsed-field gel electrophoresis to determine their genetic relationships, and tested for antibiotic susceptibility with disk diffusion tests for several antibiotic families: β-lactams, quinolones, aminoglycosides, tetracyclines, phenicols, and trimethoprim-sulfonamide. The highest E. coli count in seawater samples was 2400 cfu/100 mL. Only strains isolated from seawater and the wastewater treatment plant showed any genetic relatedness between groups. Strains of both these groups were resistant to β-lactams, aminoglycosides, tetracycline, and trimethoprim-sulfonamide.In contrast, strains from bird feces were susceptible to all the antibiotics tested. We conclude that naturally occurring antibiotic resistance in E. coli strains isolated from Antarctic bird feces is rare and the bacterial antibiotic resistance found in seawater is probably associated with discharged treated wastewater originating from Fildes Peninsula treatment plants.

  6. Seasonal and spatial variability of appendicularian density and taxonomic composition in the Caravelas Estuary (Northeastern Brazil and adjacent coastal area

    Pedro Freitas de Carvalho

    2010-02-01

    Full Text Available This study aimed to identify and assess the seasonal and spatial variations of the appendicularians in the Caravelas River estuary and the adjacent coastal area. Samples were taken during 12 campaigns over five years (2001 and 2003-2006. Ten species were identified; the most abundant were Oikopleura dioica, Oikopleura rufescens, and Oikopleura longicauda. These species represented more than 95% of the total numbers of appendicularians. The remaining species were less frequent and occurred in low densities. The mean density of appendicularians found at the coastal stations (804 ind.m-3. was higher than in the estuary (66 ind.m-3. However, the differences observed between the estuary and coastal stations were not significant (p=0.54. The samples taken during the dry season showed a higher mean density (587 ind.m-3 than in the rainy season (376 ind.m-3, and the differences between the seasons were statistically significant (p=0.004.Esse trabalho teve como objetivo identificar e avaliar as variações espaciais e sazonais das apendiculárias no estuário do rio Caravelas e área costeira adjacente (17º35' - 18º22' S e 39º8' - 39º55'W. As coletas foram realizadas em 12 campanhas durante cinco anos (2001 e 2003 - 2006. Foram identificadas dez espécies, sendo que Oikopleura dioica, O. rufescens e O. longicauda foram as mais abundantes. Estas três espécies representaram mais de 95% do total de apendiculárias coletadas. As outras espécies foram menos freqüentes e ocorreram em baixas densidades. A densidade média de apendiculárias encontrada nas estações e costeiras (804 ind.m-3 foi maior que na de estuário (158 ind.m-3. As diferenças encontradas entre as estações de estuário e costeiras não foram significativas (p=0,73. As campanhas realizadas durante o período seco apresentaram densidade média (587 ind.m-3 maior que do período chuvoso (376 ind.m-3. As diferenças entre os períodos chuvoso e seco foram estatisticamente

  7. 南极特别保护区管理权辨析%The Analysis of Right of Management in Antarctic Specially Protected Areas

    刘惠荣; 陈明慧; 董跃

    2014-01-01

    南极特别保护区是南极条约及其议定书所建立的南极生态环境保护的重要制度。南极特别保护区的管理国依据南极条约协商会议审议通过的管理计划在保护区内行使管理权,以实现对特别保护区的有效管理。通过分析保护区管理权实施的依据及实践,探究潜在的利益博弈,指出在南极“主权冻结”原则持续化的过程中,南极特别保护区内管理权的实施成为相关国家加强在南极实质性存在的有效手段。我国应积极参与到南极特别保护区的设立与管理事务,以切实维护我国在南极的利益。%The establishment of Antarctic Specially Protected Areas (ASPA) is an important means for Antarctic regional protection .A nation which manages ASPA exercises the right of management according to the management plan passed by Antarctic Treaty Consultative Meeting .In this paper ,the authors sum‐marize the practical experience of management in ASPA ,discuss the basis of international law for exerci‐sing the right of management and analyze the potential interest game between different countries in the Antarctic .This paper concludes that the experience of management in ASPA is becoming increasingly im‐portant for strengthening a country's substantial presence in the Antarctic within the restriction of the Ant‐arctic Treaty that freezes the territorial claims .China should take an active part in the establishment and management of ASPA .By this way ,we can better safeguard our own interest in the Antarctic .

  8. Antarctic Fishes.

    Eastman, Joseph T.; DeVries, Arthur L.

    1986-01-01

    Explains the adaptations to Antarctic waters that Notothenioidei, a group of advanced bony fishes, have exhibited. Discusses the fishes' mechanisms of production of antifreeze properties and their capacities for neutral buoyancy in water. (ML)

  9. Radioecology of Vertebrate Animals in the Area Adjacent to the Chernobyl Nuclear Power Plant Site in 1986-2008

    Farfan, E. B.; Gashchak, S. P.; Makliuk, Y. A.; Maksymenko, A. M.; Bondarkov, M. D.; Jannik, G. T.; Marra, J. C.

    2009-12-01

    A widespread environmental contamination of the areas adjacent to the Chernobyl Nuclear Power Plant (ChNPP) site attracted a great deal of publicity to the biological consequences of the ChNPP catastrophe. However, only a few studies focused on a detailed analysis of radioactive contamination of the local wild fauna and most of them were published in Eastern European languages, making them poorly accessible for Western scientists. In addition, evaluation of this information appears difficult due to significant differences in raw data acquisition and analysis methodologies and final data presentation formats. Using an integrated approach to assessment of all available information, the International Radioecology Laboratory scientists showed that the ChNPP accident had increased the average values of the animals 137Cs and 90Sr contamination by a factor of thousands, followed by its decrease by a factor of tens, primarily resulting from a decrease in the biological accessibility of the radionuclides. However, this trend depended on many factors. Plant and bottom feeding fish species were the first to reach the maximum contamination levels. No data are available on other vertebrates, but it can be assumed that the same trend was true for all plant feeding animals and animals searching for food on the soil surface. The most significant decrease of the average values occurred during the first 3-5 years after the accident and it was the most pronounced for elks and plant and plankton feeding fish. Their diet included elements “alienated” from the major radionuclide inventory; for example, upper soil layers and bottom deposits where the fallout that had originally precipitated on plants, water and soils gradually migrated. Further radionuclide penetration into deeper layers of soils and its bonding with their mineral components intensified decontamination of the fauna. It took a while for the contamination of predatory fish and mammals (wolves) to reach the maximum

  10. Gaseous polycyclic aromatic hydrocarbon concentrations are higher in urban forests than adjacent open areas during summer but not in winter--Exploratory study.

    Viippola, Viljami; Rantalainen, Anna-Lea; Yli-Pelkonen, Vesa; Tervo, Peatta; Setälä, Heikki

    2016-01-01

    While the potential of plants to uptake polycyclic aromatic hydrocarbons (PAHs) is widely acknowledged, empirical evidence of the effects of this process on local atmospheric PAH concentrations and human health is tenuous. We measured gaseous PAH concentrations using passive samplers in urban tree-covered areas and adjacent open, treeless areas in a near-road environment in Finland to gain information on the ability of urban vegetation to improve air quality. The ability of urban, mostly deciduous, vegetation to affect PAHs was season dependent: during summer, concentrations were significantly higher in tree-covered areas, while in the fall, concentrations in open areas exceeded those in tree-covered areas. During winter, concentrations in tree-covered areas were either lower or did not differ from those in open areas. Results of this study imply that the commonly believed notion that trees unequivocally improve air quality does not apply to PAHs studied here.

  11. Geodynamic settings of Mesozoic large-scale mineralization in North China and adjacent areas--Implication from the highly precise and accurate ages of metal deposits

    MAO; Jingwen; (毛景文); WANG; Yitian; (王义天); ZHANG; Zuoheng; (张作衡); YU; Jinjie; (余金杰); NIU; Baogui; (牛宝贵)

    2003-01-01

    Based on the summary of the highly precise datings of the metal deposits and related granitic rocks in North China craton and adjacent areas, such as the molybdenite Re-Os datings, 40Ar-39Ar datings of mica, K-feldspar and quartz, some Rb-Sr isochrons, and the SHRIMP zircon U-Pb dating and single grain zircon U-Pb dating, we suggest that the large-scale mineralization in North China craton and adjacent areas take place in three periods of 200-160Ma, 140Ma±, and 130-110Ma. Their corresponding geodynamic settings are proposed to be the collision orogenic process, transformation of the tectonic regime, and delamination of the lithosphere, respectively, in light of analyzing the Mesozoic geodynamic evolution in the North China craton.

  12. Adjacent segment disease.

    Virk, Sohrab S; Niedermeier, Steven; Yu, Elizabeth; Khan, Safdar N

    2014-08-01

    EDUCATIONAL OBJECTIVES As a result of reading this article, physicians should be able to: 1. Understand the forces that predispose adjacent cervical segments to degeneration. 2. Understand the challenges of radiographic evaluation in the diagnosis of cervical and lumbar adjacent segment disease. 3. Describe the changes in biomechanical forces applied to adjacent segments of lumbar vertebrae with fusion. 4. Know the risk factors for adjacent segment disease in spinal fusion. Adjacent segment disease (ASD) is a broad term encompassing many complications of spinal fusion, including listhesis, instability, herniated nucleus pulposus, stenosis, hypertrophic facet arthritis, scoliosis, and vertebral compression fracture. The area of the cervical spine where most fusions occur (C3-C7) is adjacent to a highly mobile upper cervical region, and this contributes to the biomechanical stress put on the adjacent cervical segments postfusion. Studies have shown that after fusion surgery, there is increased load on adjacent segments. Definitive treatment of ASD is a topic of continuing research, but in general, treatment choices are dictated by patient age and degree of debilitation. Investigators have also studied the risk factors associated with spinal fusion that may predispose certain patients to ASD postfusion, and these data are invaluable for properly counseling patients considering spinal fusion surgery. Biomechanical studies have confirmed the added stress on adjacent segments in the cervical and lumbar spine. The diagnosis of cervical ASD is complicated given the imprecise correlation of radiographic and clinical findings. Although radiological and clinical diagnoses do not always correlate, radiographs and clinical examination dictate how a patient with prolonged pain is treated. Options for both cervical and lumbar spine ASD include fusion and/or decompression. Current studies are encouraging regarding the adoption of arthroplasty in spinal surgery, but more long

  13. Soil thermal regime on ice-free areas in Livingston Island and James Ross Island, Antarctic Peninsula region

    Hrbáček, Filip; Oliva, Marc; Láska, Kamil; Ruiz-Fernández, Jesús; Ángel de Pablo, Miguel; Vieira, Gonçalo; Ramos, Miguel; Nývlt, Daniel

    2016-04-01

    Permafrost and active layer are considered prominent components of the Cryosphere, which react very sensitively to small climate variations. The Antarctic Peninsula (AP) region is considered as one of the fastest warming regions on Earth, where mean annual air temperature locally increased more than 2.5°C over the last 60 years. Significant climate differences are found between the eastern and western sides of the AP. While mean annual air temperatures (MAAT) oscillate around -1 to -2 °C and precipitation reach 800 mm w.e. year-1 in the western AP, the MAAT in the eastern AP are below -6 °C and precipitation does not exceed 500 mm. These differences determine different permafrost thickness and spatial distribution in these two regions, as well as diverse patterns of active layer dynamics. With the purpose to better understand the factors controlling the soil thermal regime in maritime permafrost environments, we examine data from 2014 acquired from several sites in Livingston Island (western AP) and James Ross Island (eastern AP). The study sites show similar characteristics in terms of topography (slope Ross Island ranged from -7.0 to -7.9 °C. Mean soil temperature at 5 cm depth was slightly higher than air temperature in both areas: -0.7 to -1.3 °C in Livingston Island and -6.2 to -6.3 °C in James Ross Island; the same occurred for soil temperature at 75 cm: -0.4 to -0.7 °C in Livingston Island and -6.0 to -6.6 °C James Ross Island. Significantly lower values of mean daily amplitude of soil temperature at 5 cm depth and the freezing n-factor values observed during the freezing season on Livingston Island suggest a pronounced insulating effect of snow cover in this area in comparison to James Ross Island. The mean daily amplitude of soil temperature at 5 cm ranged from 0.9 to 1.7 °C in Livingston Island, while it reached 3.0 to 4.0 °C in James Ross Island. The freezing n-factor reached 0.33 and 0.63 on Livingston Island, while 0.88 and 0.98 were

  14. Metazoan Parasites of Antarctic Fishes.

    Oğuz, Mehmet Cemal; Tepe, Yahya; Belk, Mark C; Heckmann, Richard A; Aslan, Burçak; Gürgen, Meryem; Bray, Rodney A; Akgül, Ülker

    2015-06-01

    To date, there have been nearly 100 papers published on metazoan parasites of Antarctic fishes, but there has not yet been any compilation of a species list of fish parasites for this large geographic area. Herein, we provide a list of all documented occurrences of monogenean, cestode, digenean, acanthocephalan, nematode, and hirudinean parasites of Antarctic fishes. The list includes nearly 250 parasite species found in 142 species of host fishes. It is likely that there are more species of fish parasites, which are yet to be documented from Antarctic waters.

  15. Biodiversity and biogeography of Antarctic and sub-Antarctic mollusca

    Linse, Katrin; Griffiths, Huw J.; Barnes, David K. A.; Clarke, Andrew

    2006-04-01

    For many decades molluscan data have been critical to the establishment of the concept of a global-scale increase in species richness from the poles to the equator. Low polar diversity is key to this latitudinal cline in diversity. Here we investigate richness patterns in the two largest classes of molluscs at both local and regional scales throughout the Southern Ocean. We show that biodiversity is very patchy in the Southern Ocean (at the 1000-km scale) and test the validity of historical biogeographic sub-regions and provinces. We used multivariate analysis of biodiversity patterns at species, genus and family levels to define richness hotspots within the Southern Ocean and transition areas. This process identified the following distinct sub-regions in the Southern Ocean: Antarctic Peninsula, Weddell Sea, East Antarctic—Dronning Maud Land, East Antarctic—Enderby Land, East Antarctic—Wilkes Land, Ross Sea, and the independent Scotia arc and sub Antarctic islands. Patterns of endemism were very different between the bivalves and gastropods. On the basis of distributional ranges and radiation centres of evolutionarily successful families and genera we define three biogeographic provinces in the Southern Ocean: (1) the continental high Antarctic province excluding the Antarctic Peninsula, (2) the Scotia Sea province including the Antarctic Peninsula, and (3) the sub Antarctic province comprising the islands in the vicinity of the Antarctic Circumpolar Current.

  16. Assessment of macroinvertebrate communities in adjacent urban stream basins, Kansas City, Missouri, metropolitan area, 2007 through 2011

    Christensen, Eric D.; Krempa, Heather M.

    2013-01-01

    Macroinvertebrates were collected as part of two separate urban water-quality studies from adjacent basins, the Blue River Basin (Kansas City, Missouri), the Little Blue River and Rock Creek Basins (Independence, Missouri), and their tributaries. Consistent collection and processing procedures between the studies allowed for statistical comparisons. Seven Blue River Basin sites, nine Little Blue River Basin sites, including Rock Creek, and two rural sites representative of Missouri ecological drainage units and the area’s ecoregions were used in the analysis. Different factors or levels of urban intensity may affect the basins and macroinvertebrate community metrics differently, even though both basins are substantially developed above their downstream streamgages (Blue River, 65 percent; Little Blue River, 52 percent). The Blue River has no flood control reservoirs and receives wastewater effluent and stormflow from a combined sewer system. The Little Blue River has flood control reservoirs, receives no wastewater effluent, and has a separate stormwater sewer system. Analysis of macroinvertebrate community structure with pollution-tolerance metrics and water-quality parameters indicated differences between the Blue River Basin and the Little Blue River Basin.

  17. Food web structure of the coastal area adjacent to the Tagus estuary revealed by stable isotope analysis

    Vinagre, C.; Máguas, C.; Cabral, H. N.; Costa, M. J.

    2012-01-01

    The identification of energy sources, pathways and trophic linkages among organisms is crucial for the understanding of food web dynamics. Stable isotopes were used to identify the trophic level of food web components and track the incorporation of organic matter of different origins in the coastal ecosystem adjacent to the Tagus estuary. It was shown that the river Tagus is a major source of organic carbon to this system. Also, the wide difference in δ 13C among the primary consumers allowed the identification of the pelagic and the benthic energy pathways. The maximum trophic level observed was 2.4 for Sepia officinalis. This value is indicative of a short food web. It was concluded that the diet of the upper trophic level species relies directly on the lower food web levels to a considerable extent, instead of relying mostly on intermediate trophic level species. Moreover, the δ 15N values of primary consumers were very close to that of particulate organic matter, probably due to poorly known processes occurring at the basis of the food web. This lowers the trophic length of the whole food web. Reliance on benthic affinity prey was high for all upper trophic level secondary consumers.

  18. Water Resources of the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah - Draft Report

    Welch, Alan H.; Bright, Daniel J.

    2007-01-01

    Summary of Major Findings This report summarizes results of a water-resources study for White Pine County, Nevada, and adjacent areas in east-central Nevada and western Utah. The Basin and Range carbonate-rock aquifer system (BARCAS) study was initiated in December 2004 through Federal legislation (Section 131 of the Lincoln County Conservation, Recreation, and Development Act of 2004) directing the Secretary of the Interior to complete a water-resources study through the U.S. Geological Survey, Desert Research Institute, and State of Utah. The study was designed as a regional water-resource assessment, with particular emphasis on summarizing the hydrogeologic framework and hydrologic processes that influence ground-water resources. The study area includes 13 hydrographic areas that cover most of White Pine County; in this report however, results for the northern and central parts of Little Smoky Valley were combined and presented as one hydrographic area. Hydrographic areas are the basic geographic units used by the State of Nevada and Utah and local agencies for water-resource planning and management, and are commonly defined on the basis of surface-water drainage areas. Hydrographic areas were further divided into subbasins that are separated by areas where bedrock is at or near the land surface. Subbasins represent subdivisions used in this study for estimating recharge, discharge, and water budget. Hydrographic areas represent the subdivision used for reporting summed and tabulated subbasin estimates.

  19. Water Resources of the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah

    Welch, Alan H.; Bright, Daniel J.; Knochenmus, Lari A.

    2008-01-01

    INTRODUCTION This report summarizes results of a water-resources study for White Pine County, Nevada, and adjacent areas in east-central Nevada and western Utah. The Basin and Range carbonate-rock aquifer system (BARCAS) study was initiated in December 2004 through Federal legislation (Section 301(e) of the Lincoln County Conservation, Recreation, and Development Act of 2004; PL108-424) directing the Secretary of the Interior to complete a water-resources study through the U.S. Geological Survey, Desert Research Institute, and State of Utah. The study was designed as a regional water-resource assessment, with particular emphasis on summarizing the hydrogeologic framework and hydrologic processes that influence ground-water resources. The study area includes 13 hydrographic areas that cover most of White Pine County; in this report however, results for the northern and central parts of Little Smoky Valley were combined and presented as one hydrographic area. Hydrographic areas are the basic geographic units used by the State of Nevada and Utah and local agencies for water-resource planning and management, and are commonly defined on the basis of surface-water drainage areas. Hydrographic areas were further divided into subbasins that are separated by areas where bedrock is at or near the land surface. Subbasins are the subdivisions used in this study for estimating recharge, discharge, and water budget. Hydrographic areas are the subdivision used for reporting summed and tabulated subbasin estimates.

  20. Literature and data review for the surface-water pathway: Columbia River and adjacent coastal areas. Hanford Environmental Dose Reconstruction Project

    Walters, W.H.; Dirkes, R.L.; Napier, B.A.

    1992-11-01

    As part of the Hanford Environmental Dose Reconstruction (HEDR) Project, Battelle, Pacific Northwest Laboratories reviewed literature and data on radionuclide concentrations and distribution in the water, sediment, and biota of the Columbia River and adjacent coastal areas. Over 600 documents were reviewed including Hanford reports, reports by offsite agencies, journal articles, and graduate theses. Radionuclide concentration data were used in preliminary estimates of individual dose for the period 1964 through 1966. This report summarizes the literature and database reviews and the results of the preliminary dose estimates.

  1. Literature and data review for the surface-water pathway: Columbia River and adjacent coastal areas. Hanford Environmental Dose Reconstruction Project

    Walters, W.H.; Dirkes, R.L.; Napier, B.A.

    1992-04-01

    As part of the Hanford Environmental Dose Reconstruction Project, Pacific Northwest Laboratory reviewed literature and data on radionuclide concentrations and distribution in the water, sediment, and biota of the Columbia River and adjacent coastal areas. Over 600 documents were reviewed including Hanford reports, reports by offsite agencies, journal articles, and graduate theses. Certain radionuclide concentration data were used in preliminary estimates of individual dose for the 1964--1966 time period. This report summarizes the literature and database review and the results of the preliminary dose estimates.

  2. Groundwater quality in the shallow aquifers of the Tulare, Kaweah, and Tule Groundwater Basins and adjacent highlands areas, Southern San Joaquin Valley, California

    Fram, Miranda S.

    2017-01-18

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The shallow aquifers of the Tulare, Kaweah, and Tule groundwater basins and adjacent highlands areas of the southern San Joaquin Valley constitute one of the study units being evaluated.

  3. Ice-Core Study of the Link between Sea-Salt Aerosol, Sea-Ice Cover and Climate in the Antarctic Peninsula Area

    Aristarain, A.J. [Laboratorio de Estratigrafia Glaciar y Geoquimica del Agua y de la Nieve LEGAN, Instituto Antartico Argentino, Mendoza (Argentina); Delmas, R.J. [Laboratoire de Glaciologie et Geophysique de l' Environnement LGGE, Centre National de la Recherche Scientifique, BP 96, 38402 St. Martin d' Heres Cedex (France); Stievenard, M. [Laboratoire des Sciences du Climat et de l' Environnement LSCE, Centre d' Etudes de Saclay, 91191 Gif-sur-Yvette, Cedex (France)

    2004-11-01

    Three ice cores and a set of snow pit samples collected on James Ross Island, Antarctic Peninsula, in 1979, 1981 and 1991 have been analyzed for water stable isotope content D or 18O (isotopic temperature) and major chemical species. A reliable and detailed chronological scale has been established first for the upper 24.5 m of water equivalent (1990-1943) where various data sets can be compared, then extended down to 59.5 m of water equivalent (1847) with the aid of seasonal variations and the sulphate peak reflecting the 1883 Krakatoa volcanic eruption. At James Ross Island, sea-salt aerosol is generally produced by ice-free marine surfaces during the summer months, although some winter sea-salt events have been observed. For the upper part of the core (1990-1943), correlations (positive or negative) were calculated between isotopic temperature, chloride content (a sea-salt indicator), sea-ice extent, regional atmospheric temperature changes and atmospheric circulation. The D and chloride content correlation was then extended back to 1847, making it possible to estimate decadal sea-ice cover fluctuations over the study period. Our findings suggest that ice-core records from James Ross Island reflect the recent warming and sea-ice decrease trends observed in the Antarctic Peninsula area from the mid-1940s.

  4. The importance of sea-ice area biases in 21st century multi-model projections of Antarctic net precipitation and temperature and their relative change

    Bracegirdle, T.

    2015-12-01

    Climate models exhibit large biases in sea ice area (SIA) in their historical simulations. This study has explored the impacts of these biases on multi-model uncertainty in CMIP5 ensemble projections of 21st century change in Antarctic surface temperature, net precipitation and SIA. The analysis is based on time slice climatologies in the RCP8.5 future scenario (2070-2099) and historical (1970-1999) simulations across 37 different CMIP5 models. Projected changes in net precipitation, temperature and SIA are found to be strongly associated with simulated historical mean SIA (e.g. cross-model correlations of r = 0.77, 0.70 and -0.86, respectively). Furthermore, historical SIA bias is found to have a large impact on the simulated ratio between net precipitation response and temperature response. This ratio is smaller in models with smaller-than-observed historical SIA. These findings are particularly relevant to quantifying and reducing model uncertainty in projections of Antarctic surface mass balance and associated contributions to sea level change.

  5. Interpretation of remote sensing of geological structures and prediction of gold mineralization in Mohe area and its adjacent region

    2007-01-01

    The authors took the ETM+ multi-spectra data as the data information and correlation coefficient for each band and carried out their information volume statistics. According to certain criteria, the authors also determined the optimum band-combined image. The image clarity is improved by various enhancements and fusions method. Based on remote sensing geological interpretation in detail, the relationship between remote sensing geological characters and gold mine were analyzed systemically. Using all kinds of remote sensing structure information, combining other research data, the authors determined mainly ore-controlling ore structure. Several prospective areas of gold ores were determined and furthermore significant finding mine target areas was confirmed.

  6. 33 CFR 165.501 - Chesapeake Bay entrance and Hampton Roads, VA and adjacent waters-Regulated Navigation Area.

    2010-07-01

    ... release), that is underway within two nautical miles of the CBBT or the I-664 Bridge Tunnel shall station... Port. (6) Requirements for navigation charts, radars, and pilots. No vessel over 100 gross tons may enter the Regulated Navigation Area, unless it has on board: (i) Corrected charts of the...

  7. Prediction and prevention of the impacts of sea level rise on the Yangtze River Delta and its adjacent areas

    施雅风; 朱季文; 谢志仁; 季子修; 蒋自巽; 杨桂山

    2000-01-01

    The Yangtze River Delta region is characterized by high density of population and rapidly developing economy. There are low lying coastal plain and deltaic plain in this region. Thus, the study area could be highly vulnerable to accelerated sea level rise caused by global warming. This paper deals with the scenarios of the relative sea level rise in the early half period of the 21st century in the study area. The authors suggested that relative sea level would rise 25-50 cm by the year 2050 in the study area, of which the magnitude of relative sea level rise in the Yangtze River Delta would double the perspective worldwide average. The impacts of sea level rise include: (i) exacerbation of coastline recession in several sections and vertical erosion of tidal flat, and increase in length of eroding coastline; (ii) decrease in area of tidal flat and coastal wetland due to erosion and inundation; (iii) increase in frequency and intensity of storm surge, which would threaten the coastal protection works; (i

  8. Preliminary study of the uranium favorability of the Jornada Del Muerto Basin and adjacent areas, South Central New Mexico

    Templain, C.J.; Dotterrer, F.E.

    1978-06-01

    Data indicate that possible uranium host rocks include the Precambrian rocks, the Ordovician Bat Cave Formation and Cable Canyon Sandstone, the Permian Abo Formation, Lower Cretaceous Dakota Sandstone, and the Upper Cretaceous-lower Tertiary McRae Formation. The Cenozoic sequence contains possible host beds; little is known, however, about its stratigraphy. Secondary uranium mineralization is found associated with faults in the Jornada area. All fault zones there are possible sites for uranium deposition. Possible sources for uranium in the Jornada del Muerto area include uraniferous Precambrian rocks, tuffaceous beds in the McRae Formation, and the Tertiary Datil and Thurman Formations. Hydrothermal solutions may have deposited the veinlike fluorite deposits, of which the purple varieties were found to be radioactive during this study.

  9. Vegetation Evaluation and Recommendations: Dredge Material Placement Areas and Adjacent Lands, Kaskaskia River Navigation Project, New Athens to Fayetteville.

    1981-06-03

    288 pp. Mohlenbrock, R. H. 1972. The illustrated flora of Illinois: Grasses : Bromus to Paspalum . Southern Illinois University Press, Carbondale...in less satur- ated areas are Desmodium paniculatum (panicled tick trefoil), Geum canadense (white avens), Paspalum fluitans (swamp bead grass ...tall fescue), Bromus inermis (smooth brome), and Tridens flavus (purple-top) are the most abundant and important grasses in the old fields. Major

  10. Prediction and prevention of the impacts of sea level rise on the Yangtze River Delta and its adjacent areas

    2000-01-01

    The Yangtze River Delta region is characterized by high density of population and rapidly developing economy. There are low lying coastal plain and deltaic plain in this region. Thus, the study area could be highly vulnerable to accelerated sea level rise caused by global warming. This paper deals with the scenarios of the relative sea level rise in the early half period of the 21st century in the study area. The authors suggested that relative sea level would rise 25 50 cm by the year 2050 in the study area, of which the magnitude of relative sea level rise in the Yangtze River Delta would double the perspective worldwide average. The impacts of sea level rise include: (i) exacerbation of coastline recession in several sections and vertical erosion of tidal flat, and increase in length of eroding coastline; (ii) decrease in area of tidal flat and coastal wetland due to erosion and inundation; (iii) increase in frequency and intensity of storm surge, which would threaten the coastal protection works; (iv) reduction of drainage capacity due to backwater effect in the Lixiahe lowland and the eastern lowland of Taihu Lake region, and exacerbation of flood and waterlogging disasters; and (v) increase in salt water intrusion into the Yangtze Estuary. Comprehensive evaluation of sea level rise impacts shows that the Yangtze River Delta and eastern lowland of Taihu Lake region, especially Shanghai Municipality, belong in the district in the extreme risk category and the next is the northern bank of Hangzhou Bay, the third is the abandoned Yellow River delta, and the district at low risk includes the central part of north Jiangsu coastal plain and Lixiahe lowland.

  11. Preliminary study on the dissolved oxygen distributions and the influential factors in the Daliao River estuary and its adjacent areas

    LEI Kun; MENG Wei; ZHENG Binghui; FU Guo

    2004-01-01

    Dissolved oxygen (DO) concentrations were surveyed in the Daliao River Estuary in autumn to investigate the temporaland spatial trends of DO distributions. The results indicate that DO is weakly stratified in the Yingkou section of theDaliao River Estuary, and remains constant vertically in the areas near and out of the entrance. Horizontally, both in-stantaneous and continuous observations show that the Yingkou section of the Daliao River Estuary is affected by hy-poxic conditions; while no conditions of low DO have been observed in the areas near and out of the entrance.DO-salinity correlations exhibit different controlling factors of DO distributions in different sections of the Daliao Riv-er Estuary. At the upstream part of the Yingkou section of the Daliao River (A1-A4), oxygen demanding materials and the associated biochemical processes are the main factor controlling the DO distribution, but in the lower part of theYingkou section and the area near and out of the entrance (A5-A15), tidal advections are more influential for DO distributions.

  12. Sequence-Stratigraphic Framework from the Carboniferous to the Permian Chuanshanian Epoch in Dianqiangui Basin and Its Adjacent Areas, Southwest China

    Mei Mingxiang; Ma Yongsheng; Deng Jun; Meng Qingfen; Li Donghai

    2005-01-01

    The Carboniferous can be divided into four series in the Dianqiangui basin and its adjacent areas, Southwest China: the Yanguanian series, the Datangian series, the Weiningian series and the Mapingian series. The Maping Formation, traditionally used as the lithostratigraphic unit of the Upper Carboniferous, became an inter-system unit from the Carboniferous to the Permian. Thus, the top part of the Carboniferous and the bottom part of the Permian (Chuanshanian series) constitute a third-order sequence in the Dianqiangui basin and its adjacent areas. In the study area, the Carboniferous system and the Chuanshanian series of the Permian constitute a second-order sequence that can be subdivided into 6 third-order sequences. The bottom boundary of this second-order sequence is an unconformity formed in the principal episode of the Ziyun movement (the second episode), and the top boundary is also an unconformity formed in the principal episode of the Qiangui movement (the second episode). In different paleogeographical backgrounds, the strata from the Carboniferous to the Permian Chuanshanian epoch are marked by different sedimentary features. For example, coal measures and more dolomitic strata are developed in the attached platform; carbonate rocks mainly constitute the isolated platform strata; the inter-platform ditch strata are mainly composed of dark and fine sediments. Therefore, third-order sequences with different architectures of sedimentary-facies succession are formed in different paleogeographical backgrounds. Although the third-order sequences are different in the architecture of sedimentary-succession in space, the processes of their depositional environmental changes due to the third-order relative sea-level changes are simultaneous. Biostratigraphically, the surfaces of the third-order sequences can be correlated and traced in space; the framework of sequence stratigraphy from the Carboniferous to the Chuanshanian epoch of the Permian can be established

  13. Surveys of mammal populations in the areas adjacent to Forsmark and Tierp. A pilot study 2001-2002

    Cederlund, Goeran; Hammarstroem, Angelica; Wallin, Kjell [Svensk Viltfoervaltning AB, Ramsberg (Sweden)

    2003-04-01

    The Swedish Nuclear Fuel and Waste Management Co is in the process of selecting a safe and environmentally acceptable location for the deep-level repository of radioactive waste. SKB has expressed the importance of monitoring mammal species that are of interest both in biodiversity issues and for local hunting and recreational purposes. To get relevant data on the dynamics of the mammal populations it is important to estimate the abundance and variations over time. Data achieved can be used to specifically monitor endangered species (like wolf, Canis lupus, and otter, Lutra lutra), detect effects from e.g. drilling activities on populations (important to hunters) and be used for assessment programs (MKB). One of the major goals is to monitor populations over several years and to obtain information that is essential for modelling of energy/carbon flows in the biosphere and ultimately calculations of the risks of exposure to radionuclide. From late 2001 to late spring 2002 a pilot study was accomplished in the areas surrounding the suggested areas in the Tierp region and in Forsmark (Oskarshamn was not included in this pilot study). A reference area was chosen near the coast some 20 km north of Forsmark. The aim was to initiate surveys of most of the larger mammal species that were expected to be found in the region. Selected species were wolf, lynx, otter, marten, mink, red fox, beaver, wild boar, red deer, roe deer, moose, European hare and mountain hare. Several methods were used and adapted to expected habitat use and expected local density of the species. Line transects were used on snow to index (frequency of tracks crossing the transects) or calculate actual number (for example the Buffon method). Pellet counts were used in spring to calculate hare and cervid (moose and deer species) density. In mid winter an aerial (helicopter) survey was conducted along the coast to count moose. The aquatic mammals were tracked on snow along selected parts of the streams and

  14. Present and Reference Concentrations and Yields of Suspended Sediment in Streams in the Great Lakes Region and Adjacent Areas

    Robertson, Dale M.; Saad, David A.; Heisey, Dennis M.

    2006-01-01

    In-stream suspended sediment and siltation and downstream sedimentation are common problems in surface waters throughout the United States. The most effective way to improve surface waters impaired by sediments is to reduce the contributions from human activities rather than try to reduce loadings from natural sources. Total suspended sediment/solids (TSS) concentration data were obtained from 964 streams in the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River Basins from 1951 to 2002. These data were used to estimate median concentrations, loads, yields, and volumetrically (flow) weighted (VW) concentrations where streamflow data were available. SPAtial Regression-Tree Analysis (SPARTA) was applied to land-use-adjusted (residualized) TSS data and environmental-characteristic data to determine the natural factors that best described the distribution of median and VW TSS concentrations and yields and to delineate zones with similar natural factors affecting TSS, enabling reference or natural concentrations and yields to be estimated. Soil properties (clay and organic-matter content, erodibility, and permeability), basin slope, and land use (percentage of agriculture) were the factors most strongly related to the distribution of median and VW TSS concentrations. TSS yields were most strongly related to amount of precipitation and the resulting runoff, and secondarily to the factors related to high TSS concentrations. Reference median TSS concentrations ranged from 5 to 26 milligrams per liter (mg/L), reference median annual VW TSS concentrations ranged from 10 to 168 mg/L, and reference TSS yields ranged from about 980 to 90,000 kilograms per square kilometer per year. Independent streams (streams with no overlapping drainage areas) with TSS data were ranked by how much their water quality exceeded reference concentrations and yields. Most streams exceeding reference conditions were in the central part of the study area, where agricultural activities

  15. Sequence Stratigraphic Delineation and Correlation of the Dongying Formation in the Nearshore and Adjacent Sea Areas, Bohai Bay Basin

    Zhu Hongtao; Du Yuansheng; Liu Keyu; Yan Jiaxin; Xu Yajun; Yang Ping; Liu Xinyu

    2008-01-01

    Based on the analysis of well logs, seismic data, core studies, the Dongying (东营) into three third-order sequences from base to top: namely, sequences SQ1, SQ2 and SQ3. The three sequences have different wireline (SP) log responses, showing triple-section characteristics with SQ1 being characterized by primarily flat baseline with intercalation of relatively low spontaneous potential, SQ2 generally exhibiting weak or moderate amplitude spontaneous potential with finger-shaped peaks, and SQ3 having relatively high spontaneous potential with funnel-shaped log curves. On the basis of the triple-section characteristics, the stratigraphic sequences can be correlated consistently throughout the entire study area. A stratigraphic and sedimentary model for sequences SQ1 to SQ3 of the Dongying Formation in the study area has been proposed. The accommodation space change in the two sides of the asymmetrical basin was examined and the asymmetrical basin has the feature of the asymmetrical accommodation space change. The asymmetrical physiography is a vital factor to influence the accommodation changes in additional to the lake level change, tectonism and sediment supply. This may have important implications to similar basins in other parts of China or elsewhere.

  16. 78 FR 48201 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    2013-08-07

    ... sites at various sub-Antarctic (within geographic coverage area of the Antarctic Treaty) and Antarctic... Antarctic Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541....

  17. Deep Background of Wenchuan Earthquake and the Upper Crust Structure beneath the Longmen Shan and Adjacent Areas

    LI Qiusheng; GAO Rui; WANG Haiyan; ZHANG Jisheng; LU Zhanwu; LI Pengwu; GUAN Ye; HE Rizheng

    2009-01-01

    By analyzing the deep seismic sounding profiles across the Longmen Shan, this paper focuses on the study of the relationship between the upper crust structure of the Longmen Shan area and the Wenchuan earthquake. The Longmen Shan thrust belt marks not only the topographical change, but also the lateral velocity variation between the eastern Tibetan Plateau and the Sichuan Basin. A low-velocity layer has consistently been found in the crust beneath the eastern edge of the Tibetan Plateau, and ends beneath the western Sichuan Basin. The low-velocity layer at a depth of -20 km beneath the eastern edge of the Tibetan Plateau has been considered as the deep condition for favoring energy accumulation that formed the great Wenchuan earthquake.

  18. Eco-environmental Change Records of Antarctic Ice-free Areas in the Sediments Influenced by Marine Animals%南极无冰区生态与环境变化在粪土层中的记录

    孙立广; 刘晓东

    2007-01-01

    The accumulative profiles of seabird and sea animal excrement together with the depositional sequences influenced by the excrement have been utilized to reconstruct the historical populations of Antarctic penguins and seals, also to study the eco-geology in the ice-free areas of Antarctica and Arctic. The historical populations of Antarctic penguins show dramatic fluctuations, the period of sharp decrease coincides well with Neoglaciation, and extremely cold or warm climate conditions are unfavorable for the survival of Antarctic penguin. The historical change of seal population seems to be related to climatic variations, sea-ice coverage and its forage behavior. The fluctuations of Hg (mercury) in the seal hairs and the sediments influenced by seal excrement were found to be closely associated with ancient gold and silver mining activities and the ancient civilization over the past several thousand years.

  19. Histochemical studies on intestinal metaplasia adjacent to gastric cardia adenocarcinoma in subjects at high-incidence area in Henan, north China

    She-Gan Gao; Hua-Qin Guo; Jun-Kuan Wang; Xiao-Shan Feng; Bao-Gen Ma; Li-Dong Wang; Zong-Min Fan; Ji-Lin Li; Xin He; Rui-Feng Guo; Dong-Ling Xie; Xin-Wei He; Shan-Shan Gao

    2005-01-01

    AIM: To characterize the histochemical type and pattern of intestinal metaplasia (IM) adjacent to gastric cardia adenocarcinoma (GCA) and distal gastric cancer (GC) in Linzhou, Henan Province, China.METHODS: Alcian-blue-periodic acid Schiff and high iron diamine-Alcian blue histochemical methods were performed on 142 cases of IM, including 49 cases of GCA and 93 cases of GC. All the patients were from Linzhou, Henan Province, China, the highest incidence area for both GCA and squamous cell carcinoma. Radio- or chemotherapy was not applied to these patients before surgery.RESULTS: The detection rate of IM in tissues adjacent to GCA tissues was 44.9%, which was significantly lower than that in GC tissues (80.64%, P<0.01). The rates of both incomplete small intestinal and colonic IM types identified by histochemistry in GCA tissues (31.82% and 63.64%, respectively) were significantly higher than those in GC (5.33% and 21.33%, respectively, P<0.01).CONCLUSION: IM in GCA and GC should be considered as a separate entity. Further research is needed to evaluate whether neoplastic progression of IM is related to its mucin profile in GCA.

  20. Adjacent Band Interference from San Diego Area Transmitters to Goldstone Deep Space Network Receivers Near 2300 Megahertz

    Ho, C.; Bathker, D.; Sue, M.; Peng, T.

    2001-10-01

    The Federal Communications Commission (FCC) has recently granted a commercial company a license to potentially deploy its wireless Internet system in the San Diego area in the 2300- to 2305-MHz frequency range. Each of several base station emitters would transmit a relatively strong effective isotropic radiated power (EIRP) (about 50 W). The frequency band is immediately above the band (2290 to 2300 MHz) used by NASA Deep Space Network (DSN) receiving stations at Goldstone, California. A potential interference problem to DSN receivers thus exists through some anomalous propagation modes, such as tropospheric ducting and rain scattering, and interference must be kept under a very small percentage of time (0.001 percent), as required by NASA deep-space missions. In this article, we have estimated the effects of interference from the wireless Internet system to Goldstone receivers. The calculation results show that at 2300 MHz the interference received by the DSN could exceed the DSN protection level up to 0.1 percent of the time for ducting propagation. For rain scattering, this could occur up to 2.3 percent of the time. At 2290 MHz, due to the transmitter spectrum, interference through either mode is below the DSN protection level. Interference through terrain diffraction will suffer very large attenuations at both frequencies. After considering that in the middle of the path there is a tall mountain peak that largely blocks the surface ducting and direct illumination of rain clouds, the interference generated by the wireless system emitters and propagated

  1. Tectonic evolution of the Songpan Garzê and adjacent areas (NE Tibet) from Triassic to Present : a synthesis.

    Roger, F.; Jolivet, M.; Malavieille, J.

    2009-04-01

    The 12th May 2008 Wenchuan earthquake in the Longmen Shan occurred on a large thrust fault largely inherited from an Indosinian structure itself probably controlled by an older structural heritage of the South China block continental margin. Within the whole northeast Tibet region, such a structural inheritance has had a major impact on the Tertiary deformation. It appears of primary importance to assess the pre-Tertiary tectonic evolution of the main blocks involved to understand the actual deformation in the eastern edge of Tibet. Over the past decades, the Proterozoic to Cenozoic tectonic, metamorphic and geochronologic history of the Longmen Shan and Songpan Garzê area have been largely studied. We present a synthesis of the tectonic evolution of the Songpan Garzê fold and thrust belt from Triassic to present. The Songpan-Garzê belt was formed during closure of a wide oceanic basin filled with a thick (5 to 15 km) sequence of Triassic flyschoid sediments [10]. Closure of the basin due to Triassic subduction involved strong shortening, intense folding and faulting of the Triassic series. A large-scale décollement, that presently outcrops along the eastern boundary of the belt (Danba area), allowed the growth of a wide and thick accretionary wedge [9]. It develops in the Paleozoic and Triassic series and separates the accretionary prism from an autochthonous crystalline basement [5, 12, 6] which shares many similarities with the basement of the Yangtze Craton (0.7-0.9 Ga). To the north and northwest, below the thickened Triassic series of the belt, the composition (oceanic or continental) of the basement remains unknown. During the Indosinian orogeny the emplacement of orogenic granites (220 - 150 Ma) was associated to crustal thickening [12, 13, 17, 15]. The isotopic composition of granitoids shows that their magma source were predominantly derived from melting of the proterozoic basement with varying degrees of sedimentary material and negligible mantle

  2. Antarctic crabs: invasion or endurance?

    Griffiths, Huw J; Whittle, Rowan J; Roberts, Stephen J; Belchier, Mark; Linse, Katrin

    2013-01-01

    Recent scientific interest following the "discovery" of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent warming trend continues, potentially decimating its native fauna. This "invasion hypothesis" suggests that decapod crabs were driven out of Antarctica 40-15 million years ago and are only now returning as "warm" enough habitats become available. The hypothesis is based on a geographically and spatially poor fossil record of a different group of crabs (Brachyura), and examination of relatively few Recent lithodid samples from the Antarctic slope. In this paper, we examine the existing lithodid fossil record and present the distribution and biogeographic patterns derived from over 16,000 records of Recent Southern Hemisphere crabs and lobsters. Globally, the lithodid fossil record consists of only two known specimens, neither of which comes from the Antarctic. Recent records show that 22 species of crabs and lobsters have been reported from the Southern Ocean, with 12 species found south of 60 °S. All are restricted to waters warmer than 0 °C, with their Antarctic distribution limited to the areas of seafloor dominated by Circumpolar Deep Water (CDW). Currently, CDW extends further and shallower onto the West Antarctic shelf than the known distribution ranges of most lithodid species examined. Geological evidence suggests that West Antarctic shelf could have been available for colonisation during the last 9,000 years. Distribution patterns, species richness, and levels of endemism all suggest that, rather than becoming extinct and recently re-invading from outside Antarctica, the lithodid crabs have likely persisted, and even radiated, on or near to Antarctic slope. We conclude there is no evidence for a modern-day "crab invasion". We recommend a repeated targeted lithodid sampling program along the West Antarctic shelf to fully test the validity of the "invasion hypothesis".

  3. Antarctic science preserve polluted

    Simarski, Lynn Teo

    Geophysicists are alarmed at the electromagnetic pollution of a research site in the Antarctic specifically set aside to study the ionosphere and magnetosphere. A private New Zealand communications company called Telecom recently constructed a satellite ground station within the boundaries of this Site of Special Scientific Interest (SSSI), protected since the mid-1970s. The placement of a commercial facility within this site sets an ominous precedent not only for the sanctity of other SSSIs, but also for Specially Protected Areas—preserves not even open to scientific research, such as certain penguin rookeries.The roughly rectangular, one-by-one-half mile site, located at Arrival Heights not far from McMurdo Station, is one of a number of areas protected under the Antarctic treaty for designated scientific activities. Many sites are set aside for geological or biological research, but this is the only one specifically for physical science.

  4. Geology, geochronology, and paleogeography of the southern Sonoma volcanic field and adjacent areas, northern San Francisco Bay region, California

    Wagner, D.L.; Saucedo, G.J.; Clahan, K.B.; Fleck, R.J.; Langenheim, V.E.; McLaughlin, R.J.; Sarna-Wojcicki, A. M.; Allen, J.R.; Deino, A.L.

    2011-01-01

    Recent geologic mapping in the northern San Francisco Bay region (California, USA) supported by radiometric dating and tephrochronologic correlations, provides insights into the framework geology, stratigraphy, tectonic evolution, and geologic history of this part of the San Andreas transform plate boundary. There are 25 new and existing radiometric dates that define three temporally distinct volcanic packages along the north margin of San Pablo Bay, i.e., the Burdell Mountain Volcanics (11.1 Ma), the Tolay Volcanics (ca. 10-8 Ma), and the Sonoma Volcanics (ca. 8-2.5 Ma). The Burdell Mountain and the Tolay Volcanics are allochthonous, having been displaced from the Quien Sabe Volcanics and the Berkeley Hills Volcanics, respectively. Two samples from a core of the Tolay Volcanics taken from the Murphy #1 well in the Petaluma oilfield yielded ages of 8.99 ?? 0.06 and 9.13 ?? 0.06 Ma, demonstrating that volcanic rocks exposed along Tolay Creek near Sears Point previously thought to be a separate unit, the Donnell Ranch volcanics, are part of the Tolay Volcanics. Other new dates reported herein show that volcanic rocks in the Meacham Hill area and extending southwest to the Burdell Mountain fault are also part of the Tolay Volcanics. In the Sonoma volcanic field, strongly bimodal volcanic sequences are intercalated with sediments. In the Mayacmas Mountains a belt of eruptive centers youngs to the north. The youngest of these volcanic centers at Sugarloaf Ridge, which lithologically, chemically, and temporally matches the Napa Valley eruptive center, was apparently displaced 30 km to the northwest by movement along the Carneros and West Napa faults. The older parts of the Sonoma Volcanics have been displaced at least 28 km along the RodgersCreek fault since ca. 7 Ma. The Petaluma Formation also youngs to the north along the Rodgers Creek-Hayward fault and the Bennett Valley fault. The Petaluma basin formed as part of the Contra Costa basin in the Late Miocene and was

  5. The Study on the Block Boundary's Driving Forces and Tectonic Stress Field of China Mainland and Its Adjacent Areas Using GPS Data

    Du Zhi-xing; Qu Ji-kun; Han Bao-min; Jin Feng-xiang; Chai Yan-ju

    2003-01-01

    After reviewing the inversion study on the driving forces of China mainland and its adjacent areas, the inversion computation is made by means of genetic finite element method and covering complex method based on the displacement observations of the Crustal Movement Observation Network of China. The whole procedures of inversion study, including parameter selection, computation conditions, inversion analysis and interpretation, are given out in details. Then some conclusions are drawn:(1)the main driving forces acting on China mainland are still from the collision of Indian plate with Eurasian plate;(2)the driving forces of Pacific plate and Philippine plate are significant to the eastern China;(3)the back basin of Japan sea arc is continuously extending;(4)the forces from north prevent the northern motion of China.

  6. Chloroplast DNA phylogeography reveals repeated range expansion in a widespread aquatic herb Hippuris vulgaris in the Qinghai-Tibetan Plateau and adjacent areas.

    Jin-Ming Chen

    Full Text Available BACKGROUND: The Qinghai-Tibetan Plateau (QTP is one of the most extensive habitats for alpine plants in the world. Climatic oscillations during the Quaternary ice age had a dramatic effect on species ranges on the QTP and the adjacent areas. However, how the distribution ranges of aquatic plant species shifted on the QTP in response to Quaternary climatic changes remains almost unknown. METHODOLOGY AND PRINCIPAL FINDINGS: We studied the phylogeography and demographic history of the widespread aquatic herb Hippuris vulgaris from the QTP and adjacent areas. Our sampling included 385 individuals from 47 natural populations of H. vulgaris. Using sequences from four chloroplast DNA (cpDNA non-coding regions, we distinguished eight different cpDNA haplotypes. From the cpDNA variation in H. vulgaris, we found a very high level of population differentiation (G ST = 0.819 but the phylogeographical structure remained obscure (N ST = 0.853>G ST = 0.819, P>0.05. Phylogenetic analyses revealed two main cpDNA haplotype lineages. The split between these two haplotype groups can be dated back to the mid-to-late Pleistocene (ca. 0.480 Myr. Mismatch distribution analyses showed that each of these had experienced a recent range expansion. These two expansions (ca. 0.12 and 0.17 Myr might have begun from the different refugees before the Last Glacial Maximum (LGM. CONCLUSIONS/SIGNIFICANCE: This study initiates a research on the phylogeography of aquatic herbs in the QTP and for the first time sheds light on the response of an alpine aquatic seed plant species in the QTP to Quaternary climate oscillations.

  7. Hydrographic Areas Within the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada and Adjacent Areas in Nevada and Utah

    U.S. Geological Survey, Department of the Interior — This data set consists of sub delineations of the hydrographic area (HA) boundaries and polygons drawn at 1:1,000,000 scale for the Great Basin supplemented by...

  8. Assessment of trace metals in droppings of Adélie penguins (Pygoscelis adeliae) from different locations of the Antarctic Peninsula area

    Jos E Celis; Winfred Espejo; Ricardo Barra; Daniel Gonzalez-Acua; Francisca Gonzalez; Solange Jara

    2015-01-01

    In recent decades, polar regions of the planet have witnessed an increase in human presence. Antarctica is considered one of the most pristine regions of the world, but it could be affected by pollution owing to anthropogenic activities, particularly in the Antarctic Peninsula. Human presence can increase the levels of some trace metals in Antarctic environments, an issue that needs to be evaluated. To acquire data of trace metal contamination in the Antarctic Peninsula region, concentrations (dry weight) of Cd, Pb, As, Cu, Hg and Zn in fresh excrement of Adélie penguins were determined by atomic absorption spectrophotometry. During the 2012/2013 austral summer, samples were collected from four important nesting sites on the Antarctic Peninsula:Arctowski Base, Kopaitic Island (both sites in the northern Antarctic Peninsula), Yalour Island and Avian Island (both sites in the southern Antarctic Peninsula). Data showed that Adélie penguin excreta had significantly higher levels (mg·kg-1) of As, Cd, Hg, Pb and Cu at Arctowski Base and Kopaitic Island, both sites that have major anthropogenic activities that probably contributed to increased metal levels. The levels of trace metals in Adélie penguins were similar to those reported in excreta of Antarctic species in previous studies, and lower than those in excreta of other Antarctic animals. Data suggest that metals ingested by these penguin species that feed in the sea, end up in terrestrial ecosystems.

  9. A GIS-based methodology to quantitatively define an Adjacent Protected Area in a shallow karst cavity: the case of Altamira cave.

    Elez, J; Cuezva, S; Fernandez-Cortes, A; Garcia-Anton, E; Benavente, D; Cañaveras, J C; Sanchez-Moral, S

    2013-03-30

    Different types of land use are usually present in the areas adjacent to many shallow karst cavities. Over time, the increasing amount of potentially harmful matter and energy, of mainly anthropic origin or influence, that reaches the interior of a shallow karst cavity can modify the hypogeal ecosystem and increase the risk of damage to the Palaeolithic rock art often preserved within the cavity. This study proposes a new Protected Area status based on the geological processes that control these matter and energy fluxes into the Altamira cave karst system. Analysis of the geological characteristics of the shallow karst system shows that direct and lateral infiltration, internal water circulation, ventilation, gas exchange and transmission of vibrations are the processes that control these matter and energy fluxes into the cave. This study applies a comprehensive methodological approach based on Geographic Information Systems (GIS) to establish the area of influence of each transfer process. The stratigraphic and structural characteristics of the interior of the cave were determined using 3D Laser Scanning topography combined with classical field work, data gathering, cartography and a porosity-permeability analysis of host rock samples. As a result, it was possible to determine the hydrogeological behavior of the cave. In addition, by mapping and modeling the surface parameters it was possible to identify the main features restricting hydrological behavior and hence direct and lateral infiltration into the cave. These surface parameters included the shape of the drainage network and a geomorphological and structural characterization via digital terrain models. Geological and geomorphological maps and models integrated into the GIS environment defined the areas involved in gas exchange and ventilation processes. Likewise, areas that could potentially transmit vibrations directly into the cave were identified. This study shows that it is possible to define a

  10. Effects of brush management on the hydrologic budget and water quality in and adjacent to Honey Creek State Natural Area, Comal County, Texas, 2001--10

    Banta, J. Ryan; Slattery, Richard N.

    2012-01-01

    Woody vegetation, including ashe juniper (Juniperus ashei), has encroached on some areas in central Texas that were historically oak grassland savannah. Encroachment of woody vegetation is generally attributed to overgrazing and fire suppression. Removing the ashe juniper and allowing native grasses to reestablish in the area as a brush management conservation practice (hereinafter referred to as "brush management") might change the hydrology in the watershed. These hydrologic changes might include changes to surface-water runoff, evapotranspiration, or groundwater recharge. The U.S. Geological Survey (USGS), in cooperation with Federal, State, and local partners, examined the hydrologic effects of brush management in two adjacent watersheds in Comal County, Tex. Hydrologic data were collected in the watersheds for 3-4 years (pre-treatment) depending on the type of data, after which brush management occurred on one watershed (treatment watershed) and the other was left in its original condition (reference watershed). Hydrologic data were collected in the study area for another 6 years (post-treatment). These hydrologic data included rainfall, streamflow, evapotranspiration, and water quality. Groundwater recharge was not directly measured, but potential groundwater recharge was calculated by using a simplified mass balance approach. This fact sheet summarizes highlights of the study from the USGS Scientific Investigations Report on which it is based.

  11. Sequence-stratigraphic frameworks and their palaeogeographic patterns for the Permian Lopingian of the Dianqiangui Basin and its adjacent areas of Southwestern China

    MEI MingXiang; MA YongSheng; DENG Jun; CHU HanMin; ZHENG KuanBing

    2007-01-01

    The Permian Lopingian in the Dianqiangui Basin and its adjacent areas is marked by the coal measures of the Wuchiapingian and the carbonate strata of the Changhsingian stages. For the Lopingian of the Dianqiangui Basin and its adjacent areas, the diversity of sedimentary facies and the obviousness of facies change provide an advantaged condition on a study of sequence stratigraphy. Approximately,the Wuchiapingian stage constitutes a third-order sequence and the Changhsingian stage forms another. For the Wuchiapingian stage in the study area, coal-measures were developed on the attached platform and, in addition, a special coal-measure that is composed of both limestone beds and coal beds was also developed in the central part of some isolated platforms. Grain-bank grainstones and packstones were formed on the margin of the attached platform as well as in the windward part of isolated platforms. For the Changhsingian stage in the study area, open-platform limestones were formed on the attached platform, while sponge-reef limestones were developed both on the margin of the attached platform and on the isolated platforms. The Lopingian Series is a set of basin-facies muddy shales with interbeds of silicalites in the inter-platform basin, which appears a set of the large-thick coarse clastic strata of molasses covering direct the deep-water strata from the Devonian to the Permian Yangsingian in the Qinzhou-Fangcheng region in the southern part of the study area. All of these features indicate the complexity of temporal-spatial facies-changes. Sequence-stratigraphic frameworks could be established, which would illustrate two types of facies-changing surfaces and diachronisms in the stratigraphic records, based on the combination of both biostratigraphic and chronostratigraphic materials and the regularity reflected by temporal evolutionary succession of sediments as well as spatial distributional patterns of sedimentary facies. Ultimately, features of sedimentary

  12. Sequence-stratigraphic frameworks and their palaeogeographic patterns for the Permian Lopingian of the Dianqiangui Basin and its adjacent areas of Southwestern China

    2007-01-01

    The Permian Lopingian in the Dianqiangui Basin and its adjacent areas is marked by the coal measures of the Wuchiapingian and the carbonate strata of the Changhsingian stages. For the Lopingian of the Dianqiangui Basin and its adjacent areas,the diversity of sedimentary facies and the obviousness of facies change provide an advantaged condition on a study of sequence stratigraphy. Approximately,the Wuchiapingian stage constitutes a third-order sequence and the Changhsingian stage forms an-other. For the Wuchiapingian stage in the study area,coal-measures were developed on the attached platform and,in addition,a special coal-measure that is composed of both limestone beds and coal beds was also developed in the central part of some isolated platforms. Grain-bank grainstones and packstones were formed on the margin of the attached platform as well as in the windward part of iso-lated platforms. For the Changhsingian stage in the study area,open-platform limestones were formed on the attached platform,while sponge-reef limestones were developed both on the margin of the at-tached platform and on the isolated platforms. The Lopingian Series is a set of basin-facies muddy shales with interbeds of silicalites in the inter-platform basin,which appears a set of the large-thick coarse clastic strata of molasses covering direct the deep-water strata from the Devonian to the Per-mian Yangsingian in the Qinzhou-Fangcheng region in the southern part of the study area. All of these features indicate the complexity of temporal-spatial facies-changes. Sequence-stratigraphic frame-works could be established,which would illustrate two types of facies-changing surfaces and dia-chronisms in the stratigraphic records,based on the combination of both biostratigraphic and chronostratigraphic materials and the regularity reflected by temporal evolutionary succession of sediments as well as spatial distributional patterns of sedimentary facies. Ultimately,features of sedi

  13. Evaluating the Effectiveness of Conservation on Mangroves: A Remote Sensing-Based Comparison for Two Adjacent Protected Areas in Shenzhen and Hong Kong, China

    Mingming Jia

    2016-07-01

    Full Text Available Mangroves are ecologically important ecosystems and globally protected. The purpose of this study was to evaluate the effectiveness of mangrove conservation efforts in two adjacent protected areas in China that were under the management policies of the Ramsar Convention (Mai Po Marshes Nature Reserve (MPMNR, Hong Kong and China’s National Nature Reserve System (Futian Mangrove National Nature Reserve (FMNNR, Shenzhen. To achieve this goal, eleven Landsat images were chosen and classified, areal extent and landscape metrics were then calculated. The results showed that: from 1973–2015, the areal extent of mangroves in both reserves increased, but the net change for the MPMNR (281.43 hm2 was much higher than those of the FMNNR (101.97 hm2. In general, the area-weighted centroid of the mangroves in FMNNR moved seaward by approximately 120 m, whereas in the MPMNR, the centroid moved seaward even farther (410 m. Although both reserves saw increased integrality and connectivity of the mangrove patches, the patches in the MPMNR always had higher integrality than those in the FMNNR. We concluded that the mangroves in the MPMNR were more effectively protected than those in the FMNNR. This study may provide assistance to the formulation of generally accepted criteria for remote sensing-based evaluation of conservation effectiveness, and may facilitate the development of appropriate mangrove forest conservation and management strategies in other counties.

  14. Geology, hydrogeology, and potential of intrinsic bioremediation at the National Park Service Dockside II site and adjacent areas, Charleston, South Carolina, 1993-94

    Campbell, B.G.; Petkewich, M.D.; Landmeyer, J.E.; Chapelle, F.H.

    1996-01-01

    A long history of industrial and commercial use of the National Park Service property and adjacent properties located in downtown Charleston, South Carolina, has caused extensive contamination of the shallow subsurface soils and water-table aquifer. The National Park Service property is located adjacent to a former manufactured-gas plant site, which is the major source of the contamination. Contamination of this shallow water-table aquifer is of concern because shallow ground water discharges to the Cooper River and contains contaminants, which may affect adjacent wildlife or human populations. The geology of the National Park Service property above the Ashley Formation of the Cooper Group consists of two Quaternary lithostratigraphic marine units, the Wando Formation and Holocene deposits, overlain by artificial fill. The Wando Formation overlies the Ashley Formation, a sandy calcareous clay, and consists of soft, organic clay overlain by gray sand. The Holocene deposits are composed of clayey to silty sand and soft organic-rich clay. The artificial fill, which was placed at the site to create dry land where salt marsh existed previously, is composed of sand, silt, and various scrap materials. The shallow hydrogeology of the National Park Service property overlying the Ashley Formation can be subdivided into two sandy aquifers separated by a leaky, black, organic-rich clay. The unconfined upper surficial aquifer is primarily artificial fill. The lower surficial aquifer consists of the Wando sand unit and is confined by the leaky organic-rich clay. Aquifer tests performed on the wells screened in these aquifers resulted in hydraulic conductivities from 0.1 to 10 feet per day for the upper surficial aquifer, and 16 feet per day for the lower surficial aquifer. Vertical hydraulic gradients at the site are typically low. A downward gradient from the upper surficial aquifer to the lower surficial aquifer occurs throughout most of the year. A brick-lined storm

  15. Seasonal variations of dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) in the sea-surface microlayer and subsurface water of Jiaozhou Bay and its adjacent area

    ZHANG Honghai; YANG Guipeng; LIU Chunying; LI Chenxuan

    2009-01-01

    The distributions of DMS and its precursor dimethylsulfoniopropionate, in both dissolved (DMSPd)and particulate fractions (DMSPp) were determined in the sea-surface microlayer and corresponding subsurface water of the Jiaozhou Bay, China and its adjacent area in May and August 2006.The concentrations of all these components showed a clear seasonal variation, with higher concentrations occurring in summer. This can be mainly attributed to the higher phytoplankton biomass observed in summer. Simultaneously, the enrichment extents of DMSPd and DMSPp in the microlayer also exhibited seasonal changes, with higher values in spring and lower ones in summer.Higher water temperature and stronger radiant intensity in summer can enhance their solubilityand photochemical reaction in the microlayer water, reducing their enrichment factors (the ratio of concentration in the microlayer to that in the corresponding subsurface water). A statistically significant relationship was found between the microlayer and subsurface water concentrations of DMS, DMSP and chlorophyll a, demonstrating that the biogenic materials in the microlayer come primarily from the underlying water. Moreover, our data show that the concentrations of DMSPp and DMS were significantly correlated with the levels of chlorophyll a, indicating that phytoplankton biomass might play an important role in controlling the distributions of biogenic sulfurs in the study area. The ratios of DMS/chlorophyll a and DMSPp/chlorophyll a varied little from spring to summer, suggesting that there was no obvious change in the proportion of DMSP producers in the phytoplankton community. The mean sea-to-air flux of DMS from the study area was estimated to be 5.70μmol/(m2·d),which highlights the effects of human impacts on DMS emision.

  16. The Influence of Urbanism and Information Consumption on Political Dimensions of Social Capital: Exploratory Study of the Localities Adjacent to the Core City from Brasov Metropolitan Area, Romania.

    Cătălina-Ionela Rezeanu

    Full Text Available The last two decades have seen a growing trend towards the research of voting behavior in post-communist countries. Urban sociology theorists state that not only space structures influence political participation, but also space structures are changing under the influence of global, local, and individual factors. The growing role played by information in the globalised world has accelerated the paradigm shift in urban sociology: from central place model (based on urban-rural distinction and on monocentric metropolitan areas to network society (based on space of flows and polycentric metropolitan areas. However, recent studies have mainly focused on countries with solid democracies, rather than on former communist countries. The present study aims to analyze the extent to which a new emerging spatial structure can be envisaged within a metropolitan area of Romania and its consequences for the political dimensions of social capital.The Transilvania University Ethics Commission approved this study (S1 Aprouval. The research is based upon individual and aggregate empirical data, collected from the areas adjacent to the core city in Brașov metropolitan area. Individual data has been collected during October 2012, using the oral survey technique (S1 Survey, based on a standardized questionnaire (stratified simple random sample, N = 600. The National Institute of Statistics and the Electoral Register provided the aggregate data per locality. Unvaried and multivariate analyses (hierarchical regression method were conducted based on these data.Some dimensions of urbanism, identified as predictors of the political dimensions of social capital, suggest that the area under analysis has a predominantly monocentric character, where the rural-urban distinction continues to remain relevant. There are also arguments favoring the dissolution of the rural-urban distinction and the emergence of polycentric spatial structures. The presence of some influences

  17. Turbines and Terrestrial Vertebrates: Variation in Tortoise Survivorship Between a Wind Energy Facility and an Adjacent Undisturbed Wildland Area in the Desert Southwest (USA).

    Agha, Mickey; Lovich, Jeffrey E; Ennen, Joshua R; Augustine, Benjamin; Arundel, Terence R; Murphy, Mason O; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Delaney, David; Briggs, Jessica; Austin, Meaghan; Madrak, Sheila V; Price, Steven J

    2015-08-01

    With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises (Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18-year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability, and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility-scale wind energy on long-lived terrestrial vertebrates.

  18. Turbines and Terrestrial Vertebrates: Variation in Tortoise Survivorship Between a Wind Energy Facility and an Adjacent Undisturbed Wildland Area in the Desert Southwest (USA)

    Agha, Mickey; Lovich, Jeffrey E.; Ennen, Joshua R.; Augustine, Benjamin; Arundel, Terence R.; Murphy, Mason O.; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Delaney, David; Briggs, Jessica; Austin, Meaghan; Madrak, Sheila V.; Price, Steven J.

    2015-08-01

    With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises ( Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18-year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability, and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility-scale wind energy on long-lived terrestrial vertebrates.

  19. Assessment of the Threats to the Biodiversity and Habitats in "Stara Reka" Reserve (Bulgaria and Its Adjacent Subalpine and Alpine Areas

    Svetlana V. Yocheva

    2013-06-01

    Full Text Available The assessment of the threats in the “Stara Reka” reserve and its adjacent subalpine and alpine areas is important since it makes it possible the appropriate conservation measures to be taken in order to prevent or reduce the negative effects on the biodiversity and habitats. The assessment was based on systematic studies and visits in the “Stara Reka” Reserve, located within National Park “Central Balkan” (Bulgaria, during spring, summer and autumn seasons of 2010-2011. A number of threats were recorded, where those by anthropogenic origin were predominating. Tourists have negatively influenced the wild plants such as Allium ursinum, Inula helenium and Primula frondosa by picking them up. Damages were registered on the information system and signs. Waste disposal, fires, poaching and illegal fishing were also some of the recorded threats. Many natural succession changes quite dynamically vary the habitats in the reserve, but the most dangerous for the biodiversity and degradation of habitats remain fires, erosion and introduction of alien species.

  20. Natural Parasitism in Fruit Fly (Diptera: Tephritidae) Populations in Disturbed Areas Adjacent to Commercial Mango Orchards in Chiapas and Veracruz, Mexico.

    Montoya, Pablo; Ayala, Amanda; López, Patricia; Cancino, Jorge; Cabrera, Héctor; Cruz, Jassmin; Martinez, Ana Mabel; Figueroa, Isaac; Liedo, Pablo

    2016-04-01

    To determine the natural parasitism in fruit fly populations in disturbed areas adjacent to commercial mango orchards in the states of Chiapas and Veracruz, Mexico, we recorded over one year the fruit fly-host associations, fly infestation, and parasitism rates in backyard orchards and patches of native vegetation. We also investigated the relationship between fruit size, level of larval infestation, and percent of parasitism, and attempted to determine the presence of superparasitism. The most recurrent species in trap catches was Anastrepha obliqua (Macquart), followed by Anastrepha ludens (Loew), in both study zones. The fruit infestation rates were higher in Chiapas than in Veracruz, with A. obliqua again being the most conspicuous species emerging from collected fruits. The diversity of parasitoids species attacking fruit fly larvae was greater in Chiapas, with a predominance of Doryctobracon areolatus (Szépligeti) in both sites, although the exotic Diachasmimorpha longicaudata (Ashmead) was well established in Chiapas. Fruit size was positively correlated with the number of larvae per fruit, but this relationship was not observed in the level of parasitism. The number of oviposition scars was not related to the number of immature parasitoids inside the pupa of D. areolatus emerging from plum fruits. Mass releases of Di. longicaudata seem not to affect the presence or prevalence of the native species. Our findings open new research scenarios on the role and impact of native parasitoid species attacking Anastrepha flies that can contribute to the development of sound strategies for using these species in projects for augmentative biological control.

  1. Turbines and terrestrial vertebrates: variation in tortoise survivorship between a wind energy facility and an adjacent undisturbed wildland area in the desert southwest (USA)

    Agha, Mickey; Lovich, Jeffrey E.; Ennen, Joshua R.; Augustine, Benjamin J.; Arundel, Terry; Murphy, Mason O.; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Delaney, David F.; Briggs, Jessica; Austin, Meaghan; Madrak, Sheila V.; Price, Steven J.

    2015-01-01

    With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises (Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18 year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility scale wind energy on long-lived terrestrial vertebrates.

  2. [Spatial distribution and pollution assessment of heavy metals in the tidal reach and its adjacent sea estuary of Daliaohe area, China ].

    Zhang, Lei; Qin, Yan-wen; Ma, Ying-qun; Zhao, Yan-min; Shi, Yao

    2014-09-01

    The aim of this article was to explore the pollution level of heavy metals in the tidal reach and its adjacent sea estuary of Daliaohe area. The contents and spatial distribution of As, Cd, Cr, Cu, Ph and Zn in surface water, suspended solids and surface sediments were analyzed respectively. The integrated pollution index and geoaccumulation index were used to evaluate the contamination degree of heavy metals in surface water and surface sediments respectively. The results indicated that the contents of heavy metals in surface water was in the order of Pb sea. Compared with the contents of heavy metals in surface water of the typical domestic estuary in China, the overall contents of heavy metals in surface water were at a higher level. The contents of heavy metals in suspended solids was in the order of Cd pollution index assessment showed that the water quality was good except individual stations. The geoaccumulation index assessment showed that As was the major pollution element in surface sediments.

  3. An Analysis on Australian Submission for Delimitation in Outer Limits of Continental Shelves Related to Antarctic Area%澳大利亚南极外大陆架划界案评析

    吴宁铂

    2015-01-01

    2004年,澳大利亚在7个南极主权要求国中率先向联合国大陆架界限委员会提交进入南纬60°以南———《南极条约》适用区域的200海里外大陆架划界申请案。①在坚持“南极主权”的前提下,澳大利亚对南极领地外大陆架与亚南极岛屿外大陆架划界问题采取了高度灵活的区分政策,在维持其南极领土主张现状的同时,又通过对《南极条约》体系及《联合国海洋法公约》巧妙地解读与运用,确保了本国利益的最大化。不过,由此引发的相关国际法问题还有待进一步剖析和解决。%Australia has taken the lead to make the submission for the delimitation in outer limits of conti-nental shelves beyond 200 nautical miles which penetrate into the Antarctic Treaty area south of 60°S to the Commission on the Limits of the Continental Shelf ( CLCS) among seven Antarctic sovereignty claimants in 2004 .Australia has adopted highly flexible policies on the issue of delimiting the outer limits of continental shelves beyond 200 nautical miles between Australian Antarctic Territory and Sub-Antarctic islands on the premise of insisting in its “Antarctic sovereignty” .Australia not only maintains the status quo of its claim to Antarctic territorial sovereignty but also guarantees national interest maximization by tactful interpretation and utilization of the Antarctic Treaty System as well as United Nations Convention on the Law of the Sea (UNCLOS).However, the international legal issues caused by the submissions are needed to be analyzed and solved .

  4. Tectonic structure of Dokdo and adjacent area in the northeastern part of the Ulleung Basin of the East Sea using geophysical data

    Kim, C.; Jeong, E.; Park, C.; Kwon, B.; Park, G.; Park, J.

    2008-12-01

    The northeastern part of the Ulleung Basin in the East Sea is composed of volcanic islands (Ulleungdo and Dokdo), seamounts (the Anyongbok Seamount, the Simheungtaek and the Isabu Tablemounts), and a deep pathway (Korea Gap). To understand tectonic structure and geophysical characteristics of Dokdo and adjacent area, We analysed geophysical potential data of KORDI(Korea Ocean Research and Development Institute), KIGAM(Korea Institute of Geoscience and Mineral Resources), and NORI(National Oceanographic Research Institute of Korea) around the Dokdo volcanic body except Ulleung Do because of empty data of its large island. Also, we eliminate the effect of water and sediments from the free-air gravity data to process 3D Moho depth inversion. 3D tectonic structure modelling of the study area was developed using Moho depth inversion result and sediment thickness data of NGDC(National Geophysical Data Center). The free-air gravity anomalies of the study area generally reflect bathymetric effects. Although the Dokdo seamounts have a similar topographic size, the decrease of free-air anomaly toward Isabu suggest that Isabu is oldest among the seaounts and have high degree of isostatic compensation. High Bouguer anomalies in the central part of the Ulleung Basin gradually decreases toward the Oki Bank. This feature suggests that the crust/mantle boundary is shallow in the central part of the Ulleung Basin. The complex magnetic pattern of Dokdo suggests that it might have erupted several times during its formation. The magnetic anomaly amplitude of Isabu is much smaller than that of Dokdo. Such low magnetic anomalies are attributed to a secondary change caused by the metamorphism or weathering of ferromagnetic minerals of the seamount during a long period of time after its formation. Analytic signals show high anomalous zones over volcanoes. Also, there are high analytic signal values in Korea Gap indicating magmatic intrusion in thick sediments. The power spectrum analysis

  5. Nd isotopic variation of Paleozoic-Mesozoic granitoids from the Da Hinggan Mountains and adjacent areas, NE Asia: Implications for the architecture and growth of continental crust

    Yang, Qidi; Wang, Tao; Guo, Lei; Tong, Ying; Zhang, Lei; Zhang, Jianjun; Hou, Zengqian

    2017-02-01

    There is a long-standing controversy regarding the tectonic division, composition and structure of the continental crust in the Da Hinggan Mountains and adjacent areas, which are mainly part of the southeastern Central Asian Orogenic Belt (CAOB). This paper approaches these issues via neodymium isotopic mapping of Paleozoic-Mesozoic (480 to 100 Ma) granitoids. On the basis of 943 published and 8 new whole-rock Nd isotopic data, the study area can be divided into four Nd isotopic provinces (I, II, III and IV). Province I (the youngest crust, Nd model ages (TDM) = 0.8-0.2 Ga) is a remarkable region of Phanerozoic crustal growth, which may reflect a major zone for closures of the Paleo-Asian Ocean. Province II (slightly juvenile crust, TDM = 1.0-0.8 Ga), the largest Nd isotopic province in the southeastern CAOB, is considered to reflect the recycling of the initial crustal material produced during the early stage (Early Neoproterozoic) evolution of the Paleo-Asian Ocean. Province III (slightly old crust, TDM = 1.6-1.1 Ga) is characterized by ancient crustal blocks, such as the central Mongolian, Erguna, Dariganga and Hutag Uul-Xilinhot blocks, which represent micro-continents and Precambrian basements in the southeastern CAOB. Several parts of Province III are located along the northern margin of the North China Craton (NCC), which is interpreted as a destroyed cratonic margin during the Paleozoic and Mesozoic. Province IV (the oldest crust, TDM = 2.9-1.6 Ga) mainly occurs within the NCC and reflects its typical Precambrian nature. These mapping results indicate that the boundary between Provinces II and III (the northern margin of the NCC) along the Solonker-Xar Moron Fault can be regarded as the lithospheric boundary between the CAOB and NCC. Provinces I and II account for 20% and 44% of the area of the southeastern CAOB, respectively, and therefore the ratio of continental growth is 64% from the Neoproterozoic to the Mesozoic, which is typical for this part of the

  6. Effects of brush management on the hydrologic budget and water quality in and adjacent to Honey Creek State Natural Area, Comal County, Texas, 2001-10

    Banta, J. Ryan; Slattery, Richard N.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Natural Resources Conservation Service, the Edwards Region Grazing Lands Conservation Initiative, the Texas State Soil and Water Conservation Board, the San Antonio River Authority, the Edwards Aquifer Authority, Texas Parks and Wildlife, the Guadalupe Blanco River Authority, and the San Antonio Water System, evaluated the hydrologic effects of ashe juniper (Juniperus ashei) removal as a brush management conservation practice in and adjacent to the Honey Creek State Natural Area in Comal County, Tex. By removing the ashe juniper and allowing native grasses to reestablish in the area as a brush management conservation practice, the hydrology in the watershed might change. Using a simplified mass balance approach of the hydrologic cycle, the incoming rainfall was distributed to surface water runoff, evapotranspiration, or groundwater recharge. After hydrologic data were collected in adjacent watersheds for 3 years, brush management occurred on the treatment watershed while the reference watershed was left in its original condition. Hydrologic data were collected for another 6 years. Hydrologic data include rainfall, streamflow, evapotranspiration, and water quality. Groundwater recharge was not directly measured but potential groundwater recharge was calculated using a simplified mass balance approach. The resulting hydrologic datasets were examined for differences between the watersheds and between pre- and post-treatment periods to assess the effects of brush management. The streamflow to rainfall relation (expressed as event unit runoff to event rainfall relation) did not change between the watersheds during pre- and post-treatment periods. The daily evapotranspiration rates at the reference watershed and treatment watershed sites exhibited a seasonal cycle during the pre- and post-treatment periods, with intra- and interannual variability. Statistical analyses indicate the mean

  7. Carbon and nitrogen isotopes analysis and sources of organic matter in surface sediments from the Sanggou Bay and its adjacent areas, China

    XIA Bin; CUI Yi; CHEN Bijuan; CUI Zhengguo; QU Keming; MA Feifei

    2014-01-01

    Naturally existing stable carbon and nitrogen isotopes are important in the study of sedimentary organic matter sources. To identify the sources of sedimentary organic matter in Sanggou Bay and its adjacent areas, which is characterized by high-density shellfish and seaweed aquaculture, the grain size, organic carbon (OC), total nitrogen (TN), carbon and nitrogen isotopic composition (δ13C andδ15N) of organic matter in the surface sediment were determined. The results showed that, in August, sedimentary OC and TN ranged from 0.17% to 0.76% and 0.04% to 0.14%, respectively. In November, OC and TN ranged from 0.23% to 0.87% and 0.05% to 0.14%, respectively. There was a significant positive correlation between OC and TN (R=0.98, P<0.0001), indicating that OC and TN were homologous. In August, theδ13C andδ15N of organic matter varied from −23.06‰ to −21.59‰ and 5.10‰ to 6.31‰, respectively. In November,δ13C andδ15N ranged from −22.87‰ to −21.34‰ and 5.13‰ to 7.31‰, respectively. This study found that the major sources of sedimentary organic matter were marine shellfish biodeposition, seaweed farming, and soil organic matter. Using a three-end-member mixed model, we estimated that the dominant source of sedimentary organic matter was shellfish biodeposition, with an average contribution rate of 65.53% in August and 43.00% in November. Thus, shellfish farming had a significant influence on the coastal carbon cycle.

  8. Dependence of the cyclization of branched tetraethers (CBT) on soil moisture in the Chinese Loess Plateau and the adjacent areas: implications for palaeorainfall reconstructions

    Wang, H.; Liu, W.; Zhang, C. L.

    2014-06-01

    Branched glycerol dialkyl glycerol tetraethers (bGDGTs) have been show promising for continental paleotemperature studies in loess-paleosol sequences (LPSs). Thus far, however, little is known about the effect of soil moisture on their distributions on the Chinese Loess Plateau (CLP). In this study, the relationships between environmental variables and the cyclization of bGDGTs (the so called CBT index) were investigated in a comprehensive set of surface soils in the CLP and its adjacent arid/semi-arid areas. We find that CBT correlates best with soil water content (SWC) or mean annual precipitation (MAP) for the total sample set. Particularly for the CLP soils, there is a significant positive relationship between CBT and MAP (CBT = -0.0021 · MAP + 1.7, n = 37, R2 = 0.87; MAP range: 210-680 mm). This indicates that CBT is mainly controlled by soil moisture in the alkalescent soils (pH > 7) in arid/semi-arid regions, where it is not sensitive to soil pH. Therefore, we suggest that CBT can potentially be used as a palaeorainfall proxy on the CLP. According to the preliminary CBT-MAP relationship for modern CLP soils, palaeorainfall history was reconstructed from three LPSs (Yuanbao, Lantian, and Mangshan) with published bGDGT data spanning the past 70 ka. The CBT-derived MAP records of the three sites consistently show precession-driven variations resembling the speleothem δ18O monsoon record, and are also in general accord with the fluctuations of the respective magnetic susceptibility (MS) record, supporting CBT as a reasonable proxy for palaeorainfall reconstruction in LPS studies. Moreover, the comparison of CBT-derived MAP and bGDGT-derived temperature may enable us to further assess the relative timing and magnitude of hydrological and thermal changes on the CLP, independent of chronology.

  9. Seasonal characteristics of size-fractionated phytoplankton community and fate of photosynthesized carbon in a sub-Antarctic area (Straits of Magellan)

    Decembrini, Franco; Bergamasco, Alessandro; Mangoni, Olga

    2014-08-01

    Phytoplankton community size drives the rates of biogenic carbon and the overall structure and dynamics of the marine pelagic food web. The Straits of Magellan, an inland passage between the Pacific and Atlantic Oceans, can be separated into three main sub-basins: the western-Pacific, the V-shaped central zone, and the eastern-Atlantic. To provide insights into the food structure of the phytoplankton community, size-fractionated chlorophyll a concentration and primary production rates were measured across the three sectors of the Magellan Straits in four periods between 1989 and 1995 in the Straits. Phytoplanktonic biomass and production ratios provided ecological insights into the food web structure, including the relevance of grazing in its largest fraction. The micro-phytoplanktonic fraction (> 10 μm) in the Pacific sub-basin is significantly less abundant than in the Central and Atlantic ones. Conversely, the lowest abundance of the pico-fraction (partially spilling out into the Atlantic sector. The most active grazing activities occur in the Central sub-basin during the spring bloom and appear even stronger in summer. Our results pinpoint also that the basic levels of the planktonic food web rely on the nanophytoplankton (10-2 μm) fraction, which is the main contributor to the continuum multivorous food web. When external energy (e.g. nutrient pulses from land freshwater and water mixing) enters the system, the structure of the plankton in the Straits shifts towards the herbivorous food web and is characterized by the presence of large-size diatoms. This dynamics keeps the system in a persistent mesotrophic state, featuring a lower trophic status than the Antarctic ones but much higher than that of oligotrophic temperate areas.

  10. Groundwater and surface-water resources in the Bureau of Land Management Moab Master Leasing Plan area and adjacent areas, Grand and San Juan Counties, Utah, and Mesa and Montrose Counties, Colorado

    Masbruch, Melissa D.; Shope, Christopher L.

    2014-01-01

    The Bureau of Land Management (BLM) Canyon Country District Office is preparing a leasing plan known as the Moab Master Leasing Plan (Moab MLP) for oil, gas, and potash mineral rights in an area encompassing 946,469 acres in southeastern Utah. The BLM has identified water resources as being potentially affected by oil, gas, and potash development and has requested that the U.S. Geological Survey prepare a summary of existing water-resources information for the Moab MLP area. This report includes a summary and synthesis of previous and ongoing investigations conducted in the Moab MLP and adjacent areas in Utah and Colorado from the early 1930s through the late 2000s.Eight principal aquifers and six confining units were identified within the study area. Permeability is a function of both the primary permeability from interstitial pore connectivity and secondary permeability created by karst features or faults and fractures. Vertical hydraulic connection generally is restricted to strongly folded and fractured zones, which are concentrated along steeply dipping monoclines and in narrow regions encompassing igneous and salt intrusive masses. Several studies have identified both an upper and lower aquifer system separated by the Pennsylvanian age Paradox Member of the Hermosa Formation evaporite, which is considered a confining unit and is present throughout large parts of the study area.Surface-water resources of the study area are dominated by the Colorado River. Several perennial and ephemeral or intermittent tributaries join the Colorado River as it flows from northeast to southwest across the study area. An annual spring snowmelt and runoff event dominates the hydrology of streams draining mountainous parts of the study area, and most perennial streams in the study area are snowmelt-dominated. A bimodal distribution is observed in hydrographs from some sites with a late-spring snowmelt-runoff peak followed by smaller peaks of shorter duration during the late summer

  11. In situ cosmogenic radiocarbon production and 2-D ice flow line modeling for an Antarctic blue ice area

    Buizert, Christo; Petrenko, Vasilii V.; Kavanaugh, Jeffrey L.; Cuffey, Kurt M.; Lifton, Nathaniel A.; Brook, Edward J.; Severinghaus, Jeffrey P.

    2012-06-01

    Radiocarbon measurements at ice margin sites and blue ice areas can potentially be used for ice dating, ablation rate estimates and paleoclimatic reconstructions. Part of the measured signal comes from in situ cosmogenic 14C production in ice, and this component must be well understood before useful information can be extracted from 14C data. We combine cosmic ray scaling and production estimates with a two-dimensional ice flow line model to study cosmogenic 14C production at Taylor Glacier, Antarctica. We find (1) that 14C production through thermal neutron capture by nitrogen in air bubbles is negligible; (2) that including ice flow patterns caused by basal topography can lead to a surface 14C activity that differs by up to 25% from the activity calculated using an ablation-only approximation, which is used in all prior work; and (3) that at high ablation margin sites, solar modulation of the cosmic ray flux may change the strength of the dominant spallogenic production by up to 10%. As part of this effort we model two-dimensional ice flow along the central flow line of Taylor Glacier. We present two methods for parameterizing vertical strain rates, and assess which method is more reliable for Taylor Glacier. Finally, we present a sensitivity study from which we conclude that uncertainties in published cosmogenic production rates are the largest source of potential error. The results presented here can inform ongoing and future 14C and ice flow studies at ice margin sites, including important paleoclimatic applications such as the reconstruction of paleoatmospheric 14C content of methane.

  12. Geologic framework of pre-Cretaceous rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico

    Condon, Steven M.

    1992-01-01

    This report is a discussion and summary of Jurassic and older rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico, and is based on analysis of geophysical logs and observations of outcrops. The Reservation, which is located in the northern San Juan Basin, has been the site of deposition of sediments for much of the Phanerozoic. Geologic times represented on the Reservation are the Precambrian, Cambrian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary, and Quaternary. Rocks of Ordovician and Silurian age have not been reported in this region. Thicknesses of pre-Cretaceous sedimentary rocks range from about 750 feet (229 meters) on the Archuleta arch, east of the Reservation, to more than 8,300 feet (2,530 meters) just northwest of the Reservation. About 5,500 feet (1,676 meters) of pre-Cretaceous sedimentary rocks occur in the central part of the Reservation, near Ignacio. At Ignacio the top of the Jurassic lies at a depth of 7,600 feet (2,316 meters) below the surface, which is composed of Tertiary rocks. As much as 2,500 feet (762 meters) of Tertiary rocks occur in the area. More than 10,000 feet (3,048 meters) of Cretaceous and younger rocks, and 15,600 feet (4,755 meters) of all Phanerozoic sedimentary rocks occur in the vicinity of the Reservation. In the early Paleozoic the area that includes the Southern Ute Reservation was on the stable western shelf of the craton. During this time sediments that compose the following shallow-marine clastic and carbonate rocks were deposited: the Upper Cambrian Ignacio Quartzite (0-150 feet; 0-46 meters), Upper Devonian Elbert Formation (50-200 feet; 15-61 meters), Upper Devonian Ouray Limestone (10-75 feet; 3-23 meters), and Mississippian Leadville Limestone (0-250 feet; 0-76 meters). Mixed carbonate and clastic deposition, which was punctuated by a unique episode of deposition of evaporite sediments, continued through

  13. Geographic names of the Antarctic

    ,; ,; ,; ,; Alberts, Fred G.

    1995-01-01

    This gazetteer contains 12,710 names approved by the United States Board on Geographic Names and the Secretary of the Interior for features in Antarctica and the area extending northward to the Antarctic Convergence. Included in this geographic area, the Antarctic region, are the off-lying South Shetland Islands, the South Orkney Islands, the South Sandwich Islands, South Georgia, Bouvetøya, Heard Island, and the Balleny Islands. These names have been approved for use by U.S. Government agencies. Their use by the Antarctic specialist and the public is highly recommended for the sake of accuracy and uniformity. This publication, which supersedes previous Board gazetteers or lists for the area, contains names approved as recently as December 1994. The basic name coverage of this gazetteer corresponds to that of maps at the scale of 1:250,000 or larger for coastal Antarctica, the off-lying islands, and isolated mountains and ranges of the continent. Much of the interior of Antarctica is a featureless ice plateau. That area has been mapped at a smaller scale and is nearly devoid of toponyms. All of the names are for natural features, such as mountains, glaciers, peninsulas, capes, bays, islands, and subglacial entities. The names of scientific stations have not been listed alphabetically, but they may appear in the texts of some decisions. For the names of submarine features, reference should be made to the Gazetteer of Undersea Features, 4th edition, U.S. Board on Geographic Names, 1990.

  14. Choanoflagellates in the Antarctic Ocean, with special reference to Parvicorbicula socialis (Meunier) Deflandre

    Hara,Shigemitsu/Tanoue,Eiichiro/Zenimoto,Michio/Komaki,Yuzo/Takahashi,Eiji

    1984-01-01

    Distribution and morphology of choanoflagellates, collared heterotrophic flagellates bearing an extracellular siliceous lorica, were reviewed. Eleven species were reported from the Antarctic Ocean. Three of the eleven species were originally described from the Antarctic and are known to be endemic to the Antarctic. The other eight were found in various oceanic areas. Choanoflagellates had been found in both ice and water, which suggested their wide and abundant distribution in the Antarctic. ...

  15. Adjustment of pigment composition in Desmarestia (Desmarestiaceae species along a sub-Antarctic to Antarctic latitudinal gradient

    Andrés Mansilla

    2016-08-01

    Full Text Available Photosynthesis at high latitudes demands efficient strategies of light utilization to maintain algal fitness and performance. The fitness, and physiological adaptation, of a plant or algae species depends in part on the abundance and efficiency of the pigments it can produce to utilize the light resource from its environment. We quantified pigment composition and concentration in six species of the brown macroalgal genus Desmarestia, collected from sub-Antarctic sites (Strait of Magellan, Beagle Channel–Cape Horn Province and sites on the Antarctic Peninsula and adjacent islands. Sub-Antarctic Desmarestia species exhibited lower concentrations of chlorophyll a, chlorophyll c and fucoxanthin than endemic Antarctic species. Antarctic samples of D. menziesii and D. antarctica collected along a decreasing latitudinal gradient showed spatial and interspecific differences in light-harvesting pigment composition. Our results suggest distinct physiological adjustments in Desmarestia species in response to heterogeneous abiotic environmental conditions. The marine sub-Antarctic and Antarctic ecosystems are characterized by harsh environments (e.g., extreme irradiance, photoperiod, temperature, salinity to which the physiology of macroalgal species must adapt.

  16. [Isolation and characteristics of DNA fragments for the region of the tissue plasminogen activator genes and areas adjacent to it in the human genome].

    Sarafanov, A G; Timofeeva, M Ia; Aleshkov, S B; Kupriianova, N S; Bannikov, V M; Zakhar'ev, V M; Baev, A A

    1994-01-01

    Fragments overlapping the tPA gene and its 5'- and 3'-flanking regions were isolated from human liver DNA library cloned in lambda Charon4A vector. A BglII fragment comprising the 3' end and the adjacent genomic region (total length 3.7 kb) was subcloned in plasmid pUC19 and its restriction map was determined. The nucleotide sequence of the 5' region of this fragment was compared with the 3' end region of the tPA gene and the corresponding regions of five published variants of tPA mRNA cDNA from different tissues; discrepancies in seven positions were revealed, which might be caused by intragenomic polymorphism.

  17. Potential areas of ground-water discharge in the Basin and Range carbonate-rock aquifer system, White Pine County, Nevada, and adjacent parts of Nevada and Utah

    U.S. Geological Survey, Department of the Interior — These data represent potential areas of ground-water discharge for selected hydrographic areas in eastern Nevada and western Utah. The data are based on phreatophyte...

  18. Antarctic skuas recognize individual humans.

    Lee, Won Young; Han, Yeong-Deok; Lee, Sang-Im; Jablonski, Piotr G; Jung, Jin-Woo; Kim, Jeong-Hoon

    2016-07-01

    Recent findings report that wild animals can recognize individual humans. To explain how the animals distinguish humans, two hypotheses are proposed. The high cognitive abilities hypothesis implies that pre-existing high intelligence enabled animals to acquire such abilities. The pre-exposure to stimuli hypothesis suggests that frequent encounters with humans promote the acquisition of discriminatory abilities in these species. Here, we examine individual human recognition abilities in a wild Antarctic species, the brown skua (Stercorarius antarcticus), which lives away from typical human settlements and was only recently exposed to humans due to activities at Antarctic stations. We found that, as nest visits were repeated, the skua parents responded at further distances and were more likely to attack the nest intruder. Also, we demonstrated that seven out of seven breeding pairs of skuas selectively responded to a human nest intruder with aggression and ignored a neutral human who had not previously approached the nest. The results indicate that Antarctic skuas, a species that typically inhabited in human-free areas, are able to recognize individual humans who disturbed their nests. Our findings generally support the high cognitive abilities hypothesis, but this ability can be acquired during a relatively short period in the life of an individual as a result of interactions between individual birds and humans.

  19. STATUS AND ASSESSMENT OF WATER QUALITY IN ADJACENT SEA AREAS OF LONGKUN DITCH ESTUARY IN HAIKOU%海口市龙昆沟入海排污口邻近海域水质状况与评价

    黄文国

    2012-01-01

    根据2007-2009年海口市龙昆沟入海口邻近海域的水质监测结果,采用水质单因子污染指数评价法对该海域的水质状况进行分析和评价.结果表明:海口市龙昆沟入海口邻近海域受到无机氮、活性磷酸盐和石油类污染较为严重,化学耗氧量度生化耗氧量也出现轻度污染,排污口邻近海域海水水质环境有恶化的趋势.并且依据分析结果,提出了相应的防治对策.%According to the monitoring results of water quality in the adjacent sea areas of Longkun Ditch Estuary in Haikou from 2007 to 2009 the status analysis and evaluation were made by using the single factor pollution index evaluation method of the sea water quality. The results showed that the adjacent sea areas of Longkun Ditch Estuary in Haikou were polluted seriously by inorganic nitrogen, activated phosphate, and petroleum and the consumption of chemical oxygen and biochemical oxygen also appeared mild pollution. And the sea water environment along the adjacent sea areas tends to be deteriorating. With the above analysis, some corresponding countermeasures for the pollution control were proposed.

  20. Water information bulletin No. 30: geothermal investigations in Idaho. Part 11. Geological, hydrological, geochemical and geophysical investigations of the Nampa-Caldwell and adjacent areas, southwestern Idaho

    Mitchell, J.C. (ed.)

    1981-12-01

    The area under study included approximately 925 sq km (357 sq mi) of the Nampa-Caldwell portion of Canyon County, an area within the central portion of the western Snake River Plain immediately west of Boise, Idaho. Geologic mapping, hydrologic, geochemical, geophysical, including detailed gravity and aeromagnetic surveys, were run to acquire needed data. In addition, existing magnetotelluric and reflection seismic data were purchased and reinterpreted in light of newly acquired data.

  1. Patterns of Distribution of Macro-fauna in Different Types of Estuarine, Soft Sediment Habitats Adjacent to Urban and Non-urban Areas

    Lindegarth, M.; Hoskin, M.

    2001-02-01

    Urban development typically creates a large number of potentially interacting disturbances that may cause impacts on assemblages of animals and plans in estuarine habitats. We tested predictions from the general model that intertidal areas exposed to different types of disturbances have different types of assemblages of benthic macrofauna. Different parts of the Port Hacking Estuary (New South Wales, Australia) are exposed to varying degrees of disturbance by human activities. We predicted that the average structure of assemblages of intertidal animals, and patterns of variability would differ between urban and non-urban areas of Port Hacking. Consistent with previous observations from the literature, there were differences in average structure between urban and non-urban sandy areas. Qualitative differences between abundances of individual taxa in urban and non-urban areas were generally not consistent with previous observations. Differences between assemblages in urban and non-urban areas were not observed in muddy sediments, nor in sediments among mangroves and seagrass. No significant differences in variability was observed between urban and non-urban areas. Two general models may be proposed to explain the observed differences in response to urbanization in different habitats: (1) animals are exposed to different levels or combinations of disturbances in different habitats; or (2) assemblages of animals differ in sensitivity to disturbances among habitats.

  2. Rich and rare—First insights into species diversity and abundance of Antarctic abyssal Gastropoda (Mollusca)

    Schwabe, Enrico; Michael Bohn, Jens; Engl, Winfried; Linse, Katrin; Schrödl, Michael

    2007-08-01

    , and all these 84 species seem endemic to Antarctica south of the Polar Front. Comparing diversity and abundances based on epibenthic sledge samples, there is no clear relationship between Antarctic deep-sea gastropod abundance and species richness with depth. However, both Antarctic and adjacent deep-sea areas are still far from being adequately sampled to allow more comprehensive conclusions.

  3. Reaching for the Horizon: Enabling 21st Century Antarctic Science

    Rogan-Finnemore, M.; Kennicutt, M. C., II; Kim, Y.

    2015-12-01

    The Council of Managers of National Antarctic Programs' (COMNAP) Antarctic Roadmap Challenges(ARC) project translated the 80 highest priority Antarctic and Southern Ocean scientific questionsidentified by the community via the SCAR Antarctic Science Horizon Scan into the highest prioritytechnological, access, infrastructure and logistics needs to enable the necessary research to answer thequestions. A workshop assembled expert and experienced Antarctic scientists and National AntarcticProgram operators from around the globe to discern the highest priority technological needs includingthe current status of development and availability, where the technologies will be utilized in the Antarctic area, at what temporal scales and frequencies the technologies will be employed,and how broadly applicable the technologies are for answering the highest priority scientific questions.Secondly the logistics, access, and infrastructure requirements were defined that are necessary todeliver the science in terms of feasibility including cost and benefit as determined by expected scientific return on investment. Finally, based on consideration of the science objectives and the mix oftechnologies implications for configuring National Antarctic Program logistics capabilities andinfrastructure architecture over the next 20 years were determined. In particular those elements thatwere either of a complexity, requiring long term investments to achieve and/or having an associated cost that realistically can only (or best) be achieved by international coordination, planning and partnerships were identified. Major trends (changes) in logistics, access, and infrastructure requirements were identified that allow for long-term strategic alignment of international capabilities, resources and capacity. The outcomes of this project will be reported.

  4. Digital geologic map data for the Ozark National Scenic Riverways and adjacent areas along the Current River and Jacks Fork, Missouri

    Weary, David J.; Orndorff, Randall C.; Harrison, Richard W.; Weems, Robert E.

    2016-09-23

    The geology of the Ozark National Scenic Riverways (ONSR) in southern Missouri has been mapped at 1:24,000 scale. This endeavor was achieved through the combined efforts of U.S. Geological Survey and Missouri Geological Survey individual quadrangle mapping and additional fieldwork by the authors of this report. Geologic data covering the area of the ONSR and a 1-mile (1.6-kilometer) buffer zone surrounding the park, as well as geologic data from a few key adjoining areas, have been compiled into a single, seamless geographic information system database. The intent is to provide base geologic information for natural science research and land management in the park and surrounding areas. The data are served online at ScienceBase (https://www.sciencebase.gov/catalog/), where they are provided in Environmental Systems Research Institute (ESRI) file geodatabase format, and are accompanied by metadata files. These data can be accessed at: http://dx.doi.org/10.5066/F7CJ8BKB. Additional detailed geologic information about the ONSR and surrounding areas is available in the separate 1:24,000-scale quadrangle maps and in a 1:100,000-scale map and report on the regional geology.

  5. Illegal hunting and law enforcement during a period of economic decline in Zimbabwe: A case study of northern Gonarezhou National Park and adjacent areas

    Gandiwa, E.; Heitkonig, I.M.A.; Lokhorst, A.M.; Prins, H.H.T.; Leeuwis, C.

    2013-01-01

    Illegal hunting of wildlife, or top-down harvesting, is a major issue in today's society, particularly in tropical ecosystems. There has been widespread concern about increasing illegal hunting of wildlife in most conservation areas in Zimbabwe following the political instability and economic declin

  6. NUMERICAL SIMULATION OF SUMMER CIRCULATION IN THE EAST CHINA SEA AND ITS APPLICATION IN ESTIMATING THE SOURCES OF RED TIDES IN THE YANGTZE RIVER ESTUARY AND ADJACENT SEA AREAS

    CHEN Xiu-hua; ZHU Liang-sheng; ZHANG Hong-sheng

    2007-01-01

    Based on the COHERENS (a Coupled Hydrodynamical Ecological model for Regional Shelf seas), a three-dimensional baroclinic model for the summer of East China Sea (ECS) was established with the sigma-coordinate in the vertical direction and spherical coordinate in the horizontal direction. The circulation patterns of the Kuroshio Current, the Taiwan Warm Current (TWC), the Tsushima Current and the Yangtze Diluted Water (YDW) were successfully simulated with this model. The calculated results are fairly consistent with previous observations and studies. Based on this baroclinic current field, the Lagranian particles tracking was simulated to estimate the possible origins of the red tides frequently occurring in the Yangtze River estuary and its adjacent sea areas. If there are "seeds" (cysts) of the red tide algae at the seabed of the Taiwan Strait, the offshore of Fujian and Zhejiang Provinces and the northeast Taiwan Island, those are extremely possible sources of the red tides in the Yangtze River estuary and its adjacent sea areas. Field data are needed to confirm it. Numerical simulation to estimate the source of the red tides is a new application of the Lagrangian transport in the marine ecology.

  7. Dorsal border periaqueductal gray neurons project to the area directly adjacent to the central canal ependyma of the C4-T8 spinal cord in the cat.

    Mouton, L J; Kerstens, L; Van der Want, J; Holstege, G

    1996-11-01

    In a previous study horseradish peroxidase (HRP) injections in the upper thoracic and cervical spinal cord revealed some faintly labeled small neurons at the dorsal border of the periaqueductal gray (PAG). The present light microscopic and electronmicroscopic tracing study describes the precise location of these dorsal border PAG-spinal neurons and their terminal organization. Wheat germ agglutinin-conjugated HRP (WGA-HRP) injections into cervical and upper thoracic spinal segments resulted in several hundreds of small retrogradely labeled neurons at the dorsal border of the ipsilateral caudal PAG. These neurons were not found after injections in more caudal segments. WGA-HRP injections in the dorsal border PAG region surprisingly resulted in anterogradely labeled fibers terminating in the area dorsally and laterally adjoining the central canal ependyma of the C4-T8 spinal cord. No anterogradely labeled fibers were found more caudal in the spinal cord. The labeled fibers found in the upper cervical cord were not located in the area immediately adjoining the ependymal layer of the central canal, but in the lateral part of laminae VI, VII and VIII and in area X bilaterally. Electronmicroscopic results of one case show that the dorsal border PAG-spinal neurons terminate in the neuropil of the subependymal area and in the vicinity of the basal membranes of capillaries located laterally to the central canal. The terminal profiles contain electron-lucent and densecored vesicles, suggesting a heterogeneity of possible transmitters. A striking observation was the lack of synaptic contacts, suggesting nonsynaptic release from the profiles. The function of the dorsal border PAG-spinal projection is unknown, but considering the termination pattern of the dorsal border PAG neurons on the capillaries the intriguing similarity between this projection system and the hypothalamohypophysial system is discussed.

  8. Spatial-Temporal Variations of Chlorophyll-a in the Adjacent Sea Area of the Yangtze River Estuary Influenced by Yangtze River Discharge

    Ying Wang

    2015-05-01

    Full Text Available Carrying abundant nutrition, terrigenous freshwater has a great impact on the spatial and temporal heterogeneity of phytoplankton in coastal waters. The present study analyzed the spatial-temporal variations of Chlorophyll-a (Chl-a concentration under the influence of discharge from the Yangtze River, based on remotely sensed Chl-a concentrations. The study area was initially zoned to quantitatively investigate the spatial variation patterns of Chl-a. Then, the temporal variation of Chl-a in each zone was simulated by a sinusoidal curve model. The results showed that in the inshore waters, the terrigenous discharge was the predominant driving force determining the pattern of Chl-a, which brings the risk of red tide disasters; while in the open sea areas, Chl-a was mainly affected by meteorological factors. Furthermore, a diversity of spatial and temporal variations of Chl-a existed based on the degree of influences from discharge. The diluted water extended from inshore to the east of Jeju Island. This process affected the Chl-a concentration flowing through the area, and had a potential impact on the marine environment. The Chl-a from September to November showed an obvious response to the discharge from July to September with a lag of 1 to 2 months.

  9. 3D crustal seismic velocity model for the Gulf of Cadiz and adjacent areas (SW Iberia margin) based on seismic reflection and refraction profiles

    Lozano, Lucía; Cantavella, Juan Vicente; Barco, Jaime; Carranza, Marta; Burforn, Elisa

    2016-04-01

    The Atlantic margin of the SW Iberian Peninsula and northern Morocco has been subject of study during the last 30 years. Many seismic reflection and refraction profiles have been carried out offshore, providing detailed information about the crustal structure of the main seafloor tectonic domains in the region, from the South Portuguese Zone and the Gulf of Cadiz to the Abyssal Plains and the Josephine Seamount. The interest to obtain a detailed and realistic velocity model for this area, integrating the available data from these studies, is clear, mainly to improve real-time earthquake hypocentral location and for tsunami and earthquake early warning. Since currently real-time seismic location tools allow the implementation of 3D velocity models, we aim to generate a full 3D crustal model. For this purpose we have reviewed more than 50 profiles obtained in different seismic surveys, from 1980 to 2008. Data from the most relevant and reliable 2D seismic velocity published profiles were retrieved. We first generated a Moho depth map of the studied area (latitude 32°N - 41°N and longitude 15°W - 5°W) by extracting Moho depths along each digitized profile with a 10 km spacing, and then interpolating this dataset using ordinary kriging method and generating the contour isodepth map. Then, a 3D crustal velocity model has been obtained. Selected vertical sections at different distances along each profile were considered to retrieve P-wave velocity values at each interface in order to reproduce the geometry and the velocity gradient within each layer. A double linear interpolation, both in distance and depth, with sampling rates of 10 km and 1 km respectively, was carried out to generate a (latitude, longitude, depth, velocity) matrix. This database of all the profiles was interpolated to obtain the P-wave velocity distribution map every kilometer of depth. The new 3D velocity model has been integrated in NonLinLoc location program to relocate several representative

  10. Stable carbon isotopic composition of suspended particulate organic matter in the Prydz Bay and its adjacent areas%南极普里兹湾及其邻近海域悬浮颗粒有机物的碳同位素组成及其影响因素

    任春燕; 陈敏; 高众勇; 郭劳动; 贾仁明; 刘萧; 邱雨生; 郑敏芳

    2015-01-01

    To better understand carbon and particle dynamics in the Prydz Bay and its adjacent areas,stable carbon i-sotopic composition in suspended particulate organic matter (POM)along with aqueous CO2 ,nutrients and hydrog-raphic data were measured to examine the spatial and vertical distributions ofδ13 CPOC and their controlling factors during the 29th Chinese Antarctic Research Expedition.Furthermore,carbon isotope fractionation factor during the assimilation of dissolved inorganic carbon (DIC)by phytoplankton in the mixed layer was estimated.Our results showed thatδ13 CPOC ranged from -28.5‰ to -21.1‰ with an average of -24.6‰,showing an increase trend from the inner bay to open waters outside the Bay.Carbon isotope fractionation factor during phytoplankton DIC assimilation in the mixed layer was estimated to be 23.4‰ based on the relationship between δ13 CPOC and 1/[CO2(aq)],and was the major controlling factor forδ13 CPOC values in the mixed layer in the Prydz Bay and its adja-cent areas.Values ofδ13 CPOC increased in general with increasing depth in the study areas,ascribing to the isotope fractionation during POM remineralization.%依托中国第29次南极科学考察航次开展了南大洋普里兹湾及其邻近海域悬浮颗粒有机物碳同位素组成(δ13 CPOC )的研究,结合温度、盐度、营养盐和溶解 CO2的数据,揭示了影响研究海域颗粒有机物碳同位素组成的主控因素,计算出混合层中浮游植物吸收无机碳过程的碳同位素分馏因子。结果表明,普里兹湾及其邻近海域的δ13 CPOC 介于-28.5‰~-21.1‰,平均值为-24.6‰,表现出湾内大于湾外的特征。浮游植物同化吸收 CO2过程的碳同位素分馏是影响研究海域混合层δ13 CPOC 的主要因素,根据δ13 CPOC和1/[CO2(aq)]的线性拟合关系,计算出浮游植物同化吸收 CO2过程的碳同位素分馏因子εp 为23.4‰。δ13 CPOC的垂直分布随深度

  11. Distribution of organic carbon in sediments and its influences on adjacent sea area in the turbidity maximum of Changjiang Estuary in China

    GAO Jianhua; WANG Yaping; PAN Shaoming; ZHANG Rui; LI Jun; BAI Fenglong

    2008-01-01

    Distributions and sources of total organnic carbon(TOC)in seabed sediments and their implications for hydrodynamics are analyzed,in the turbidity maximum of the Changjiang Estuary.Ecology ecoenvironmental effects of estuary water on the continuously in-creasing terrigenous organic carbon from the Changjiang River are also explored through variations of organic carbon content and water quality indicators.Results show that,hydrodynamics exert important influences on distributions of organic carbon in the tur-bidity maximum of Changjiang Estuary.For their redistribution effect of terrigenous organic carbon within the moving layer in the whole region,variations from land to sea are not indicated by surficial and vertical average values of TOC and total nitrogen(TN) contents in core sediment,as well as organic stable carbon isotopes in surface sediments.However,on the long-time scale,the trend of terrigenous organic carbon decreasing from land to sea is still displayed by variations of stable carbon isotopic average val-ues becoming heavier from land to sea.Previous studies have shown that high content of Chl a cannot appear in the Changjiang Es-tuary in despite of adequate nourishment supply,because photosynthesis of phytoplankton is constrained by high suspended sedi-ment concentration(SSC).However,an area with a high content of Chl a occurs,which may be caused by resuspended benthic algae with bottom fine grain-size sediments.Tremendous pressures are imposed on the environment of Changjiang Estuary,be-cause of ultrophication trends and special hydrodynamics.Phytoplankton bloom area tends to extend from the outer sea to the mouth of Changjiang River.

  12. Spatial and temporal variations and controlling factors of sediment accumulation in the Yangtze River estuary and its adjacent sea area in the Holocene, especially in the Early Holocene

    Feng, Zhibing; Liu, Baohua; Zhao, Yuexia; Li, Xishuang; Jiang, Li; Si, Shaokun

    2016-08-01

    The sub-bottom and collected borehole data provide insight into the transport and accumulation processes of the Yangtze-derived sediment in the study area since ~11 kyr BP. Five seismic units were identified according to six major acoustic surfaces. The sedimentary strata consist of fluvial, estuarine and deltaic systems from the bottom up, characterized by two different trends in sediment accumulation rates, i.e., low-high-low, and high-low-high. On the inner shelf of the East China Sea, the terrain with trough and ridge was formed by the Early Holocene transgression strata (formed in ~10 to 12 kyr BP) scoured by the later rectilinear tidal current due to postglacial sea-level transgression, and the sharply protruding seismic units are interpreted to be bedrocks outcropping on the seafloor. An analysis of the sedimentary characteristics in the boreholes and such factors as difference in accumulation rates, and tectonic subsidence led us to conclude that the paleo-coastline was located not far away from and to the east of Core ZK09 at ~9 kyr BP, and the southern bank of the Yangtze River estuary was located to the south of Core ZK09. At ~9 kyr BP, the Yangtze-derived sediments were transported eastwards along the southern bank of the Yangtze River and the barrier due to the influence of the paleo-coastal current from the north, the direction of the Yangtze-derived sediment transport was split on the northeast of the Zhoushan archipelago, and the sediments covered the terrain with trough and ridge. During the high sea level period (7 kyr BP-present), the eastward migration of paleo-coastline had resulted in the increase in accumulation rate. We also conclude that the sharp increase in accumulation rate near the Yangtze River estuary after ~2 kyr BP was not primarily caused by human activities. The position shifts of the estuary caused by the paleo-coastline migration and sea level oscillations since the Holocene is the main cause controlling the Yangtze

  13. Study area boundary derived from 1:1,000,000-scale hydrographic areas and flow systems for the Great Basin carbonate and alluvial aquifer system of Nevada, Utah, and parts of adjacent states

    U.S. Geological Survey, Department of the Interior — This dataset contains the amalgamation of the hydrographic area (HA) boundaries and polygons for the GBCAAS study area. The study area consists of 165 HAs based on...

  14. Potential effects of groundwater pumping on water levels, phreatophytes, and spring discharges in Spring and Snake Valleys, White Pine County, Nevada, and adjacent areas in Nevada and Utah

    Halford, Keith J.; Plume, Russell W.

    2011-01-01

    Assessing hydrologic effects of developing groundwater supplies in Snake Valley required numerical, groundwater-flow models to estimate the timing and magnitude of capture from streams, springs, wetlands, and phreatophytes. Estimating general water-table decline also required groundwater simulation. The hydraulic conductivity of basin fill and transmissivity of basement-rock distributions in Spring and Snake Valleys were refined by calibrating a steady state, three-dimensional, MODFLOW model of the carbonate-rock province to predevelopment conditions. Hydraulic properties and boundary conditions were defined primarily from the Regional Aquifer-System Analysis (RASA) model except in Spring and Snake Valleys. This locally refined model was referred to as the Great Basin National Park calibration (GBNP-C) model. Groundwater discharges from phreatophyte areas and springs in Spring and Snake Valleys were simulated as specified discharges in the GBNP-C model. These discharges equaled mapped rates and measured discharges, respectively. Recharge, hydraulic conductivity, and transmissivity were distributed throughout Spring and Snake Valleys with pilot points and interpolated to model cells with kriging in geologically similar areas. Transmissivity of the basement rocks was estimated because thickness is correlated poorly with transmissivity. Transmissivity estimates were constrained by aquifer-test results in basin-fill and carbonate-rock aquifers. Recharge, hydraulic conductivity, and transmissivity distributions of the GBNP-C model were estimated by minimizing a weighted composite, sum-of-squares objective function that included measurement and Tikhonov regularization observations. Tikhonov regularization observations were equations that defined preferred relations between the pilot points. Measured water levels, water levels that were simulated with RASA, depth-to-water beneath distributed groundwater and spring discharges, land-surface altitudes, spring discharge at

  15. Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2015

    Beman, Joseph E.; Bryant, Christina F.

    2016-10-27

    The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is hydrologically defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift between San Acacia to the south and Cochiti Lake to the north. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when the Albuquerque Bernalillo County Water Utility Authority (ABCWUA) began treatment and distribution of surface water from the Rio Grande through the San Juan-Chama Drinking Water Project. A 20-percent population increase in the basin from 1990 to 2000 and a 22-percent population increase from 2000 to 2010 may have resulted in an increased demand for water in areas within the basin.An initial network of wells was established by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque from April 1982 through September 1983 to monitor changes in groundwater levels throughout the Albuquerque Basin. In 1983, this network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly. The network currently (2015) consists of 124 wells and piezometers. (A piezometer is a specialized well open to a specific depth in the aquifer, often of small diameter and nested with other piezometers open to different depths.) The USGS, in cooperation with the ABCWUA, currently (2015) measures and reports water levels from the 124 wells and piezometers in the network; this report presents water-level data collected by USGS personnel at those 124 sites through water year 2015 (October 1, 2014, through September 30, 2015).

  16. The Fourth Geodetic Surveying Campaign on Mt. Everest and its Adjacent Area%珠峰及邻近区域第四次大地测量

    张全德; 陈俊勇; 庞尚益; 张骥; 王泽民

    2001-01-01

    The fourth geodetic surveying campaign on Mt. Everest and itsadjacent area was successfully conducted by Chinese surveyors in 1998. Its fieldwork introductions, data acquisitions, data processing methods and the final results achieved were described in this paper. A thoroughly scientific Analyse based on comparing the 4-session geodetic surveying observations which were conducted in 1998, 1992,1975 and 1966-1968 respectively shows that Qinghai-Tibet Block is still moving on its way of northeast horizontally under the motivation caused by Indian Block movement, while relative vertical movement has waving fluctuation during the entire rising process.%叙述了我国大地测量工作者于1998年对珠穆朗玛峰及邻近区域进行的第四次大规模的大地测量外业概况和取得的成果,以及数据处理方法和最终结果。经过对1998、1966-1968、1975、1992年珠峰及邻近区域四次大地测量数据综合分析,从地学方面进行研究,得出青藏块体在印度板块的推动下,仍向北东东方向运动;珠峰地区相对垂直运动在整体抬升的过程中伴有波浪式的起伏等结论。

  17. Phytoplankton and nutrient distributions in a front-eddy area adjacent to the coastal upwelling zone off Concepcion (Chile): implications for ecosystem productivity.

    Morales, Carmen; Anabalón, Valeria; Hormazábal, Samuel; Cornejo, Marcela; Bento, Joaquim; Silva, Nelson

    2016-04-01

    The impact that sub-mesoscale (1-10 km) to mesocale (50-100 km) oceanographic variability has on plankton and nutrient distributions (horizontal and vertical) in the coastal upwelling and transition zones off Concepcion was the focus of this study. Satellite time-series data (wind, sea-surface temperature (SST), and altimetry) were used to understand the dynamic context of in situ data derived from a short-term front survey (3 d) during the upwelling period (3-6 February, 2014). The survey included two transects perpendicular to the coast, covering the shelf and shelf-break areas just north of Punta Lavapie, a main upwelling center (˜37° S). Wind and SST time-series data indicated that the survey was undertaken just after a moderate upwelling event (end of January) which lead to a relaxation phase during early February. A submesoscale thermal front was detected previous to and during the survey and results from an eddy tracking algorithm based on altimetry data indicated that this front (F1) was flanked on its oceanic side by an anticyclonic, mesoscale eddy (M1), which was ˜25 d old at the sampling time. M1 strengthened the thermal gradient of F1 by bringing warmer oceanic water nearer to the colder coastal upwelling zone. The distributions of hydrographic variables and nutrients in the water column (interaction creates a complex field of submesoscale processes in the top layer, including vertical nutrient injections and lateral stirring, which contributes to the exportation of coastal communities to the open ocean in this region. We discuss how this interaction might affect ecosystem productivity in the coastal band.

  18. Mapping the hydraulic connection between a coalbed and adjacent aquifer: example of the coal-seam gas resource area, north Galilee Basin, Australia

    Jiang, Zhenjiao; Mariethoz, Gregoire; Schrank, Christoph; Cox, Malcolm; Timms, Wendy

    2016-12-01

    Coal-seam gas production requires groundwater extraction from coal-bearing formations to reduce the hydraulic pressure and improve gas recovery. In layered sedimentary basins, the coalbeds are often separated from freshwater aquifers by low-permeability aquitards. However, hydraulic connection between the coalbed and aquifers is possible due to the heterogeneity in the aquitard such as the existence of conductive faults or sandy channel deposits. For coal-seam gas extraction operations, it is desirable to identify areas in a basin where the probability of hydraulic connection between the coalbed and aquifers is low in order to avoid unnecessary loss of groundwater from aquifers and gas production problems. A connection indicator, the groundwater age indictor (GAI), is proposed, to quantify the degree of hydraulic connection. The spatial distribution of GAI can indicate the optimum positions for gas/water extraction in the coalbed. Depressurizing the coalbed at locations with a low GAI would result in little or no interaction with the aquifer when compared to the other positions. The concept of GAI is validated on synthetic cases and is then applied to the north Galilee Basin, Australia, to assess the degree of hydraulic connection between the Aramac Coal Measure and the water-bearing formations in the Great Artesian Basin, which are separated by an aquitard, the Betts Creek Beds. It is found that the GAI is higher in the western part of the basin, indicating a higher risk to depressurization of the coalbed in this region due to the strong hydraulic connection between the coalbed and the overlying aquifer.

  19. An automated methodology for differentiating rock from snow, clouds and sea in Antarctica from Landsat 8 imagery: a new rock outcrop map and area estimation for the entire Antarctic continent

    Burton-Johnson, Alex; Black, Martin; Fretwell, Peter T.; Kaluza-Gilbert, Joseph

    2016-08-01

    As the accuracy and sensitivity of remote-sensing satellites improve, there is an increasing demand for more accurate and updated base datasets for surveying and monitoring. However, differentiating rock outcrop from snow and ice is a particular problem in Antarctica, where extensive cloud cover and widespread shaded regions lead to classification errors. The existing rock outcrop dataset has significant georeferencing issues as well as overestimation and generalisation of rock exposure areas. The most commonly used method for automated rock and snow differentiation, the normalised difference snow index (NDSI), has difficulty differentiating rock and snow in Antarctica due to misclassification of shaded pixels and is not able to differentiate illuminated rock from clouds. This study presents a new method for identifying rock exposures using Landsat 8 data. This is the first automated methodology for snow and rock differentiation that excludes areas of snow (both illuminated and shaded), clouds and liquid water whilst identifying both sunlit and shaded rock, achieving higher and more consistent accuracies than alternative data and methods such as the NDSI. The new methodology has been applied to the whole Antarctic continent (north of 82°40' S) using Landsat 8 data to produce a new rock outcrop dataset for Antarctica. The new data (merged with existing data where Landsat 8 tiles are unavailable; most extensively south of 82°40' S) reveal that exposed rock forms 0.18 % (21 745 km2) of the total land area of Antarctica: half of previous estimates.

  20. Seismotectonic Map of Afghanistan and Adjacent Areas

    Wheeler, Russell L.; Rukstales, Kenneth S.

    2007-01-01

    Introduction This map is part of an assessment of Afghanistan's geology, natural resources, and natural hazards. One of the natural hazards is from earthquake shaking. One of the tools required to address the shaking hazard is a probabilistic seismic-hazard map, which was made separately. The information on this seismotectonic map has been used in the design and computation of the hazard map. A seismotectonic map like this one shows geological, seismological, and other information that previously had been scattered among many sources. The compilation can show spatial relations that might not have been seen by comparing the original sources, and it can suggest hypotheses that might not have occurred to persons who studied those scattered sources. The main map shows faults and earthquakes of Afghanistan. Plate convergence drives the deformations that cause the earthquakes. Accordingly, smaller maps and text explain the modern plate-tectonic setting of Afghanistan and its evolution, and relate both to patterns of faults and earthquakes.

  1. Modelling the Antarctic Ice Sheet

    Pedersen, Jens Olaf Pepke; Holm, A.

    2015-01-01

    The Antarctic ice sheet is a major player in the Earth’s climate system and is by far the largest depository of fresh water on the planet. Ice stored in the Antarctic ice sheet (AIS) contains enough water to raise sea level by about 58 m, and ice loss from Antarctica contributed significantly...... Science) Antarctic Ice Sheet (DAIS) model (Shaffer 2014) is forced by reconstructed time series of Antarctic temperature, global sea level and ocean subsurface temperature over the last two glacial cycles. In this talk a modelling work of the Antarctic ice sheet over most of the Cenozoic era using...... the DAIS model will be presented. G. Shaffer (2014) Formulation, calibration and validation of the DAIS model (version 1), a simple Antarctic ice sheet model sensitive to variations of sea level and ocean subsurface temperature, Geosci. Model Dev., 7, 1803‐1818...

  2. A Comparative Study of Antarctic Arctic and Himalayan Ice

    R. C. Pathak

    1989-07-01

    Full Text Available Arctic, Antarctic and inaccessible lofty regions of Himalayas,which are geographically diverse areas and have been a constant source of inspiration, envisages a challenging field of study 'by early adventurers and scientists of the world. Characteristics of ice obtained at Arctic and Antarctic do not possess similar properties. Even thesalient properties of snow and ice of western and central Himalayas vary due to its differing free water content. A study has been carriedout based on recent Antarctic Expedition by Indian scientists and the data gathered along litha-tectonic regions of Himalayas and their characteristics have been compared, wkich brings out stratigraphic and metamorphic characteristics of the ice and snow. In the present paper,an analysis of the ice and snow properties of Arctic, Antarctic and Himalayan regions has been presented.

  3. Viruses in Antarctic lakes

    Kepner, R. L. Jr; Wharton, R. A. Jr; Suttle, C. A.; Wharton RA, J. r. (Principal Investigator)

    1998-01-01

    Water samples collected from four perennially ice-covered Antarctic lakes during the austral summer of 1996-1997 contained high densities of extracellular viruses. Many of these viruses were found to be morphologically similar to double-stranded DNA viruses that are known to infect algae and protozoa. These constitute the first observations of viruses in perennially ice-covered polar lakes. The abundance of planktonic viruses and data suggesting substantial production potential (relative to bacteria] secondary and photosynthetic primary production) indicate that viral lysis may be a major factor in the regulation of microbial populations in these extreme environments. Furthermore, we suggest that Antarctic lakes may be a reservoir of previously undescribed viruses that possess novel biological and biochemical characteristics.

  4. 柴达木盆地及其邻区早—中二叠世构造-岩相古地理格局%Early-middle Permian Tectonic-lithofacies Palaeogeographic Characteristics in Qaidam Basin and Its Adjacent Areas

    陈守建; 陈奋宁; 计文化; 李荣社; 洛长义; 刘荣利; 李国栋

    2012-01-01

    通过大量野外观察、分析测试和综合研究,结合覆盖全区不同比例尺的区域地质调查资料,对柴达木盆地及其邻区早—中二叠世构造-岩相古地理格局进行了研究,并探讨了其形成机制.结果表明:柴达木盆地及其邻区中、北部早—中二叠世为陆内盆山-裂谷系统,主体处于伸展构造背景,总体表现为堑垒相间的构造古地理格局;南部为巴颜喀拉洋盆,早—中二叠世是巴颜喀拉洋盆扩张最为剧烈且规模最大的时期,巴颜喀拉洋盆中洋岛、海山遍布;早—中二叠世晚期强烈的华力西构造运动使古板块间的相对运动加剧,巴颜喀拉洋盆大洋岩石圈板块向北强烈俯冲,形成东昆仑陆缘岩浆弧及其南部增生带,东昆仑陆缘岩浆弧岩浆活动十分强烈,宗务隆山—西秦岭陆源裂谷盆地进一步发育,形成十分复杂的构造-岩相古地理格局.早—中二叠世是研究区地球动力学机制从强烈扩张到强烈汇聚的转折时期,加强其构造-岩相古地理研究对建立该区地层序列、探讨其地质演化历史以及指导找矿等均具有重要意义.%Through the field observation, the analysis of test data, the comprehensive regional geological survey and the previous research result, the forming mechanism and tectonic-lithofacies paleogeography during the Early-middle Permian in Qaidam Basin and its adjacent areas were discussed. The results showed that the Early-middle Permian in the central and northern parts of Qaidam Basin and its adjacent areas was intracontinental basin-and-range and rift valley system, and mainly located on extensional tectonic setting, and the tectonic paleogeography was graben and horst alternately! the Early-middle Permian in the southern part was the period with most violent expansion cosmically in Bayankala ocean basin, and ocean-island and seamount were all over the ocean basinj the strong Hualixi tectonic movement in the late of Early

  5. 重庆及邻区震后烈度分布评估模型构建%Study on Model Building of Post-earthquake Intensity in Chongqing and Its Adjacent Areas

    秦娟; 蔡辉腾; 李光; 王宏超

    2013-01-01

    After an earthquake,the earthquake disaster rapid assessment team needs very detailed information,such as an intensity distribution map.If we can study several kinds of different intensity distribution evaluation models in support of the emergency database and compare the difference between disaster evaluation results from different models,the final result will have greater credibility.In this study,the research area of focus was Chongqing and its adjacent areas.The research analyzed 19 earthquakes since 1960,collected and digitized 19 seismic intensity isoseismal maps,and acquired a total of 46 isoseismal data sets,including long axis,short axis,and total area,for a data total of 141.In accordance with the characteristics of historical isoseismals,the isoseismals were processed as ovals.In this study,the researcher looked at the epicenter distribution of earthquakes in Chongqing and the vicinity,the intensity data,and the distribution of seismic magnitude and intensity.Through regression analysis,an intensity distribution evaluation model was developed on the basis of the seismic intensity attenuation relationship,and the results from the model were compared with those from other models,which yielded a figure representing the comparison.The attenuation relationship of the earthquake in Chongqing and its adjacent area was compared with Suyun Wang,in China’s eastern region; Jianqi Lu,in a moderate earthquake area,and Jiancheng Lei,in Sichuan Basin.To make the seismic intensity attenuation curve closer to the actual situation with respect to far-field and near-field intensity,additional measures were needed to improve the distribution of the data.Hence,the author developed intensity distribution evaluation models based on the length of the prolate axis and the minor axis,and area statistics.The author developed different fitting curves for(1)magnitude Ⅴ long shaft fitting,(2)magnitude Ⅴ short axial fitting,(3)magnitude Ⅵ long shaft fitting,and(4)magnitude

  6. At-Sea Distribution and Prey Selection of Antarctic Petrels and Commercial Krill Fisheries.

    Descamps, Sébastien; Tarroux, Arnaud; Cherel, Yves; Delord, Karine; Godø, Olaf Rune; Kato, Akiko; Krafft, Bjørn A; Lorentsen, Svein-Håkon; Ropert-Coudert, Yan; Skaret, Georg; Varpe, Øystein

    2016-01-01

    Commercial fisheries may impact marine ecosystems and affect populations of predators like seabirds. In the Southern Ocean, there is an extensive fishery for Antarctic krill Euphausia superba that is projected to increase further. Comparing distribution and prey selection of fishing operations versus predators is needed to predict fishery-related impacts on krill-dependent predators. In this context, it is important to consider not only predators breeding near the fishing grounds but also the ones breeding far away and that disperse during the non-breeding season where they may interact with fisheries. In this study, we first quantified the overlap between the distribution of the Antarctic krill fisheries and the distribution of a krill dependent seabird, the Antarctic petrel Thalassoica antarctica, during both the breeding and non-breeding season. We tracked birds from the world biggest Antarctic petrel colony (Svarthamaren, Dronning Maud Land), located >1000 km from the main fishing areas, during three consecutive seasons. The overall spatial overlap between krill fisheries and Antarctic petrels was limited but varied greatly among and within years, and was high in some periods during the non-breeding season. In a second step, we described the length frequency distribution of Antarctic krill consumed by Antarctic petrels, and compared this with results from fisheries, as well as from diet studies in other krill predators. Krill taken by Antarctic petrels did not differ in size from that taken by trawls or from krill taken by most Antarctic krill predators. Selectivity for specific Antarctic krill stages seems generally low in Antarctic predators. Overall, our results show that competition between Antarctic petrels and krill fisheries is currently likely negligible. However, if krill fisheries are to increase in the future, competition with the Antarctic petrel may occur, even with birds breeding thousands of kilometers away.

  7. The Influence of Urbanism and Information Consumption on Political Dimensions of Social Capital: Exploratory Study of the Localities Adjacent to the Core City from Brașov Metropolitan Area, Romania

    Rezeanu, Cătălina-Ionela; Briciu, Arabela; Briciu, Victor; Repanovici, Angela; Coman, Claudiu

    2016-01-01

    Background The last two decades have seen a growing trend towards the research of voting behavior in post-communist countries. Urban sociology theorists state that not only space structures influence political participation, but also space structures are changing under the influence of global, local, and individual factors. The growing role played by information in the globalised world has accelerated the paradigm shift in urban sociology: from central place model (based on urban-rural distinction and on monocentric metropolitan areas) to network society (based on space of flows and polycentric metropolitan areas). However, recent studies have mainly focused on countries with solid democracies, rather than on former communist countries. The present study aims to analyze the extent to which a new emerging spatial structure can be envisaged within a metropolitan area of Romania and its consequences for the political dimensions of social capital. Methods The Transilvania University Ethics Commission approved this study (S1 Aprouval). The research is based upon individual and aggregate empirical data, collected from the areas adjacent to the core city in Brașov metropolitan area. Individual data has been collected during October 2012, using the oral survey technique (S1 Survey), based on a standardized questionnaire (stratified simple random sample, N = 600). The National Institute of Statistics and the Electoral Register provided the aggregate data per locality. Unvaried and multivariate analyses (hierarchical regression method) were conducted based on these data. Results Some dimensions of urbanism, identified as predictors of the political dimensions of social capital, suggest that the area under analysis has a predominantly monocentric character, where the rural-urban distinction continues to remain relevant. There are also arguments favoring the dissolution of the rural-urban distinction and the emergence of polycentric spatial structures. The presence of some

  8. Antarctic, Sub-Antarctic and cold temperate echinoid database

    Benjamin Pierrat

    2012-06-01

    Full Text Available This database includes spatial data of Antarctic, Sub-Antarctic and cold temperate echinoid distribution (Echinodermata: Echinoidea collected during many oceanographic campaigns led in the Southern Hemisphere from 1872 to 2010. The dataset lists occurrence data of echinoid distribution south of 35°S latitude, together with information on taxonomy (from species to genus level, sampling sources (cruise ID, sampling dates, ship names and sampling sites (geographic coordinates and depth. Echinoid occurrence data were compiled from the Antarctic Echinoid Database (David et al., 2005a, which integrates records from oceanographic cruises led in the Southern Ocean until 2003. This database has been upgraded to take into account data from oceanographic cruises led after 2003. The dataset now reaches a total of 6160 occurrence data that have been checked for systematics reliability and consistency. It constitutes today the most complete database on Antarctic and Sub-Antarctic echinoids.

  9. Geothermal investigations in Idaho. Part 12. Stable isotopic evaluation of thermal water occurrences in the Weiser and Little Salmon River drainage basins and adjacent areas, west-central Idaho with attendant gravity and magnetic data on the Weiser area

    Mitchell, J.C.; Bideganeta, K.; Palmer, M.A.

    1984-12-01

    Fifteen thermal springs, two thermal wells, and eight cold springs in the Weiser and Little Salmon river drainages were sampled for deuterium and oxygen-18 analysis during the fall of 1981. The straight-line fit of delta D and delta /sup 18/O versus latitude and longitude observed in the data is what would be expected if the recharge areas for the thermal and non-thermal waters were in close proximity to their respective discharge points. The discrete values of delta D and delta /sup 18/O for each thermal discharge suggest that none of the sampled thermal systems have common sources. The depleted deuterium and oxygen-18 contents of most thermal relative to non-thermal waters sampled suggests that the thermal waters might be Pleistocene age precipitation. The isotopic data suggest little or no evidence for mixing of thermal and non-thermal water for the sampled discharges. Thermal waters from Weiser, Crane Creek, Cove Creek, and White Licks hot springs show enrichment in oxygen-18 suggesting that these waters have been at elevated temperatures relative to other sampled thermal discharges in the area. Gravity and magnetic data gathered by the Idaho State University Geology Department in the Weiser Hot Springs area suggest that southeastward plunging synclinal-anticlinal couples, which underlie the hot springs, are cut south of the springs by a northeast trending boundary fault.

  10. Unveiling the Antarctic subglacial landscape.

    Warner, Roland; Roberts, Jason

    2010-05-01

    Better knowledge of the subglacial landscape of Antarctica is vital to reducing uncertainties regarding prediction of the evolution of the ice sheet. These uncertainties are associated with bedrock geometry for ice sheet dynamics, including possible marine ice sheet instabilities and subglacial hydrological pathways (e.g. Wright et al., 2008). Major collaborative aerogeophysics surveys motivated by the International Polar Year (e.g. ICECAP and AGAP), and continuing large scale radar echo sounding campaigns (ICECAP and NASA Ice Bridge) are significantly improving the coverage. However, the vast size of Antarctica and logistic difficulties mean that data gaps persist, and ice thickness data remains spatially inhomogeneous. The physics governing large scale ice sheet flow enables ice thickness, and hence bedrock topography, to be inferred from knowledge of ice sheet surface topography and considerations of ice sheet mass balance, even in areas with sparse ice thickness measurements (Warner and Budd, 2000). We have developed a robust physically motivated interpolation scheme, based on these methods, and used it to generate a comprehensive map of Antarctic bedrock topography, using along-track ice thickness data assembled for the BEDMAP project (Lythe et al., 2001). This approach reduces ice thickness biases, compared to traditional inverse distance interpolation schemes which ignore the information available from considerations of ice sheet flow. In addition, the use of improved balance fluxes, calculated using a Lagrangian scheme, eliminates the grid orientation biases in ice fluxes associated with finite difference methods (Budd and Warner, 1996, Le Brocq et al., 2006). The present map was generated using a recent surface DEM (Bamber et al., 2009, Griggs and Bamber, 2009) and accumulation distribution (van de Berg et al., 2006). Comparing our results with recent high resolution regional surveys gives confidence that all major subglacial topographic features are

  11. Shackleton: His Antarctic Writings

    Dalrymple, Paul C.

    Two books entitled “Shackleton” were published in the United Kingdom in recent years. The one entitled Shackleton: His Antarctic Writings, Selected and Introduced by Christopher Ralling was published by the British Broadcasting Corporation (BBC) in 1983; the other, by Roland Huntford and simply entitled Shackleton, was published by Hodder and Stoughton (London) in November 1985. The only two things that these books have in common are their title and home publication base: The BBC book is essentially excerpts from two well-known books written by Shackleton, with a strong assist from a New Zealand reporter, Edward Saunders (who served as Shackleton's amanuensis), whereas Huntford's book is an outstanding polar biography.

  12. Caracterização da comunidade liquênica corticícola de Porto Alegre e áreas adjacentes, RS, Brasil Characterization of the corticolous lichen community from Porto Alegre and adjacent areas, RS, Brazil

    Márcia Isabel Käffer

    2011-12-01

    Full Text Available Liquens são organismos em simbiose que habitam os mais diversos ambientes, entretanto em regiões urbanizadas a comunidade liquênica pode ser modificada devido à influência de fatores antrópicos. O objetivo deste trabalho é analisar a composição da comunidade liquênica corticícola na cidade de Porto Alegre e áreas adjacentes, assim como verificar a freqüência, cobertura e valor de importância dos táxons, apresentando uma chave de identificação para as espécies urbanas. Foram analisadas 300 forófitas distribuídas em 30 estações de amostragem divididas em 33 bairros da cidade. Foram registrados 144 táxons liquênicos com prováveis três novos registros para a ciência e dois novos registros para o Estado do Rio Grande do Sul. As espécies mais importantes na comunidade foram Canoparmelia texana (Tuck. Elix & Hale e Dirinaria picta (Sw. Schaer. ex Clem, as quais apresentaram os maiores valores de importância, freqüência e cobertura. O grande número de táxons encontrados nas áreas analisadas representa uma contribuição significante para as pesquisas na área da liquenologia, principalmente por serem utilizados em programas de monitoramento da qualidade do ar, bem como para avaliar a estrutura de ecossistemas florestais.Lichens are symbiotic organisms found in a variety of habitats; however, in urban areas the lichen community can be altered due to the influence of anthropogenic factors. This study aimed to analyze the corticolous lichen community composition in Porto Alegre and adjacent areas, as well as to investigate the frequency, coverage and importance value of the reported taxa. A key to the urban species is also provided. Three hundred phorophytes distributed in 30 sampling stations, divided among 33 city districts, were analyzed. One hundred and forty-four taxa of lichenized fungi were recorded with three probable new citations for Brazil and two new records for Rio Grande do Sul State. The most important

  13. GM 测高数据反演中国近海及邻域精细重力场%Refined marine gravity field of the China’s seas and its adjacent area derived from GM altimeter data

    张胜军; 李建成; 王立伟; 孔祥雪

    2014-01-01

    The advanced threshold method was selected for processing the Jason-1 geodetic mission waveform data based on the comparative analysis of four waveform retracking methods.Combined with the retracked ERS-1 and Geosat geodetic mission data,the along-track data were resampled at 2Hz to improve the spatial resolution of coast-al areas.Considering the influence of sea surface topography after the data quality control process,a refined 1′×1′resolution gravity field of the China sea and its adjacent sea areas(0°~45°N,100°~140°E)was obtained by remove-restore method and Vening-Meinesz formula.The validation with shipborne data showed that the accuracy of in-version result is about 4 mGal and 10 mGal in open seas and shallow water areas,respectively.Moreover,the inver-sion result is better than both of the DTU10 model and the V21.1 model.%综合对比4种波形重跟踪算法,选择改进阈值法处理 Jason-1 GM 数据,联合波形重跟踪后的Geosat 和 ERS-1 GM 数据,沿轨2 Hz 重采样以提高数据空间分辨率。通过数据质量控制剔除粗差数据,考虑海表面地形的影响,基于移去-恢复法和维宁-曼齐兹公式反演了中国近海及邻近海域(0°~45° N,100°~140°E)1′×1′的精细重力场。船测数据检核表明反演结果在开阔海域精度约4 mGal,近岸浅水区约10 mGal,均优于 DTU10和 V21.1模型。

  14. High Prevalence of Gammaproteobacteria in the Sediments of Admiralty Bay and North Bransfield Basin, Northwestern Antarctic Peninsula

    Franco, Diego C.; Signori, Camila N.; Duarte, Rubens T. D.; Nakayama, Cristina R.; Campos, Lúcia S.; Pellizari, Vivian H.

    2017-01-01

    Microorganisms dominate most Antarctic marine ecosystems, in terms of biomass and taxonomic diversity, and play crucial role in ecosystem functioning due to their high metabolic plasticity. Admiralty Bay is the largest bay on King George Island (South Shetland Islands, Antarctic Peninsula) and a combination of hydro-oceanographic characteristics (bathymetry, sea ice and glacier melting, seasonal entrance of water masses, turbidity, vertical fluxes) create conditions favoring organic carbon deposition on the seafloor and microbial activities. We sampled surface sediments from 15 sites across Admiralty Bay (100–502 m total depth) and the adjacent North Bransfield Basin (693–1147 m), and used the amplicon 454-sequencing of 16S rRNA gene tags to compare the bacterial composition, diversity, and microbial community structure across environmental parameters (sediment grain size, pigments and organic nutrients) between the two areas. Marine sediments had a high abundance of heterotrophic Gammaproteobacteria (92.4% and 83.8% inside and outside the bay, respectively), followed by Alphaproteobacteria (2.5 and 5.5%), Firmicutes (1.5 and 1.6%), Bacteroidetes (1.1 and 1.7%), Deltaproteobacteria (0.8 and 2.5%) and Actinobacteria (0.7 and 1.3%). Differences in alpha-diversity and bacterial community structure were found between the two areas, reflecting the physical and chemical differences in the sediments, and the organic matter input. PMID:28210255

  15. 腹股沟及其周围疝所致肠梗阻CT诊断%CT Diagnosis of Intestinal Obstruction Caused by Hernias in Inguinal Canal and Adjacent Areas

    缪小芬; 陆健; 石甜甜; 张学琴; 朱纪吾

    2012-01-01

    Purpose To evaluate the diagnostic value of intestinal obstruction caused by hernias of CT. Materials and Methods CT features of 17 cases with intestinal obstruction caused by hernias in inguinal canal and adjacent areas confirmed by surgery were retrospectively analyzed. All 17 cases underwent abdominal plain, arterial phase and portal phase CT scan. Results All 17 cases demonstrated different degrees of obstruction. In 9 cases with inguinal hernia, CT showed bowel in the hernia sac located lateral to inferior epigastric artery and anterior to the inguinal ligament, passing the inguinal canal. In 1 case with direct hernia, dilated bowel loops protruding anteriorly through Hesselback triangle medial to the inferior epigastric artery without entering the scrotal sac. In 3 cases with femoral hernia, CT showed hernia sac located in femoral triangle and posterior to the pubic tubercle, below the inguinal ligament. In 4 cases with obturator hernia, CT showed bowel loops between obturator externus and pubic muscle, connecting to intra-abdominal bowel. Conclusion CT is able to diagnose intestinal obstruction caused by hernia in inguinal canal and adjacent areas.%目的 探讨CT对腹股沟及其周围疝所致肠梗阻的诊断价值.资料与方法 回顾性分析17例经手术证实的腹股沟及其周围疝所致肠梗阻的CT表现,CT检查包括全腹部平扫、动脉期及门脉期增强.结果 17例患者均有不同程度的肠梗阻表现,腹股沟斜疝9例,CT表现为疝囊内肠管从腹壁下动脉外侧、腹股沟韧带前上方走行,行经腹股沟管内;直疝1例,CT表现为扩张的小肠肠管从腹壁下动脉内侧的直疝三角区(Hesselback三角)直接由后向前突出,疝囊不进入阴囊;股疝3例,CT表现为股疝疝囊位于股三角区、耻骨结节水平线以后、腹股沟韧带后下方;闭孔疝4例,CT表现为闭孔外肌与耻骨肌之间的肠管影和腹部肠管相连.结论 CT检查能明确诊断腹股沟及其周围疝所致肠梗阻.

  16. The Regional Objective Precipitation Forecast in North China and Adjacent Areas in Summer%华北及周边地区夏季分区客观降水预报

    赵翠光; 赵声蓉

    2011-01-01

    North China is one of three major summer rainfall areas in eastern China. Precipitation over North China shows the characteristics of obvious emergency and locality. According to the statistics, 80%-90% precipitation occurs in June-August. Sometimes daily precipitation of a rainstorm can account for 50% precipitation amount of that month. Therefore, effective forecast is crucial especially for larger magnitude precipitation. Objective precipitation forecast is a difficult problem in NWP products interpretation at present. Objective precipitation forecast models are always established station by station, but larger magnitude precipitation is rare event for individual station. It is difficult to establish an effective forecast equation for an individual station. Precipitation intensity, spatial and temporal distribution over North China has its own particularity. Due to the regional characteristic, it is difficult to summarize in one model. Objective partitioning can be used in establishment of precipitation forecast model. Similar samples in the weather region are combined together. Regional forecast model is more stable than single-station forecast model, as the number of large-class precipitation samples increases.Seven weather divisions for summer precipitation over North China and adjacent areas are developed through Rotated Empirical Orthogonal Function (REOF) method, defined by the large contours of the seven REOF models. Objective precipitation forecast is based on probability regression precipitation categorical forecast. First, original precipitation is converted to 0 and 1 corresponding categories, and then forecast equations of different categories are developed to calculate each criterions. In real forecasting, the categorical precipitation will be determined through the criterion and the probability forecast of that category. Based on the daily precipitation data of station and T213 NWP products during the summer of 2006-2008, precipitation forecast

  17. ZOOPLANKTON COMMUNITY STRUCTURE IN YANGTZE RIVER ESTUARY AND ADJACENT SEA AREA IN SUMMER 2006%2006年夏季长江口及其邻近水域浮游动物的群落结构

    陈洪举; 刘光兴

    2009-01-01

    Zooplankton was studied on a cruise ship in the Yangtze River Estuary and adjacent sea area in Jun 2006. Water zooplankton composition, abundance and dominant species were studied. Zooplankton community structure and its influencing factors were studied with multivariate analysis based on sample data and environmental parameters. The work provides fundamental information for long-term monitoring of zooplankton ecology in the Yangtze River Estuary and adjacent sea area. A total of 322 zooplankton species (including 27 pelagic larvae) were identified as a result of the survey. Crustacea and Cnidaria were the two most abundant components among the identified groups. The number of species of pelagic Crustacea represented more than 50% of total species richness, Copepoda was the most important component. Calanus sinicus was the dominant species in the waters. According to species composition and abundance, five assemblages or communities were differentiated for the zooplankton by cluster analysis. Community Ⅰ was a freshwater community, dominated by Sinocalanus dorrii, Schmackeria forbesi; Community Ⅱ lay in the neighborhood of the Yangtze River mouth, dominated by Schmackeria poplesia, Labidocera euchaeta , Tortanus vermiculus; Community Ⅲ belong to the central water of the Yellow Sea community, dominated by C. sinicus, Corycaeus affinis, C. dahli, Sagitta nagae; Community Ⅳ was dominated by C. sinicus, Euchaeta plana , S. nagae, Doliolum denticulatum; Community Ⅴ was dominated by Evadne tergestina, Euconchoecia aculeata, C. sinicus, E. plana, E. concinna, Dolioetta gegenbauri, D. denticulatum. Salinity was the primary abiotic factor influencing zooplankton distribution and abundance in the surveyed waters.%利用2006年6月在长江口及邻近海域进行的大面调查所采集的浮游动物样品,结合环境参数,对长江河口及邻近海域浮游动物种类组成及群落结构进行了多元分析,研究了浮游动物群落结构及其影响因

  18. An Antarctic hot spot for fungi at Shackleton's historic hut on Cape Royds.

    Blanchette, Robert A; Held, Benjamin W; Arenz, Brett E; Jurgens, Joel A; Baltes, Nicolas J; Duncan, Shona M; Farrell, Roberta L

    2010-07-01

    The historic expedition huts located in the Ross Sea Region of the Antarctic and the thousands of artifacts left behind by the early explorers represent important cultural heritage from the "Heroic Era" of Polar exploration. The hut at Cape Royds built by Ernest Shackleton and members of the 1907-1908 British Antarctic Expedition has survived the extreme Antarctic environment for over 100 years, but recent studies have shown many forms of deterioration are causing serious problems, and microbial degradation is evident in the historic wood. Conservation work to reduce moisture at the hut required removal of fodder, wood, and many different types of organic materials from the stables area on the north side of the structure allowing large numbers of samples to be obtained for these investigations. In addition, wood from historic food storage boxes exposed in a ravine adjacent to the hut were also sampled. Fungi were cultured on several different media, and pure cultures were obtained and identified by sequencing of the internal transcribed spacer region of rDNA. From the 69 cultures of filamentous fungi obtained, the most predominant genera were Cadophora (44%) followed by Thielavia (17%) and Geomyces (15%). Other fungi found included Cladosporium, Chaetomium, and isolates identified as being in Pezizomycotina, Onygenales, Nectriaceae, and others. No filamentous basidiomycetes were found. Phylogenetic analyses of the Cadophora species showed great species diversity present revealing Cadophora malorum, Cadophora luteo-olivacea, Cadophora fastigiata, as well as Cadophora sp. 4E71-1, a C. malorum-like species, and Cadophora sp. 7R16-1, a C. fastigiata-like species. Scanning electron microscopy showed extensive decay was present in the wood samples with type 1 and type 2 forms of soft rot evident in pine and birch wood, respectively. Fungi causing decay in the historic wooden structures and artifacts are of great concern, and this investigation provides insight into the

  19. Araneofauna captured in the forest and adjacent area, in the north of Paraná, Brazil Araneofauna capturada na mata e área aberta adjacente, no norte do Paraná, Brasil

    Lizandra Lucy Catelli

    2008-10-01

    Full Text Available Arachnids make up an exclusive predator group. Eating habit makes the arthropods to move around in search for hunting or building traps with silk threads. In order to know the araneofauna of the Godoy’s Forest State Park, pitfall-like traps were installed inside the forest, edge and adjacent area predominantly grassy. Collections were carried out fortnightly, in the period of a year, separating what was collected during the day and during the night. One hundred and twenty-one individuals were collected, belonging to 18 families where Lycosidae and Theridiidae were the most abundant, although Lyniphiidae family has prevailed in the forest area. Young individuals prevailed. It is concluded that the highest frequency and abundance of young individuals may be directly related to its dispersal and spiders belonging to the Lycosidae, Zoridae and Theridiidae families, being able to be used as bioindicators. Os aracnídeos compõem um grupo exclusivamente predador. O hábito alimentar faz com que o artropoda locomova-se em busca da caça ou construa armadilhas com fios de seda. Buscando conhecer a araneofauna do Parque Estadual Mata dos Godoy, foram instaladas armadilhas tipo ptiffal dentro da mata, borda e área adjacente, com vegetação predominantemente formada por gramíneas. As coletas eram realizadas quinzenalmente, no período de um ano, separando o coletado em diurno e noturno. Foram coletados 121 indivíduos, pertencentes a 18 famílias, das quais as famílias Lycosidae e Theridiidae foram as mais abundantes, embora a família Lyniphiidae tenha predominado na área de mata. Houve maior freqüência de indivíduos jovens. Conclui-se que a maior freqüência e abundância de indivíduos jovens pode estar diretamente relacionada a sua dispersão e, além disso, as aranhas pertencentes as famílias Lycosidae, Zoridae e Theridiidae, podem ser utilizadas como bioindicadores.

  20. Analysis of chemical compositions of individual atmospheric aerosol collected in Arctic and Antarctic area%南北极大气气溶胶单颗粒成分特点研究

    耿红; 李屹; 张志敏; 卢铁彦

    2012-01-01

    A quantitative single particle analytical technique, low-Z particle electron probe X-ray microanalysis (EPMA) was used to characterize 2821 individual particles in 16 sets of aerosol samples collected on July 25-31, 2007 at Ny-Alesund, Svalbard (78*551^1, 11?6'E) and 1460 individual particles in 5 sets of aerosol samples collected on March 12-16, 2009 at King George Island (62'13'S, 5%癢). There was great difference in chemical compositions between the atmospheric particles of the two sites. For the Arctic samples, aged sea salt, fresh (or genuine) sea salt, and mineral dust particles accounted for 44%, 9%, and 27%, respectively, in the examined particles (their aerodynamic diameters were in the range of 0.5~8um). Whereas for the Antarctic samples, fresh sea salt particles accounted for 74% and aged sea salt particles containing sulfate accounted for 19% in the examined particles (their aerodynamic diameters were in the range of 1-1 Oum). The majority of aged sea salt particles at Ny-Alesund contained nitrate, indicating that the atmosphere was disturbed by anthropogenic air pollutants. On the contrary, all of the aged sea salt particles contained sulfate in the samples at King George Island, none of them containing nitrate. It was likely that the oxidation of dimethylsulfide (DMS) emitted from phytoplanktons in the ocean rather than anthropogenic sulfur emission was responsible for the formation of sulfate-containing aged sea salt particles, implying that the air in the Antarctic area was relatively clean, without being polluted by anthropogenic pollutants.%运用定量电子探针微区分析技术(EPMA)分别测定了采自北极新奥尔松地区(78+55'N、11*56'E)和南极乔治王岛(62*3'S、58*47'W)极昼天气下PM10大气颗粒物样品.结果表明,北极和南极大气颗粒物化学成分存在很大差异,表现出各自不同的特点.北极的颗粒类型中,“反应的海盐”和“矿物尘”分别占颗粒总数的44%和27%,“新鲜

  1. 33 CFR 151.32 - Special areas for the purpose of Annex II.

    2010-07-01

    ... Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Noxious Liquid Substance Pollution..., the special areas are the Baltic Sea area, the Black Sea area, and the Antarctic area which are... in the Antarctic area. (b) In accordance with paragraph (13)(a) of Regulation 5 of Annex II of...

  2. Did the continent and sea have different temperatures in the northern Antarctic Peninsula during the Middle Eocene?

    A.L. Cione

    2007-12-01

    Full Text Available The Seymour Island beds include a remarkable representation of the continental flora and fauna and marine fauna of Eocene in southern high latitudes. We suggest that, at least during the deposition of the best sampled unit, the Cucullaea I Allomember of the La Meseta Alloformation in the Seymour Island area, a cold temperate terrestrial environment co-existed with relatively warmer temperatures in the adjacent shallow shelf sea. This is suggested by the fish and invertebrate fauna and could have been due to the presence of warmer waters of a current reaching the region from the north. The temperature drop proposed for the time of deposition of the uppermost part of the La Meseta Formation (Submeseta Allomember appears to correspond to the global drop of the end of the Eocene and beginning of Oligocene and not to the establishment of the Antarctic Circumpolar Current.

  3. DIVERSITY OF NEKTON IN DONGSHAN BAY AND ADJACENT AREAS%东山湾及其邻近海域游泳动物多样性的分析

    林龙山; 赵贵根; 李渊; 高天翔; 张静

    2012-01-01

    根据2009年11月至2010年8月在东山湾及其邻近海域的调查资料,统计渔获物物种组成,计算该海域各物种的相对重要性指数(IRI)、相对资源密度、Margalef种类丰富度指数、Shannon-Weiner种类多样性指数以及Pielou均匀度指数,并分析其时空分布特征.结果表明,东山湾及其邻近海域的物种组成比例与台湾海峡大体一致.秋冬春夏4个季度优势种种类数均较少,分别为4、2、1、3种,且季节更替明显.不同季节多样性指数表现为夏季>春季>秋季>冬季,各季Margalef种类丰富度均值为3.54,Shannon-Weiner种类多样性均值为1.99,Pielou均匀度均值为0.71; 各调查站位Margalef种类丰富度均值为7.87,Shannon-Weiner种类多样性均值为2.94,Pielou均匀度均值为0.75,表明该海域生物多样性处于较低水平.分析东山湾及其邻近海域游泳动物多样性,可为今后开展海洋工程建设渔业资源损益评价、生态环境修复工作和基于生态系统的渔业和海洋管理策略提供科学依据.%The analyses of diversity of nekton in Dongshan Bay and adjacent areas were carried out based on the data of bottom surveys from November 2009 to August 2010. A systematic analysis of the nekton species composition was studied, and the index of relative importance (IRI), relative resource density, Margalef richness index, Shannon-Weiner diversity index and Pielou evenness index were employed to assess the diversity of nekton. Also the spatial-temporal pattern of the nekton species in this area was described. The results showed that there were a total of 168 species involving 20 orders, 74 families and 109 genera in Dongshan Bay and adjacent areas. There were 114 fish species which was the largest category, accounting for 67.86%, and the results were shown the same trend compared with that of Taiwan Strait. In term of seasonal distribution, the most abundant of species was in spring (95) and least in autumn (66); in term of

  4. Geochemistry and geochronology of the Late Permian mafic intrusions along the boundary area of Jiamusi and Songnen-Zhangguangcai Range massifs and adjacent regions, northeastern China: Petrogenesis and implications for the tectonic evolution of the Mudanjiang Ocean

    Dong, Yu; Ge, Wen-chun; Yang, Hao; Xu, Wen-liang; Bi, Jun-hui; Wang, Zhi-hui

    2017-01-01

    This paper presents zircon U-Pb ages, whole-rock major and trace element data, and Hf isotope data for the metagabbros from the Zhushan pluton and gabbros from the Taiping pluton along the boundary area of Jiamusi and Songnen-Zhangguangcai Range massifs and adjacent regions, which will not only place important constraints on the rock-forming ages, source characteristics and tectonic setting of these gabbros, but will also provide insights into understanding the Permian tectonic evolution between the Jiamusi Massif and the Songnen-Zhangguangcai Range Massif. Zircon U-Pb dating, determined using laser ablation-inductively coupled plasma-mass spectrometry and secondary-ion mass spectrometry, indicates that the magmatic zircons from the Zhushan and Taiping plutons yield 206Pb/238U ages of 256 ± 2 Ma and 259 ± 3 Ma, respectively, interpreted as the emplacement ages of the intrusions. The metagabbros from the Zhushan pluton display the geochemical characteristics of calc-alkaline series rocks, and are enriched in light rare earth and large ion lithophile elements, and depleted in Nb, Ta, P, Zr and Hf. The εHf(t) values of magmatic zircons in these metagabbros vary from - 5.47 to + 0.74. All these geochemical features indicate that the primary magma of the Zhushan pluton was derived from an enriched lithospheric mantle source that was metasomatized by subducted slab-derived fluids. The gabbros from the Taiping pluton are also enriched in large ion lithophile elements (e.g., Rb, Ba and U) relative to high field strength elements, and have negative Nb-Ta-P anomalies, with εHf(t) values of - 4.02 to - 1.70. It is inferred that they also formed from a primary magma generated by the partial melting of enriched lithospheric mantle that was metasomatized by subducted slab-derived fluids. The rocks from the Zhushan and Taiping plutons have similar petrogenetic processes, but their primary magmas are likely to be derived from two distinct magma sources based on geochemical and

  5. Study on real-time prediction of oil spill in Changjiang River Estuary and its adjacent sea areas%长江口及邻近海域溢油实时预测研究

    潘冲; 王惠群; 管卫兵; 杨扬

    2011-01-01

    Changjiang River Estuary is located in the most important economic zone in China, where busy shipping, extensive petrochemical industry as well as more and more ocean engineering result in significantly increasing risks of oil spill pollution. In this study, we have established a three-dimensional unstructured triangular grid hydrodynamic model coupling wind current, tidal current and baroclinic current for Changjiang River Estuary and its adjacent sea areas based on the SELFE (Semi-implicit Eulerian-Lagrangian Finite Element) model, which is the newly developed finite element model in the world with high numerical accuracy, computational efficiency and stability. Verifications of the model results against historical and field data prove that the hydrodynamic model can reflected the hydrodynamic features of the study area well. Based on the hydrodynamic model and the theory of Eulerian-Lagrangian method and random walk, a three-dimensional particle diffusion model considering evaporation processes and wave effects has been developed for the spilled oil slick. Combined with the real-time forecast of wind field and corresponding wave data, the whole model system is suitable for predicting unexpected oil spilling in study area. The model was verified with simulated oil spill with the observations of surface drift floats, which showed good numerical behavior of the model. Two numerical experiments were carried out to understand the responses of the spilled oil to the wind and to inspect the applicability of the whole oil spill prediction system for Changjiang River Estuary and its adjacent waters. In the experiments, southeast wind and northwest wind were used to represent the typical winds of summer and winter, respectively. The results show that at the position outside the deep channel, the spilled oil slick drifts spirally toward southeast under the influence of tidal fluctuation, northwest wind and the Changjiang diluted water, while it drifts spirally northward

  6. Levoglucosan and phenols in Antarctic marine, coastal and plateau aerosols.

    Zangrando, Roberta; Barbaro, Elena; Vecchiato, Marco; Kehrwald, Natalie M; Barbante, Carlo; Gambaro, Andrea

    2016-02-15

    Due to its isolated location, Antarctica is a natural laboratory for studying atmospheric aerosols and pollution in remote areas. Here, we determined levoglucosan and phenolic compounds (PCs) at diverse Antarctic sites: on the plateau, a coastal station and during an oceanographic cruise. Levoglucosan and PCs reached the Antarctic plateau where they were observed in accumulation mode aerosols (with median levoglucosan concentrations of 6.4 pg m(-3) and 4.1 pg m(-3), and median PC concentrations of 15.0 pg m(-3) and 7.3 pg m(-3)). Aged aerosols arrived at the coastal site through katabatic circulation with the majority of the levoglucosan mass distributed on larger particulates (24.8 pg m(-3)), while PCs were present in fine particles (34.0 pg m(-3)). The low levoglucosan/PC ratios in Antarctic aerosols suggest that biomass burning aerosols only had regional, rather than local, sources. General acid/aldehyde ratios were lower at the coastal site than on the plateau. Levoglucosan and PCs determined during the oceanographic cruise were 37.6 pg m(-3) and 58.5 pg m(-3) respectively. Unlike levoglucosan, which can only be produced by biomass burning, PCs have both biomass burning and other sources. Our comparisons of these two types of compounds across a range of Antarctic marine, coastal, and plateau sites demonstrate that local marine sources dominate Antarctic PC concentrations.

  7. Stable water isotopes of precipitation and firn cores from the northern Antarctic Peninsula region as a proxy for climate reconstruction

    F. Fernandoy

    2012-03-01

    Full Text Available In order to investigate the climate variability in the northern Antarctic Peninsula region, this paper focuses on the relationship between stable isotope content of precipitation and firn, and main meteorological variables (air temperature, relative humidity, sea surface temperature, and sea ice extent. Between 2008 and 2010, we collected precipitation samples and retrieved firn cores from several key sites in this region. We conclude that the deuterium excess oscillation represents a robust indicator of the meteorological variability on a seasonal to sub-seasonal scale. Low absolute deuterium excess values and the synchronous variation of both deuterium excess and air temperature imply that the evaporation of moisture occurs in the adjacent Southern Ocean. The δ18O-air temperature relationship is complicated and significant only at a (multiseasonal scale. Backward trajectory calculations show that air-parcels arriving at the region during precipitation events predominantly originate at the South Pacific Ocean and Bellingshausen Sea. These investigations will be used as a calibration for ongoing and future research in the area, suggesting that appropriate locations for future ice core research are located above 600 m a.s.l. We selected the Plateau Laclavere, Antarctic Peninsula as the most promising site for a deeper drilling campaign.

  8. Automatic focusing system of BSST in Antarctic

    Tang, Peng-Yi; Liu, Jia-Jing; Zhang, Guang-yu; Wang, Jian

    2015-10-01

    Automatic focusing (AF) technology plays an important role in modern astronomical telescopes. Based on the focusing requirement of BSST (Bright Star Survey Telescope) in Antarctic, an AF system is set up. In this design, functions in OpenCV is used to find stars, the algorithm of area, HFD or FWHM are used to degree the focus metric by choosing. Curve fitting method is used to find focus position as the method of camera moving. All these design are suitable for unattended small telescope.

  9. 33 CFR 151.13 - Special areas for Annex I of MARPOL 73/78.

    2010-07-01

    ... Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Oil Pollution § 151.13 Special... area, the Gulf of Aden, and the Antarctic area, the North West European waters, and Oman area of the... Sea, Baltic Sea, Black Sea, and the Antarctic area. (b) Subject to the provisions of § 151.11— (1)...

  10. 77 FR 50720 - Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978

    2012-08-22

    ... 1978 (Pub. L. 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has... whales in the penguin's foraging area within the leads of the McMurdo Sound fast ice as it breaks up....

  11. Environmental contamination in Antarctic ecosystems.

    Bargagli, R

    2008-08-01

    Although the remote continent of Antarctica is perceived as the symbol of the last great wilderness, the human presence in the Southern Ocean and the continent began in the early 1900s for hunting, fishing and exploration, and many invasive plant and animal species have been deliberately introduced in several sub-Antarctic islands. Over the last 50 years, the development of research and tourism have locally affected terrestrial and marine coastal ecosystems through fuel combustion (for transportation and energy production), accidental oil spills, waste incineration and sewage. Although natural "barriers" such as oceanic and atmospheric circulation protect Antarctica from lower latitude water and air masses, available data on concentrations of metals, pesticides and other persistent pollutants in air, snow, mosses, lichens and marine organisms show that most persistent contaminants in the Antarctic environment are transported from other continents in the Southern Hemisphere. At present, levels of most contaminants in Antarctic organisms are lower than those in related species from other remote regions, except for the natural accumulation of Cd and Hg in several marine organisms and especially in albatrosses and petrels. The concentrations of organic pollutants in the eggs of an opportunistic top predator such as the south polar skua are close to those that may cause adverse health effects. Population growth and industrial development in several countries of the Southern Hemisphere are changing the global pattern of persistent anthropogenic contaminants and new classes of chemicals have already been detected in the Antarctic environment. Although the Protocol on Environmental Protection to the Antarctic Treaty provides strict guidelines for the protection of the Antarctic environment and establishes obligations for all human activity in the continent and the Southern Ocean, global warming, population growth and industrial development in countries of the Southern

  12. Moessbauer study of thermal metamorphosed Antarctic meteorites

    Scorzelli, R.B. (Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, RJ (Brazil)); Galvao da Silva, E. (Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, RJ (Brazil) Dept. de Fisica, Univ. Federal de Minas Gerais, Belo Horizonte (Brazil)); Souza Azevedo, I. (Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, RJ (Brazil))

    1994-02-01

    In this paper we report on variable temperature Moessbauer spectroscopy measurements on Yamato-82162 and Yamato-86720. These Antarctic carbonaceous chondrites contrast with other non-Antarctic carbonaceous chondrites in which no evidences of thermal metamorphism have been found. (orig.)

  13. Spatial-temporal characters of Antarctic sea ice variation

    Ma Lijuan; Lu Longhua; Bian Lingen

    2004-01-01

    Using sea ice concentration dataset covering the period of 1968-2002 obtained from the Hadley Center of UK, this paper investigates characters of Antarctic sea ice variations .The finding demonstrates that the change of mean sea-ice extent is almost consistent with that of sea-ice area, so sea-ice extent can be chosen to go on this research. The maximum and the minimum of Antarctic sea ice appear in September and February respectively. The maximum and the maximal variation of sea ice appear in Weddell Sea and Ross Sea, while the minimum and the minimal variation of sea-ice appear in Antarctic Peninsula. In recent 35 years, as a whole, Antarctic sea ice decreased distinctly. Moreover, there are 5 subdivision characteristic regions considering their different variations. Hereinto, the sea-ice extent of Weddell Sea and Ross Sea regions extends and area increases, while the sea-ice extent of the other three regions contracts and area decreases. They are all of obvious 2-4 years and 5-7 years significant oscillation periods. It is of significance for further understanding the sea-ice-air interaction in Antarctica region and discussing the relationship between sea-ice variation and atmospheric circulation.

  14. 长江口外海域龙头鱼营养生态学特征%Feeding ecology of Harpadon nehereus in areas adjacent to Changjiang River estuary

    潘绪伟; 程家骅

    2011-01-01

    Harpadon nehereus, a benthic dwelling fish distributing throughout the Indian Ocean and Western Pacific, plays an important role in marine ecosystems. Despite its abundance and importance to fisheries, little is known about the biology of this species. We evaluated ontogenetic and diet variation in the feeding ecology of H. Nehereus in the areas adjacent to the Changjiang River Estuary. We collected a total of 450 individuals ranging in size from 64-280 mm standard length (SL) during monthly surveys in the south Yellow Sea and the north East China Sea between September 2009 and August 2010. Based on stomach content analysis, H. Nehereus was a gen-eralist. We identified 39 prey species, of which other fish were the most abundant, accounting for 84.13% of the total food by weight. At the species level, the primary prey were H. Nehereus, Pseudosciaena polyactis, Apo-gonichthys lineatus, Johnius belengerii, and Oratosquilla oratorio. The feeding intensity, as indicated by the percentage of empty stomachs and the mean stomach fullness index, varied significantly among seasons. Feeding activity was the highest in autumn and lowest in winter. There were significant seasonal differences in the diet of H. Nehereus. Decapods were more important in spring, whereas fish were more important during other seasons. Both the feeding intensity and diet composition varied significantly among different size classes. There were two abrupt changes in diet composition at about 100 and 230 mm SL, the latter characterized by a switch from eury-phagy to stenophagy. The trophic level of Harpadon nehereus was 3.80, suggesting that this species was a high level predator within the food web in the Yellow Sea and East China Sea.%利用2009年9月至2010年8月在东海北部、黄海南部海域获取的龙头鱼(Harpadon nehereus)样品,采用胃含物分析法,对龙头鱼的摄食习性进行了研究.结果表明,龙头鱼摄食饵料种类有39种,鱼类是其主要饵料类

  15. 青藏高原及其周缘地区各向异性研究进展%Reviews on the anisotropy studies in the Tibetan Plateau and its adjacent areas

    黄星; 高原

    2014-01-01

    Tibetan Plateau is known as the roof of the world.It is a young conti-nental-continental collisional orogenic belt.The Indian Plate and Eurasian Plate collide there together.It is of significance for us to reveal the deep characteris-tics of each block in the Tibetan Plateau and to understand the interior mecha-nism of continental deformation.This paper briefly described the current four mainstream kinetic models of Tibetan Plateau,i.e.,subduction model,collision model,extrusion model,and delamination-slab breakoff model.Followed by an overview of the research progress of anisotropy in the Tibetan Plateau and its adjacent areas,this paper discussed the future trend of anisotropy studies.Sev-eral issues need to be paid attention to in anisotropy studies:① a variety of sources resulting in anisotropy;② relationship between anisotropy and deep structure;③ application of the surface wave.In order to better explain the ani-sotropy,we have to understand the relationship between deep structure and ani-sotropy,finding more sophisticated research tools.For now,the surface wave and body wave inversion can be combined to better constrain the anisotropic res-olution.Geodynamics simulation and seismic anisotropy may also be combined as one of the future trend.%首先简要介绍了青藏高原目前主流的4种动力学模型,即俯冲模型、碰撞模型、挤出模型和拆沉-板片断离模型。然后概述了青藏高原及其周缘地区各向异性的研究进展,展望各向异性研究的方向,并着重探讨了各向异性研究中需要重视的几个问题:①各向异性的多种来源;②各向异性与深部结构的关系;③面波等新方法的应用。为了更好地定量解释各向异性,需要了解深部结构与各向异性之间的关系,发展更加精细的研究手段。就目前来看,面波与体波的联合反演可以更好地约束各向异性的分辨率,而将地球动力学模拟等正演手段与地震波各

  16. Regulating Antarctic Tourism and the Precautionary Principle

    Bastmeijer, C.J.; Roura, R.

    2004-01-01

    On the basis of an overview of the developments in Antarctic tourism since 1956, this current development note examines the issue of international regulation of Antarctic tourism. After discussing one of the main management issues in respect of Antarctic tourism ¿ the assessment and prevention of cu

  17. Longitudinal surface structures (flowstripes on Antarctic glaciers

    N. F. Glasser

    2011-11-01

    Full Text Available Longitudinal surface structures (''flowstripes'' are common on many glaciers but their origin and significance are poorly understood. In this paper we present observations of the development of these longitudinal structures from four different Antarctic glacier systems (the Lambert Glacier/Amery Ice Shelf area, outlet glaciers in the Ross Sea sector, ice-shelf tributary glaciers on the Antarctic Peninsula, and the onset zone of a tributary to the Recovery Glacier Ice Stream in the Filchner Ice Shelf area. Mapping from optical satellite images demonstrates that longitudinal surface structures develop in two main situations: (1 as relatively wide flow stripes within glacier flow units and (2 as relatively narrow flow stripes where there is convergent flow around nunataks or at glacier confluence zones. Our observations indicate that the confluence features are narrower, sharper, and more clearly defined features. They are characterised by linear troughs or depressions on the ice surface and are much more common than the former type. Longitudinal surface structures within glacier flow units have previously been explained as the surface expression of localised bed perturbations but a universal explanation for those forming at glacier confluences is lacking. Here we propose that these features are formed at zones of ice acceleration and extensional flow at glacier confluences. We provide a schematic model for the development of longitudinal surface structures based on extensional flow that can explain their ridge and trough morphology as well as their down-ice persistence.

  18. Antarctic Porifera database from the Spanish benthic expeditions

    Pilar Rios

    2014-04-01

    Full Text Available The information about the sponges in this dataset is derived from the samples collected during five Spanish Antarctic expeditions: Bentart 94, Bentart 95, Gebrap 96, Ciemar 99/00 and Bentart 2003. Samples were collected in the Antarctic Peninsula and Bellingshausen Sea at depths ranging from 4 to 2044 m using va­rious sampling gears.The Antarctic Porifera database from the Spanish benthic expeditions is unique as it provides in­formation for an under-explored region of the Southern Ocean (Bellingshausen Sea. It fills an information gap on Antarctic deep-sea sponges, for which there were previously very few data.This phylum is an important part of the Antarctic biota and plays a key role in the structure of the Antarctic marine benthic community due to its considerable diversity and predominance in different areas. It is often a dominant component of Southern Ocean benthic communities.The quality of the data was controlled very thoroughly with GPS systems onboard the R/V Hesperides and by checking the data against the World Porifera Database (which is part of the World Register of Marine Species, WoRMS. The data are therefore fit for completing checklists, inclusion in biodivers­ity pattern analysis and niche modelling. The authors can be contacted if any additional information is needed before carrying out detailed biodiversity or biogeographic studies.The dataset currently contains 767 occurrence data items that have been checked for systematic reliability. This database is not yet complete and the collection is growing. Specimens are stored in the author’s collection at the Spanish Institute of Oceanography (IEO in the city of Gijón (Spain. The data are available in GBIF.

  19. Emerging spatial patterns in Antarctic prokaryotes

    Chun Wie eChong

    2015-09-01

    Full Text Available Recent advances in knowledge of patterns of biogeography in terrestrial eukaryotic organisms have led to a fundamental paradigm shift in understanding of the controls and history of life on land in Antarctica, and its interactions over the long term with the glaciological and geological processes that have shaped the continent. However, while it has long been recognized that the terrestrial ecosystems of Antarctica are dominated by microbes and their processes, knowledge of microbial diversity and distributions has lagged far behind that of the macroscopic eukaryote organisms. Increasing human contact with and activity in the continent is leading to risks of biological contamination and change in a region whose isolation has protected it for millions of years at least; these risks may be particularly acute for microbial communities which have, as yet, received scant recognition and attention. Even a matter apparently as straightforward as Protected Area designation in Antarctica requires robust biodiversity data which, in most parts of the continent, remain almost completely unavailable. A range of important contributing factors mean that it is now timely to reconsider the state of knowledge of Antarctic terrestrial prokaryotes. Rapid advances in molecular biological approaches are increasingly demonstrating that bacterial diversity in Antarctica may be far greater than previously thought, and that there is overlap in the environmental controls affecting both Antarctic prokaryotic and eukaryotic communities. Bacterial dispersal mechanisms and colonization patterns remain largely unaddressed, although evidence for regional evolutionary differentiation is rapidly accruing and, with this, there is increasing appreciation of patterns in regional bacterial biogeography in this large part of the globe. In this review, we set out to describe the state of knowledge of Antarctic prokaryote diversity patterns, drawing analogy with those of eukaryote

  20. Ocean processes at the Antarctic continental slope.

    Heywood, Karen J; Schmidtko, Sunke; Heuzé, Céline; Kaiser, Jan; Jickells, Timothy D; Queste, Bastien Y; Stevens, David P; Wadley, Martin; Thompson, Andrew F; Fielding, Sophie; Guihen, Damien; Creed, Elizabeth; Ridley, Jeff K; Smith, Walker

    2014-07-13

    The Antarctic continental shelves and slopes occupy relatively small areas, but, nevertheless, are important for global climate, biogeochemical cycling and ecosystem functioning. Processes of water mass transformation through sea ice formation/melting and ocean-atmosphere interaction are key to the formation of deep and bottom waters as well as determining the heat flux beneath ice shelves. Climate models, however, struggle to capture these physical processes and are unable to reproduce water mass properties of the region. Dynamics at the continental slope are key for correctly modelling climate, yet their small spatial scale presents challenges both for ocean modelling and for observational studies. Cross-slope exchange processes are also vital for the flux of nutrients such as iron from the continental shelf into the mixed layer of the Southern Ocean. An iron-cycling model embedded in an eddy-permitting ocean model reveals the importance of sedimentary iron in fertilizing parts of the Southern Ocean. Ocean gliders play a key role in improving our ability to observe and understand these small-scale processes at the continental shelf break. The Gliders: Excellent New Tools for Observing the Ocean (GENTOO) project deployed three Seagliders for up to two months in early 2012 to sample the water to the east of the Antarctic Peninsula in unprecedented temporal and spatial detail. The glider data resolve small-scale exchange processes across the shelf-break front (the Antarctic Slope Front) and the front's biogeochemical signature. GENTOO demonstrated the capability of ocean gliders to play a key role in a future multi-disciplinary Southern Ocean observing system.

  1. 78 FR 66384 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    2013-11-05

    ... the Antarctic Conservation Act of 1978 (Pub. L. 95-541), as amended by the Antarctic Science, Tourism... Specially Protected Areas. Application Details Permit Application: 2014-024 1. Applicant: Ron Naveen... authorized under ACA 2014- 001 (previously issued to Ron Naveen). The recorders would be installed 3-5...

  2. Arctic and Antarctic Sea Ice Changes and Impacts (Invited)

    Nghiem, S. V.

    2013-12-01

    The extent of springtime Arctic perennial sea ice, important to preconditioning summer melt and to polar sunrise photochemistry, continues its precipitous reduction in the last decade marked by a record low in 2012, as the Bromine, Ozone, and Mercury Experiment (BROMEX) was conducted around Barrow, Alaska, to investigate impacts of sea ice reduction on photochemical processes, transport, and distribution in the polar environment. In spring 2013, there was further loss of perennial sea ice, as it was not observed in the ocean region adjacent to the Alaskan north coast, where there was a stretch of perennial sea ice in 2012 in the Beaufort Sea and Chukchi Sea. In contrast to the rapid and extensive loss of sea ice in the Arctic, Antarctic sea ice has a trend of a slight increase in the past three decades. Given the significant variability in time and in space together with uncertainties in satellite observations, the increasing trend of Antarctic sea ice may arguably be considered as having a low confidence level; however, there was no overall reduction of Antarctic sea ice extent anywhere close to the decreasing rate of Arctic sea ice. There exist publications presenting various factors driving changes in Arctic and Antarctic sea ice. After a short review of these published factors, new observations and atmospheric, oceanic, hydrological, and geological mechanisms contributed to different behaviors of sea ice changes in the Arctic and Antarctic are presented. The contribution from of hydrologic factors may provide a linkage to and enhance thermal impacts from lower latitudes. While geological factors may affect the sensitivity of sea ice response to climate change, these factors can serve as the long-term memory in the system that should be exploited to improve future projections or predictions of sea ice changes. Furthermore, similarities and differences in chemical impacts of Arctic and Antarctic sea ice changes are discussed. Understanding sea ice changes and

  3. Fish species diversity and conservation in Beijing and adjacent areas%北京及其邻近地区野生鱼类物种多样性及其资源保育

    张春光; 赵亚辉; 邢迎春; 郭瑞禄; 张清; 冯云; 樊恩源

    2011-01-01

    作者2002-2010年间,连续多年对北京及周边地区的野生鱼类进行了实地调查和采集,结合对中国科学院动物研究所国家动物博物馆馆藏鱼类标本及相关文献资料的整理,得出北京及其邻近地区分布过的鱼类计有93种,隶属于13目23科73属;去除引入种,自然分布于该地区的原生野生鱼类为85种(包括经通海河流上溯至区域内的河口咸淡水、洄游性及原产但现为引入的物种),隶属于12目21科65属.目前,区域内自然—半自然水体中可以见到的野生鱼类计有49种(包括引入种6种),原生的野生鱼类为43种,隶属于6目12科36属.与历史记录相比,从目到种各分类阶元的消失率均超过40%,特别是原生野生鱼类的消失率更接近50%;伴随着大量土著鱼类的消失,物种组成的异质性明显降低,物种多样性下降的程度十分明显.自然环境持续干旱、兴修水利、城市建成区面积迅速扩张和人口膨胀等引起的水域面积减小、原有水域环境的改变、过度捕捞等应是引起土著鱼类物种多样性急剧下降的主要原因.为了能使原有土著鱼类资源尽快得到更有效的保护和恢复,建议进一步做好鱼类资源本底调查、进一步加强渔政管理包括对现有水生生物保护区的管理、筹建新的水生生物保护区、建立种质资源库、订立地方性水生野生动物保护名录、加强对水生野生动物保护的宣传教育、严控引入鱼种等.%Based on field surveys between 2002 and 2010, and fish collections in the National Zoological Museum, Institute of Zoology, Chinese Academy of Sciences, a total of 93 wild fish species including 12 introduced species had been recorded in Beijing and adjacent areas. Eighty five of these species, including some migratory and estuarine fishes, are native to the region. Only 43 native wild species were collected in our field work from 2002 to 2010. Compared with the historical

  4. Paleo-fluid characteristics and preservation of hydrocarbons in the Sangzhi-Shimen synclinorium and adjacent areas%桑植-石门复向斜及邻区古流体特征与油气保存意义

    刘安; 危凯; 李旭兵; 王保忠; 王强

    2015-01-01

    通过对桑植—石门复向斜及相邻地区震旦系—三叠系方解石脉和围岩的碳氧同位素、锶同位素对比,结合方解石脉中流体包裹体测试分析,研究了桑植—石门地区古流体特征及其油气保存意义。下古生界围岩87 Sr/86 Sr部分高于同期海水,也高于方解石脉,表明围岩在裂隙形成之前受到高87 Sr/86 Sr流体改造。桑植—石门复向斜北翼温泉附近的方解石脉体具高87 Sr/86 Sr、低δ13 C、低δ18 O特征,显示大气水参与了方解石脉沉淀,逆断层可能在形成之初就不具封闭性。流体包裹体盐度和均一温度指示,桑植—石门地区上寒武统娄山关组上覆盖层残余厚度小于3 km,不具封闭能力;中寒武统孔王溪组方解石脉流体包裹体高盐度表明膏盐盖层在研究区广泛分布,在埋深超过2 km条件下对下伏地层具有较好的封盖能力。桑植—石门复向斜田二垭、向家垭、车坊背斜圈闭、桥头、中坪隐伏圈闭保存条件较好,除田二垭背斜外,可以同时将震旦系灯影组、寒武系清虚洞组白云岩作为勘探目的层。%The paleo⁃fluid characteristics and hydrocarbon preservation in the Sangzhi-Shimen synclinorium and adjacent areas are discussed using comparisons of C, O, and Sr isotopes between the calcite veins and surrounding rocks in the Sinian and Triassic formations and combined with the tests of fluid inclusions in calcite veins. The 87Sr/ 86Sr values of surrounding rocks in the Lower Paleozoic are higher than those of contemporary seawater and calcite veins, which suggests that the surrounding rocks had been reformed by fluid with high 87 Sr/ 86 Sr values before fracturing. The calcite veins close to thermal springs in the north of Sangzhi-Shimen synclinorium have high 87 Sr/ 86 Sr values, low δ13 C and low δ18 O values, which can be explained by the mixing of meteoric water during calcite vein deposition and suggests

  5. Mass Balance of the Northern Antarctic Peninsula and its Ongoing Response to Ice Shelf Loss

    Scambos, T. A.; Berthier, E.; Haran, T. M.; Shuman, C. A.; Cook, A. J.; Bohlander, J. A.

    2012-12-01

    An assessment of the most rapidly changing areas of the Antarctic Peninsula (north of 66°S) shows that ice mass loss for the region is dominated by areas affected by eastern-Peninsula ice shelf losses in the past 20 years. Little if any of the mass loss is compensated by increased snowfall in the northwestern or far northern areas. We combined satellite stereo-image DEM differencing and ICESat-derived along-track elevation changes to measure ice mass loss for the Antarctic Peninsula north of 66°S between 2001-2010, focusing on the ICESat-1 period of operation (2003-2009). This mapping includes all ice drainages affected by recent ice shelf loss in the northeastern Peninsula (Prince Gustav, Larsen Inlet, Larsen A, and Larsen B) as well as James Ross Island, Vega Island, Anvers Island, Brabant Island and the adjacent west-flowing glaciers. Polaris Glacier (feeding the Larsen Inlet, which collapsed in 1986) is an exception, and may have stabilized. Our method uses ASTER and SPOT-5 stereo-image DEMs to determine dh/dt for elevations below 800 m; at higher elevations ICESat along-track elevation differencing is used. To adjust along-track path offsets between its 2003-2009 campaigns, we use a recent DEM of the Peninsula to establish and correct for cross-track slope (Cook et al., 2012, doi:10.5194/essdd-5-365-2012; http://nsidc.org/data/nsidc-0516.html) . We reduce the effect of possible seasonal variations in elevation by using only integer-year repeats of the ICESat tracks for comparison. Mass losses are dominated by the major glaciers that had flowed into the Prince Gustav (Boydell, Sjorgren, Röhss), Larsen A (Edgeworth, Bombardier, Dinsmoor, Drygalski), and Larsen B (Hektoria, Jorum, and Crane) embayments. The pattern of mass loss emphasizes the significant and multi-decadal response to ice shelf loss. Areas with shelf losses occurring 30 to 100s of years ago seem to be relatively stable or losing mass only slowly (western glaciers, northernmost areas). The

  6. Special Stamps:Antarctic Scenery

    2002-01-01

    In July 2002, the State Postal Bureau issued a set of three stamps, whose theme is Antarctic scenery.The first stamp depicts an iceberg. Antarctica is where 90 percent of the world’s ice exists. Each year countless icebergs float majestically through the sea, and are a magnificent scenic feature of Antarctica.

  7. Principles of the Antarctic Treaty

    Candidi, M.

    The operation of any base or expedition to Antarctica is regulated by the mutual agreement among nations in the “Antarctic Treaty”. This treaty deals with the major aspects of life in Antarctica and its main principles and provisions are described in what follows.

  8. Evolution of the Antarctic Peninsula lithosphere: Evidence from Mesozoic mafic rocks

    Riley, T. R.; Curtis, M. L.; Flowerdew, M. J.; Whitehouse, M. J.

    2016-02-01

    New geochronology from a thick (> 800 m) basaltic succession along the eastern margin of the Antarctic Peninsula confirm a Middle Jurassic age (178 ± 1 Ma). This marginally postdates the adjacent Ferrar large igneous province of the Transantarctic Mountains and predates the extensive silicic volcanism of the Mapple Formation (~ 170 Ma) of the Antarctic Peninsula. The geochemistry of other rare, but broadly contemporaneous, basaltic successions of the Antarctic Peninsula, along with Cretaceous-age mafic dykes, are used to interpret the influences of lithospheric and asthenospheric mantle sources during the Mesozoic. Two significant high magmatic addition rate events occurred along the Antarctic Peninsula continental margin at 170 and 110 Ma and can be correlated to events along the South American Cordillera. These 'flare-up' events are characterised by extensive silicic (mostly ignimbrite) volcanism of the Chon Aike Province (V2 event: 170 Ma) and significant granitoid batholith emplacement of the Lassiter Coast intrusive suite (110 Ma). The 170 Ma event is exposed across large parts of the northern Antarctic Peninsula, whilst the 110 Ma event is more widespread across the southern Antarctic Peninsula. The basaltic volcanism described here precedes the 'flare-up' event at 170 Ma and has geochemical characteristics that indicate a thickened lithosphere prevailed. A major dyke swarm that followed the 170 Ma event indicates that extensive lithospheric thinning had occurred, which allowed the ascent of depleted mafic melts. The thinning was the direct result of widespread lower crustal/upper lithospheric melting associated with the silicic volcanism. In the southern Antarctic Peninsula, the lithosphere remained over thickened until the emplacement of the major batholiths of the Lassiter Coast intrusive suite at 110 Ma and was then immediately followed by the emplacement of more asthenosphere-like melts indicating extensive lithospheric thinning.

  9. A multivariate analysis of Antarctic sea ice since 1979

    Magalhaes Neto, Newton de; Evangelista, Heitor [Universidade do Estado do Rio de Janeiro (Uerj), LARAMG - Laboratorio de Radioecologia e Mudancas Globais, Maracana, Rio de Janeiro, RJ (Brazil); Tanizaki-Fonseca, Kenny [Universidade do Estado do Rio de Janeiro (Uerj), LARAMG - Laboratorio de Radioecologia e Mudancas Globais, Maracana, Rio de Janeiro, RJ (Brazil); Universidade Federal Fluminense (UFF), Dept. Analise Geoambiental, Inst. de Geociencias, Niteroi, RJ (Brazil); Penello Meirelles, Margareth Simoes [Universidade do Estado do Rio de Janeiro (UERJ)/Geomatica, Maracana, Rio de Janeiro, RJ (Brazil); Garcia, Carlos Eiras [Universidade Federal do Rio Grande (FURG), Laboratorio de Oceanografia Fisica, Rio Grande, RS (Brazil)

    2012-03-15

    Recent satellite observations have shown an increase in the total extent of Antarctic sea ice, during periods when the atmosphere and oceans tend to be warmer surrounding a significant part of the continent. Despite an increase in total sea ice, regional analyses depict negative trends in the Bellingshausen-Amundsen Sea and positive trends in the Ross Sea. Although several climate parameters are believed to drive the formation of Antarctic sea ice and the local atmosphere, a descriptive mechanism that could trigger such differences in trends are still unknown. In this study we employed a multivariate analysis in order to identify the response of the Antarctic sea ice with respect to commonly utilized climate forcings/parameters, as follows: (1) The global air surface temperature, (2) The global sea surface temperature, (3) The atmospheric CO{sub 2} concentration, (4) The South Annular Mode, (5) The Nino 3, (6) The Nino (3 + 4, 7) The Nino 4, (8) The Southern Oscillation Index, (9) The Multivariate ENSO Index, (10) the Total Solar Irradiance, (11) The maximum O{sub 3} depletion area, and (12) The minimum O{sub 3} concentration over Antarctica. Our results indicate that western Antarctic sea ice is simultaneously impacted by several parameters; and that the minimum, mean, and maximum sea ice extent may respond to a separate set of climatic/geochemical parameters. (orig.)

  10. Adjacency-preserving spatial treemaps

    Kevin Buchin

    2016-03-01

    Full Text Available Rectangular layouts, subdivisions of an outer rectangle into smaller rectangles, have many applications in visualizing spatial information, for instance in rectangular cartograms in which the rectangles represent geographic or political regions. A spatial treemap is a rectangular layout with a hierarchical structure: the outer rectangle is subdivided into rectangles that are in turn subdivided into smaller rectangles. We describe algorithms for transforming a rectangular layout that does not have this hierarchical structure, together with a clustering of the rectangles of the layout, into a spatial treemap that respects the clustering and also respects to the extent possible the adjacencies of the input layout.

  11. Characterization of winter foraging locations of Adélie penguins along the Western Antarctic Peninsula, 2001-2002

    Erdmann, Eric S.; Ribic, Christine A.; Patterson-Fraser, Donna L.; Fraser, William R.

    2011-07-01

    In accord with the hypotheses driving the Southern Ocean Global Ocean Ecosystems Dynamics (SO GLOBEC) program, we tested the hypothesis that the winter foraging ecology of a major top predator in waters off the Western Antarctic Peninsula (WAP), the Adélie penguin ( Pygoscelis adeliae), is constrained by oceanographic features related to the physiography of the region. This hypothesis grew from the supposition that breeding colonies in the WAP during summer are located adjacent to areas of complex bathymetry where circulation and upwelling processes appear to ensure predictable food resources. Therefore, we tested the additional hypothesis that these areas continue to contribute to the foraging strategy of this species throughout the non-breeding winter season. We used satellite telemetry data collected as part of the SO GLOBEC program during the austral winters of 2001 and 2002 to characterize individual penguin foraging locations in relation to bathymetry, sea ice variability within the pack ice, and wind velocity and divergence (as a proxy for potential areas with cracks and leads). We also explored differences between males and females in core foraging area overlap. Ocean depth was the most influential variable in the determination of foraging location, with most birds focusing their effort on shallow (penguin's foraging, the analysis of sea ice data of a higher resolution than was available for this study may help elucidate the role of sea ice in affecting Adélie penguin winter foraging behavior within the pack ice.

  12. Characterization of winter foraging locations of Adélie penguins along the Western Antarctic Peninsula, 2001–2002

    Erdmann, Eric S.; Ribic, Christine; Patterson-Fraser, Donna L.; Fraser, William R.

    2011-01-01

    In accord with the hypotheses driving the Southern Ocean Global Ocean Ecosystems Dynamics (SO GLOBEC) program, we tested the hypothesis that the winter foraging ecology of a major top predator in waters off the Western Antarctic Peninsula (WAP), the Adélie penguin (Pygoscelis adeliae), is constrained by oceanographic features related to the physiography of the region. This hypothesis grew from the supposition that breeding colonies in the WAP during summer are located adjacent to areas of complex bathymetry where circulation and upwelling processes appear to ensure predictable food resources. Therefore, we tested the additional hypothesis that these areas continue to contribute to the foraging strategy of this species throughout the non-breeding winter season. We used satellite telemetry data collected as part of the SO GLOBEC program during the austral winters of 2001 and 2002 to characterize individual penguin foraging locations in relation to bathymetry, sea ice variability within the pack ice, and wind velocity and divergence (as a proxy for potential areas with cracks and leads). We also explored differences between males and females in core foraging area overlap. Ocean depth was the most influential variable in the determination of foraging location, with most birds focusing their effort on shallow (penguin's foraging, the analysis of sea ice data of a higher resolution than was available for this study may help elucidate the role of sea ice in affecting Adélie penguin winter foraging behavior within the pack ice.

  13. Multibranch Antarctic Seismic Data Library facilitates research

    Cooper, Alan K.

    In 1991, investigators from 11 nations involved in Antarctic multichannel seismic (MCS) reflection research sought a way to keep the Antarctic Treaty's promise of open access to data, and in the process to encourage Earth-science research using seismic data. The Antarctic Seismic Data Library System for Cooperative Research (SDLS) was the solution, and is now a recommendation of the Antarctic Treaty Consultative Parties (ATCP). Today—at 12 branches spanning the world—researchers can access over 68,000 km of marine MCS data to use for cooperative research.More than 150,000 km of MCS data have been accumulated since 1976 by 13 countries on nearly 70 cruises. The majority of data now in the library cover the Ross Sea, Wilkes Land, and Prydz Bay sectors of the Antarctic margin, with smaller amounts from the Weddell Sea and the Antarctic Peninsula.

  14. Projected changes of Antarctic krill habitat by the end of the 21st century

    Piñones, Andrea; Fedorov, Alexey V.

    2016-08-01

    Climate change is rapidly shaping the living environment of the most abundant keystone species of the Antarctic marine food web, Antarctic krill. Projected future changes for the krill habitat include a sustained increase in ocean temperature and changes in sea ice and chlorophyll a. Here we investigate how these factors affect the early life history of krill and identify the regions around Antarctica where the impact will be greatest. Our tool is a temperature-dependent krill growth model forced by data from comprehensive greenhouse warming simulations. We find that by the year 2100 localized regions along the western Weddell Sea, isolated areas of the Indian Antarctic , and the Amundsen/Bellingshausen Sea will support successful spawning habitats for krill. The failure of potentially successful spawning will have a strong impact on the already declining adult populations with consequences for the Antarctic marine food web, having both ecological and commercial ramifications.

  15. Morphogenesis of Antarctic Paleosols: Martian Analogue

    Mahaney, W. C.; Dohm, J. M.; Baker, V. R.; Newsom, Horton E.; Malloch, D.; Hancock, R. G. V.; Campbell, Iain; Sheppard, D.; Milner, M. W.

    2001-11-01

    Samples of horizons in paleosols from the Quartermain Mountains of the Antarctic Dry Valleys (Aztec and New Mountain areas) were analyzed for their physical characteristics, mineralogy, chemical composition, and microbiology to determine the accumulation and movement of salts and other soluble constituents and the presence/absence of microbial populations. Salt concentrations are of special interest because they are considered to be a function of age, derived over time, in part from nearby oceanic and high-altitude atmospheric sources. The chemical composition of ancient Miocene-age paleosols in these areas is the direct result of the deposition and weathering of airborne-influxed salts and other materials, as well as the weathering of till derived principally from local dolerite and sandstone outcrops. Paleosols nearer the coast have greater contents of Cl, whereas near the inland ice sheet, nitrogen tends to increase on a relative basis. The accumulation and vertical distribution of salts and other soluble chemical elements indicate relative amounts of movement in the profile over long periods of time, in the order of several million years. Four of the six selected subsamples from paleosol horizons in two ancient soil profiles contained nil concentrations of bacteria and fungi. However, two horizons at depths of between 3 and 8 cm, in two profiles, yielded several colonies of the fungi Beauveria bassiana and Penicillium brevicompactum, indicating very minor input of organic carbon. Beauveria bassiana is often reported in association with insects and is used commercially for the biological control of some insect pests. Penicillium species are commonly isolated from Arctic, temperate, and tropical soils and are known to utilize a wide variety of organic carbon and nitrogen compounds. The cold, dry soils of the Antarctic bear a close resemblance to various present and past martian environments where similar weathering could occur and possible microbial populations

  16. Snow on Antarctic sea ice

    Massom, Robert A.; Eicken, Hajo; Hass, Christian; Jeffries, Martin O.; Drinkwater, Mark R.; Sturm, Matthew; Worby, Anthony P.; Wu, Xingren; Lytle, Victoria I.; Ushio, Shuki; Morris, Kim; Reid, Phillip A.; Warren, Stephen G.; Allison, Ian

    2001-08-01

    Snow on Antarctic sea ice plays a complex and highly variable role in air-sea-ice interaction processes and the Earth's climate system. Using data collected mostly during the past 10 years, this paper reviews the following topics: snow thickness and snow type and their geographical and seasonal variations; snow grain size, density, and salinity; frequency of occurrence of slush; thermal conductivity, snow surface temperature, and temperature gradients within snow; and the effect of snow thickness on albedo. Major findings include large regional and seasonal differences in snow properties and thicknesses; the consequences of thicker snow and thinner ice in the Antarctic relative to the Arctic (e.g., the importance of flooding and snow-ice formation); the potential impact of increasing snowfall resulting from global climate change; lower observed values of snow thermal conductivity than those typically used in models; periodic large-scale melt in winter; and the contrast in summer melt processes between the Arctic and the Antarctic. Both climate modeling and remote sensing would benefit by taking account of the differences between the two polar regions.

  17. Alterations of p53 and PCNA in cancer and adjacent tissues from concurrent carcinomas of the esophagus and gastric cardia in the same patient in Linzhou, a high incidence area for esophageal cancer in northern China

    Hong Chen; Li-Dong Wang; Mei Guo; She-Gan Gao; Hua-Qin Guo; Zong-Min Fan; Ji-Lin Li

    2003-01-01

    AIM: To characterize the alteration and significance of p53and PCNA in cancer and adjacent tissues of concurrent cancersfrom the esophagus and gastric cardia in the same patient.METHODS: P53 and PCNA protein accumulation in 25patients with concurrent cancers from the esophagus andgastric cardia (CC, concurrent carcinomas of esophagealsquamous cell carcinoma and gastric cardia adenocarcinoma)were detected by immunohistochemical method (ABC).RESULTS: In CC patients, both esophageal squamous cellcarcinoma (SCC) and gastric cardia adenocarcinoma (GCA)tissues showed different positive immunostaining extent ofp53 and PCNA protein (P>0.05). The positive immunostainingrates for p53 and PCNA were 60 % (15/25) and 92 % (23/25), respectively in SCC; and 40 % (10/25) and 88 % (22/25), respectively in GCA. "Diffuse" immunostaining patternwas frequently observed in both p53 and PCNA. Highcoincidence rates for p53 and PCNA positive staining wereobserved in SCC and GCA from the same patients, andaccounted for 56 % and 96 %. In SCC patients, with thelesions progressed from normal esophageal epithelium (NOR)to basal cell hyperplasia (BCH) to dysplasia (DYS) tocarcinomain situ (CIS) to SCC, the positive rates for p53were 27 %, 50 %, 50 %, 29 % and 72 %, and 55 %, 70 %,75 %, 71% and 93 % for PCNA, respectively. In GCA, withthe lesions progressed from normal gastric cardia epitheliumto DYS to CIS to GCA, the positive rates of p53 expressionwere 44 %, 27 %, 22 % and 36 % respectively, the differencewas not significant; the positive rates of PCNA proteinexpression were 67 %, 64 %, 67 % and 86 %, respectively.The x2 test, Fisher's Exact Test, Mantel-Haenszel x2 Testand Kappa Test were used for the statistics.CONCLUSION: The high coincident alterations for P53 andPCNA in SCC and GCA from the same patient indicate thepossibility of similar molecular basis, which providesimportant molecular basis and etiological clue for similargeographic distribution and risk factors in SCC and GCA.

  18. 75 FR 26287 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    2010-05-11

    ... future climate changes. Location Canada Glacier (ASPA 131), Taylor Dry Valley. Dates December 2, 2010 to... is Requested Enter Antarctic Specially Protected Areas (ASPA) and Import into the USA. The...

  19. 77 FR 37445 - Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    2012-06-21

    ... 1978 (Pub. L. 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has... assess the change in foraging behavior upon the arrival of whales in the penguin's foraging area...

  20. The circum-Antarctic sedimentary record; a dowsing rod for Antarctic ice in the Eocene

    Scher, H.

    2012-12-01

    where δ18O values are low and decrease to -15.5 when δ18O values are highest. In contrast there is not a significant change in the ɛNd values of fossil fish teeth across the δ18O excursion at ODP Site 738. Low variability in fossil fish tooth ɛNd values precludes a major reorganization of bottom water circulation that may otherwise have transported terrigenous sediment from distal areas. Thus, the results from this study provide very strong evidence for an increase in the amount of fine-grained terrigenous material that was discharged from the Prydz Bay drainage and/or a change in the sediment source. I argue that these data provide evidence for erosion/weathering of Antarctic basement rocks by small ice sheets that formed in the hinterland of the Prydz Bay drainage. The approach that will be presented holds great promise for identifying short-lived glaciations on Antarctica prior to the major development of ice sheets at the Eocene Oligocene boundary. Understanding the timing, frequency, and duration of these events is paramount to evaluating the processes and feedbacks that resulted in the global transition from greenhouse to icehouse. References: Roy, M., et al. (2007), Chemical Geology, 244, 507-519. van de Flierdt T, Goldstein SL, Hemming SR, et al, Earth and Planetary Science Letters, 2007, 259, Pages:432-441.

  1. The South Atlantic in the Fine-Resolution Antarctic Model

    D. P. Stevens

    Full Text Available The geographical area covered by the Fine-Resolution Antarctic Model (FRAM includes that part of the South Atlantic south of 24°S. A description of the dynamics and thermodynamics of this region of the model is presented. Both the mean and eddy fields in the model are in good agreement with reality, although the magnitude of the transients is somewhat reduced. The heat flux is northward and in broad agreement with many other estimates. Agulhas eddies are formed by the model and propagate westward into the Atlantic providing a mechanism for fluxing heat from the Indian Ocean. The confluence of the Brazil and Falkland currents produces a strong front and a large amount of mesoscale activity. In the less stratified regions to the south, topographic steering of the Antarctic circumpolar current is important.

  2. DINSAR measurement of glacier motion in Antarctic Grove Mountain

    CHENG Xiao; LI XiaoWen; SHAO Yun; LI Zhen

    2007-01-01

    Grove Mountain is an important nunatak region on East Antarctic Glacier that blocks the ice flow toward Lambert Glacier. The existence of nunataks and subglacial mountains leads to complex ice flow patterns, which are difficult to be measured by conventional ground-based methods. In this study, several JERS-1 and ERS-1/2 SAR images covering this area are used for 3-pass and 4-pass differential interferometric processing. The ice flow field of Grove Mountain and the eastern zone are derived and validated with related knowledge. The research shows that DINSAR is an effective method for measuring complex ice flow in Antarctic inland glacier. L-band DINSAR is more suitable for mid or fast ice flow than C-band over this region.

  3. JCADM, new directions in Antarctic data management

    Campbell, H.; de Bruin, T. F.

    2008-12-01

    The Joint Committee on Antarctic Data Management (JCADM) was established by the Scientific Committee on Antarctic Research (SCAR) and the Council of Managers of National Antarctic Programs (COMNAP), to assist in the fulfilment of the data management obligations imposed by the Antarctic Treaty (section III.1.c): "Scientific observations and results from Antarctica shall be exchanged and made freely available." JCADM comprises representatives of the National Antarctic Data Centres or national points of contact. Currently 31 nations around the world are represented in JCADM. So far, JCADM has been focussing on the coordination of the Antarctic Master Directory (AMD), the internationally accessible, web-based, searchable record of Antarctic and Southern Ocean data set descriptions. The AMD is directly integrated into the international Global Change Master Directory (GCMD) to help further merge Antarctic science into global science. The AMD is a resource for scientists to advertise the data they have collected and to search for data they may need. Currently, JCADM is in a transition phase, moving forward to provide data access. Existing systems and web services technology will be used as much as possible, to increase efficiency and prevent 're-inventing the wheel' This poster will give an overview of this process, the current status and the expected results.

  4. Impact of climate change on Antarctic krill

    Florentino De Souza Silva, A.P.; Atkinson, A.; Kawaguchi, S.; Bravo Rebolledo, E.; Franeker, van J.A.

    2012-01-01

    Antarctic krill Euphausia superba (hereafter ‘krill’) occur in regions undergoing rapid environmental change, particularly loss of winter sea ice. During recent years, harvesting of krill has increased, possibly enhancing stress on krill and Antarctic ecosystems. Here we review the overall impact of

  5. Analysis of Crust and Upper Mantle Structure in Ningxia and its Adjacent Area%宁夏及邻区地壳上地幔结构特征分析

    谢晓峰; 王伟涛; 崔瑾; 吕俊强; 姚琳

    2014-01-01

    介绍了宁夏及邻区1970年以来多种地球物理探测研究成果,揭示了该地区不同活动构造单元的深部地壳构造背景。分析表明,活动块体相互作用、地壳深部断裂、地壳低速体、速度结构的差异和岩性的不同、上地幔顶部隆起、莫霍界面较大的起伏以及复杂的壳幔过渡带等构造特征与该区域强震的形成和发生有较为密切的关系。最后讨论了该区域强震发生的机理。%Ningxia and its neighboring area are located in three blocks including the Erdos block, Alashan block and the Qinghai-Xizang block.There are many active faults in this area,such as the Haiyuan fault,the eastern piedmont fault of Helanshan,the Huanghe fault,and the Liupans-han fault.Because of the special stress environment in this area,all earthquakes of magnitude greater than 8 and most of those 5 to 7.9 occurred along the boundaries of the three active tecton-ics blocks.Researchers began exploration in this district in the 1960s and have used many methods such as wide-angle reflection and refraction seismic exploration,electrical prospecting,shallow seismic exploration,the gravity method,Global Positioning System (GPS),geodetic deformation survey,seismic array,and surveying and prospecting of active faults.Many valuable results have been obtained by using the various types of study methods.This paper summarizes the results of 40 years of such studies in this area by geoscientific researchers.The active block hypothesis states that strong earthquakes occur in such areas that the position wave velocity changes from high to low or the placement of the upper low-velocity body changes.Distribution of the geotem-perature field in this area shows that many strong earthquakes occur in the position of high tem-perature and anomalous temperature gradient.The differential movement of block interaction is very strong.The results of wide-angle reflection and refraction seismic exploration also indicate the

  6. An outline of the Antarctic minke whale assessment cruise (IWC/IDCR) in 1978/79 to 1980/81

    Hidehiro, Kato

    1982-01-01

    Since the 1978/79 Antarctic whaling season, extensive and systematic whale sightings and marking cruises on the Antarctic minke whales have been carried out under the International Whaling Commission/International Decade of Cetacean Research (IWC/IDCR) programme. The programme was carried out in the Southern Hemisphere Whaling Areas (for baleen whales) IV (70°-130°E), III (0°-70°E) and V (130°E-170°W) during the Antarctic summer season in 1978/79,1979/80 and 1980/81,respectively. The total nu...

  7. Compressed Adjacency Matrices: Untangling Gene Regulatory Networks.

    Dinkla, K; Westenberg, M A; van Wijk, J J

    2012-12-01

    We present a novel technique-Compressed Adjacency Matrices-for visualizing gene regulatory networks. These directed networks have strong structural characteristics: out-degrees with a scale-free distribution, in-degrees bound by a low maximum, and few and small cycles. Standard visualization techniques, such as node-link diagrams and adjacency matrices, are impeded by these network characteristics. The scale-free distribution of out-degrees causes a high number of intersecting edges in node-link diagrams. Adjacency matrices become space-inefficient due to the low in-degrees and the resulting sparse network. Compressed adjacency matrices, however, exploit these structural characteristics. By cutting open and rearranging an adjacency matrix, we achieve a compact and neatly-arranged visualization. Compressed adjacency matrices allow for easy detection of subnetworks with a specific structure, so-called motifs, which provide important knowledge about gene regulatory networks to domain experts. We summarize motifs commonly referred to in the literature, and relate them to network analysis tasks common to the visualization domain. We show that a user can easily find the important motifs in compressed adjacency matrices, and that this is hard in standard adjacency matrix and node-link diagrams. We also demonstrate that interaction techniques for standard adjacency matrices can be used for our compressed variant. These techniques include rearrangement clustering, highlighting, and filtering.

  8. Hydrocarbon degradation by antarctic bacteria

    Cavanagh, J.A.E.; Nichols, P.D.; McMeekin, T.A.; Franzmann, P.D. [Univ. of Tasmania (Australia)] [and others

    1996-12-31

    Bacterial cultures obtained from sediment samples collected during a trial oil spill experiment conducted at Airport beach, Eastern Antarctica were selectively enriched for n-alkane-degrading and phenanthrenedegrading bacteria. Samples were collected from a control site and sites treated with different hydrocarbon mixtures - Special Antarctic blend (SAB), BP-Visco and orange roughy oils. One set of replicate sites was also treated with water from Organic Lake which had previously been shown to contain hydrocarbon-degrading bacteria. No viable bacteria were obtained from samples collected from sites treated with orange roughy oil. Extensive degradation of n-alkanes by enrichment cultures obtained from sites treated with SAB and BP-Visco occurred at both 25{degrees}C and 10{degrees}C. Extensive degradation of phenanthrene also occurred in enrichment cultures from these sites grown at 25{degrees}C. Concurrent increases of polar lipid in these cultures were also observed. The presence of 1,4-naphthaquinone and 1-naphthol during the growth of the cultures on phenanthrene is unusual and warrants further investigation of the mechanism of phenanthrene-degradation by these Antarctic bacteria.

  9. 33 CFR 151.06 - Special areas.

    2010-07-01

    ... Implementation of MARPOL 73/78 and the Protocol on Environmental Protection to the Antarctic Treaty as it..., 51°16.9′ E) and the Ras Fartak (15°35′ N, 52°13.8′ E). (7) The Antarctic areas means the sea south...

  10. Historic and Current Distributions of River Otters (Lontra canadensis and (Lontra longicaudis in the Río Grande or Río Bravo del Norte Drainage of Colorado and New Mexico, USA and of Chihuahua, Mexico and Adjacent Areas

    Paul Polechla

    2009-10-01

    Full Text Available The Río Grande drainage is an important and imperiled wetland of the US/Mexican border arid lands. There is a desire to restore otter populations in this river by interested parties. In order to follow IUCN guidelines for restoration, biologists need learn more fully the situation prior to implementation of restoration management. A prerequisite for proper restoration conservation is to know the organism’s taxonomy (i.e., what taxa or species and subspecies one is dealing with, distribution, and relative abundance. The historic and current distribution of the Nearctic otter (Lontra canadensis and Neotropical otter (L. longicaudis in the borderlands of US and Mexico are reviewed in this paper. The evidence indicates that otters were native to the Río Grande valley and has been recorded in the languages and customs of Native Americans such as the Pueblo people prior to European settlement of the area. The first Spanish documents we were able to find whereby otters were recorded, date to the middle 16th century. Otters during historical times were probably more numerous than previously thought and one of the first wildlife laws in the borderlands revolved around a moratorium on trapping the otter and beaver. Presently, populations of otters occur in 1 the Río San Pedro of Chihuahua, a tributary of the Río Conchos entering the Río Grande from the southeast, 2 the upper Río Grande near the Colorado/New Mexico border, and 3 the middle Pecos River in southeastern New Mexico entering the Río Grande from the west. These observations are corroborated by multiple observations by competent observers and in the case of the first population, otter photos and sign. These populations are centered on areas with macro-habitats characterized by a river flowing through 1 deep canyons, or 2 ancillary wetlands. Considerable more detailed survey work is needed to determine the full extent of the distribution of otters in the Río Grande drainage. A genetic

  11. Underwater Optics in Sub-Antarctic and Antarctic Coastal Ecosystems.

    Huovinen, Pirjo; Ramírez, Jaime; Gómez, Iván

    2016-01-01

    Understanding underwater optics in natural waters is essential in evaluating aquatic primary production and risk of UV exposure in aquatic habitats. Changing environmental conditions related with global climate change, which imply potential contrasting changes in underwater light climate further emphasize the need to gain insights into patterns related with underwater optics for more accurate future predictions. The present study evaluated penetration of solar radiation in six sub-Antarctic estuaries and fjords in Chilean North Patagonian region (39-44°S) and in an Antarctic bay (62°S). Based on vertical diffuse attenuation coefficients (Kd), derived from measurements with a submersible multichannel radiometer, average summer UV penetration depth (z1%) in these water bodies ranged 2-11 m for UV-B (313 nm), 4-27 m for UV-A (395 nm), and 7-30 m for PAR (euphotic zone). UV attenuation was strongest in the shallow Quempillén estuary, while Fildes Bay (Antarctica) exhibited the highest transparency. Optically non-homogeneous water layers and seasonal variation in transparency (lower in winter) characterized Comau Fjord and Puyuhuapi Channel. In general, multivariate analysis based on Kd values of UV and PAR wavelengths discriminated strongly Quempillén estuary and Puyuhuapi Channel from other study sites. Spatial (horizontal) variation within the estuary of Valdivia river reflected stronger attenuation in zones receiving river impact, while within Fildes Bay a lower spatial variation in water transparency could in general be related to closeness of glaciers, likely due to increased turbidity through ice-driven processes. Higher transparency and deeper UV-B penetration in proportion to UV-A/visible wavelengths observed in Fildes Bay suggests a higher risk for Antarctic ecosystems reflected by e.g. altered UV-B damage vs. photorepair under UV-A/PAR. Considering that damage repair processes often slow down under cool temperatures, adverse UV impact could be further

  12. Cyclone formation and development in the Antarctic Prydz Bay

    解思梅; 梅山; 刘克威; 魏立新

    2002-01-01

    Using meteorological data of field observation in 1990~ 2000 , especially polar orbit highresolution NOAA satellite cloud maps received from the Antarctic expedition vessel since 1997, the formation and development of the Prydz Bay cyclone are studied in this paper. Some new viewpoints are suggested such as: when surround-polar cyclone enters the Prydz Bay, it can also intensify and develop in summer; cyclone can also develop in the easterlies in this bay. These view points revise old uncomplete view point that the Prydz Bay is a burial ground of cyclone, and also further consummate formation-development theory of surround-cyclone in the Antarctic westerlies and cyclone in the Antarctic easterlies. In this paper, the mechanism of ice-air-sea interaction in the Prydz Bay is studied, and the physical process of cyclone formation-development is explained. By use of wholly dynamic transportation method, an energy exchange case of a cyclone, which explosively developed after entering the Prydz Bay, is calculated. In the open water area, momentum flux is - 2.205 N/m2, sensible heat flux is 486.69 W/m2, and latent heat flux is 261.84 W/m2. It is larger than values of westerlies burst over the Pacific. The heat transferred from ocean to atmosphere in form of sensible and latent heat promotes cyclone development rapidly. In this case wind force was as strong as 12 grade, with 10 minutes average wind speed of 38 m/s, and instantaneous wind speed of 100 m/s which broke the wind speed record of 96 m/s in the Antarctic (Wendler and Kodama).

  13. Antarctic krill 454 pyrosequencing reveals chaperone and stress transcriptome.

    Melody S Clark

    Full Text Available BACKGROUND: The Antarctic krill Euphausia superba is a keystone species in the Antarctic food chain. Not only is it a significant grazer of phytoplankton, but it is also a major food item for charismatic megafauna such as whales and seals and an important Southern Ocean fisheries crop. Ecological data suggest that this species is being affected by climate change and this will have considerable consequences for the balance of the Southern Ocean ecosystem. Hence, understanding how this organism functions is a priority area and will provide fundamental data for life history studies, energy budget calculations and food web models. METHODOLOGY/PRINCIPAL FINDINGS: The assembly of the 454 transcriptome of E. superba resulted in 22,177 contigs with an average size of 492bp (ranging between 137 and 8515bp. In depth analysis of the data revealed an extensive catalogue of the cellular chaperone systems and the major antioxidant proteins. Full length sequences were characterised for the chaperones HSP70, HSP90 and the super-oxide dismutase antioxidants, with the discovery of potentially novel duplications of these genes. The sequence data contained 41,470 microsatellites and 17,776 Single Nucleotide Polymorphisms (SNPs/INDELS, providing a resource for population and also gene function studies. CONCLUSIONS: This paper details the first 454 generated data for a pelagic Antarctic species or any pelagic crustacean globally. The classical "stress proteins", such as HSP70, HSP90, ferritin and GST were all highly expressed. These genes were shown to be over expressed in the transcriptomes of Antarctic notothenioid fish and hypothesized as adaptations to living in the cold, with the associated problems of decreased protein folding efficiency and increased vulnerability to damage by reactive oxygen species. Hence, these data will provide a major resource for future physiological work on krill, but in particular a suite of "stress" genes for studies understanding

  14. Microbial ecology of Antarctic aquatic systems.

    Cavicchioli, Ricardo

    2015-11-01

    The Earth's biosphere is dominated by cold environments, and the cold biosphere is dominated by microorganisms. Microorganisms in cold Southern Ocean waters are recognized for having crucial roles in global biogeochemical cycles, including carbon sequestration, whereas microorganisms in other Antarctic aquatic biomes are not as well understood. In this Review, I consider what has been learned about Antarctic aquatic microbial ecology from 'omic' studies. I assess the factors that shape the biogeography of Antarctic microorganisms, reflect on some of the unusual biogeochemical cycles that they are associated with and discuss the important roles that viruses have in controlling ecosystem function.

  15. Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences

    Jerez, Silvia [Area de Toxicologia, Facultad de Veterinaria, Universidad de Murcia, Campus de Espinardo, 30100 Murcia (Spain); Motas, Miguel, E-mail: motas@um.es [Area de Toxicologia, Facultad de Veterinaria, Universidad de Murcia, Campus de Espinardo, 30100 Murcia (Spain); Palacios, Maria Jose; Valera, Francisco [Departamento de Ecologia Funcional y Evolutiva, Estacion Experimental de Zonas Aridas, CSIC, Carretera de Sacramento s/n, 04120 La Canada de San Urbano, Almeria (Spain); Cuervo, Jose Javier; Barbosa, Andres [Departamento de Ecologia Funcional y Evolutiva, Estacion Experimental de Zonas Aridas, CSIC, Carretera de Sacramento s/n, 04120 La Canada de San Urbano, Almeria (Spain); Departamento de Ecologia Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, C/Jose Gutierrez Abascal 2, 28006 Madrid (Spain)

    2011-10-15

    Antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. Concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were determinated by ICP-MS in feathers (n = 207 individuals) of gentoo, chinstrap and Adelie penguin collected in 8 locations throughout the Antarctic Peninsula (2006-2007). The highest levels of several elements were found in samples from King George Island (8.08, 20.29 and 1.76 {mu}g g{sup -1} dw for Cr, Cu and Pb, respectively) and Deception Island (203.13, 3.26 and 164.26 {mu}g g{sup -1} dw for Al, Mn and Fe, respectively), where probably human activities and large-scale transport of pollutants contribute to increase metal levels. Concentrations of Cr, Mn, Cu, Se or Pb, which are similar to others found in different regions of the world, show that some areas in Antarctica are not utterly pristine. - Highlights: > We study levels of trace elements in feathers of Antarctic penguins. > Eight different rookeries throughout the Antarctic Peninsula were sampled. > Interspecific (gentoo, chinstrap, Adelie) and geographical differences were tested. > Relatively high metal levels were found in areas with major human presence. > Penguin feather can be useful for metals monitoring in the Antarctic environment. - Trace element levels in feathers of three penguin species from the Antarctic Peninsula indicate the presence of pollution in certain locations.

  16. Modelling the effects of environmental conditions on the acoustic occurrence and behaviour of Antarctic blue whales.

    Shabangu, Fannie W; Yemane, Dawit; Stafford, Kathleen M; Ensor, Paul; Findlay, Ken P

    2017-01-01

    Harvested to perilously low numbers by commercial whaling during the past century, the large scale response of Antarctic blue whales Balaenoptera musculus intermedia to environmental variability is poorly understood. This study uses acoustic data collected from 586 sonobuoys deployed in the austral summers of 1997 through 2009, south of 38°S, coupled with visual observations of blue whales during the IWC SOWER line-transect surveys. The characteristic Z-call and D-call of Antarctic blue whales were detected using an automated detection template and visual verification method. Using a random forest model, we showed the environmental preferences pattern, spatial occurrence and acoustic behaviour of Antarctic blue whales. Distance to the southern boundary of the Antarctic Circumpolar Current (SBACC), latitude and distance from the nearest Antarctic shores were the main geographic predictors of blue whale call occurrence. Satellite-derived sea surface height, sea surface temperature, and productivity (chlorophyll-a) were the most important environmental predictors of blue whale call occurrence. Call rates of D-calls were strongly predicted by the location of the SBACC, latitude and visually detected number of whales in an area while call rates of Z-call were predicted by the SBACC, latitude and longitude. Satellite-derived sea surface height, wind stress, wind direction, water depth, sea surface temperatures, chlorophyll-a and wind speed were important environmental predictors of blue whale call rates in the Southern Ocean. Blue whale call occurrence and call rates varied significantly in response to inter-annual and long term variability of those environmental predictors. Our results identify the response of Antarctic blue whales to inter-annual variability in environmental conditions and highlighted potential suitable habitats for this population. Such emerging knowledge about the acoustic behaviour, environmental and habitat preferences of Antarctic blue whales is

  17. Modelling the effects of environmental conditions on the acoustic occurrence and behaviour of Antarctic blue whales

    Shabangu, Fannie W.; Yemane, Dawit; Stafford, Kathleen M.; Ensor, Paul; Findlay, Ken P.

    2017-01-01

    Harvested to perilously low numbers by commercial whaling during the past century, the large scale response of Antarctic blue whales Balaenoptera musculus intermedia to environmental variability is poorly understood. This study uses acoustic data collected from 586 sonobuoys deployed in the austral summers of 1997 through 2009, south of 38°S, coupled with visual observations of blue whales during the IWC SOWER line-transect surveys. The characteristic Z-call and D-call of Antarctic blue whales were detected using an automated detection template and visual verification method. Using a random forest model, we showed the environmental preferences pattern, spatial occurrence and acoustic behaviour of Antarctic blue whales. Distance to the southern boundary of the Antarctic Circumpolar Current (SBACC), latitude and distance from the nearest Antarctic shores were the main geographic predictors of blue whale call occurrence. Satellite-derived sea surface height, sea surface temperature, and productivity (chlorophyll-a) were the most important environmental predictors of blue whale call occurrence. Call rates of D-calls were strongly predicted by the location of the SBACC, latitude and visually detected number of whales in an area while call rates of Z-call were predicted by the SBACC, latitude and longitude. Satellite-derived sea surface height, wind stress, wind direction, water depth, sea surface temperatures, chlorophyll-a and wind speed were important environmental predictors of blue whale call rates in the Southern Ocean. Blue whale call occurrence and call rates varied significantly in response to inter-annual and long term variability of those environmental predictors. Our results identify the response of Antarctic blue whales to inter-annual variability in environmental conditions and highlighted potential suitable habitats for this population. Such emerging knowledge about the acoustic behaviour, environmental and habitat preferences of Antarctic blue whales is

  18. Abundance, viability and culturability of Antarctic bacteria

    LokaBharathi, P.A.; DeSouza, M.J.B.D.; Nair, S.; Chandramohan, D.

    The viability of total number of bacteria decide the mineralisation rate in any ecosystem and ultimately the fertility of the region. This study aims at establishing the extent of viability in the standing stock of the Antarctic bacterial population...

  19. Ross Ice Shelf, Antarctic Ice and Clouds

    1991-01-01

    In this view of Antarctic ice and clouds, (56.5S, 152.0W), the Ross Ice Shelf of Antarctica is almost totally clear, showing stress cracks in the ice surface caused by wind and tidal drift. Clouds on the eastern edge of the picture are associated with an Antarctic cyclone. Winds stirred up these storms have been known to reach hurricane force.

  20. What Controls the Size of the Antarctic Ozone Hole?

    Bhartia, P. K. (Technical Monitor); Newman, Paul A.; Kawa, S. Randolph; Nash, Eric R.

    2002-01-01

    The Antarctic ozone hole is a region of extremely large ozone depletion that is roughly centered over the South Pole. Since 1979, the area coverage of the ozone hole has grown from near zero size to over 24 Million square kilometers. In the 8-year period from 1981 to 1989, the area expanded by 18 Million square kilometers. During the last 5 years, the hole has been observed to exceed 25 Million square kilometers over brief periods. We will review these size observations, the size trends, and the interannual variability of the size. The area is derived from the area enclosed by the 220 DU total ozone contour. We will discuss the rationale for the choice of 220 DU: 1) it is located near the steep gradient between southern mid-latitudes and the polar region, and 2) 220 DU is a value that is lower than the pre- 1979 ozone observations over Antarctica during the spring period. The phenomenal growth of the ozone hole was directly caused by the increases of chlorine and bromine compounds in the stratosphere. In this talk, we will show the relationship of the ozone hole's size to the interannual variability of Antarctic spring temperatures. In addition, we will show the relationship of these same temperatures to planetary-scale wave forcings.

  1. On the Size of the Antarctic Ozone Hole

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph

    2002-01-01

    The Antarctic ozone hole is a region of extremely large ozone depletion that is roughly centered over the South Pole. Since 1979, the area coverage of the ozone hole has grown from near zero size to over 24 Million sq km. In the 8-year period from 1981 to 1989, the area expanded by 18 Million sq km. During the last 5 years, the hole has been observed to exceed 25 Million sq km over brief periods. In the spring of 2002, the size of the ozone hole barely reached 20 Million sq km for only a couple of days. We will review these size observations, the size trends, and the interannual variability of the size. The area is derived from the area enclosed by the 220 DU total ozone contour. We will discuss the rationale for the choice of 220 DU: 1) it is located near the steep gradient between southern mid-latitudes and the polar region, and 2) 220 DU is a value that is lower than the pre-1979 ozone observations over Antarctica during the spring period. The phenomenal growth of the ozone hole was directly caused by the increases of chlorine and bromine compounds in the stratosphere. In this talk, we will show the relationship of the ozone hole's size to the interannual variability of Antarctic spring temperatures. In addition, we will show the relationship of these same temperatures to planetary-scale wave forcings.

  2. Pteropods and climate off the Antarctic Peninsula

    Loeb, Valerie J.; Santora, Jarrod A.

    2013-09-01

    Shelled (thecosome) and naked (gymnosome) pteropods are regular, at times abundant, members of Southern Ocean zooplankton assemblages. Regionally, shelled species can play a major role in food webs and carbon cycling. Because of their aragonite shells thecosome pteropods may be vulnerable to the impacts of ocean acidification; without shells they cannot survive and their demise would have major implications for food webs and carbon cycling in the Southern Ocean. Additionally, pteropod species in the southwest Atlantic sector of the Southern Ocean inhabit a region of rapid warming and climate change, the impacts of which are predicted to be observed as poleward distribution shifts. Here we provide baseline information on intraseasonal, interannual and longer scale variability of pteropod populations off the Antarctic Peninsula between 1994 and 2009. Concentrations of the 4 dominant taxa, Limacina helicina antarctica f. antarctica, Clio pyramidata f. sulcata, Spongiobranchaea australis and Clione limacina antarctica, are similar to those monitored during the 1928-1935 Discovery Investigations and reflect generally low values but with episodic interannual abundance peaks that, except for C. pyr. sulcata, are related to basin-scale climate forcing associated with the El Niño-Southern Oscillation (ENSO) climate mode. Significant abundance increases of L. helicina and S. australis after 1998 were associated with a climate regime shift that initiated a period dominated by cool La Niña conditions and increased nearshore influence of the Antarctic Circumpolar Current (ACC). This background information is essential to assess potential future changes in pteropod species distribution and abundance associated with ocean warming and acidification. construct maps of pteropod spatial frequency and mean abundance to assess their oceanographic associations; quantify pteropod abundance anomalies for comparing intraseasonal and interannual variability relative to m-3 environmental

  3. Bedrock geology of the northern Columbia Plateau and adjacent areas

    Swanson, D. A.; Wright, T. L.

    1978-01-01

    The Columbia Plateau is surrounded by a complex assemblage of highly deformed Precambrian to lower Tertiary continental and oceanic rocks that reflects numerous episodes of continental accretion. The plateau itself is comprised of the Columbia River basalt group formed between about 16.5 x 1 million years B.P. and 6 x 1 million years B.P. Eruptions were infrequent between about 14 and 6 x 1 million years B.P., allowing time for erosion and deformation between successive outpourings. The present-day courses of much of the Snake River, and parts of the Columbia River, across the plateau date from this time. Basalt produced during this waning activity is more heterogeneous chemically and isotopically than older flows, reflecting its prolonged period of volcanism.

  4. Interactions and Spreading of Adjacent Large Area Fires

    1986-03-31

    1985] and a city such as Hamburg for which the load was estimated at 157 kg/m 2 [Carrier, Fendell , and Feldman, 1985]. The caloric equivalent of those...Protec- tion Association, Boston, Massachusetts, 1951. Carrier, G. F., F. E. Fendell , and P. S. Feldman, "Firestorms," J. Heat Trans., Vol. 107, 1985...ATTN: C SCAWTHORN TRW ELECTRONICS & DEFENSE SECTOR ATTN: F FENDELL FACTORY MUTUAL RESEARCH CORP ATTN: R FRIEDMAN 37 KAL""h -XZ1 38 1 I

  5. Quaternary geology of the Channeled Scabland and adjacent areas

    Baker, V. R.

    1978-01-01

    The quaternary history of the channeled scabland is characterized by discrete episodes of catastrophic flooding and prolonged periods of loess accumulation and soil formation. The loess sequence was correlated with Richmond's Rocky Mountain glacial chronology. At least five major catastrophic flood events occurred in the general vicinity of the channeled scabland. The earliest episode occurred prior to the extensive deposition of the Palouse formation. The last major episode of flooding occurred between about 18,000 and 13,000 years ago. It probably consisted of two outbursts from glacial Lake Missoula.

  6. The SCAR Standing Committee on Antarctic Data Management - new directions in access to Antarctic research data

    de Bruin, T.

    2009-04-01

    The SCAR Standing Committee on Antarctic Data Management (SC-ADM) was established by the Scientific Committee on Antarctic Research (SCAR) and the Council of Managers of National Antarctic Programs (COMNAP), to assist in the fulfillment of the data management obligations imposed by the Antarctic Treaty (section III.1.c): "Scientific observations and results from Antarctica shall be exchanged and made freely available." SC-ADM comprises representatives of the National Antarctic Data Centres or national points of contact. Currently 31 nations around the world are represented in SC-ADM. So far, SC-ADM has been focussing on the coordination of the Antarctic Master Directory (AMD), the internationally accessible, web-based, searchable record of Antarctic and Southern Ocean data set descriptions. The AMD is directly integrated into the international Global Change Master Directory (GCMD) to help further merge Antarctic science into global science. The AMD is a resource for scientists to advertise the data they have collected and to search for data they may need. Currently, SC-ADM is in a transition phase, moving forward to provide data access. Existing systems and web services technology will be used as much as possible, to increase efficiency and prevent 're-inventing the wheel' This poster will give an overview of this process, the current status and the expected results.

  7. The impact of tourists on Antarctic tardigrades: an ordination-based model

    Sandra J. McInnes

    2013-05-01

    Full Text Available Tardigrades are important members of the Antarctic biota yet little is known about their role in the soil fauna or whether they are affected by anthropogenic factors. The German Federal Environment Agency commissioned research to assess the impact of human activities on soil meiofauna at 14 localities along the Antarctic peninsula during the 2009/2010 and 2010/2011 austral summers. We used ordination techniques to re-assess the block-sampling design used to compare areas of high and low human impact, to identify which of the sampled variables were biologically relevant and/or demonstrated an anthropogenic significance. We found the most significant differences between locations, reflecting local habitat and vegetation factor, rather than within-location anthropogenic impact. We noted no evidence of exotic imports but report on new maritime Antarctic sample sites and habitats.

  8. Antarctic last interglacial isotope peak in response to sea ice retreat not ice-sheet collapse.

    Holloway, Max D; Sime, Louise C; Singarayer, Joy S; Tindall, Julia C; Bunch, Pete; Valdes, Paul J

    2016-08-16

    Several studies have suggested that sea-level rise during the last interglacial implies retreat of the West Antarctic Ice Sheet (WAIS). The prevalent hypothesis is that the retreat coincided with the peak Antarctic temperature and stable water isotope values from 128,000 years ago (128 ka); very early in the last interglacial. Here, by analysing climate model simulations of last interglacial WAIS loss featuring water isotopes, we show instead that the isotopic response to WAIS loss is in opposition to the isotopic evidence at 128 ka. Instead, a reduction in winter sea ice area of 65±7% fully explains the 128 ka ice core evidence. Our finding of a marked retreat of the sea ice at 128 ka demonstrates the sensitivity of Antarctic sea ice extent to climate warming.

  9. Evaluation of soil bioremediation techniques in an aged diesel spill at the Antarctic Peninsula

    de Jesus, Hugo E.; Peixoto, Raquel S.; Cury, Juliano C.; van Elsas, Jan D.; Rosado, Alexandre S.

    2015-01-01

    Many areas on the Antarctic continent already suffer from the direct and indirect influences of human activities. The main cause of contamination is petroleum hydrocarbons because this compound is used as a source of energy at the many research stations around the continent. Thus, the current study

  10. A Longitudinal Study of Disease Incidence among Antarctic Winter-Over Personnel.

    1986-02-01

    Parainfluehzavirus upper respiratory infections at McMurdo Station during the astral summer 1975-76. Antarctic J. U.S., 1979; 14:186- 7. 15. Taylor AJ...ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT , TASK AREA & WORK UNIT NUMBERS Naval Health Research Center P.O. Box 85122 MROOO.01.01-6035

  11. 77 FR 4060 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    2012-01-26

    ... to take from the Palmer Station area approximately 20 brown marine algae, 30 green marine algae, 10 red marine algae, and 10 diatom marine algae to sublimate cultures of ] filamentous Antarctic... interactions of epiphytic and endophytic algae (both filamentous macroalgae and diatoms) with larger...

  12. 77 FR 3799 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    2012-01-25

    ... plans to take from the Palmer Station area approximately 20 brown marine algae, 30 green marine algae, 10 red marine algae, and 10 diatom marine algae to sublimate cultures of filamentous Antarctic... interactions of epiphytic and endophytic algae (both filamentous macroalgae and diatoms) with larger...

  13. Ciliate biogeography in Antarctic and Arctic freshwater ecosystems: endemism or global distribution of species?

    Petz, Wolfgang; Valbonesi, Alessandro; Schiftner, Uwe; Quesada, Antonio; Cynan Ellis-Evans, J

    2007-02-01

    Ciliate diversity was investigated in situ in freshwater ecosystems of the maritime (South Shetland Islands, mainly Livingston Island, 63 degrees S) and continental Antarctic (Victoria Land, 75 degrees S), and the High Arctic (Svalbard, 79 degrees N). In total, 334 species from 117 genera were identified in both polar regions, i.e. 210 spp. (98 genera) in the Arctic, 120 spp. (73 genera) in the maritime and 59 spp. (41 genera) in the continental Antarctic. Forty-four species (13% of all species) were common to both Arctic and Antarctic freshwater bodies and 19 spp. to both Antarctic areas (12% of all species). Many taxa are cosmopolitans but some, e.g. Stentor and Metopus spp., are not, and over 20% of the taxa found in any one of the three areas are new to science. Cluster analysis revealed that species similarity between different biotopes (soil, moss) within a study area was higher than between similar biotopes in different regions. Distinct differences in the species composition of freshwater and terrestrial communities indicate that most limnetic ciliates are not ubiquitously distributed. These observations and the low congruence in species composition between both polar areas, within Antarctica and between high- and temperate-latitude water bodies, respectively, suggest that long-distance dispersal of limnetic ciliates is restricted and that some species have a limited geographical distribution.

  14. Latest tendency in the Antarctic ozone longitudinal distribution

    Milinevsky, Gennadi; Grytsai, Asen; Klekociuk, Andrew; Evtushevsky, Olexander

    2014-05-01

    Significant ozone depletion was observed within the southern polar vortex during spring in the 1980s - early 1990s. Later, a stabilization in total ozone levels and ozone hole area has been observed. Atmosphere models predict a consequent recovery of the Antarctic ozone. Nevertheless, identification of the long-term processes is complicated by high interannual variability hiding their general regularities. In particular, a large stratosphere warming in 2002 resulted in significant increase in total ozone levels. The Antarctic ozone hole is formed inside polar stratospheric vortex, which is under influence of large-scale planetary waves. The components of the quasi-stationary wave (QSW) in the spring Southern Hemisphere (SH) stratosphere is mainly contributed by zonal wave number 1 which in turn determines the location of the total ozone extremes in spring: QSW minimum (maximum) is located in the South Atlantic (Australian) sector. In our work the satellite data of TOMS/Nimbus-7, TOMS/Earth Probe and OMI/Aura (http://ozoneaq.gsfc.nasa.gov/) have been used to investigate longitudinal distribution of the total ozone in Antarctic region. The gap in these satellite observations (1993-1995) was filled by the Multi-Sensor Reanalysis data (http://www.temis.nl/). Ozone distribution in the SH high and mid latitudes 80-50S were analyzed for southern spring season including months from September to November. The zonal distribution is considered along seven latitude circles from 80S to 50S with step of five degrees. To distinguish long-term processes and to obtain a quasi-stationary pattern, daily September - November ozone was averaged. Our previous study demonstrated a systematic eastward shift of the QSW minimum region. In this study, we extended the analysis to 2013 and obtained new results that exhibited a probable cessation in that eastward shift. Polynomial fit for all chosen latitudes is even evidence of a change in the tendency to opposite. It more time needs to

  15. Controls and variability of solute and sedimentary fluxes in Antarctic and sub-Antarctic Environments

    Zwolinski, Zbigniew

    2015-04-01

    The currently prepared SEDIBUD Book on "Source-to-Sink Fluxes in Undisturbed Cold Environments" (edited by Achim A. Beylich, John C. Dixon and Zbigniew Zwolinski and published by Cambridge University Press) is summarizing and synthesizing the achievements of the International Association of Geomorphologists` (I.A.G./A.I.G.) Working Group SEDIBUD (Sediment Budgets in Cold Environments), which has been active since 2005 (http://www.geomorph.org/wg/wgsb.html). The book comprises five parts. One of them is part about sub-Antarctic and Antarctic Environments. This part "Sub-Antarctic and Antarctic Environments" describes two different environments, namely oceanic and continental ones. Each part contains results of research on environmental drivers and rates of contemporary solute and sedimentary fluxes in selected sites. Apart from describing the environmental conditions of the whole continent of Antarctica and sub-Antarctic islands (Zb.Zwolinski, M.Kejna, A.N.Lastochkin, A.Zhirov, S.Boltramovich) this part of the book characterizes terrestrial polar oases free from multi-year ice and snow covers (Zb.Zwolinski). The detailed results of geoecological and sedimentological research come from different parts of Antarctica. Antarctic continental shelf (E.Isla) is an example of sub-Antarctic oceanic environment. South Shetlands, especially King George Island (Zb.Zwolinski, M.Kejna, G.Rachlewicz, I.Sobota, J.Szpikowski), is an example of sub-Antarctic terrestrial environment. Antarctic Peninsula (G.Vieira, M.Francelino, J.C.Fernandes) and surroundings of McMurdo Dry Valleys (W.B.Lyons, K.A.Welch, J.Levy, A.Fountain, D.McKnight) are examples of Antarctic continental environments. The key goals of the Antarctic and sub-Antarctic book chapters are following: (i) identify the main environmental drivers and rates of contemporary solute and sedimentary fluxes, and (ii) model possible effects of projected climate change on solute and sedimentary fluxes in cold climate environments

  16. Microbiology and Geochemistry of Antarctic Paleosols

    Mahaney, W. C.; Malloch, D.; Hancock, R. G. V.; Campbell, I. B.; Sheppard, D.

    2000-08-01

    Samples of ancient soils from horizons in paleosols from the Quartermain Mountains (Aztec and New Mountain areas of the Antarctic Dry Valleys) were analyzed for their chemical composition and microbiology to determine the accumulation and movement of salts and other soluble constituents. The salt concentrations are of special interest because they are considered to be a function of age, derived in part from nearby oceanic and high altitude atmospheric sources. The geochemistry of ancient Miocene-age paleosols in these areas is the direct result of the deposition and weathering of till, derived principally from dolerite and sandstone source rock, in association with airborne-influxed salts. Paleosols nearer the coast have greater contents of chlorine, and farther inland near the Inland Ice Sheet, nitrogen tends to increase on a relative basis. The accumulation and vertical distribution of salts and other soluble chemical elements indicate relative amounts of movement in the profile over long periods of time, to the order of several million years. Iron, both in total concentration and in the form of various extracts, indicates it can be used as a geochronometer to assess the buildup of goethite plus hematite over time in the paleosols. Trends for ferrihydrite, a partially soluble Fe-hydroxide, shows limited profile translocation that might be related to the movement of salt. Six of the eight selected subsamples from paleosol horizons in three soil profiles contained nil concentrations of bacteria and fungi. However, two horizons at depths of between three to eight centimeters yielded several colonies of the fungi Beauveria bassiana and Penicillium spp., indicating some input of organic carbon. Beauveria bassiana is often reported in association with insects and is used commercially for the biological control of some insect pests. Penicillium species are commonly isolated from Arctic, temperate and tropical soils and are known to utilize a wide variety of organic

  17. Mapping and Assessing Variability in the Antarctic Marginal Ice Zone, the Pack Ice and Coastal Polynyas

    Stroeve, Julienne; Jenouvrier, Stephanie

    2016-04-01

    Sea ice variability within the marginal ice zone (MIZ) and polynyas plays an important role for phytoplankton productivity and krill abundance. Therefore mapping their spatial extent, seasonal and interannual variability is essential for understanding how current and future changes in these biological active regions may impact the Antarctic marine ecosystem. Knowledge of the distribution of different ice types to the total Antarctic sea ice cover may also help to shed light on the factors contributing towards recent expansion of the Antarctic ice cover in some regions and contraction in others. The long-term passive microwave satellite data record provides the longest and most consistent data record for assessing different ice types. However, estimates of the amount of MIZ, consolidated pack ice and polynyas depends strongly on what sea ice algorithm is used. This study uses two popular passive microwave sea ice algorithms, the NASA Team and Bootstrap to evaluate the distribution and variability in the MIZ, the consolidated pack ice and coastal polynyas. Results reveal the NASA Team algorithm has on average twice the MIZ and half the consolidated pack ice area as the Bootstrap algorithm. Polynya area is also larger in the NASA Team algorithm, and the timing of maximum polynya area may differ by as much as 5 months between algorithms. These differences lead to different relationships between sea ice characteristics and biological processes, as illustrated here with the breeding success of an Antarctic seabird.

  18. Antarctic teleost immunoglobulins: more extreme, more interesting.

    Coscia, Maria Rosaria; Varriale, Sonia; Giacomelli, Stefano; Oreste, Umberto

    2011-11-01

    We have investigated the immunoglobulin molecule and the genes encoding it in teleosts living in the Antarctic seas at the constant temperature of -1.86 °C. The majority of Antarctic teleosts belong to the suborder Notothenioidei (Perciformes), which includes only a few non-Antarctic species. Twenty-one Antarctic and two non-Antarctic Notothenioid species were included in our studies. We sequenced immunoglobulin light chains in two species and μ heavy chains, partially or totally, in twenty species. In the case of heavy chain, genomic DNA and the cDNA encoding the secreted and the membrane form were analyzed. From one species, Trematomus bernacchii, a spleen cDNA library was constructed to evaluate the diversity of VH gene segments. T. bernacchii IgM, purified from the serum and bile, was characterized. Homology Modelling and Molecular Dynamics were used to determine the molecular structure of T. bernacchii and Chionodraco hamatus immunoglobulin domains. This paper sums up the previous results and broadens them with the addition of unpublished data.

  19. Antarctic station life: The first 15 years of mixed expeditions to the Antarctic

    Sarris, Aspa

    2017-02-01

    This study examined the experiences of women who lived and worked on remote and isolated Antarctic stations for up to 15 months at a time. The study employed purposeful sampling and a longitudinal - processual approach to study women's experiences over the first 15 years of mixed gender Antarctic expeditions. The retrospective analysis was based on a semi-structured interview administered to 14 women upon their return to Australia. The results showed that women referred to the natural physical Antarctic environment as one of the best aspects of their experience and the reason they would recommend the Antarctic to their friends as a good place to work. In describing the worst aspect of their experience, women referred to aspects of Antarctic station life, including: (i) the male dominated nature of station culture; (ii) the impact of interpersonal conflict, including gender based conflict and friction between scientists and trades workers; and (iii) the lack of anonymity associated with living and working with the same group of individuals, mainly men, for up to 12 months or more. The results are discussed within the context of the evolution of Antarctic station culture and recommendations are made in terms of the demography of expeditions, expeditioner selection and recruitment and the ongoing monitoring of Antarctic station culture. The study presents a framework that can be applied to groups and teams living and working in analogous isolated, confined and extreme work environments, including outer space missions.

  20. 76 FR 9849 - Comprehensive Environmental Evaluations for Antarctic Activities

    2011-02-22

    .... SUPPLEMENTARY INFORMATION: Article 3 of Annex I to the Protocol on Environmental Protection to the Antarctic Treaty requires the preparation of a CEE for any proposed Antarctic activity likely to have more than a... Comprehensive Environmental Evaluations for Antarctic Activities SUMMARY: The Department of State gives...

  1. Semi-empirical models for chlorine activation and ozone depletion in the Antarctic stratosphere: proof of concept

    Huck, P. E.; Bodeker, G. E.; Kremser, S.; McDonald, A. J.; Rex, M.; Struthers, H.

    2013-03-01

    Two semi-empirical models were developed for the Antarctic stratosphere to relate the shift of species within total chlorine (Cly = HCl + ClONO2 + HOCl + 2 × Cl2 + 2×Cl2O2 + ClO + Cl) into the active forms (here: ClOx = 2×Cl2O2 + ClO), and to relate the rate of ozone destruction to ClOx. These two models provide a fast and computationally inexpensive way to describe the inter- and intra-annual evolution of ClOx and ozone mass deficit (OMD) in the Antarctic spring. The models are based on the underlying physics/chemistry of the system and capture the key chemical and physical processes in the Antarctic stratosphere that determine the interaction between climate change and Antarctic ozone depletion. They were developed considering bulk effects of chemical mechanisms for the duration of the Antarctic vortex period and quantities averaged over the vortex area. The model equations were regressed against observations of daytime ClO and OMD providing a set of empirical fit coefficients. Both semi-empirical models are able to explain much of the intra- and inter-annual variability observed in daily ClOx and OMD time series. This proof-of-concept paper outlines the semi-empirical approach to describing the evolution of Antarctic chlorine activation and ozone depletion.

  2. Semi-empirical models for chlorine activation and ozone depletion in the Antarctic stratosphere: proof of concept

    P. E. Huck

    2013-03-01

    Full Text Available Two semi-empirical models were developed for the Antarctic stratosphere to relate the shift of species within total chlorine (Cly = HCl + ClONO2 + HOCl + 2 × Cl2 + 2×Cl2O2 + ClO + Cl into the active forms (here: ClOx = 2×Cl2O2 + ClO, and to relate the rate of ozone destruction to ClOx. These two models provide a fast and computationally inexpensive way to describe the inter- and intra-annual evolution of ClOx and ozone mass deficit (OMD in the Antarctic spring. The models are based on the underlying physics/chemistry of the system and capture the key chemical and physical processes in the Antarctic stratosphere that determine the interaction between climate change and Antarctic ozone depletion. They were developed considering bulk effects of chemical mechanisms for the duration of the Antarctic vortex period and quantities averaged over the vortex area. The model equations were regressed against observations of daytime ClO and OMD providing a set of empirical fit coefficients. Both semi-empirical models are able to explain much of the intra- and inter-annual variability observed in daily ClOx and OMD time series. This proof-of-concept paper outlines the semi-empirical approach to describing the evolution of Antarctic chlorine activation and ozone depletion.

  3. Fluxes of microbes, organic aerosols, dust, and methanesulfonate onto Greenland and Antarctic ice

    P. B. Price

    2008-12-01

    Full Text Available Using a spectrofluorimeter with 224-nm laser excitation to measure fluorescence intensity at 300-μm depth intervals, we report results of the first comparative study of concentrations of microbial cells (using the spectrum of protein-bound tryptophan (Trp as a proxy and of aerosols with an autofluorescence spectrum different from Trp as a function of depth in ice cores from west Antarctica (WAIS Divide and Siple Dome and Greenland (GISP 2. The ratio of fluxes of microbial cells onto Antarctic Greenland ice is 0.23±0.11 and of non-Trp aerosols is 0.17±0.08, both of which are comparable to the ratio of fluxes of mineral dust at Antarctic and Greenland sites (0.09±0.06. In contrast, the ratio of fluxes of methanesulfonate (MSA onto Antarctic relative to Greenland sites is 1.86±0.4, a factor 20 higher. The lower fluxes of microbes, non-Trp aerosols, and dust onto Antarctic ice may be due to the smaller areas of their source regions, together with less favorable wind patterns for Antarctic ice than Greenland ice. We attribute the higher fluxes of MSA in Antarctic ice to the concentration of haptophytes, a phylum of marine algae, in the far more extensive sea ice margin around Antarctica than around Greenland. The similarity of flux ratios of microbes and non-Trp aerosols to dust flux ratios suggests that their source regions overlap with dust sources rather than with MSA sources. A new version of the spectrofluorimeter with additional channels for mapping chlorophyll and volcanic tephra will be used to map WAIS Divide ice at 1 mm intervals to bedrock.

  4. Fluxes of microbes, organic aerosols, dust, and methanesulfonate onto Greenland and Antarctic ice

    Price, P. B.; Rohde, R. A.; Bay, R. C.

    2008-12-01

    Using a spectrofluorimeter with 224-nm laser excitation to measure fluorescence intensity at 300-μm depth intervals, we report results of the first comparative study of concentrations of microbial cells (using the spectrum of protein-bound tryptophan (Trp) as a proxy) and of aerosols with an autofluorescence spectrum different from Trp as a function of depth in ice cores from west Antarctica (WAIS Divide and Siple Dome) and Greenland (GISP 2). The ratio of fluxes of microbial cells onto Antarctic Greenland ice is 0.23±0.11 and of non-Trp aerosols is 0.17±0.08, both of which are comparable to the ratio of fluxes of mineral dust at Antarctic and Greenland sites (0.09±0.06). In contrast, the ratio of fluxes of methanesulfonate (MSA) onto Antarctic relative to Greenland sites is 1.86±0.4, a factor 20 higher. The lower fluxes of microbes, non-Trp aerosols, and dust onto Antarctic ice may be due to the smaller areas of their source regions, together with less favorable wind patterns for Antarctic ice than Greenland ice. We attribute the higher fluxes of MSA in Antarctic ice to the concentration of haptophytes, a phylum of marine algae, in the far more extensive sea ice margin around Antarctica than around Greenland. The similarity of flux ratios of microbes and non-Trp aerosols to dust flux ratios suggests that their source regions overlap with dust sources rather than with MSA sources. A new version of the spectrofluorimeter with additional channels for mapping chlorophyll and volcanic tephra will be used to map WAIS Divide ice at 1 mm intervals to bedrock.

  5. Improvement parameters in dynamic compaction adjacent to the slopes

    Elham Ghanbari; Amir Hamidi

    2015-01-01

    Dynamic compaction is a cost-effective method commonly used for improvement of sandy soils. A number of researchers have investigated experimentally and numerically the improvement parameters of soils using dynamic compaction, such as crater depth, improvement depth, and radial improvement, however, these parameters are not studied for improvement adjacent to the slopes or trenches. In this research, four different slopes with different inclinations are modeled numerically using the finite element code ABAQUS, and impact loads of dynamic compaction are applied. The static factors of safety are kept similar for all trenches and determined numerically by application of gravity loads to the slope using strength reduction method (SRM). The analysis focuses on crater depth and improvement region which are compared to the state of flat ground. It can be observed that compacted area adjacent to the slopes is narrower and slightly away from the slope compared to the flat state. Moreover, crater depth increases with increase in slope inclination.

  6. Antarctic “quiet” site stirs debate

    Simarski, Lynn Teo

    Geophysicists from the United States and New Zealand plan to meet in the coming months to assess the electromagnetic pollution of an Antarctic site especially designated for research. U.S. scientists charge that a satellite Earth station erected apparently inside the preserve by New Zealand's Telecom company could interfere with experiments on the ionosphere and magnetosphere (Eos, April 28, 1992). The Site of Special Scientific Interest at Arrival Heights, the only Antarctic preserve specifically for physical science, is located near the U.S. McMurdo and New Zealand Scott bases.Debate over the Telecom facility inter-twines diplomatic and scientific issues. One question is whether the station violates the Antarctic treaty. Secondly, does it actually impair research at the site—or could it harm future experiments? To deepen the imbroglio, those involved from both nations say that transmissions from sources off-site also interfere with research—raising doubts about how pristine the site really is.

  7. NSF's role in Antarctic environment scrutinized

    Bush, Susan

    In the last few years, the National Science Foundation has come under criticism by environmental groups for inadequate stewardship in the U.S. Antarctic Program's environmental issues. Since 1978, NSF was given full responsibility, by Executive Order, for budgeting and managing the entire U.S. national program in Antarctica, including logistics support. NSF has also been responsible for the compliance of the U.S. Antarctic Program with environmental protection measures agreed to by the Antarctic Treaty nations. Specifically under fire by environmentalists have been NSF's maintenance of a land-fill, open-air burning of solid waste, and the removal of toxic substances. According to Peter E. Wilkniss, director of the Division of Polar Programs at NSF, open burning is no longer taking place and will not be allowed in the future.

  8. Iron biogeochemistry in Antarctic pack ice during SIPEX-2

    Lannuzel, Delphine; Chever, Fanny; van der Merwe, Pier C.; Janssens, Julie; Roukaerts, Arnout; Cavagna, Anne-Julie; Townsend, Ashley T.; Bowie, Andrew R.; Meiners, Klaus M.

    2016-09-01

    Our study quantified the spatial and temporal distribution of Fe and ancillary biogeochemical parameters at six stations visited during an interdisciplinary Australian Antarctic marine science voyage (SIPEX-2) within the East Antarctic first-year pack ice zone during September-October 2012. Unlike previous studies in the area, the sea ice Chlorophyll a, Particulate Organic Carbon and Nitrogen (POC and PON) maxima did not occur at the ice/water interface because of the snow loading and dynamic processes under which the sea ice formed. Iron in sea ice ranged from 0.9 to 17.4 nM for the dissolved (0.2 μm) fraction. Our results highlight that the concentration of particulate Fe in sea ice was highest when approaching the continent. The high POC concentration and high particulate iron to aluminium ratio in sea ice samples demonstrate that 71% of the particulate Fe was biogenic in composition. Our estimated Fe flux from melting pack ice to East Antarctic surface waters over a 30 day melting period was 0.2 μmol/m2/d of DFe, 2.7 μmol/m2/d of biogenic PFe and 1.3 μmol/m2/d of lithogenic PFe. These estimates suggest that the fertilization potential of the particulate fraction of Fe may have been previously underestimated due to the assumption that it is primarily lithogenic in composition. Our new measurements and calculated fluxes indicate that a large fraction of the total Fe pool within sea ice may be bioavailable and therefore, effective in promoting primary productivity in the marginal ice zone.

  9. Spatial-temporal Distribution and Hazard Grading of Red Tide and Variation of Red-tide Species in Qingdao Adjacent Sea Area%青岛近海赤潮灾害分级与时空分布及赤潮生物的变化

    刘霜; 张继民; 张洪亮; 李钦亮; 崔文林

    2014-01-01

    根据赤潮发生面积和赤潮藻类的危害类型,将青岛近海发生的赤潮划分为特大、重度、中度、轻度和轻微共计5个灾害级别。结果表明,1990-2013年青岛近海共计发生赤潮33次,以轻微灾害和轻度灾害为主,其它级别尚未发生;其中,发生面积小于10 km2赤潮占总数的51.5%,60.6%的赤潮由基本无害的赤潮种类引起,发生范围以胶州湾和浮山湾近海为主;赤潮次数和面积基本呈现4~5年的波动周期,高发期集中在每年的6-8月;主要赤潮生物种类是红色中缢虫(Mesodinium rubrum)和夜光虫(Noctiluca scintillans);引发赤潮的生物种类逐渐增多,甲藻比例升高,罕见种类逐渐出现。赤潮种类的变化反映出青岛近海浮游植物的种类组成发生了改变,与期间青岛近岸海洋环境的变化密切相关。%Red tides occurred in Qingdao adjacent sea area were classified into five levels,i,e.,extra large, large,moderate,mild and slight,according to the red tide scales and hazard types.Thirty-three red tide events were recorded from 1990 to 2013 with the main types of slight red tide and mild red tide.Among them,the scale of red tides was less than 10 km2 accounting for 5 1 .5%of the total red tides and 60.6%of the red tides were caused by harmless red tide species.Jiaozhou Bay and Fushan Bay adjacent sea area were the red tide-frequent-occurrence areas.The frequencies and scales of red tides peaked every four to five years from June to August,with the main red tide species of Mesodinium rubrum and Noctiluca scintillans.The species of red tide gradually increased with a rising tendency of Pyrrophyta occurrence frequency,even rare species have appeared in the past few years.The changes of the red tide species indicated that the species composition of phytoplankton in Qingdao inshore area has changed,which is closely related to the marine environment of Qingdao near-shore areas.

  10. Determinants of adjacency matrices of graphs

    Alireza Abdollahi

    2012-12-01

    Full Text Available We study the set of all determinants of adjacency matrices of graphs with a given number of vertices. Using Brendan McKay's data base of small graphs, determinants of graphs with at most $9$ vertices are computed so that the number of non-isomorphic graphs with given vertices whose determinants are all equal to a number is exhibited in a table. Using an idea of M. Newman, it is proved that if $G$ is a graph with $n$ vertices and ${d_1,dots,d_n}$ is the set of vertex degrees of $G$, then $gcd(2m,d^2$ divides the determinant of the adjacency matrix of $G$, where $d=gcd(d_1,dots,d_n$. Possible determinants of adjacency matrices of graphs with exactly two cycles are obtained.

  11. Mysterious iodine-overabundance in Antarctic meteorites

    Dreibus, G.; Waenke, H.; Schultz, L.

    1986-01-01

    Halogen as well as other trace element concentrations in meteorite finds can be influenced by alteration processes on the Earth's surface. The discovery of Antarctic meteorites offered the opportunity to study meteorites which were kept in one of the most sterile environment of the Earth. Halogen determination in Antartic meteorites was compared with non-Antarctic meteorites. No correlation was found between iodine concentration and the weathering index, or terrestrial age. The halogen measurements indicate a contaminating phase rich in iodine and also containing chlorine. Possible sources for this contamination are discussed.

  12. Geodetic implications on block formation and geodynamic domains in the South Shetland Islands, Antarctic Peninsula

    Berrocoso, M.; Fernández-Ros, A.; Prates, G.; García, A.; Kraus, S.

    2016-01-01

    The South Shetland Islands archipelago is dynamically complex due to its tectonic surroundings. Most islands are part of a formerly active volcanic arc, although Deception, Penguin and Bridgeman Islands, as well as several submarine volcanoes, are characterized by active back-arc volcanism. Geodetic benchmarks were deployed and the movement of the lithosphere to which they were fixed measured to provide geodynamic insight for the South Shetland Islands, Bransfield Basin and Antarctic Peninsula area based on surface deformation. These benchmarks' data add spatial and temporal coverage to previous results. The results reveal two different geodynamic patterns, each confined to a distinct part of the South Shetland Islands archipelago. The inferred absolute horizontal velocity vectors for the benchmarks in the northeastern part of the archipelago are consistent with the opening of the Bransfield Basin, while benchmark vectors in the southwestern part of the archipelago are similar to those of the benchmarks on the Antarctic Peninsula. In between, Snow, Deception and Livingston Islands represent a transition zone. In this area, the horizontal velocity vectors relative to the Antarctic plate shift northeastwards from N to NW. Furthermore, the South Shetland Islands benchmarks, except for that at Gibbs (Elephant) Islands, indicate subsidence, which might be a consequence of the slab roll-back at the South Shetland Trench. In contrast, the uplift revealed by the Antarctic Peninsula benchmarks suggests glacial isostatic adjustment after the Larson B ice-shelf breakup.

  13. Application of Multispectral Satellite Data for Geological Mapping in Antarctic Environments

    Pour, A. B.; Hashim, M.; Hong, J. K.

    2016-09-01

    Remote sensing imagery is capable to provide a solution to overcome the difficulties associated with geological field mapping in the Antarctic. Advanced optical and radar satellite imagery is the most applicable tool for mapping and identification of inaccessible regions in Antarctic. Consequently, an improved scientific research using remote sensing technology would be essential to provide new and more complete lithological and structural data to fill the numerous knowledge gaps on Antarctica's geology. In this investigation, Oscar coast area in Graham Land, Antarctic Peninsula (AP) was selected to conduct a remote sensing study using Landsat-7 Thematic Mapper (TM), Landsat-8 and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data. Contrast-enhanced Red-Green-Blue (RGB) composites, band ratios and Relative Band Depth (RBD) image processing techniques were applied to Landsat-8 and ASTER dataset for establishing the spectral separation of the main lithologic groups exposed in the study area. The outcomes of this investigation demonstrated the applications of SWIR and TIR bands of the multispectral remote sensing datasets to identify lithological units and producing geological maps with suitable accuracy of ice-free rock regions in the Antarctic Peninsula. The results could be extended to map coverage of non-investigated regions further east and validated previously inferred geological observations concerning other rocks and mineral deposits throughout the Antarctica.

  14. APPLICATION OF MULTISPECTRAL SATELLITE DATA FOR GEOLOGICAL MAPPING IN ANTARCTIC ENVIRONMENTS

    A. B. Pour

    2016-09-01

    Full Text Available Remote sensing imagery is capable to provide a solution to overcome the difficulties associated with geological field mapping in the Antarctic. Advanced optical and radar satellite imagery is the most applicable tool for mapping and identification of inaccessible regions in Antarctic. Consequently, an improved scientific research using remote sensing technology would be essential to provide new and more complete lithological and structural data to fill the numerous knowledge gaps on Antarctica’s geology. In this investigation, Oscar coast area in Graham Land, Antarctic Peninsula (AP was selected to conduct a remote sensing study using Landsat-7 Thematic Mapper (TM, Landsat-8 and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER data. Contrast-enhanced Red-Green-Blue (RGB composites, band ratios and Relative Band Depth (RBD image processing techniques were applied to Landsat-8 and ASTER dataset for establishing the spectral separation of the main lithologic groups exposed in the study area. The outcomes of this investigation demonstrated the applications of SWIR and TIR bands of the multispectral remote sensing datasets to identify lithological units and producing geological maps with suitable accuracy of ice-free rock regions in the Antarctic Peninsula. The results could be extended to map coverage of non-investigated regions further east and validated previously inferred geological observations concerning other rocks and mineral deposits throughout the Antarctica.

  15. TECTONIC EVOLUTION AND PALEOCONTINENT RECONSTRUCYION OF QINGHAI-TIBET PLATEAU AND ITS ADJACENT AREA SINCE THE LATE PALEOZOIC%青藏高原及其邻区晚古生代以来构造演化与古大陆再造

    冯岩; 温珍河; 侯方辉; 高志清; 祁江豪

    2013-01-01

    基于近年来在中国西藏及邻区所取得的古地磁成果,结合相关古生物、岩石学、沉积学和构造变形等方面资料,定量地讨论了西藏地区几个块体间的相对位置和相对运动关系,块体的分离和拼合时代.羌塘块体晚石炭世开始快速向北漂移,在晚二叠—早三叠世增生到古亚洲大陆上;冈底斯块体在晚三叠世从冈瓦纳大陆分离出来,在早 晚白垩世同羌塘块体碰撞;喜马拉雅块体晚侏罗世开始脱离冈瓦纳大陆,晚白垩世随着印度洋的快速扩张开始发生大幅度北移,在晚白垩世古近与冈底斯块体碰撞.%Based on the paleomagnetic data from Tibet and adjacent areas,and the studies on paleogeogra-phy,petrlogy,sedimentology and tectonic deformation,we quantitatively reconstructed the relative position and relative0 motion of the blocks in Tibet area. The Qiangtang block began to drift northwards rapidly in Late Carboniferous,and collided with the ancient Asian continent during Late Permian to Early Triassic. The Gangdise block separated from the Gondwana continent in late Triassic,and collided with the Qiangtang block during Early-Late Cretaceous. The Himalayan block separated from the Gondwana continent in Late Jurassic, and began to drift northwards rapidly in Late Cretaceous, and collided with the Gangdise block during Late Cretaceous to Early Tertiary.

  16. Levantamento florístico das macroalgas da baía de Sepetiba e adjacências, RJ: ponto de partida para o Programa GloBallast no Brasil Floristic survey of the macroalgae from Sepetiba bay and surrounding area, Rio de Janeiro State: starting point for the GloBallast Programme in Brazil

    Maria Teresa Menezes de Széchy

    2005-09-01

    amostragem, em estudos futuros. Recomenda-se a padronização metodológica para o levantamento florístico de áreas portuárias como a baía de Sepetiba, e de outras áreas do litoral brasileiro sujeitas à interferência do homem, tomando por base o procedimento CRIMP.The Port of Sepetiba, State of Rio de Janeiro, was chosen as the Brazilian pilot area for the project "Global Ballast Water Management Programme" (GloBallast Programme. For comparative purposes, six countries were guided by the GloBallast Programme to follow the same methodology, emphasizing identification of organisms to the specific level during the preliminary biota survey. This study aimed to apply the methodology established by the Australian Centre for Research on Introduced Marine Pests (CRIMP procedures for the floristic survey of macroalgae of natural hard substrate of the area of Port of Sepetiba. Macroalgal samplings were carried out in November 2001 at nine sites situated in Sepetiba Bay and adjacent area, from the sublittoral fringe to ca. - 4 m deep. At each site, six 0.1 m² quadrates were scraped. Specimens were sent to the Herbarium of the "Instituto de Pesquisas Jardim Botânico do Rio de Janeiro" (RB. Ninety six species were identified (20 Chlorophyta, 16 Phaeophyta, and 60 Rhodophyta; 12 species have not been cited to the study area by the preceding studies. Cladophora pellucidoidea C. Hoek, Coelothrix irregularis (Harv. Boergesen, and Acrochaetium savianum (Menegh. Nägeli are recorded for the first time to the state of Rio de Janeiro. There are no evidences to conclude that the new records correspond to recently introduced species through the port activities. The methodological procedures proved to be efficient because they produced a species list to be comparable to those of taxonomic surveys with higher sampling effort. They also enlarged the existing information about the phycological flora of Sepetiba Bay. Nevertheless, for future studies, we point out the importance of a re

  17. Antarctic Data Management as Part of the IPY Legacy

    de Bruin, T.

    2006-12-01

    The Antarctic Treaty states that "scientific observations and results from Antarctica shall be exchanged and made freely available". Antarctica includes the Southern Ocean. In support of this, National Antarctic Data Centres (NADC) are being established to catalogue data sets and to provide information on data sets to scientists and others with interest in Antarctic science. The Joint Committee on Antarctic Data Management (JCADM) was established by the Scientific Committee on Antarctic Research (SCAR) and the Council of Managers of National Antarctic Programs (COMNAP). JCADM comprises representatives of the National Antarctic Data Centres. Currently 30 nations around the world are represented in JCADM. JCADM is responsible for the Antarctic Master Directory (AMD), the internationally accessible, web-based, searchable record of Antarctic and Southern Ocean data set descriptions. The AMD is directly integrated into the international Global Change Master Directory (GCMD) to help further merge Antarctic science into global science. The AMD is a resource for scientists to advertise the data they have collected and to search for data they may need. JCADM is the Antarctic component of the IPY Data Infrastructure, which is presently being developed. This presentation will give an overview of the organization of Antarctic and Southern Ocean data management with sections on the organizational structure of JCADM, contents of the Antarctic Master Directory, relationships to the SCAR Scientific Research Programmes (SRP) and IPY, international embedding and connections with discipline-based peer organizations like the International Oceanographic Data and Information Exchange Committee (IODE). It will focus primarily on the role that an existing infrastructure as JCADM, may play in the development of the IPY Data Infrastructure and will provide considerations for IPY data management, based on the experiences in Antarctic and oceanographic data management.

  18. Anti-inflammatory activity in selected Antarctic benthic organisms

    Juan eMoles

    2014-07-01

    Full Text Available Antarctic benthos was prospected in search for anti-inflammatory activity in polar benthic invertebrates, in two different geographical areas: deep-bottoms of the Eastern Weddell Sea and shallow-waters of the South Shetland Islands. A total of 36 benthic algae and invertebrate species were selected to perform solubility tests in order to test them for anti-inflammatory activity. From these, ethanol extracts of ten species from five different phyla resulted suitable to be studied in cell macrophage cultures (RAW 264.7. Cytotoxicity (MTT method and production of inflammatory mediators (prostaglandin E2, leukotriene B4, interleukin-1 were determined at three extract concentrations (50, 125, 250 g/mL. Bioassays resulted in four different species showing anti-inflammatory activity corresponding to three sponges: Mycale (Oxymycale acerata, Isodictya erinacea, and I. toxophila; and one hemichordate: Cephalodiscus sp. These results show that Antarctic sessile invertebrates may have great value as a source of lead compounds with potential pharmaceutical applications.

  19. Global dynamics of the Antarctic ice sheet

    Oerlemans, J.

    2002-01-01

    The total mass budget of the Antarctic ice sheet is studied with a simple axi-symmetrical model. The ice-sheet has a parabolic profile resting on a bed that slopes linearly downwards from the centre of the ice sheet into the ocean. The mean ice velocity at the grounding line is assumed to be proport

  20. Contrasts between Antarctic and Arctic ozone depletion.

    Solomon, Susan; Portmann, Robert W; Thompson, David W J

    2007-01-09

    This work surveys the depth and character of ozone depletion in the Antarctic and Arctic using available long balloon-borne and ground-based records that cover multiple decades from ground-based sites. Such data reveal changes in the range of ozone values including the extremes observed as polar air passes over the stations. Antarctic ozone observations reveal widespread and massive local depletion in the heart of the ozone "hole" region near 18 km, frequently exceeding 90%. Although some ozone losses are apparent in the Arctic during particular years, the depth of the ozone losses in the Arctic are considerably smaller, and their occurrence is far less frequent. Many Antarctic total integrated column ozone observations in spring since approximately the 1980s show values considerably below those ever observed in earlier decades. For the Arctic, there is evidence of some spring season depletion of total ozone at particular stations, but the changes are much less pronounced compared with the range of past data. Thus, the observations demonstrate that the widespread and deep ozone depletion that characterizes the Antarctic ozone hole is a unique feature on the planet.

  1. First stage of INTRAMAP: INtegrated Transantarctic Mountains and Ross Sea Area Magnetic Anomaly Project

    D. Damaske

    1999-06-01

    Full Text Available INTRAMAP (INtegrated Transantarctic Mountains and Ross Sea Area Magnetic Anomaly Project is an international effort to merge the magnetic data acquired throughout the "Ross Sea Antarctic Sector" (south of 60°S between 135°-255°E including the Transantarctic Mountains (TAM, the Ross Sea, Marie Byrd Land, and the Pacific coast, and also to begin the compilation efforts for new data over the Wilkes Basin. This project is a component of the continental scale Antarctic Digital Magnetic Anomaly Project (ADMAP. The first stage of INTRAMAP addresses the analysis and merging of GITARA (1991-1994 and GANOVEX (1984 aeromagnetic surveys together with ground magnetic data (1984-1989. The combined data sets cover an area of approximately 30 km2 over Victoria Land and adjacent Ross Sea. Map and profile gridding were implemented to integrate the data sets. These approaches are studied for improving existing strategies to adopt for the whole magnetic compilation effort. The final microlevelled grid that we produce is a new tool for regional interpretation of the main tectonic and geologic features of this sector of Antarctica.

  2. Assessment of Arctic and Antarctic sea ice predictability in CMIP5 decadal hindcasts

    Yang, Chao-Yuan; Liu, Jiping; Hu, Yongyun; Horton, Radley M.; Chen, Liqi; Cheng, Xiao

    2016-10-01

    This paper examines the ability of coupled global climate models to predict decadal variability of Arctic and Antarctic sea ice. We analyze decadal hindcasts/predictions of 11 Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Decadal hindcasts exhibit a large multi-model spread in the simulated sea ice extent, with some models deviating significantly from the observations as the predicted ice extent quickly drifts away from the initial constraint. The anomaly correlation analysis between the decadal hindcast and observed sea ice suggests that in the Arctic, for most models, the areas showing significant predictive skill become broader associated with increasing lead times. This area expansion is largely because nearly all the models are capable of predicting the observed decreasing Arctic sea ice cover. Sea ice extent in the North Pacific has better predictive skill than that in the North Atlantic (particularly at a lead time of 3-7 years), but there is a re-emerging predictive skill in the North Atlantic at a lead time of 6-8 years. In contrast to the Arctic, Antarctic sea ice decadal hindcasts do not show broad predictive skill at any timescales, and there is no obvious improvement linking the areal extent of significant predictive skill to lead time increase. This might be because nearly all the models predict a retreating Antarctic sea ice cover, opposite to the observations. For the Arctic, the predictive skill of the multi-model ensemble mean outperforms most models and the persistence prediction at longer timescales, which is not the case for the Antarctic. Overall, for the Arctic, initialized decadal hindcasts show improved predictive skill compared to uninitialized simulations, although this improvement is not present in the Antarctic.

  3. Neogene kinematic history of Nazca-Antarctic-Phoenix slab windows beneath Patagonia and the Antarctic Peninsula

    Breitsprecher, Katrin; Thorkelson, Derek J.

    2009-01-01

    The Patagonian slab window is a subsurface tectonic feature resulting from subduction of the Nazca-Antarctic spreading-ridge system (Chile Rise) beneath southern South America. The geometry of the slab window had not been rigorously defined, in part because of the complex nature of the history of ridge subduction in the southeast Pacific region, which includes four interrelated spreading-ridge systems since 20 Ma: first, the Nazca-Phoenix ridge beneath South America, then simultaneous subduction of the Nazca-Antarctic and the northern Phoenix-Antarctic spreading-ridge systems beneath South America, and the southern Phoenix-Antarctic spreading-ridge system beneath Antarctica. Spreading-ridge paleo-geographies and rotation poles for all relevant plate pairs (Nazca, Phoenix, Antarctic, South America) are available from 20 Ma onward, and form the mathematical basis of our kinematic reconstruction of the geometry of the Patagonia and Antarctic slab windows through Neogene time. At approximately 18 Ma, the Nazca-Phoenix-Antarctic oceanic (ridge-ridge-ridge) triple junction enters the South American trench; we recognize this condition as an unstable quadruple junction. Heat flow at this junction and for some distance beneath the forearc would be considerably higher than is generally recognized in cases of ridge subduction. From 16 Ma onward, the geometry of the Patagonia slab window developed from the subduction of the trailing arms of the former oceanic triple junction. The majority of the slab window's areal extent and geometry is controlled by the highly oblique (near-parallel) subduction angle of the Nazca-Antarctic ridge system, and by the high contrast in relative convergence rates between these two plates relative to South America. The very slow convergence rate of the Antarctic slab is manifested by the shallow levels achieved by the slab edge (< 45 km); thus no point on the Antarctic slab is sufficiently deep to generate "normal" mantle-derived arc-type magmas

  4. Contrasting patterns in lichen diversity in the continental and maritime Antarctic

    Singh, Shiv Mohan; Olech, Maria; Cannone, Nicoletta; Convey, Peter

    2015-09-01

    Systematic surveys of the lichen floras of Schirmacher Oasis (Queen Maud Land, continental Antarctic), Victoria Land (Ross Sector, continental Antarctic) and Admiralty Bay (South Shetland Islands, maritime Antarctic) were compared to help infer the major factors influencing patterns of diversity and biogeography in the three areas. Biogeographic patterns were determined using a variety of multivariate statistical tools. A total of 54 lichen species were documented from Schirmacher Oasis (SO), 48 from Victoria Land (VL) and 244 from Admiralty Bay (AB). Of these, 21 species were common to all areas. Most lichens from the SO and VL areas were microlichens, the dominant genus being Buellia. In AB, in contrast, many macrolichens were also present and the dominant genus was Caloplaca. In SO and VL large areas lacked any visible lichen cover, even where the ground was snow-free in summer. Small-scale diversity patterns were present in AB, where the number of species and genera was greater close to the coast. Most species recorded were rare in the study areas in which they were present and endemic to Antarctica.

  5. Cryptic species diversity in sub-Antarctic islands: A case study of Lepidonotothen.

    Dornburg, Alex; Federman, Sarah; Eytan, Ron I; Near, Thomas J

    2016-11-01

    The marine fauna of the Southern Ocean is well known for an impressive adaptive radiation of fishes, the notothenioids. However, when compared to other marine areas, the frigid waters of the Southern Ocean also contain a seemingly large proportion of cryptic species. The documented instances of speciation in the absence of morphological change are largely observed in invertebrate taxa, in particular around peri- and sub-Antarctic islands such as South Georgia, which has been dubbed a cryptic species hotspot. This prevalence of cryptic species raises the question of how generalizable these patterns are for Antarctic vertebrates. Here we examine aspects of genotype and phenotype in an Antarctic notothenioid fish species, Lepidonotothen nudifrons, which is distributed in near shore habitats of the Antarctic Peninsula, South Orkney Islands, South Georgia, and the South Sandwich Islands. The results of our analyses show that L. nudifrons comprises two species. We highlight that cryptic species are phenomena not restricted to invertebrate lineages, raising the possibility that the species diversity of notothenioids and other Southern Ocean fishes is under-described. In addition, our findings raise several questions about the evolutionary origin and maintenance of morphological stasis in one of the most extreme habitats on earth.

  6. Antarctic macrobenthic communities: A compilation of circumpolar information

    Julian Gutt

    2013-02-01

    Full Text Available Comprehensive information on Antarctic macrobenthic community structure has been publicly available since the 1960s. It stems from trawl, dredge, grab, and corer samples as well as from direct and camera observations (Table 1–2. The quality of this information varies considerably; it consists of pure descriptions, figures for presence (absence and abundance of some key taxa or proxies for such parameters, e.g. sea-floor cover. Some data sets even cover a defined and complete proportion of the macrobenthos with further analyses on diversity and zoogeography. As a consequence the acquisition of data from approximately 90 different campaigns assembled here was not standardised. Nevertheless, it was possible to classify this broad variety of known macrobenthic assemblages to the best of expert knowledge (Gutt 2007; Fig. 1. This overview does not replace statistically sound community and diversity analyses. However, it shows from where which kind of information is available and it acts as an example of the feasibility and power of such data collections. The data set provides unique georeferenced biological basic information for the planning of future coordinated research activities, e.g. under the umbrella of the biology program “Antarctic Thresholds - Ecosystem Resilience and Adaptation” (AnT-ERA of the Scientific Committee on Antarctic Research (SCAR and especially for actual conservation issues, e.g. the planning of Marine Protected Areas (MPAs by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR.

  7. Geophysical glimpses into the Ferrigno Rift at the northwestern tip of the West Antarctic Rift System

    Bingham, Robert; Ferraccioli, Fausto

    2014-05-01

    The West Antarctic Rift System (WARS) forms one of the largest continental rift systems on Earth. The WARS is of major significance as it forms the lithospheric cradle for the marine-based and potentially unstable West Antarctic Ice Sheet (WAIS). Seismic refraction, reflection, aeromagnetic, gravity and drilling in the Ross Sea have revealed most of what we know about its structure, tectonic and magmatic patterns and sedimentary basins. Aerogeophysical research and passive seismic networks have considerably extended our knowledge of the WARS and its influence on the overlying WAIS in the Siple Coast and Amundsen Sea Embayment (ASE) regions. The Bellingshausen Sea Embayment region has however remained largely unexplored, and hence the possible extent of the WARS in this sector has remained poorly constrained. Here we use a combination of reconnaissance ground-based and airborne radar observations, airborne gravity, satellite gravity and aeromagnetic data to investigate the WARS in the Bellingshausen Sea Embayment, in the area of the Ferrigno Ice Stream (Bingham et al., 2012, Nature). This region is of high significance, as it one of the main sectors of the WAIS that is currently exhibiting rapid ice loss, thought to be driven primarily by oceanic warming. Assessing geological controls on subice topography and ice dynamics is therefore of prime importance in this part of the WAIS. Ground-based and airborne radar image a subglacial basin beneath the Ferrigno Ice Stream that is up to 1.5 kilometres deep and that connects the ice-sheet interior to the Bellingshausen Sea margin. We interpret this basin as a narrow, glacially overdeepened rift basin that formed at the northwestern tip of the WARS. Satellite gravity data cannot resolve such a narrow rift basin but indicate that the crust beneath the region is likely thinned, lending support to the hypothesis that this area is indeed part of the WARS. Widely-spaced aeromagnetic data image a linear low along the inferred

  8. Adjacent Segment Pathology after Anterior Cervical Fusion.

    Chung, Jae Yoon; Park, Jong-Beom; Seo, Hyoung-Yeon; Kim, Sung Kyu

    2016-06-01

    Anterior cervical fusion has become a standard of care for numerous pathologic conditions of the cervical spine. However, subsequent development of clinically significant disc disease at levels adjacent to fused discs is a serious long-term complication of this procedure. As more patients live longer after surgery, it is foreseeable that adjacent segment pathology (ASP) will develop in increasing numbers of patients. Also, ASP has been studied more intensively with the recent popularity of motion preservation technologies like total disc arthroplasty. The true nature and scope of ASP remains poorly understood. The etiology of ASP is most likely multifactorial. Various factors including altered biomechanical stresses, surgical disruption of soft tissue and the natural history of cervical disc disease contribute to the development of ASP. General factors associated with disc degeneration including gender, age, smoking and sports may play a role in the development of ASP. Postoperative sagittal alignment and type of surgery are also considered potential causes of ASP. Therefore, a spine surgeon must be particularly careful to avoid unnecessary disruption of the musculoligamentous structures, reduced risk of direct injury to the disc during dissection and maintain a safe margin between the plate edge and adjacent vertebrae during anterior cervical fusion.

  9. Enteroenteroanastomosis near adjacent ileocecal valve in infants

    Wei-Wei Jiang; Xiao-Qun Xu; Qi-Ming Geng; Jie Zhang; Huan Chen; Xiao-Feng Lv; Chang-Gui Lu

    2012-01-01

    AIM:To investigate the feasibility and the effectiveness of ileoileostomy in the region adjacent to the ileocecal valve,which can retain the ileocecal valve in infants.METHODS:This is a retrospective review of 48 patients who underwent ileoileostomy in the region adjacent to the ileocecal valve (group 1) and 34 patients who underwent ileocecal resections and ileotransversanastomosis (group 2).Patients were monitored for the time to flatus,resumption of eating,length of hospital stay after surgery,serum total bile acid,vitamin B12 and postoperative complications.RESULTS:The time to flatus,time until resumption of eating and post-operative length of hospital stay showed no statistically significant differences between the two groups.Serum total bile acid and vitamin B12 were not significantly different between the two groups at post-operative day 1 and day 3,but were significantly decreased at 1 wk after operation in group 2.None of the patients died or suffered from stomal leak in these two groups.However,the incidence of diarrhea,intestinal infection,disturbance of acid-base balance and water-electrolytes in group 1 was lower than in group 2.CONCLUSION:Ileoileostomy in the region adjacent to the ileocecal valve is safe and results in fewer complications than ileotransversanastomosis in infants.

  10. 2010年春季长江口邻近海区水体中溶解有机碳、氮的分布特征及其影响因素%Dissolved organic carbon and nitrogen in Changjiang Estuary and adjacent sea areas in spring

    张述伟; 王江涛; 李宁; 阎雪姣

    2013-01-01

    The concentrations and distributions of dissolved organic carbon (DOC) and organic nitrogen ( DON) as well as their relationships with salinity,Chlorophyll,and AOU in the Changjiang Estuary and adjacent sea areas in May 2010 were analyzed. The average concentrations of DOC in surface and bottom water in our study area were 100 and 82 μmol/L, respectively. The average concentrations of DON in surface and bottom water were 20.2 and 15.5 μmol/L, respectively. The characteristics of distributions of DOC and DON were both higher near the coast and lower in outer sea, while the distribution of C/N was contrary. As to vertical distribution, the concentration of DOC and DON in surface waters was higher than that in bottom water. The relationships between DOC, DON and salinity Chlorophyll, and AOU showed that the terrestrial input was the main factor influencing the distribution of DOC and DON, while biological activities play the important part.%根据2010年5月在长江口邻近海区的调查,分析研究了海域溶解有机碳(DOC)和溶解有机氮(DON)的含量及其分布状况,并分别对DOC、DON与盐度(S)、叶绿素(Chla)、表观耗氧量(AOU)等要素的关系进行了初步探讨.结果表明,春季研究海域表、底层DOC平均含量分别为100 μmol/L和82 μmol/L,水平分布趋势均为近岸高于远岸,长江口附近DOC的浓度最高.DON的表、底层含量分别为20.2 μmol/L和15.5 μmol/L,水平分布特点与DOC类似,表现为近岸浓度高,远岸浓度低.垂直分布特点都是表层浓度高于底层.C/N分布与盐度相似,呈现近岸低于远岸的特征.研究海域DOC、DON与盐度和Chla的关系表明,其分布受陆源输入的影响较大,同时受一定的生物活动的影响.

  11. Resource Limitations on Soil Microbial Activity in an Antarctic Dry Valley

    Sparrow, Asley; Gregorich, Ed; Hopkins, David

    2011-01-01

    Although Antarctic dry valley soils function under some of the harshest environmental conditions on the planet, there is significant biological activity concentrated in small areas in the landscape. These productive areas serve as a source of C and N in organic matter redistributed to the surroun......Although Antarctic dry valley soils function under some of the harshest environmental conditions on the planet, there is significant biological activity concentrated in small areas in the landscape. These productive areas serve as a source of C and N in organic matter redistributed...... to the surrounding biologically impoverished soils. We conducted a 3-yr replicated field experiment involving soil amendment with C and N in simple (glucose and NH4Cl) and complex (glycine and lacustrine detritus) forms to evaluate the resource limitations on soil microbial activity in an Antarctic dry valley....... The respiratory response for all substrates was slow, with a significant but weak response to NH4Cl, followed by a more widespread response to all substrates after 2 yr and in laboratory incubations conducted 3 yr after substrate addition. This response suggests that the soil microbial community is N limited and...

  12. Exploration of Antarctic Subglacial environments: a challenge for analytical chemistry

    Traversi, R.; Becagli, S.; Castellano, E.; Ghedini, C.; Marino, F.; Rugi, F.; Severi, M.; Udisti, R.

    2009-12-01

    The large number of subglacial lakes detected in the Dome C area in East Antarctica suggests that this region may be a valuable source of paleo-records essential for understanding the evolution of the Antarctic ice cap and climate changes in the last several millions years. In the framework of the Project on “Exploration and characterization of Concordia Lake, Antarctica”, supported by Italian Program for Antarctic Research (PNRA), a glaciological investigation of the Dome C “Lake District” are planned. Indeed, the glacio-chemical characterisation of the ice column over subglacial lakes will allow to evaluate the fluxes of major and trace chemical species along the ice column and in the accreted ice and, consequently, the availability of nutrients and oligo-elements for possible biological activity in the lake water and sediments. Melting and freezing at the base of the ice sheet should be able to deliver carbon and salts to the lake, as observed for the Vostok subglacial lake, which are thought to be able to support a low concentration of micro-organisms for extended periods of time. Thus, this investigation represents the first step for exploring the subglacial environments including sampling and analysis of accreted ice, lake water and sediments. In order to perform reliable analytical measurements, especially of trace chemical species, clean sub-sampling and analytical techniques are required. For this purpose, the techniques already used by the CHIMPAC laboratory (Florence University) in the framework of international Antarctic drilling Projects (EPICA - European Project for Ice Coring in Antarctica, TALDICE - TALos Dome ICE core, ANDRILL MIS - ANTarctic DRILLing McMurdo Ice Shelf) were optimised and new techniques were developed to ensure a safe sample handling. CHIMPAC laboratory has been involved since several years in the study of Antarctic continent, primarily focused on understanding the bio-geo-chemical cycles of chemical markers and the

  13. The association of Antarctic krill Euphausia superba with the under-ice habitat.

    Hauke Flores

    Full Text Available The association of Antarctic krill Euphausia superba with the under-ice habitat was investigated in the Lazarev Sea (Southern Ocean during austral summer, autumn and winter. Data were obtained using novel Surface and Under Ice Trawls (SUIT, which sampled the 0-2 m surface layer both under sea ice and in open water. Average surface layer densities ranged between 0.8 individuals m(-2 in summer and autumn, and 2.7 individuals m(-2 in winter. In summer, under-ice densities of Antarctic krill were significantly higher than in open waters. In autumn, the opposite pattern was observed. Under winter sea ice, densities were often low, but repeatedly far exceeded summer and autumn maxima. Statistical models showed that during summer high densities of Antarctic krill in the 0-2 m layer were associated with high ice coverage and shallow mixed layer depths, among other factors. In autumn and winter, density was related to hydrographical parameters. Average under-ice densities from the 0-2 m layer were higher than corresponding values from the 0-200 m layer collected with Rectangular Midwater Trawls (RMT in summer. In winter, under-ice densities far surpassed maximum 0-200 m densities on several occasions. This indicates that the importance of the ice-water interface layer may be under-estimated by the pelagic nets and sonars commonly used to estimate the population size of Antarctic krill for management purposes, due to their limited ability to sample this habitat. Our results provide evidence for an almost year-round association of Antarctic krill with the under-ice habitat, hundreds of kilometres into the ice-covered area of the Lazarev Sea. Local concentrations of postlarval Antarctic krill under winter sea ice suggest that sea ice biota are important for their winter survival. These findings emphasise the susceptibility of an ecological key species to changing sea ice habitats, suggesting potential ramifications on Antarctic ecosystems induced by climate

  14. Direct linking of Greenland and Antarctic ice cores at the Toba eruption (74 kyr BP

    A. Svensson

    2012-11-01

    Full Text Available The Toba eruption that occurred some 74 kyr ago in Sumatra, Indonesia, is among the largest volcanic events on Earth over the last 2 million years. Tephra from this eruption has been spread over vast areas in Asia where it constitutes a major time marker close to the Marine Isotope Stage 4/5 boundary. As yet, no tephra associated with Toba has been identified in Greenland or Antarctic ice cores. Based on new accurate dating of Toba tephra from Malaysia and on accurately dated European stalagmites the Toba event is known to occur between the onsets of Greenland Interstadials (GI 19 and 20. Furthermore, the existing linking of Greenland and Antarctic ice cores by gas records and by the bipolar seesaw hypothesis suggests that the Antarctic counterpart is situated between Antarctic Isotope Maxima (AIM 19 and 20.

    In this work we suggest a direct synchronization of Greenland (NGRIP and Antarctic (EDML ice cores at the Toba eruption based on matching of a pattern of bipolar volcanic spikes. Annual layer counting between volcanic spikes in both cores allows for a unique match. We first demonstrate this bipolar matching technique at the already synchronized Laschamp geomagnetic excursion (41 kyr BP before we apply it to the suggested Toba interval. The Toba synchronization pattern covers some 2000 yr in GI-20 and AIM 19/20 and includes nine acidity peaks that are recognized in both ice cores.

    The suggested bipolar Toba synchronization has decadal precision. It thus allows a determination of the exact phasing of inter-hemispheric climate in a time interval of poorly constrained ice core records, and it allows for a discussion of the climatic impact of the Toba eruption in a global perspective. Furthermore, our bipolar match provides a way to place paleo-environmental records other than ice cores into a precise climatic context.

  15. Spatial distribution and characteristics of permafrost in Hurd Peninsula, Livingston Island, Maritime Antarctic

    Vieira, G.; Ramos, M.; Trindade, A.; Gruber, S.; Hauck, C.; Mora, C.; Batista, V.; Neves, M.; Pimpirev, C.; Kenderova, R.

    2009-04-01

    The Antarctic Peninsula is one of Earth's regions experiencing a faster increase on temperatures, with Mean Annual Air Temperatures (MAAT) rising ca. 2.5 °C in the last 50 years. The northerly location of the Antarctic Peninsula in respect to the Antarctic and its oceanic setting originate a milder and moister climate than in the Antarctic continent. The Northern Antarctic Peninsula is roughly located between the isotherms of MAAT of -1 °C to -8 °C at sea-level and therefore the northern tip and especially the South Shetlands are close to the limits of permafrost occurrence. If the observed warming trend is to continue in the near future, the region might suffer widespread permafrost degradation. Research on the permafrost environment of Hurd Peninsula has been taking place with systematical measurements by our group since January 2000 and currently we are able to provide a good overview of the spatial distribution and characteristics of permafrost terrain in Hurd Peninsula. Our research is based on shallow boreholes (Collado Ramos (115m). In 2006 Electrical Tomography Resistivity and refraction seismic profiles have been performed, providing us with a good overview of the general conditions of the permafrost terrain in the area. Air temperatures are measured at different sites accounting for altitude since a few years and during 3 summer campaigns the radiation balance was monitored continuously at two sites. Detailed geomorphological mapping of periglacial features has been conducted at a scale 1:5,000 providing important information about the geomorphological dynamics. Using the data gathered since 2000 it is now possible to present the general characteristics of the permafrost distribution in Hurd Peninsula as a first step towards a more comprehensive approach that is now starting that involves empirico-statistical modeling, remote sensing, as well as downscaling of mesoscale climate data.

  16. Searching for eukaryotic life preserved in Antarctic permafrost

    Onofri, Silvano; Zucconi, Laura; Selbmann, Laura; Ripa, Caterina; Frisvad, Jens Christian; Guglielmin, Mauro; Turchetti, Benedetta; Buzzini, Pietro

    Permafrost is defined as a soil remaining at 0 C or below throughout two or more consecutive years. Mainly present in polar areas, it occurs in all ice-free areas of Continental Antarc-tica. With the evidences of the possible presence of water ice below the surface of Mars and Moon, permafrost is now considered a possible reservoir of prokaryotic and eukaryotic spores outside the Earth. Cultivable fungi and yeasts have been isolated from Antarctic permafrost collected at different depths (233, 316 and 335 cm) in the McMurdo Dry Valleys, the largest ice-free area in Antarctica, and identified with cultural, physiological and molecular methods. Filamentous fungi belonged to the genera Penicillium, Eurotium, Cladosporium, Alternaria, Engyodonthium, Cordiceps, Rhizopus, Aureobasidium, whereas yeasts belonged to the genera Cryptococcus and Sporidiobolus. Penicillia were the most represented, and the most frequently recorded species were Penicillium palitans and P. chrysogenum. Most of the species found have been already recorded in Antarctic ecosystems as well as in other cold habitats (Onofri et al., 2007); for Eurotium amstelodami and Cryptococcus stepposus these are the first isolations in Antarctica. All the filamentous fungal isolates can be defined as mesophilic having optimal growth temperatures at 20-25 C and poor growth at 0 C after prolonged incubation. All the yeast isolates grew within a wide range of temperature (from 4 to 25 C). The molecular anal-yses based on the ITS rDNA sequences, for filamentous fungi, and on D1/D2 domain of LSU rRNA gene and ITS sequences for yeasts, revealed that these genotypes do not deviate from the global gene pool of microorganisms commonly spreading worldwide at present. Annual mean permafrost temperature (MAPT) in the sampling area was -18.8 C in 2008, with daily fluctuations lower than 1 C/day at 1 m of depth, but less 0.5 C/year at the depth of 17 m (Guglielmin pers. com.), and maximum thaw depth not exceeding 1 m

  17. A review of Tertiary climate changes in southern South America and the Antarctic Peninsula. Part 1: Oceanic conditions

    Le Roux, J. P.

    2012-03-01

    -level falls. This would have resulted in a narrowing of the Drake Passage, an intensification of the Antarctic Circumpolar Current that enhanced the isolation of Antarctica from warmer northern waters, and increased glaciation on the Antarctic Peninsula. Colder ocean surface waters would also have trapped more CO2, enhancing climate cooling on the adjacent continents. During these periods the atmospheric belts shifted equatorward and increased the latitudinal thermal gradient, leading to higher wind velocities and enhanced oceanic upwelling along the western seaboard of Southern South America.

  18. Impact of biogenic very short-lived bromine on the Antarctic ozone hole during the 21st century

    Fernandez, Rafael P.; Kinnison, Douglas E.; Lamarque, Jean-Francois; Tilmes, Simone; Saiz-Lopez, Alfonso

    2017-02-01

    Active bromine released from the photochemical decomposition of biogenic very short-lived bromocarbons (VSLBr) enhances stratospheric ozone depletion. Based on a dual set of 1960-2100 coupled chemistry-climate simulations (i.e. with and without VSLBr), we show that the maximum Antarctic ozone hole depletion increases by up to 14 % when natural VSLBr are considered, which is in better agreement with ozone observations. The impact of the additional 5 pptv VSLBr on Antarctic ozone is most evident in the periphery of the ozone hole, producing an expansion of the ozone hole area of ˜ 5 million km2, which is equivalent in magnitude to the recently estimated Antarctic ozone healing due to the implementation of the Montreal Protocol. We find that the inclusion of VSLBr in CAM-Chem (Community Atmosphere Model with Chemistry, version 4.0) does not introduce a significant delay of the modelled ozone return date to 1980 October levels, but instead affects the depth and duration of the simulated ozone hole. Our analysis further shows that total bromine-catalysed ozone destruction in the lower stratosphere surpasses that of chlorine by the year 2070 and indicates that natural VSLBr chemistry would dominate Antarctic ozone seasonality before the end of the 21st century. This work suggests a large influence of biogenic bromine on the future Antarctic ozone layer.

  19. Encouraging Advances Made by Chinese Scientists in Antarctic Research

    Zhang Qingsong

    2003-01-01

    @@ Chinese scientists began involving in the Antarctic research in 1980. As the first step, some 40 Chinese scientists were sent to Antarctic stations of Australia and other countries during the period from 1980 to 1984. Then,China established two Antarctic stations of its own, and purchased an icebreaker, enabling China to carry on its own independent research program both on land and at sea.

  20. Antarctic microfungi as models for exobiology

    Onofri, S.; Selbmann, L.; Zucconi, L.; Pagano, S.

    2004-01-01

    Microfungi living in different Antarctic environments are generally well adapted to high stress conditions such as low temperatures, wide thermal fluctuations, high UV irradiance, and low water and nutrients availability; for this reason they could be investigated in order to explore limits of microbial life. Microfungi living in simple cryptoendolithic microbial communities inside the porosity of rocks in the Antarctic Dry Valleys, the closest terrestrial analogue of Mars, are particularly suitable for exobiological studies. Until now studies on exobiology focused mainly on prokaryotes; since cryptoendolithic black meristematic fungi are able to tolerate hard desiccation, high UV exposure, extremely low temperatures and wide thermal fluctuations, they are proposed as the best eukaryotic models for the biological exploration of Mars. Indeed, their adaptive strategies could be crucial as predictive tools in investigating the limits of life.

  1. A simulated Antarctic fast ice ecosystem

    Arrigo, Kevin R.; Kremer, James N.; Sullivan, Cornelius W.

    1993-01-01

    A 2D numerical ecosystem model of Antarctic land fast ice is developed to elucidate the primary production with the Antarctic sea ice zone. The physical component employs atmospheric data to simulate congelation ice growth, initial brine entrapment, desalination, and nutrient flux. The biological component is based on the concept of a maximum temperature-dependent algal growth rate which is reduced by limitations imposed from insufficient light or nutrients, as well as suboptimal salinity. Preliminary simulations indicate that, during a bloom, microalgae are able to maintain their vertical position relative to the lower congelation ice margin and are not incorporated into the crystal matrix as the ice sheet thickens. It is inferred that land fast sea ice contains numerous microhabitats that are functionally distinct based upon the unique set of processes that control microalgal growth and accumulation within each.

  2. Total Mercury in Six Antarctic Notothenioid Fishes.

    Wintle, Nathan J P; Sleadd, Isaac M; Gundersen, Deke T; Kohl, Kristina; Buckley, Bradley A

    2015-11-01

    We analyzed white muscle samples from six species of Antarctic fish (suborder Notothenioidei) collected in 2011 from McMurdo Sound, Ross Sea, Antarctica, to assess levels of total mercury (THg). Gymnodraco acuticeps and Trematomus bernacchii exhibited the highest concentrations of THg followed by Trematomus pennellii, Trematomus nicolai, Trematomus newnesi and Pagothenia borchgrevinki, (71.3, 53.9±32.1, 45.8±27.3, 37.2±18.6, 35.7±23.6, and 21.9±2.8 ng/g wet weight, respectively). The results from this study suggest that THg has the potential to bioaccumulate from various marine Antarctic ecosystems into biota.

  3. Antarctic Meteorite Classification and Petrographic Database

    Todd, Nancy S.; Satterwhite, C. E.; Righter, Kevin

    2011-01-01

    The Antarctic Meteorite collection, which is comprised of over 18,700 meteorites, is one of the largest collections of meteorites in the world. These meteorites have been collected since the late 1970's as part of a three-agency agreement between NASA, the National Science Foundation, and the Smithsonian Institution [1]. Samples collected each season are analyzed at NASA s Meteorite Lab and the Smithsonian Institution and results are published twice a year in the Antarctic Meteorite Newsletter, which has been in publication since 1978. Each newsletter lists the samples collected and processed and provides more in-depth details on selected samples of importance to the scientific community. Data about these meteorites is also published on the NASA Curation website [2] and made available through the Meteorite Classification Database allowing scientists to search by a variety of parameters

  4. Optical Turbulence above the Internal Antarctic Plateau

    Masciadri, E; Hagelin, S; Moigne, P Le; Noilhan, J

    2010-01-01

    The internal antarctic plateau revealed in the last years to be a site with interesting potentialities for the astronomical applications due to the extreme dryness and low temperatures, the typical high altitude of the plateau, the weak level of turbulence in the free atmosphere down to a just few tens of meters from the ground and the thin optical turbulence layer developed at the ground. The main goal of a site testing assessment above the internal antarctic plateau is to characterize the site (optical turbulence and classical meteorological parameters) and to quantify which is the gain we might obtain with respect to equivalent astronomical observations done above mid-latitude sites to support plans for future astronomical facilities. Our group is involved, since a few years, in studies related to the assessment of this site for astronomical applications that include the characterization of the meteorological parameters and optical turbulence provided by general circulation models as well as mesoscale atmo...

  5. Assessing environmental conditions of Antarctic footpaths to support management decisions.

    Tejedo, Pablo; Benayas, Javier; Cajiao, Daniela; Albertos, Belén; Lara, Francisco; Pertierra, Luis R; Andrés-Abellán, Manuela; Wic, Consuelo; Luciáñez, Maria José; Enríquez, Natalia; Justel, Ana; Reck, Günther K

    2016-07-15

    Thousands of tourists visit certain Antarctic sites each year, generating a wide variety of environmental impacts. Scientific knowledge of human activities and their impacts can help in the effective design of management measures and impact mitigation. We present a case study from Barrientos Island in which a management measure was originally put in place with the goal of minimizing environmental impacts but resulted in new undesired impacts. Two alternative footpaths used by tourist groups were compared. Both affected extensive moss carpets that cover the middle part of the island and that are very vulnerable to trampling. The first path has been used by tourists and scientists since over a decade and is a marked route that is clearly visible. The second one was created more recently. Several physical and biological indicators were measured in order to assess the environmental conditions for both paths. Some physical variables related to human impact were lower for the first path (e.g. soil penetration resistance and secondary treads), while other biochemical and microbiological variables were higher for the second path (e.g. β-glucosidase and phosphatase activities, soil respiration). Moss communities located along the new path were also more diverse and sensitive to trampling. Soil biota (Collembola) was also more abundant and richer. These data indicate that the decision to adopt the second path did not lead to the reduction of environmental impacts as this path runs over a more vulnerable area with more outstanding biological features (e.g. microbiota activity, flora and soil fauna diversity). In addition, the adoption of a new route effectively doubles the human footprint on the island. We propose using only the original path that is less vulnerable to the impacts of trampling. Finally from this process, we identify several key issues that may be taken into account when carrying out impact assessment and environmental management decision-making in the

  6. Gas chromatography-mass spectrometry analysis of fatty acid profiles of Antarctic and non-Antarctic yeasts.

    Bhuiyan, Mohammad; Tucker, David; Watson, Kenneth

    2014-08-01

    The fatty acid profiles of Antarctic (n = 7) and non-Antarctic yeasts (n = 7) grown at different temperatures were analysed by gas chromatography-mass spectrometry. The Antarctic yeasts were enriched in oleic 18:1 (20-60 %), linoleic 18:2 (20-50 %) and linolenic 18:3 (5-40 %) acids with lesser amounts of palmitic 16:0 (Antarctic yeasts (n = 4) were enriched in 18:1 (20-55 %, with R. mucilaginosa at 75-80 %) and 18:2 (10-40 %) with lesser amounts of 16:0 (Antarctic yeasts (enriched in 18:1 and 18:2) and the third to the Antarctic yeasts (enriched in 18:2 and 18:3).

  7. Italian research on Antarctic atmosphere: 1st workshop. Ricerche italiane sull'atmosfera antartica: 1o workshop

    Colacino, M. (ed.); Giovannelli, G. (ed.); Stefanutti, L. (ed.)

    1989-01-01

    The papers and reports, presented at this 1st workshop on 'Italian research on antarctic atmosphere', deal with several main topics: meteorology and climatology, aerosol and tropospheric clouds, planetary boundary layer, chemical-physic stratospheric property, aeronomy. They define the stage of development of Italian research in this area after 3 years of activity in Antarctica.

  8. Magnetic anisotropy and porosity of Antarctic chondrites

    Hamano,Yozo/Yomogida,Kiyoshi

    1982-01-01

    Magnetic susceptibility anisotropy and porosity were measured in eleven Antarctic meteorites. These meteorites are ordinary chondrites (H and L type) in various metamorphic stages. Large magnetic anisotropy has been observed in most of the chondrites. The foliation type of the anisotropy, inferred from the shape of the susceptibility ellipsoid indicates that a uniaxial compressional type deformation is responsible for the anisotropy. The degree of the anisotropy and the porosity do not correl...

  9. A paleomagnetic study of the Antarctic Peninsula

    Poblete, F.; Arriagada, C.; Roperch, P.

    2009-05-01

    In the Paleozoic, South America, South Africa and Antarctica were part of Gondwana. The Weddell Sea began to form at about 146 Ma, after rifting between the Antarctic Peninsula and southernmost South America. Much uncertainty still exists about the geometrical fit and subsequent drift history between Patagonia and Antarctica. Geophysical and geological data which describe the tectonic history are sparsely distributed and often of poor quality. During the last two years we have collected more than 1000 paleomagnetic samples from 70 sites at several localities (King George Island, Robert Island, Yankee Bay, Half Moon Island, Byers Peninsula and Snow Island) from the South Shetland Islands and Anderson Island in the northern tip of Antarctic Peninsula. Our main objective was to provide first-order constraints on latitudinal displacements and the amount of tectonic rotations as an essential test of published tectonic models. Paleomagnetic results were obtained from 50 sites. All samples from sites in volcanic and intrusive rocks have well-defined univectorial magnetizations. Unfortunately, all sites in late Paleozoic sediments have been remagnetized and the magnetizations are often unstable upon thermal demagnetization. Cretaceous and Cenozoic units display very little apparent polar wander. Results from intrusive rocks of expected Jurassic age do not confirm the expected relative rotation betwen the Antarctic Peninsula and East Antarctica. Further radiometric dating are needed to confirm the age of these units.

  10. Antarctic Treaty Summit: Washington, DC (2009)

    Berkman, P. A.; Young, O. R.

    2005-12-01

    Advancement in Earth system science and international cooperation have been intertwined with the International Polar Years since 1882. In particular, the 3rd International Polar Year (which was convened as the International Geophysical Year from 1 July 1957 through 31 December 1958) specifically demonstrates the role of science in international policy: Acknowledging the substantial contributions to scientific knowledge resulting from international cooperation in scientific investigation in Antarctica; Convinced that the establishment of a firm foundation for the continuation and development of such cooperation on the basis of freedom of scientific investigation in Antarctica as applied during the International Geophysical Year accords with the interests of science and the progress of all mankind; Preamble, 1959 Antarctic Treaty To commemorate the 50th anniversary of the 1959 Antarctic Treaty and to explore the complexities of the science-policy relationship through the lens of a well-constrained case study, an international and interdisciplinary Antarctic Treaty Summit is being planned for 2009 in Washington, DC in conjunction with the International Polar Year 2007-08 (http://www.ipy.org).

  11. Antarctic Meteorite Classification and Petrographic Database Enhancements

    Todd, N. S.; Satterwhite, C. E.; Righter, K.

    2012-01-01

    The Antarctic Meteorite collection, which is comprised of over 18,700 meteorites, is one of the largest collections of meteorites in the world. These meteorites have been collected since the late 1970 s as part of a three-agency agreement between NASA, the National Science Foundation, and the Smithsonian Institution [1]. Samples collected each season are analyzed at NASA s Meteorite Lab and the Smithsonian Institution and results are published twice a year in the Antarctic Meteorite Newsletter, which has been in publication since 1978. Each newsletter lists the samples collected and processed and provides more in-depth details on selected samples of importance to the scientific community. Data about these meteorites is also published on the NASA Curation website [2] and made available through the Meteorite Classification Database allowing scientists to search by a variety of parameters. This paper describes enhancements that have been made to the database and to the data and photo acquisition process to provide the meteorite community with faster access to meteorite data concurrent with the publication of the Antarctic Meteorite Newsletter twice a year.

  12. Antarctic isolation: immune and viral studies

    Tingate, T. R.; Lugg, D. J.; Muller, H. K.; Stowe, R. P.; Pierson, D. L.

    1997-01-01

    Stressful environmental conditions are a major determinant of immune reactivity. This effect is pronounced in Australian National Antarctic Research Expedition populations exposed to prolonged periods of isolation in the Antarctic. Alterations of T cell function, including depression of cutaneous delayed-type hypersensitivity responses and a peak 48.9% reduction of T cell proliferation to the mitogen phytohaemagglutinin, were documented during a 9-month period of isolation. T cell dysfunction was mediated by changes within the peripheral blood mononuclear cell compartment, including a paradoxical atypical monocytosis associated with altered production of inflammatory cytokines. There was a striking reduction in the production by peripheral blood mononuclear cells of the predominant pro-inflammatory monokine TNF-alpha and changes were also detected in the production of IL-1, IL-2, IL-6, IL-1ra and IL-10. Prolonged Antarctic isolation is also associated with altered latent herpesvirus homeostasis, including increased herpesvirus shedding and expansion of the polyclonal latent Epstein-Barr virus-infected B cell population. These findings have important long-term health implications.

  13. Mirror seeing of the Antarctic survey telescope

    ZHANG Kaiyuan; LI Zhengyang; YUAN Xiangyan; PEI Chong

    2014-01-01

    Site testing results indicate that Antarctic Dome A is an excellent ground-based astronomical site suitable for observations ranging from visible to infrared wavelengths. However, the harsh environment in Antarctica, especially the very low temperature and atmospheric pressure, always produces frost on the telescopes’ mirrors, which are exposed to the air. Since the Dome A site is still unattended, the Antarctic telescope tubes are always designed to be filled with dry nitrogen, and the outer surfaces of the optical system are heated by an indium-tin oxide thin film. These precautions can prevent the optical surfaces from frosting over, but they degrade the image quality by introducing additional mirror seeing. Based on testing observations of the second Antarctic Survey Telescope (AST3-2) in the Mohe site in China, mirror seeing resulting from the heated aspheric plate has been measured using micro-thermal sensors. Results comparing the real-time atmospheric seeing monitored by the Differential Image Motion Monitor and real-time examinations of image quality agree well.

  14. Update on terrestrial ages of Antarctic meteorites

    Welten, K C; Nishiizumi, K; Caffee, M W

    2000-01-14

    Terrestrial ages of Antarctic meteorites are one of the few parameters that will help us to understand the meteorite concentration mechanism on blue-ice fields. Traditionally, terrestrial ages were determined on the basis of {sup 36}Cl in the metal phase, which has an uncertainty of about 70 ky. For young meteorites (< 40 ky), the terrestrial age is usually and most accurately determined using {sup 14}C in the stone phase. In recent years two methods have been developed which are independent of shielding effects, the {sup 10}Be-{sup 36}Cl/{sup 10}Be method and the {sup 41}Ca/{sup 36}Cl method. These methods have reduced the typical uncertainties in terrestrial ages by a factor of 2, to about 30 ky. The {sup 10}Be-{sup 36}Cl/{sup 10}Be method is quite dependent on the exposure age, which is unknown for most Antarctic meteorites. The authors therefore also attempt to use the relation between {sup 26}Al and {sup 36}Cl/{sup 26}Al to derive a terrestrial age less dependent on the exposure age. The authors have measured the concentrations of cosmogenic {sup 10}Be, {sup 26}Al and {sup 36}Cl in the metal phase of {approximately} 70 Antarctic meteorites, from more than 10 different ice-fields, including many new ones. They then discuss the trends in terrestrial ages of meteorites from different ice-fields.

  15. Adjacent-level arthroplasty following cervical fusion.

    Rajakumar, Deshpande V; Hari, Akshay; Krishna, Murali; Konar, Subhas; Sharma, Ankit

    2017-02-01

    OBJECTIVE Adjacent-level disc degeneration following cervical fusion has been well reported. This condition poses a major treatment dilemma when it becomes symptomatic. The potential application of cervical arthroplasty to preserve motion in the affected segment is not well documented, with few studies in the literature. The authors present their initial experience of analyzing clinical and radiological results in such patients who were treated with arthroplasty for new or persistent arm and/or neck symptoms related to neural compression due to adjacent-segment disease after anterior cervical discectomy and fusion (ACDF). METHODS During a 5-year period, 11 patients who had undergone ACDF anterior cervical discectomy and fusion (ACDF) and subsequently developed recurrent neck or arm pain related to adjacent-level cervical disc disease were treated with cervical arthroplasty at the authors' institution. A total of 15 devices were implanted (range of treated levels per patient: 1-3). Clinical evaluation was performed both before and after surgery, using a visual analog scale (VAS) for pain and the Neck Disability Index (NDI). Radiological outcomes were analyzed using pre- and postoperative flexion/extension lateral radiographs measuring Cobb angle (overall C2-7 sagittal alignment), functional spinal unit (FSU) angle, and range of motion (ROM). RESULTS There were no major perioperative complications or device-related failures. Statistically significant results, obtained in all cases, were reflected by an improvement in VAS scores for neck/arm pain and NDI scores for neck pain. Radiologically, statistically significant increases in the overall lordosis (as measured by Cobb angle) and ROM at the treated disc level were observed. Three patients were lost to follow-up within the first year after arthroplasty. In the remaining 8 cases, the duration of follow-up ranged from 1 to 3 years. None of these 8 patients required surgery for the same vertebral level during the follow

  16. Potential climate change effects on the habitat of antarctic krill in the weddell quadrant of the southern ocean.

    Simeon L Hill

    Full Text Available Antarctic krill is a cold water species, an increasingly important fishery resource and a major prey item for many fish, birds and mammals in the Southern Ocean. The fishery and the summer foraging sites of many of these predators are concentrated between 0° and 90°W. Parts of this quadrant have experienced recent localised sea surface warming of up to 0.2°C per decade, and projections suggest that further widespread warming of 0.27° to 1.08°C will occur by the late 21(st century. We assessed the potential influence of this projected warming on Antarctic krill habitat with a statistical model that links growth to temperature and chlorophyll concentration. The results divide the quadrant into two zones: a band around the Antarctic Circumpolar Current in which habitat quality is particularly vulnerable to warming, and a southern area which is relatively insensitive. Our analysis suggests that the direct effects of warming could reduce the area of growth habitat by up to 20%. The reduction in growth habitat within the range of predators, such as Antarctic fur seals, that forage from breeding sites on South Georgia could be up to 55%, and the habitat's ability to support Antarctic krill biomass production within this range could be reduced by up to 68%. Sensitivity analysis suggests that the effects of a 50% change in summer chlorophyll concentration could be more significant than the direct effects of warming. A reduction in primary production could lead to further habitat degradation but, even if chlorophyll increased by 50%, projected warming would still cause some degradation of the habitat accessible to predators. While there is considerable uncertainty in these projections, they suggest that future climate change could have a significant negative effect on Antarctic krill growth habitat and, consequently, on Southern Ocean biodiversity and ecosystem services.

  17. The ARM West Antarctic Radiation Experiment (AWARE)

    Lubin, Dan; Bromwich, David; Vogelmann, Andrew; Verlinde, Johannes; Russell, Lynn

    2016-04-01

    West Antarctica is one of the most rapidly warming regions on Earth, and its changing climate in both atmosphere and ocean is linked to loss of Antarctic ice mass and global sea level rise. The specific mechanisms for West Antarctic Ice Sheet (WAIS) warming are not fully understood, but are hypothesized to involve linkage between moisture from Southern Ocean storm tracks and the surface energy balance over the WAIS, and related teleconnections with subtropical and tropical meteorology. This present lack of understanding has motivated a climate science and cloud physics campaign jointly supported by the US National Science Foundation (NSF) and Department of Energy (DOE), called the Atmospheric Radiation Measurement Program (ARM) West Antarctic Radiation Experiment (AWARE). The DOE's second ARM Mobile Facility (AMF2) was deployed to McMurdo Station on Ross Island in November 2015 and will operate through December 2016. The AMF2 includes (1) cloud research radars, both scanning and zenith, operating in the Ka- and X-bands, (2) high spectral resolution and polarized micropulse lidars, and (3) a suite of shortwave and longwave broadband and spectral radiometers. A second suite of instruments is deployed at the WAIS Divide Ice Camp on the West Antarctic plateau during December 2015 and January 2016. The WAIS instrument suite provides (1) measurement of all surface energy balance components, (2) a polarized micropulse lidar and shortwave spectroradiometer, (3) microwave total water column measurement, and (4) four times daily rawinsonde launches which are the first from West Antarctica since 1967. There is a direct linkage between the WAIS instrument suite and the AMF2 at McMurdo, in that air masses originating in Southern Ocean storm tracks that are driven up over the WAIS often subsequently descend over the Ross Ice Shelf and arrive at Ross Island. Preliminary data are already illustrating the prevalence of mixed-phase clouds and their role in the surface energy balance

  18. Kauffman's adjacent possible in word order evolution

    Ferrer-i-Cancho, Ramon

    2015-01-01

    Word order evolution has been hypothesized to be constrained by a word order permutation ring: transitions involving orders that are closer in the permutation ring are more likely. The hypothesis can be seen as a particular case of Kauffman's adjacent possible in word order evolution. Here we consider the problem of the association of the six possible orders of S, V and O to yield a couple of primary alternating orders as a window to word order evolution. We evaluate the suitability of various competing hypotheses to predict one member of the couple from the other with the help of information theoretic model selection. Our ensemble of models includes a six-way model that is based on the word order permutation ring (Kauffman's adjacent possible) and another model based on the dual two-way of standard typology, that reduces word order to basic orders preferences (e.g., a preference for SV over VS and another for SO over OS). Our analysis indicates that the permutation ring yields the best model when favoring pa...

  19. Polycyclic aromatic hydrocarbons (PAHS) contamination in aquatic environments adjacent to areas of multiple uses: to whom is that environmental liability?; Contaminacao por hidrocarbonetos aromaticos policiclicos (HPAS) em ambientes aquaticos adjacentes a areas de multiplos usos: a quem corresponde esse passivo ambiental?

    Garcia, Marina R.D.; Mirlean, Nicolai; Machado, Maria Isabel C.S. [Fundacao Universidade Federal do Rio Grande (FURG), RS (Brazil); Caramao, Elina B. [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

    2004-07-01

    Contamination often can be related to different activities, especially in areas with multiple uses. In these cases, studies are necessary to correctly evaluate the origin of contaminants. Polycyclic aromatic hydrocarbons (PAHs) are organic compounds that have two main sources: pyrolytic and petrogenic processes. In Rio Grande City, located at the margins of Patos Lagoon estuary, south Brazil, there are several navigation and industrial activities. This work has the objective to determinate the origins of PAHs and to evaluate the contribution of different sources to the aquatic contamination. The sampling stations were classified according to three main types: industrial effluent, sewage and runoff. We collected sediments from the bottom of effluent channels and from the respective estuarine environments. The material was sieved (0,063 mm), dried, extracted in soxhlet apparatus with methylene chloride and GC-MS analyzed. The results showed that pyrolytic compounds were predominant, indicating the contribution of diffuse sources. This type of study was successful in relating PAHs with their sources, confirming the role of urban and other industries activities in this case of contamination, superimposed to the midstream e downstream activities of petroleum industry. (author)

  20. Geoethical Approach to Antarctic Subglacial Lakes Exploration

    Talalay, Pavel; Markov, Alexey; Sysoev, Mikhail

    2014-05-01

    Antarctic subglacial aquatic environment have become of great interest to the science community because they may provide unique information about microbial evolution, the past climate of the Earth, and the formation of the Antarctic ice sheet. Nowadays it is generally recognized that a vast network of lakes, rivers, and streams exists thousands of meters beneath Antarctic Ice Sheets. Up to date only four boreholes accessed subglacial aquatic system but three of them were filled with high-toxic drilling fluid, and the subglacial water was contaminated. Two recent exploration programs proposed by UK and USA science communities anticipated direct access down to the lakes Ellsworth and Whillans, respectively, in the 2012/2013 Antarctic season. A team of British scientists and engineers engaged in the first attempt to drill into Lake Ellsworth but failed. US research team has successfully drilled through 800 m of Antarctic ice to reach a subglacial lake Whillans and retrieve water and sediment samples. Both activities used hot-water drilling technology to access lakes. Hot water is considered by the world science community as the most clean drilling fluid medium from the present point of view but it cannot solve environmental problems in total because hot-water even when heated to 90 °C, filtered to 0.2 μm, and UV treated at the surface could pick up microorganisms from near-surface snow and circulate them in great volume through the borehole. Another negative impact of hot-water circulation medium is thermal pollution of subglacial water. The new approach to Antarctic subglacial lakes exploration is presented by sampling technology with recoverable autonomous sonde which is equipped by two hot-points with heating elements located on the bottom and top sides of the sonde. All down-hole sonde components will be sterilized by combination of chemical wash, HPV and UV sterilization prior using. At the beginning of the summer season sonde is installed on the surface of the

  1. Distributions of surface sediments surrounding the Antarctic Peninsula and its environmental significance

    WANG Chunjuan; CHEN Zhihua; LI Chunshun; DU Dewen; YAN Shijuan; ZHU Zhiwei

    2014-01-01

    We analyzed grain size composition to provide information on the types and distributions as well as depositional varieties of marine surface sediments from the area surrounding the Antarctic Peninsula. The samples retrieved from the study area contain gravel, sand, silt and clay. As suggested by bathymetry and morphology, the study area is characterized by neritic, hemipelagic and pelagic deposits. The glacial-marine sediments can be divided into two types, residual paratill and compound paratill, which are primarily transported by glaciers and as ice-rafted debris. Ocean current effects on deposition are more obvious, and the deposit types are distributed consistently with terrain variations.

  2. Seismic anisotropy of upper mantle in Sichuan and adjacent regions

    CHANG LiJun; WANG ChunYong; DING ZhiFeng

    2008-01-01

    Based on the polarization analysis of teleseismic SKS waveform data recorded at 94 broadband seismic stations in Sichuan and adjacent regions, the SKS fast-wave direction and the delay time between the fast and slow shear waves were determined at each station using the grid searching method of minimum transverse energy and the stacking analysis method, and the image of upper mantle anisotropy was acquired. The fast-wave polarization directions are mainly NW-SE in the study area,NWW-SEE to its northeast and NS to its west. The delay time falls into the interval [0.47 s, 1.68 s]. The spatial variation of the fast-wave directions is similar to the variation of GPS velocity directions. The anisotropic image indicates that the regional tectonic stress field has resulted in deformation and flow of upper mantle material, and made the alignment of upper mantle peridotite lattice parallel to the direction of material deformation. The crust-upper mantle deformation in Sichuan and adjacent regions accords with the mode of vertically coherent deformation. In the eastern Tibetan Plateau, the crustal material was extruded to east or southeast clue to SE traction force of the upper mantle material. The extrusion might be obstructed by a rigid block under the Sichuan Basin and the crust has been deformed. After a long-term accumulation of tectonic strain energy, the accumulative energy suddenly released in Yingxiu town of the Longmenshan region, and Wenchuan Ms8.0 earthquake occurred.

  3. 连云港田湾核电站邻近海域网采浮游植物群落的变化%Changes of Net-collected Phytoplankton Community in Sea Area Adjacent to Tianwan Nuclear Power Plant of Lianyungang

    万晔; 杨华; 刘吉堂; 马润美; 程祥圣; 王超; 葛修军; 朱旭宇

    2014-01-01

    The net-collected phytoplankton in the sea area adjacent to Tianwan Nuclear Power Plant of Lianyungang was in -vestigated in May 2011, August 2012 and August 2013, and their species composition , annual changes and relations with environ-mental factors were studied .A total of 160 phytoplankton species in 8 phyla were identified , including 113 diatom species , 31 dino-flagellate species and other 18 taxonomic ( Chlorophyta , Chrysophyta , Euglenophyta , Cyanophyt , Xanthophyta and Cryptophyta ) species.Dominant species consisted of 7 diatom species and 1 dinoflagellate species.The correlation analysis showed that the cell density of phytoplankton was significantly positively correlated with phosphate concentration , nitrite concentration and temperature , and was negatively correlated with salinity .Since the year 1983, the structure of nutritive salt in the studied sea area has changed obviously:the concentration of phosphate sharply increased from 0.70μmol/L in 1983 to 29.38μmol/L in 2013;the ratio of N to P also increased from 4.9∶1 in 1983 to 53.7∶1 in 2013.Meanwhile, the structure of phytoplankton community has also experienced an obvious variation since 1983, and the dominant species Chaetoceros spp.was gradually replaced by Skeletonema spp.%根据2011年5月、2012年8月和2013年8月在连云港田湾核电站邻近海域进行的调查,研究了网采浮游植物的种类组成、年际变化及其与环境因子的关系。该海域共鉴定出浮游植物8门160种,其中硅藻种类数最多(113种),甲藻其次(31种),蓝藻、金藻、黄藻、绿藻、裸藻和隐藻偶有检出。优势种共8种,包括7种硅藻和1种甲藻。相关性分析表明,浮游植物细胞丰度与磷酸盐、亚硝酸盐和温度呈显著正相关,与盐度呈负相关。结合历史数据分析表明,近30年来核电站邻近海域营养盐结构已发生较大变化,表现为硝酸盐浓度急剧升高,由1983年的0.70

  4. Development of a multi-parameter system for Antarctic researching

    Garcia, Alicia; Peci, Luis Miguel; Berrocoso, Manuel; Fernandez-Ros, Alberto; Marrero, Jose Manuel; Ortiz, Ramon

    2014-05-01

    This work describes the development of a multi-parameter system for antarctic researching. The system permits the remote access and the connection of several modules in a network. An embedded ARM processor has been used, allowing a great flexibility in hardware configuration.The advantage of the system presented in this work is that it allows the rapid development of a monitoring network that uses the latest technologies of embedded systems. These embedded systems offer the possibility of developing the software necessary for managing the sensors and instruments available. Data can be transmitted in near real time or on demand to a Data Reception Center (DRC). The local storage allows retrieving data when the transmission fails and uses only short transmission periods rather than continuous transmission. The price of both hardware and software is very low. The use of a complete Linux solution (Debian) as Operating System permits a quick, easy application development to control sensors and communications. This provides all the capabilities required and great stability with relatively low energy consumption. The cost of the components and applications development is low since they are widely used in different fields. Sensors and commercial modules have been combined with other self-developed modules. The Modular System described has been deployed at Deception Island (Antarctica), within the Spanish Antarctic Program, and has proved successful for monitoring and researching the geodinamical activity, with proven reliability and efficient operation under extreme conditions. Deception Islan is an active volcano with some geothermal areas, this fact has allowed to develop a power system using Peltier cells. In another context, i.e., the recent volcanic activity on El Hierro Island (Canary Islands) in 2011, this technology has been used for the seismic equipment and GPS systems deployed, thus showing its efficiency in the monitoring of a volcanic crisis.

  5. Detecting Adjacent Relativity of Engineering Drawing Entities with Container Window

    林福严; 邱友申; 秦吉胜

    2001-01-01

    Automatic recognition and interpretation of engineering drawing plays an important role in computer aided engineering. Detecting the positional relation between entities is an important topic in this research field. In this paper the concepts of adjacent relativity and container window of drawing entities were proposed. By means of container window, the adjacent irrelative entities can be detected quickly and effectively, which speeds up the process of adjacent relativity detection. Meanwhile, the algorithm of adjacent relativity detection was discussed.

  6. Biodegradation of petroleum products in experimental plots in Antarctic marine sediments is location dependent.

    Powell, Shane M; Harvey, Paul McA; Stark, Jonathan S; Snape, Ian; Riddle, Martin J

    2007-04-01

    Clean sediment collected from O'Brien Bay, East Antarctica, was artificially contaminated with a mix of Special Antarctic Blend diesel fuel and lubricating oil and deployed in two uncontaminated locations (O'Brien and Sparkes Bays) and a previously contaminated bay (Brown Bay) to evaluate whether a history of prior contamination would influence the biodegradation process. Detailed analysis of the hydrocarbon composition in the sediment after 11 weeks revealed different patterns of degradation in each bay. Biodegradation indices showed that hydrocarbon biodegradation occurred in all three bays but was most extensive in Brown Bay. This study shows that even within a relatively small geographical area, the longevity of hydrocarbons in Antarctic marine sediments can be variable. Our results are consistent with faster natural attenuation of spilt oil at sites with previous exposure to oil but further work is needed to confirm this. Such information would be useful when evaluating the true risk and longevity of oils spills.

  7. Rock black fungi: excellence in the extremes, from the Antarctic to space.

    Selbmann, Laura; Zucconi, Laura; Isola, Daniela; Onofri, Silvano

    2015-08-01

    This work focuses on rock-inhabiting fungi (RIF) of Antarctic rocky deserts, considered the closest to a possible Martian habitat, as the best example of adaptation to the extremes. The study of RIF ecophysiology, resistance and adaptation provides tools that shed light on the evolution of extremophily. These studies also help define the actual limits for life and provide insight for investigating its existence beyond our planet. The scientific results obtained from over 20 years of research on the biodiversity, phylogeny and evolution toward extremotolerance reviewed here demonstrate how these fascinating organisms can withstand conditions well beyond those in their natural environment. A final focus is given on results and perspectives arising from a recent proteomic approach, and from astrobiological experiments and their significance for future space exploration. These studies demonstrate that Antarctic RIF offer an excellent opportunity to investigate many basic, but also applicative areas of research on extremophily.

  8. Development and Applications of Dome A-DEM in Antarctic Ice Sheet

    LIU Jiying; WEN Jiahong; WANG Yafeng; WANG Weili; Beata M CATHSO; Kenneth C JEZEK

    2007-01-01

    Dome A, the highest dome of East Antarctic Ice Sheet, is being an area focused by international Antarctic community after Chinese Antarctic Expedition finally reached there in 2005, and with the ongoing International Polar Year (IPY) during August 2007. In this paper two data processing methods are used together to generate two 100-m cell size digital elevation models (DEMs) of the Dome A region (Dome A-DEM) by using Cokriging method to interpolate the ICESat GLAS data, with Ihde-DEM as a constraint. It provides fundamental data to glaciological and geophysical investigation in this area. The Dome A-DEM was applied to determining the ice-sheet surface elevations and coordinates of the south and north summits, defining boundaries of basins and ice flowlines, deducing subglacial topography, and mapping surface slope and aspect in Dome A region. The DEM shows there are two (north and south) summits in Dome A region. The coordinate and the surface elevation of the highest point (the north summit) are 80°21'29.86"S, 77°21'50.29"E and 4092.71±1.43m, respectively. The ice thickness and sub-ice bedrock elevation at north summit are 2420m and 1672m, respectively. Dome A region contains four drainage basins that meet together near the south summit. Ice flowlines, slope and aspect in detail are also derived using the DEM.

  9. Antarctic bacteria inhibit growth of foodborne microorganisms at low temperatures.

    A.C. O'Brien; R. Sharp; N.J. Russell; S. Roller

    2004-01-01

    The aim of this study was to identify Antarctic microorganisms with the ability to produce cold-active antimicrobial compounds with potential for use in chilled food preservation. Colonies (4496) were isolated from 12 Antarctic soil samples and tested against Listeria innocua, Pseudomonas fragi and

  10. The distribution of Fe in the Antarctic Circumpolar Current

    Löscher, B.M.; Baar, H.J.W. de; Jong, J.T.M. de; Veth, C.; Dehairs, F.

    1997-01-01

    The large-scale distributions of dissolved and total Fe in surface and deep waters of the Antarctic Circumpolar Current exhibit strong relationships with hydrography and biological processes. The mean dissolved Fe concentrations are low in surface waters of the Antarctic Circumpolar Current (0.31–0.

  11. Biological studies in the Antarctic waters: A review

    Dhargalkar, V.K.

    stream_size 12 stream_content_type text/plain stream_name Proc_Workshop_Antarct_Stud_1990_407.pdf.txt stream_source_info Proc_Workshop_Antarct_Stud_1990_407.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset...

  12. Ice core reconstruction of Antarctic climate change and implications

    Mayewski,Paul Andrew

    2012-01-01

    Antarctica is the Earth’s largest environmental library for ice cores. Examples of the scientific fin-dings of the 21-nation consortium called the International Trans Antarctic Scientific Expedition (ITASE) under the auspices of the Scientific Committee for Antarctic Research (SCAR) are presented with special emphasis on the value of these records in reconstructing atmospheric circulation over Antarctica and the Southern Ocean.

  13. Challenges to the Future - Conservation of the Antarctic

    Chown, S.L.; Lee, J.E.; Hughes, K.A.; Barnes, J.; Bergstrom, D.M.; Convey, P.; Cowan, D.A.; Crosbie, K.; Dyer, G.; Frenot, Y.; Grant, S.M.; Herr, D.; Kennicutt, M.C.; Lamers, M.A.J.; Murray, A.; Possingham, H.P.; Reid, K.; Riddle, M.J.; Ryan, P.G.; Sanson, L.; Shaw, J.D.; Sparrow, M.D.; Summerhayes, C.; Terauds, A.; Wall, D.H.

    2012-01-01

    The Antarctic Treaty System, acknowledged as a successful model of cooperative regulation of one of the globe's largest commons (1), is under substantial pressure. Concerns have been raised about increased stress on Antarctic systems from global environmental change and growing interest in the regio

  14. 77 FR 31044 - Permits Issued Under the Antarctic Conservation Act

    2012-05-24

    ... No: 2012-12616] NATIONAL SCIENCE FOUNDATION Permits Issued Under the Antarctic Conservation Act AGENCY: National Science Foundation. ACTION: Notice of permits issued under the Antarctic Conservation of 1978, Public Law 95-541. SUMMARY: The National Science Foundation (NSF) is required to publish...

  15. Transcriptome of the Antarctic brooding gastropod mollusc Margarella antarctica.

    Clark, Melody S; Thorne, Michael A S

    2015-12-01

    454 RNA-Seq transcriptome data were generated from foot tissue of the Antarctic brooding gastropod mollusc Margarella antarctica. A total of 6195 contigs were assembled de novo, providing a useful resource for researchers with an interest in Antarctic marine species, phylogenetics and mollusc biology, especially shell production.

  16. Exchange coupling between laterally adjacent nanomagnets

    Dey, H.; Csaba, G.; Bernstein, G. H.; Porod, W.

    2016-09-01

    We experimentally demonstrate exchange-coupling between laterally adjacent nanomagnets. Our results show that two neighboring nanomagnets that are each antiferromagnetically exchange-coupled to a common ferromagnetic bottom layer can be brought into strong ferromagnetic interaction. Simulations show that interlayer exchange coupling effectively promotes ferromagnetic alignment between the two nanomagnets, as opposed to antiferromagnetic alignment due to dipole-coupling. In order to experimentally demonstrate the proposed scheme, we fabricated arrays of pairs of elongated, single-domain nanomagnets. Magnetic force microscopy measurements show that most of the pairs are ferromagnetically ordered. The results are in agreement with micromagnetic simulations. The presented scheme can achieve coupling strengths that are significantly stronger than dipole coupling, potentially enabling far-reaching applications in Nanomagnet Logic, spin-wave devices and three-dimensional storage and computing.

  17. Semi-empirical models for chlorine activation and ozone depletion in the Antarctic stratosphere: proof of concept

    P. E. Huck

    2012-10-01

    Full Text Available Two semi-empirical models were developed for the Antarctic stratosphere to relate the shift of species within total chlorine (Cly = HCl + ClONO2 + HOCl + 2 × Cl2 + 2 × Cl2O2 + ClO + Cl into the active forms (here: ClOx = 2 × Cl2O2 + ClO, and to relate the rate of ozone destruction to ClOx. These two models provide a fast and computationally inexpensive way to describe the inter- and intra-annual evolution of ClOx and ozone mass deficit (OMD in the Antarctic spring. The models are based on the underlying physics/chemistry of the system and capture the key chemical and physical processes in the Antarctic stratosphere that determine the interaction between climate change and Antarctic ozone depletion. They were developed considering bulk effects of chemical mechanisms for the duration of the Antarctic vortex period and quantities averaged over the vortex area. The model equations were regressed against observations of daytime ClO and OMD providing a set of empirical fit coefficients. Both semi-empirical models are able to explain much of the intra- and inter-annual variability observed in daily ClOx and OMD time series. This proof-of-concept paper outlines the semi-empirical approach to describing the evolution of Antarctic chlorine activation and ozone depletion.

  18. Screening of microorganisms from Antarctic surface water and cytotoxicity metabolites from Antarctic microorganisms.

    Zheng, Lanhong; Yang, Kangli; Liu, Jia; Sun, Mi; Zhu, Jiancheng; Lv, Mei; Kang, Daole; Wang, Wei; Xing, Mengxin; Li, Zhao

    2016-03-01

    The Antarctic is a potentially important library of microbial resources and new bioactive substances. In this study, microorganisms were isolated from surface water samples collected from different sites of the Antarctic. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay-based cytotoxicity-tracking method was used to identify Antarctic marine microorganism resources for antitumor lead compounds. The results showed that a total of 129 Antarctic microorganism strains were isolated. Twelve strains showed potent cytotoxic activities, among which a Gram-negative, rod-shaped bacterium, designated as N11-8 was further studied. Phylogenetic analysis based on 16S rRNA gene sequence showed that N11-8 belongs to the genus Bacillus. Fermented active products of N11-8 with molecular weights of 1-30 kDa had higher inhibitory effects on different cancaer cells, such as BEL-7402 human hepatocellular carcinoma cells, U251 human glioma cells, RKO human colon carcinoma cells, A549 human lung carcinoma cells, and MCF-7 human breast carcinoma cells. However, they displayed lower cytotoxicity against HFL1 human normal fibroblast lung cells. However, they displayed lower cytotoxicity against HFL1 human normal fibroblast lung cells. Microscopic observations showed that the fermented active products have inhibitory activity on BEL-7402 cells similar to that of mitomycin C. Further studies indicated that the fermented active products have high pH and high thermal stability. In conclusion, most strains isolated in this study may be developed as promising sources for the discovery of antitumor bioactive substances. The fermented active products of Antarctic marine Bacillus sp. N11- 8 are expected to be applied in the prevention and treatment of cancer.

  19. Terrestrial and exposure histories of Antarctic meteorites

    Nishiizumi, K.

    1986-01-01

    Records of cosmogenic effects were studied in a large suite of Antarctic meteorites. The cosmogenic nuclide measurements together with cosmic ray track measurements on Antartic meteorites provide information such as exposure age, terrestrial age, size and depth in meteoroid or parent body, influx rate in the past, and pairing. The terrestrail age is the time period between the fall of the meteorite on the Earth and the present. To define terrestrial age, two or more nuclides with different half-lives and possibly noble gases are required. The cosmogenic radionuclides used are C-14, Kr-81, Cl-36, Al-26, Be-10, Mn-53, and K-40.

  20. Ultraviolet radiation levels during the Antarctic spring

    Frederick, John E.; Snell, Hilary E.

    1988-01-01

    The decrease in atmospheric ozone over Antarctica during spring implies enhanced levels of ultraviolet (UV) radiation received at the earth's surface. Model calculations show that UV irradiances encountered during the occurrence of an Antarctic 'ozone hole' remain less than those typical of a summer solstice at low to middle latitudes. However, the low ozone amounts observed in October 1987 imply biologically effective irradiances for McMurdo Station, Antarctica, that are comparable to or greater than those for the same location at December solstice. Life indigenous to Antarctica thereby experiences a greatly extended period of summerlike UV radiation levels.

  1. The Antarctic Ozone Hole: An Update

    Douglass, Anne R.; Newman, Paul A.; Solomon, Susan

    2014-01-01

    The stratospheric ozone hole, an annual occurrence during austral spring, is caused by heterogeneous conversion of hydrogen chloride and chlorine nitrate to chlorine radicals. These reactions take place of polar stratospheric cloud particles in the cold, isolate Antarctic winter vortex. The chlorine radicals participate in chemical reactions that rapidly deplete ozone when sunlight returns at the end of polar night. International agreements eliminated production of the culprit anthropogenic chlorofluorocarbons in the late 1990s, but due to their long stratospheric lifetime (50-100 years), the ozone hole will continue its annual appearance for years to come.

  2. The 2002 Antarctic Ozone Hole

    Newman, P. A.; Nash, E. R.; Douglass, A. R.; Kawa, S. R.

    2003-01-01

    Since 1979, the ozone hole has grown from near zero size to over 24 Million km2. This area is most strongly controlled by levels of inorganic chlorine and bromine oncentrations. In addition, dynamical variations modulate the size of the ozone hole by either cooling or warming the polar vortex collar region. We will review the size observations, the size trends, and the interannual variability of the size. Using a simple trajectory model, we will demonstrate the sensitivity of the ozone hole to dynamical forcing, and we will use these observations to discuss the size of the ozone hole during the 2002 Austral spring. We will further show how the Cly decreases in the stratosphere will cause the ozone hole to decrease by 1-1.5% per year. We will also show results from a 3-D chemical transport model (CTM) that has been continuously run since 1999. These CTM results directly show how strong dynamics acts to reduce the size of the ozone hole.

  3. Feedbacks between ice and ocean dynamics at the West Antarctic Filchner-Ronne Ice Shelf in future global warming scenarios

    Goeller, Sebastian; Timmermann, Ralph

    2016-04-01

    The ice flow at the margins of the West Antarctic Ice Sheet is moderated by large ice shelves. Their buttressing effect substantially controls the mass balance of the WAIS and thus its contribution to sea level rise. The stability of these ice shelves results from the balance of mass gain by accumulation and ice flow from the adjacent ice sheet and mass loss by calving and basal melting due to the ocean heat flux. Recent results of ocean circulation models indicate that warm circumpolar water of the Southern Ocean may override the submarine slope front of the Antarctic Continent and boost basal ice shelf melting. In particular, ocean simulations for several of the IPCC's future climate scenarios demonstrate the redirection of a warm coastal current into the Filchner Trough and underneath the Filchner-Ronne Ice Shelf within the next decades. In this study, we couple the finite elements ocean circulation model FESOM and the three-dimensional thermomechanical ice flow model RIMBAY to investigate the complex interactions between ocean and ice dynamics at the Filchner-Ronne Ice Shelf. We focus on the impact of a changing ice shelf cavity on ocean dynamics as well as the feedback of the resulting sub-shelf melting rates on the ice shelf geometry and implications for the dynamics of the adjacent marine-based Westantarctic Ice Sheet. Our simulations reveal the high sensitivity of grounding line migration to ice-ocean interactions within the Filchner-Ronne Ice Shelf and emphasize the importance of coupled model studies for realistic assessments of the Antarctic mass balance in future global warming scenarios.

  4. Identification of protein-RNA interaction sites using the information of spatial adjacent residues

    Cheng Yong-Mei

    2011-10-01

    Full Text Available Abstract Background Protein-RNA interactions play an important role in numbers of fundamental cellular processes such as RNA splicing, transport and translation, protein synthesis and certain RNA-mediated enzymatic processes. The more knowledge of Protein-RNA recognition can not only help to understand the regulatory mechanism, the site-directed mutagenesis and regulation of RNA–protein complexes in biological systems, but also have a vitally effecting for rational drug design. Results Based on the information of spatial adjacent residues, novel feature extraction methods were proposed to predict protein-RNA interaction sites with SVM-KNN classifier. The total accuracies of spatial adjacent residue profile feature and spatial adjacent residues weighted accessibility solvent area feature are 78%, 67.07% respectively in 5-fold cross-validation test, which are 1.4%, 3.79% higher than that of sequence neighbour residue profile feature and sequence neighbour residue accessibility solvent area feature. Conclusions The results indicate that the performance of feature extraction method using the spatial adjacent information is superior to the sequence neighbour information approach. The performance of SVM-KNN classifier is little better than that of SVM. The feature extraction method of spatial adjacent information with SVM-KNN is very effective for identifying protein-RNA interaction sites and may at least play a complimentary role to the existing methods.

  5. Gas explosion in a room with a window and passage to an adjacent room

    Polandov Yuri

    2016-01-01

    Full Text Available Some publications describe an effect, produced during a physical model experiment, when an adjacent gas-free room influences the gas explosion pressure in a room with a window. The explosion pressure in this case significantly exceeds (2.5 times the explosion pressure in a room without an adjacent room. This result has been confirmed by our studies. Based on other available information about the influence of the ignition point location on the explosion pressure in one room, it was suggested that this could be true for an explosion in two rooms. In our studies we used a test unit with two connected chambers, each having a volume of 1.125 m3. It turned out that this influence of the adjacent volume was not so unambiguous as it was described in those publications. It was found out that the maximum effect of explosion pressure amplification by the adjacent room is achieved, when the igniter is located in the chamber filled with a gas-air mixture in the area between the center of the chamber and the window (maximum amplification by more than 3 times. This effect is lower directly by the window (1.8 times and is practically absent in case of ignition within the area near the passage connecting the chamber with the adjacent room. This suggests that the effect discovered earlier is a special case of the general dependence of the gas explosion pressure in two chambers on the igniter location.

  6. Interaction between Adjacent Lightning Discharges in Clouds

    WANG Yanhui; ZHANG Guangshu; ZHANG Tong; LI Yajun; WU Bin; ZHANG Tinglong

    2013-01-01

    Using a 3D lightning radiation source locating system (LLS),three pairs of associated lightning discharges (two or more adjacent lightning discharges following an arbitrary rule that their space-gap was less than 10 km and their time-gap was less than 800 ms) were observed,and the interaction between associated lightning discharges was analyzed.All these three pairs of associated lightning discharges were found to involve three or more charge regions (the ground was considered as a special charge region).Moreover,at least one charge region involved two lightning discharges per pair of associated lightning discharges.Identified from electric field changes,the subsequent lightning discharges were suppressed by the prior lightning discharges.However,it is possible that the prior lightning discharge provided a remaining discharge channel to facilitate the subsequent lightning discharge.The third case provided evidence of this possibility.Together,the results suggested that,if the charges in the main negative charge region can be consumed using artificial lightning above the main negative charge regions,lightning accidents on the ground could be greatly reduced,on the condition that the height of the main negative charge region and the charge intensity of the lower positive charge region are suitable.

  7. When will the Antarctic Ozone Hole Recover?

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve

    2006-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the .TOMS instrument. The severity of the hole has been assessed from TOMS using the minimum total ozone value from the October monthly mean (depth of the hole) and by calculating the average size during the September-October period. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to, both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. Using projections of halogen levels combined with age-of-air estimates, we find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. The ozone hole will begin to show first signs of recovery in about 2023, and the hole will fully recover to pre-1980 levels in approximately 2070. This 2070 recovery is 20 years later than recent projections.

  8. Recovery of the Antarctic Ozone Hole

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve; Schauffler, Sue; Stolarski, Richard S.; Douglass, Anne R.; Pawson, Steven; Nielsen, J. Eric

    2006-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the TOMS and OMI instruments. The severity of the hole has been assessed using the minimum total ozone value from the October monthly mean (depth of the hole), the average size during the September-October period, and the ozone mass deficit. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. We use two methods to estimate ozone hole recovery. First, we use projections of halogen levels combined with age-of-air estimates in a parametric model. Second, we use a coupled chemistry climate model to assess recovery. We find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. Furthermore, full recovery to 1980 levels will not occur until approximately 2068. We will also show some error estimates of these dates and the impact of climate change on the recovery.

  9. Hydrocarbon degradation by Antarctic coastal bacteria

    Cavanagh, J.E. [University of Tasmania, Hobart (Australia). Antarctic Cooperative Research Centre; CSIRO Div of Marine Research, Hobart (Australia); University of Tasmania, Hobart (Australia). Dept. of Agricultural Science; Nichols, P.D. [University of Tasmania, Hobart (Australia). Antarctic Cooperative Research Centre; CSIRO Div. of Marine Research, Hobart (Australia); Franzmann, P.D. [CSIRO Land and Water, Wembley (Australia); McMeekin, T.A. [University of Tasmania, Hobart (Australia). Antarctic Cooperative Research Centre

    1999-07-01

    Bacterial cultures obtained through selective enrichment of beach sand collected 60 days and one year after treatment of sites in a pilot oil spill trial conducted at Airport Beach, Vestfold Hills, East Antarctica, were examined for the ability to degrade n-alkanes and phenanthrene. The effects of different hydrocarbon mixtures (Special Antarctic Blend [SAB] and BP-Visco), (fish oil [orange roughy]) and inoculation of replicate sites with water from Organic Lake, (previously shown to contain hydrocarbon-degrading bacteria) on the indigenous microbial population, were examined. Of the cultures obtained, those from sites treated with SAB and BP-Visco degraded n-alkanes most consistently and typically to the greatest extent. Two mixed cultures obtained from samples collected at 60 days and two isolates obtained from these cultures extensively degraded phenanthrene. 1-Hydroxy-naphthoic acid formed the major phenanthrene metabolite. Lower levels of salicyclic acid, 1-naphthol, 1,4-naphthaquinone and phenanthrene 9-10 dihydrodiol were detected in extracts of phenanthrene grown cultures. This study shows that under laboratory conditions indigenous Antarctica bacteria can degrade n-alkanes and the more recalcitrant polycyclic aromatic hydrocarbon, phenanthrene. The enrichment of hydrocarbon degrading microorganisms in Antarctic ecosystems exposed to hydrocarbons, is relevant for the long term fate of hydrocarbon spills in this environment. (author)

  10. Interhemispheric coupling and warm Antarctic interglacials

    P. B. Holden

    2009-12-01

    Full Text Available Ice core evidence indicates that even though atmospheric CO2 concentrations did not exceed ~300 ppm at any point during the last 800 000 years, East Antarctica was at least ~3–4 °C warmer than pre-industrial (CO2 ~280 ppm in each of the last four interglacials. During the previous three interglacials, this anomalous warming was short lived (~3 000 years and apparently occurred before the completion of Northern Hemisphere deglaciation. Hereafter, we refer to these periods as "Warmer than Present Transients" (WPTs. We here present transient 800 kyr simulations using the intermediate complexity model GENIE-1 which suggest that WPTs could be explained as a consequence of the meltwater-forced slowdown of the Atlantic Meridional Overturning Circulation (AMOC during glacial terminations. It is well known that a slowed AMOC would increase southern Sea Surface Temperature (SST through the bipolar seesaw. Observational data supports this hypothesis, suggesting that the AMOC remained weak throughout the terminations preceding WPTs, strengthening rapidly at a time which coincides closely with peak Antarctic temperature. In order to investigate model and boundary condition uncertainty, we additionally present three ensembles of transient GENIE-1 simulations across Termination II (135 000 to 124 000 BP and three snapshot HadCM3 simulations at 130 000 Before Present (BP. These simulations together reproduce both the timing and magnitude of WPTs, and point to the potential importance of an albedo feedback associated with West Antarctic Ice Sheet (WAIS retreat.

  11. Chlorine Monoxide in the Antarctic Spring Stratosphere.

    Jaramillo-Ayerbe, Mauricio

    1988-06-01

    A series of observations of stratospheric chlorine monoxide (ClO) were carried out during the austral springs of 1986 and 1987 in McMurdo Station, Antarctica, as part of two experimental campaigns sent to investigate the seasonal decrease in ozone over the antarctic continent (the ozone "hole"). Measurements of the vertical distribution of ClO were obtained by high resolution ground-based emission spectroscopy at 278 GHz, using the Stony Brook mm-wave receiver. They show the presence of an anomalous layer of lower stratospheric ClO which is not observed at other latitudes. This anomalous layer is centered at ~20 km altitude and exhibits a pronounced diurnal variation, reaching a maximum at midday and disappearing at night. During the period of Sep. 20-24, 1987, the lower-stratospheric ClO had a maximum volume mixing ratio of 1.8_sp{+0cdot5}{ -0cdot9} ppbv. A normal ClO layer centered at ~36 km was also observed, with concentrations and diurnal behavior similar to those seen in tropical latitudes. These findings are evidence of anomalous chlorine chemistry taking place in the lower stratosphere during the antarctic spring, and indicate that increasing anthropogenic chlorine is a prime causative agent in the formation of the ozone hole.

  12. Widespread Antarctic glaciation during the Late Eocene

    Carter, Andrew; Riley, Teal R.; Hillenbrand, Claus-Dieter; Rittner, Martin

    2017-01-01

    Marine sedimentary rocks drilled on the southeastern margin of the South Orkney microcontinent in Antarctica (Ocean Drilling Program Leg 113 Site 696) were deposited between ∼36.5 Ma to 33.6 Ma, across the Eocene-Oligocene climate transition. The recovered rocks contain abundant grains exhibiting mechanical features diagnostic of iceberg-rafted debris. Sand provenance based on a multi-proxy approach that included petrographic analysis of over 275,000 grains, detrital zircon geochronology and apatite thermochronometry rule out local sources (Antarctic Peninsula or the South Orkney Islands) for the material. Instead the ice-transported grains show a clear provenance from the southern Weddell Sea region, extending from the Ellsworth-Whitmore Mountains of West Antarctica to the coastal region of Dronning Maud Land in East Antarctica. This study provides the first evidence for a continuity of widespread glacier calving along the coastline of the southern Weddell Sea embayment at least 2.5 million yrs before the prominent oxygen isotope event at 34-33.5 Ma that is considered to mark the onset of widespread glaciation of the Antarctic continent.

  13. Analysis hydrogeochemical cituation in the territories adjacent to the storage ponds "Svidovok"

    Scherstyuk N.P.

    2014-12-01

    Full Text Available Thehydrogeochemicalcomposition of surface and groundwater in the area adjacent to the pond-storage “Svidovok” (West Donbas was analyzed. The chemical types of surface and groundwater by the formula Kurlova were determined. The equilibriums with aluminosilicates and silicateswereconsidered.

  14. Influence of Inlet / Shoal Complex on Adjacent Shorelines via Inlet Sink Method

    2012-07-01

    placing dredged material onto adjacent beaches in moderate quantities (~200-500K cu yd) since the 1970 ’s (Dredging Information System (DIS...southward to Matanzas Inlet. Analysis of the ebb shoal volume change between surveys was made within a GIS framework using an area mask (Fig. 6

  15. 33 CFR 334.70 - Buzzards Bay, and adjacent waters, Mass.; danger zones for naval operations.

    2010-07-01

    ..., Mass.; danger zones for naval operations. 334.70 Section 334.70 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.70 Buzzards Bay, and adjacent waters, Mass.; danger zones for naval operations. (a)...

  16. Deformations and damage to buildings adjacent to deep excavations in soft soils

    Korff, M.

    2009-01-01

    The objective of this study is to gain insight into mechanisms of soil-structure interaction for buildings adjacent to deep excavations and to find a reliable method to design and monitor deep excavations in urban areas with soft soil conditions. The research focuses on typical Dutch conditions. The

  17. Antarctic and Lighting Technology%南极与照明科技

    郝洛西; 林怡; 徐俊丽; 曾堃; 崔哲

    2014-01-01

    Special natural environment and polar day and night phenomenon have a greater negative impact on the physical and mental health of expeditions .Based on Chinese 29th Antarctic scientific expedition , this paper proposes a design strategy according to the lighting environment characteristics of Antarctic station, which aims to integrate the visual effects , emotional effects and biological effects , to create a healthy lighting environment , also takes a preliminary outlook for the development of lighting environment and other areas in the Antarctic station .%南极特殊的自然环境和极昼极夜现象对于科考队员的身心健康产生了较大的负面影响。本文基于中国第29次南极科学考察,针对南极站区光环境特点,提出了相应的光环境设计策略,旨在整合光的视觉效应、情感作用及生物效应三方面,创造出健康的南极科考站区光环境,并对半导体照明科技在南极站区光环境的应用和其他领域的发展前景进行了初步的展望。

  18. Site-Specific Variability in the Chemical Diversity of the Antarctic Red Alga Plocamium cartilagineum

    Ryan M. Young

    2013-06-01

    Full Text Available Plocamium cartilagineum is a common red alga on the benthos of Antarctica and can be a dominant understory species along the western Antarctic Peninsula. Algae from this region have been studied chemically, and like “P. cartilagineum” from other worldwide locations where it is common, it is rich in halogenated monoterpenes, some of which have been implicated as feeding deterrents toward sympatric algal predators. Secondary metabolites are highly variable in this alga, both qualitatively and quantitatively, leading us to probe individual plants to track the possible link of variability to genetic or other factors. Using cox1 and rbcL gene sequencing, we find that the Antarctic alga divides into two closely related phylogroups, but not species, each of which is further divided into one of five chemogroups. The chemogroups themselves, defined on the basis of Bray-Curtis similarity profiling of GC/QqQ chromatographic analyses, are largely site specific within a 10 km2 area. Thus, on the limited geographical range of this analysis, P. cartilagineum displays only modest genetic radiation, but its secondary metabolome was found to have experienced more extensive radiation. Such metabogenomic divergence demonstrated on the larger geographical scale of the Antarctic Peninsula, or perhaps even continent-wide, may contribute to the discovery of cryptic speciation.

  19. Ocean-atmosphere exchange of organic carbon and CO2 surrounding the Antarctic Peninsula

    Ruiz-Halpern, S.; Calleja, M. Ll.; Dachs, J.; Del Vento, S.; Pastor, M.; Palmer, M.; Agustí, S.; Duarte, C. M.

    2014-05-01

    Exchangeable organic carbon (OC) dynamics and CO2 fluxes in the Antarctic Peninsula during austral summer were highly variable, but the region appeared to be a net sink for OC and nearly in balance for CO2. Surface exchangeable dissolved organic carbon (EDOC) measurements had a 43 ± 3 (standard error, hereafter SE) μmol C L-1 overall mean and represented around 66% of surface non-purgeable dissolved organic carbon (DOC) in Antarctic waters, while the mean concentration of the gaseous fraction of organic carbon (GOC H-1) was 46 ± 3 SE μmol C L-1. There was a tendency towards low fugacity of dissolved CO2 (fCO2-w) in waters with high chlorophyll a (Chl a) content and high fCO2-w in areas with high krill densities. However, such relationships were not found for EDOC. The depth profiles of EDOC were also quite variable and occasionally followed Chl a profiles. The diel cycles of EDOC showed two distinct peaks, in the middle of the day and the middle of the short austral dark period, concurrent with solar radiation maxima and krill night migration patterns. However, no evident diel pattern for GOC H-1 or CO2 was observed. The pool of exchangeable OC is an important and active compartment of the carbon budget surrounding the Antarctic Peninsula and adds to previous studies highlighting its importance in the redistribution of carbon in marine environments.

  20. Biodiversity and adaptive evolution of Antarctic notothenioid fishes

    Qianghua Xu

    2014-01-01

    Full Text Available The sea surrounding the Antarctic continent is one of the coldest regions in the world. It provides an environmentally unique and isolated “hotbed” for evolution to take place. In the past 30 million years, species of Perciform suborder Notothenioidei evolved and diversified from a benthic and temperate-water ancestor, and now dominate the fish fauna of the coldest ocean. Because of their distribution across temperature zones both inside and outside the Antarctic Polar Front, notothenioid fishes are regarded as excellent model organisms for exploring mechanisms of adaptive evolution, particularly cold adaptation. We first summarize research progress on the biodiversity of Antarctic fish and then review current findings on the peculiar biological characteristics of Antarctic notothenioids that evolved in response to a freezing environment. Research has revealed that extensive gene duplication and transcriptomic changes occurred during the adaptive radiation of notothenioid fish. Examples of highly duplicated genes in the Antarctic lineages include genes encoding hepcidin, and zona pellucida proteins, in addition to various retrotransposable elements. A few genes from Antarctic notothenioid fishes have been used as transgenes and demonstrated to be effective in making transgenic plants cold-hardy. In the coming years, the genomes of some Antarctic notothenioid species will be fully sequenced and the adaptive functions of duplicated genes will be further elucidated. Such studies will deepen our understanding of how genomes evolve in freezing environments, and provide an improved knowledge of molecular mechanisms of cold adaptation.

  1. Antarctic Crustal Thickness from Gravity Inversion

    Vaughan, A. P.; Kusznir, N. J.; Ferraccioli, F.; Jordan, T. A.

    2013-12-01

    Using gravity anomaly inversion, we have produced the first comprehensive regional maps of crustal thickness and oceanic lithosphere distribution for Antarctica and the Southern Ocean. We determine Moho depth, crustal basement thickness, continental lithosphere thinning (1-1/β) and ocean-continent transition location using a 3D spectral domain gravity inversion method, which incorporates a lithosphere thermal gravity anomaly correction. The continental lithosphere thinning distribution, used to define the initial thermal model temperature perturbation is derived from the gravity inversion and uses no a priori isochron information; as a consequence the gravity inversion method provides a prediction of ocean-continent transition location, which is independent of ocean isochron information. The gravity anomaly contribution from ice thickness is included in the gravity inversion, as is the contribution from sediments which assumes a compaction controlled sediment density increase with depth. Data used in the gravity inversion are elevation and bathymetry, free-air gravity anomaly, the most recent Bedmap2 ice thickness and bedrock topography compilation south of 60 degrees south (Fretwell et al., 2013) and relatively sparse constraints on sediment thickness. Our gravity inversion study predicts thick crust (> 45 km) under interior East Antarctica penetrated by narrow continental rifts that feature relatively thinner crust. The East Antarctic Rift System (EARS) is a major Permian to Cretaceous age rift system that appears to extend from the continental margin at the Lambert Rift to the South Pole region, a distance of 2500 km. This is comparable in scale to the well-studied East African rift system. Intermediate crustal thickness with an inferred linear rift fabric is predicted under Coates Land. An extensive region of either thick oceanic crust or highly thinned continental crust is predicted offshore Oates Land and north Victoria Land, and also off West Antarctica

  2. Quantifying Antarctic marine biodiversity: The SCAR-MarBIN data portal

    Griffiths, Huw J.; Danis, Bruno; Clarke, Andrew

    2011-03-01

    The documentation and analysis of broad-scale biological diversity requires modern databases. Here we describe the SCAR-Marine Biodiversity Information Network (SCAR-MarBIN) and demonstrate its value with a preliminary analysis of geographic patterns in species richness for a variety of marine taxa. SCAR-MarBIN is a web portal ( www.scarmarbin.be) that compiles and manages existing and new information on Antarctic marine biodiversity; it currently links over 140 datasets comprising over one million records. The portal is home to the Registry of Antarctic Marine Species (RAMS), an authoritative taxonomic list of marine species occurring in Antarctica. RAMS is a key resource for the Census of Antarctic Marine Life (CAML), a major five-year project that aims at assessing the nature, distribution and abundance of Southern Ocean biological diversity. SCAR-MarBIN provides a means of quantifying not only the diversity and distribution of Antarctic marine life but also a record of how, when and where these have been studied. It allows for the examination of geographic and bathymetric ranges, the documentation of gaps within and limits to the data, together with the identification of areas of particularly high diversity (hotspots) and also under-sampled regions or taxa. A preliminary analysis indicates that the pattern of sampling hotspots is driven principally by the pelagic data, mainly bird and mammal observations, whereas benthic species drive the overall pattern in species richness. Analyses of the complete data set reveal important biases in the data: most samples have been taken in shallow water (deep sea and the Amundsen Sea.

  3. Toxicity of fuel-contaminated soil to Antarctic moss and terrestrial algae.

    Nydahl, Anna C; King, Catherine K; Wasley, Jane; Jolley, Dianne F; Robinson, Sharon A

    2015-09-01

    Fuel pollution is a significant problem in Antarctica, especially in areas where human activities occur, such as at scientific research stations. Despite this, there is little information on the effects of petroleum hydrocarbons on Antarctic terrestrial biota. The authors demonstrate that the Antarctic mosses Bryum pseudotriquetrum, Schistidium antarctici, and Ceratodon purpureus, and the Antarctic terrestrial alga Prasiola crispa are relatively tolerant to Special Antarctic Blend (SAB) fuel-contaminated soil (measured as total petroleum hydrocarbons). Freshly spiked soils were more toxic to all species than were aged soils containing degraded fuel, as measured by photosynthetic efficiency (variable fluorescence/maximum fluorescence [Fv/Fm]), pigment content, and visual observations. Concentrations that caused 20% inhibition ranged from 16,600 mg/kg to 53,200 mg/kg for freshly spiked soils and from 30,100 mg/kg to 56,200 mg/kg for aged soils. The photosynthetic efficiency of C. purpureus and S. antarctici was significantly inhibited by exposure to freshly spiked soils with lowest-observed-effect concentrations of 27,900 mg/kg and 40,400 mg/kg, respectively. Prasiola crispa was the most sensitive species to freshly spiked soils (Fv/Fm lowest-observed-effect concentration 6700 mg/kg), whereas the Fv/Fm of B. pseudotriquetrum was unaffected by exposure to SAB fuel even at the highest concentration tested (62,900 mg/kg). Standard toxicity test methods developed for nonvascular plants can be used in future risk assessments, and sensitivity data will contribute to the development of remediation targets for petroleum hydrocarbons to guide remediation activities in Antarctica.

  4. Multiple 'Stable' States of Antarctic Intermediate Water: A Study from the Subantarctic South-West Atlantic.

    Roberts, J.; Hodell, D. A.; Peck, V. L.; Kender, S.

    2014-12-01

    Modelling studies suggest that density changes in Antarctic Intermediate Water (AAIW) played a significant role in the reorganisation of Atlantic Meridional Overturning Circulation over the last glacial period. From its principal site of formation in the SE Pacific, a significant proportion of AAIW is entrained in the Antarctic circumpolar current and enters the Atlantic through Drake Passage. Air-sea interaction within the subAntarctic SW Atlantic modifies this AAIW further, producing a cooler and fresher Atlantic end member of AAIW. Our core site is located where this branch of AAIW subducts and travels northwards along the western margin of the Atlantic basin. We present the first high-resolution, multi-proxy study of AAIW in the sub-Antarctic SW Atlantic over the last 140 kyrs. Here, we focus on the temperature and salinity records over the last two glacial terminations and at the onset of the last glaciation. We use a combination of benthic stable isotopes and elemental ratios (Mg/Ca) on the shallow infaunal species Uvigerina peregrina to reconstruct AAIW temperature and salinity. Our records suggest that AAIW temperature both increased and decreased in a step-wise manner over the last 120 kyrs hinting at 3 'stable' states for AAIW through the last glacial cycle (see shaded areas within figure). Another common feature is a transient interval of apparently warm, saline AAIW observed at the onset of both glacial terminations - could this be evidence of the 'deep, salty blob' or of increased outflow of Pacific surface waters? We identify some fundamental differences between termination I and termination II; AAIW appears to have been markedly warmer during MIS6 than at the LGM. Furthermore, the glacial-interglacial potential density difference is much greater over termination I than termination II.

  5. Ecological niche modeling of sympatric krill predators around Marguerite Bay, Western Antarctic Peninsula

    Friedlaender, Ari S.; Johnston, David W.; Fraser, William R.; Burns, Jennifer; Halpin, Patrick N.; Costa, Daniel P.

    2011-07-01

    Adélie penguins ( Pygoscelis adeliae), carabeater seals ( Lobodon carcinophagus), humpback ( Megaptera novaeangliae), and minke whales ( Balaenoptera bonaernsis) are found in the waters surrounding the Western Antarctic Peninsula. Each species relies primarily on Antarctic krill ( Euphausia superba) and has physiological constraints and foraging behaviors that dictate their ecological niches. Understanding the degree of ecological overlap between sympatric krill predators is critical to understanding and predicting the impacts on climate-driven changes to the Antarctic marine ecosystem. To explore ecological relationships amongst sympatric krill predators, we developed ecological niche models using a maximum entropy modeling approach (Maxent) that allows the integration of data collected by a variety of means (e.g. satellite-based locations and visual observations). We created spatially explicit probability distributions for the four krill predators in fall 2001 and 2002 in conjunction with a suite of environmental variables. We find areas within Marguerite Bay with high krill predator occurrence rates or biological hot spots. We find the modeled ecological niches for Adélie penguins and crabeater seals may be affected by their physiological needs to haul-out on substrate. Thus, their distributions may be less dictated by proximity to prey and more so by physical features that over time provide adequate access to prey. Humpback and minke whales, being fully marine and having greater energetic demands, occupy ecological niches more directly proximate to prey. We also find evidence to suggest that the amount of overlap between modeled niches is relatively low, even for species with similar energetic requirements. In a rapidly changing and variable environment, our modeling work shows little indication that krill predators maintain similar ecological niches across years around Marguerite Bay. Given the amount of variability in the marine environment around the

  6. Evaluation of soil bioremediation techniques in an aged diesel spill at the Antarctic Peninsula.

    de Jesus, Hugo E; Peixoto, Raquel S; Cury, Juliano C; van Elsas, Jan D; Rosado, Alexandre S

    2015-12-01

    Many areas on the Antarctic continent already suffer from the direct and indirect influences of human activities. The main cause of contamination is petroleum hydrocarbons because this compound is used as a source of energy at the many research stations around the continent. Thus, the current study aims to evaluate treatments for bioremediation (biostimulation, bioaugmentation, and bioaugmentation + biostimulation) using soils from around the Brazilian Antarctic Station "Comandante Ferraz" (EACF), King George Island, Antarctic Peninsula. The experiment lasted for 45 days, and at the end of this period, chemical and molecular analyses were performed. Those analyses included the quantification of carbon and nitrogen, denaturing gradient gel electrophoresis (DGGE) analysis (with gradient denaturation), real-time PCR, and quantification of total hydrocarbons and polyaromatics. Molecular tests evaluated changes in the profile and quantity of the rrs genes of archaea and bacteria and also the alkB gene. The influence of the treatments tested was directly related to the type of soil used. The work confirmed that despite the extreme conditions found in Antarctic soils, the bacterial strains degraded hydrocarbons and bioremediation treatments directly influenced the microbial communities present in these soils even in short periods. Although the majority of the previous studies demonstrate that the addition of fertilizer seems to be most effective at promoting bioremediation, our results show that for some conditions, autochthonous bioaugmentation (ABA) treatment is indicated. This work highlights the importance of understanding the processes of recovery of contaminated environments in polar regions because time is crucial to the soil recovery and to choosing the appropriate treatment.

  7. Invited review: climate change impacts in polar regions: lessons from Antarctic moss bank archives.

    Royles, Jessica; Griffiths, Howard

    2015-03-01

    Mosses are the dominant plants in polar and boreal regions, areas which are experiencing rapid impacts of regional warming. Long-term monitoring programmes provide some records of the rate of recent climate change, but moss peat banks contain an unrivalled temporal record of past climate change on terrestrial plant Antarctic systems. We summarise the current understanding of climatic proxies and determinants of moss growth for contrasting continental and maritime Antarctic regions, as informed by 13C and 18O signals in organic material. Rates of moss accumulation are more than three times higher in the maritime Antarctic than continental Antarctica with growing season length being a critical determinant of growth rate, and high carbon isotope discrimination values reflecting optimal hydration conditions. Correlation plots of 13C and 18O values show that species (Chorisodontium aciphyllum / Polytrichum strictum) and growth form (hummock / bank) are the major determinants of measured isotope ratios. The interplay between moss growth form, photosynthetic physiology, water status and isotope composition are compared with developments of secondary proxies, such as chlorophyll fluorescence. These approaches provide a framework to consider the potential impact of climate change on terrestrial Antarctic habitats as well as having implications for future studies of temperate, boreal and Arctic peatlands. There are many urgent ecological and environmental problems in the Arctic related to mosses in a changing climate, but the geographical ranges of species and life-forms are difficult to track individually. Our goal was to translate what we have learned from the more simple systems in Antarctica, for application to Arctic habitats.

  8. Climate Model Dependency and Understanding the Antarctic Ice Sheet during the Warm Late Pliocene

    Dolan, Aisling; de Boer, Bas; Bernales, Jorge; Hunter, Stephen; Haywood, Alan

    2016-04-01

    In the context of future climate change, understanding the nature and behaviour of ice sheets during warm intervals of Earth history is fundamentally important. A warm period in the Late Pliocene (3.264 to 3.025 million years before present) can serve as a potential analogue for projected future climates. Although Pliocene ice locations and extents are still poorly constrained, a significant contribution to sea-level rise should be expected from both the Greenland ice sheet and the West and East Antarctic ice sheets based on palaeo sea-level reconstructions and geological evidence. Following a five year international project PLISMIP (Pliocene Ice Sheet Modeling Intercomparison Project) we present the final set of results which quantify uncertainty in climate model-based predictions of the Antarctic ice sheet. In this study we use an ensemble of climate model forcings within a multi-ice sheet model framework to assess the climate (model) dependency of large scale features of the Antarctic ice sheet. Seven coupled atmosphere-ocean climate models are used to derive surface temperature, precipitation and oceanic forcing that drive three ice sheet models (over the grounded and floating domain). Similar to results presented over Greenland, we show that the reconstruction of the Antarctic ice sheet is sensitive to which climate model is used to provide the forcing field. Key areas of uncertainty include West Antarctica, the large subglacial basins of East Antarctica and the overall thickness of the continental interior of East Antarctica. We relate the results back to geological proxy data, such as those relating to exposure rates which provide information on potential ice sheet thickness. Finally we discuss as to whether the choice of modelling framework (i.e. climate model and ice sheet model used) or the choice of boundary conditions causes the greatest uncertainty in ice sheet reconstructions of the warm Pliocene.

  9. The impacts of local human activities on the Antarctic environment

    Tin, T.; Fleming, Z. L.; Hughes, K. A.; Ainley, D. G.; Convey, P.; Moreno, C. A.; Pfeiffer, S.; Scott, J.; Snape, I.

    2009-04-01

    An overview of a recently published review of the scientific literature from the past decade on the impacts of human activities on the Antarctic environment is presented. An assessment of the cumulative effects of scientists and accompanying base construction, tourists and fishery activities in Antarctica is timely given a decade since the Protocol on Environmental Protection to the Antarctic Treaty came into force in 1998 and the increasing attention given to and human presence in Antarctica during this 2007-2009 IPY. A range of impacts has been identified at a variety of spatial and temporal scales. Chemical contamination and sewage disposal on the continent have been found to be long-lived, with contemporary sewage management practices at many coastal stations insufficient to prevent local contamination. Human activities, particularly construction and transport, have affected Antarctic flora and fauna and a small number of non-indigenous plant and animal species has become established on some of the Antarctic Peninsula and sub Antarctic islands. There is little indication of recovery of overexploited fish stocks, and ramifications of fishing activity on bycatch species and the ecosystem could also be far-reaching. The Antarctic Treaty System and its instruments, in particular the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) and the Environmental Protocol, provide a framework within which management of human activities take place. In order to ensure comprehensive protection of the Antarctic environment, including its intrinsic, wilderness and scientific values in the face of the continuing expansion of human activities in Antarctica, a more effective implementation of a wide range of measures is essential. These include effective environmental impact assessments, long-term monitoring, mitigation measures for non-indigenous species, ecosystem-based management of living resources, and increased regulation of National Antarctic

  10. Antarctic Treaty Summit to Focus on Global Science Policy Lessons

    Berkman, Paul Arthur; Walton, David W. H.; Weiler, C. Susan

    2008-10-01

    The Antarctic Treaty Summit, which will coincide with the fiftieth anniversary of the treaty's signing, will be held at the Smithsonian Institution's National Museum of Natural History, in Washington, D. C., from 30 November to 3 December 2009. The summit will provide an open international forum for scientists, legislators, lawyers, administrators, educators, students, corporate executives, historians, and other members of global civil society to explore science policy achievements from the first 50 years of the Antarctic Treaty. In addition, the summit will complement official government celebrations of the Antarctic Treaty anniversary that do not include public participation.

  11. ZOOGEOGRAPHICAL ZONING OF THE MEDITERRANEAN AND ADJACENT TERRITORIES

    H. A. Ketenchiev

    2013-01-01

    Full Text Available Abstract. Aim. The article considers the zoogeographical zoning of the Mediterranean and adjacent territories with the purpose of specification of the scheme of zoogeographic zoning of land on the basis of the distribution of dragonflies.Methods. Use common methods of entomological research, mapping and analysis of the fauna.Results. On the based on our analysis of the composition and distribution of odonatofauna Mediterranean zoogeographical subregion is offered to divide into 5 provinces: Caucasian, South-European, Pyrenees, Asian and African. Analysis of the existing schemes zoning of land based on the distribution of taxa dragonflies, installed the advantages and disadvantages presented by different authors, the result of which is proposed to change the borders between the Holarctic and Subholarctic areas of the Boreal fauna Kingdom (BFK. It is connected with the fact that the dividing them into subdomains and evaluation role in the establishment of regional odonatofauna not always convincing. In this regard, the article proposed to abolish the Holarctic region sub-region: European and Mongolian-Kazakh, and in Subholarctic - add 1 sub-region of Central Asia. In a new form Subholarctic region becomes clear and logical configuration, but her name becomes inadequate, therefore, we re-name it in Paleosubtropical.The scope of the results. In fundamental research on systematics of animals, ecology and biogeography.Main conclusions. Based on the study of the composition and distribution of taxa of dragonflies in the Mediterranean and adjacent territories proposed the division of the Mediterranean subregion 5 provinces and refined scheme of zoogeographic zoning of land.

  12. Eight Million Years of Land-Based Antarctic Ice Sheet Stability Recorded By In Situ 10Be from the ANDRILL-1B Core

    Shakun, J. D.; Corbett, L. B.; Bierman, P. R.

    2015-12-01

    The response of the East Antarctic Ice Sheet (EAIS) to Pliocene warmth provides a critical way to gauge its sensitivity to climate change. Considerable uncertainty surrounds the Pliocene behavior of the EAIS, however. For instance, global sea level estimates for the mid-Pliocene warm period range from 30 m, and numerous cosmogenic nuclide and sedimentological studies from the Transantarctic Mountains imply extreme landscape stability over the last several Myr whereas ocean records suggest orbital-scale instability of at least marine-based sectors of the ice sheet. These stabilist versus dynamicist views are difficult to resolve because onshore records are generally biased toward intervals of expanded ice cover and limited to areas with exposed land, while marine sediments typically provide indirect evidence for conditions on land and cannot distinguish between marine versus land-based ice sheet collapse. The AND-1B marine sediment core drilled beneath the Ross Ice Shelf contains a remarkably complete late Cenozoic sequence of glacial diamictons sourced from the adjacent EAIS, intercalated with open-water sediments likely associated with West Antarctic Ice Sheet collapse. We measured concentrations of in situ 10Be - produced only when ice cover is reduced and the landscape is exposed - in eight samples of glacially-derived quartz sand from AND-1B spanning parts of the last 8 Myr. Decay-corrected concentrations are low and show a long-term decline from 13,000 atoms/g to 1000 atoms/g over the record. These low values and the monotonic trend suggest that land-based ice sheet sectors have experienced little, if any, exposure during the past 8 Myr; the 10Be concentrations we measured are equivalent to only centuries or a few kyr of surface exposure. Perhaps more likely, the small quantities of 10Be were produced prior to the establishment of a full EAIS in the mid-Miocene, and reflect deeply-exhumed and thus 10Be-poor material that has been radioactively decaying beneath

  13. Different adaptations of Chinese winter-over expeditioners during prolonged Antarctic and sub-Antarctic residence.

    Chen, Nan; Wu, Quan; Li, Hao; Zhang, Tao; Xu, Chengli

    2016-05-01

    Prolonged residence in Antarctica is characterized by exposure to isolated, confined, and extreme (ICE) environment. Winter-over expeditioners at research stations often exhibit a complex of psychophysiological symptoms, which varied by stations and sociocultural backgrounds. To understand the different patterns of psychophysiological responses provoked by environmental stress, we conducted a longitudinal assessment of mood and endocrine function in two groups of Chinese expeditioners who were deployed to sub-Antarctic (Great Wall Station, 62°S, N = 12) and Antarctic (Zhongshan Station, 66°S, N = 16) from December 2003 to 2005. Measures of mood, thyroid function, the levels of plasma catecholamine, and circulating interleukins were obtained at departure from China, mid-winter (Antarctica), end of winter (Antarctica), and return to China, respectively. The Zhongshan Station crew experienced significant increases in fatigue, anger, tension, confusion, and decrease in free thyroxine (FT4), norepinephrine (NE), and epinephrine (E) during the winter, increase in thyrotropin (TSH) and total triiodothyronine (TT3) when returning, whereas their counterparts at Great Wall Station only experienced increased TT3 after deployment. Moreover, compared with the Great Wall Station crew, the Zhongshan Station crew exhibited greater increase in anger, greater decrease in FT4, total thyroxine (TT4), NE and E over the winter, and greater increase in TSH when returning. Chinese expeditioners who lived and worked at the Antarctic station and the sub-Antarctic station for over a year showed different change patterns in mood and endocrine hormones. Negative mood and endocrine dysfunction were positively associated with the severity of environment. The study is a supplement to scientific knowledge on psychophysiological variation under ICE environment, which has certain applied value for the development of preventive countermeasures or interventions.

  14. Different adaptations of Chinese winter-over expeditioners during prolonged Antarctic and sub-Antarctic residence

    Chen, Nan; Wu, Quan; Li, Hao; Zhang, Tao; Xu, Chengli

    2016-05-01

    Prolonged residence in Antarctica is characterized by exposure to isolated, confined, and extreme (ICE) environment. Winter-over expeditioners at research stations often exhibit a complex of psychophysiological symptoms, which varied by stations and sociocultural backgrounds. To understand the different patterns of psychophysiological responses provoked by environmental stress, we conducted a longitudinal assessment of mood and endocrine function in two groups of Chinese expeditioners who were deployed to sub-Antarctic (Great Wall Station, 62°S, N = 12) and Antarctic (Zhongshan Station, 66°S, N = 16) from December 2003 to 2005. Measures of mood, thyroid function, the levels of plasma catecholamine, and circulating interleukins were obtained at departure from China, mid-winter (Antarctica), end of winter (Antarctica), and return to China, respectively. The Zhongshan Station crew experienced significant increases in fatigue, anger, tension, confusion, and decrease in free thyroxine (FT4), norepinephrine (NE), and epinephrine (E) during the winter, increase in thyrotropin (TSH) and total triiodothyronine (TT3) when returning, whereas their counterparts at Great Wall Station only experienced increased TT3 after deployment. Moreover, compared with the Great Wall Station crew, the Zhongshan Station crew exhibited greater increase in anger, greater decrease in FT4, total thyroxine (TT4), NE and E over the winter, and greater increase in TSH when returning. Chinese expeditioners who lived and worked at the Antarctic station and the sub-Antarctic station for over a year showed different change patterns in mood and endocrine hormones. Negative mood and endocrine dysfunction were positively associated with the severity of environment. The study is a supplement to scientific knowledge on psychophysiological variation under ICE environment, which has certain applied value for the development of preventive countermeasures or interventions.

  15. Sensitivity of ocean circulation and sea-ice conditions to loss of West Antarctic ice shelves and ice sheet

    Bougamont, Marion; Hunke, Elizabeth C.; Tulaczyk, Slawek

    We use a global coupled ocean-sea ice model to test the hypothesis that the disintegration of the West Antarctic ice sheet (WAIS), or just its ice shelves, may modify ocean circulation and sea-ice conditions in the Southern Ocean. We compare the results of three model runs: (1) a control run with a standard (modern) configuration of landmask in West Antarctica, (2) a no-shelves run with West Antarctic ice shelves removed and (3) a no-WAIS run. In the latter two runs, up to a few million square kilometres of new sea surface area opens to sea-ice formation, causing the volume and extent of Antarctic sea-ice cover to increase compared with the control run. In general, near-surface waters are cooler around Antarctica in the no-shelves and no-WAIS model runs than in the control run, while warm intermediate and deep waters penetrate further south, increasing poleward heat transport. Varying regional responses to the imposed changes in landmask configuration are determined by the fact that Antarctic polynyas and fast ice develop in different parts of the model domain in each run. Model results suggest that changes in the extent of WAIS may modify oceanographic conditions in the Southern Ocean.

  16. Resistance to UV-B induced DNA damage in extreme-tolerant cryptoendolithic Antarctic fungi: detection by PCR assays.

    Selbmann, Laura; Isola, Daniela; Zucconi, Laura; Onofri, Silvano

    2011-10-01

    Cryptoendolithic Antarctic black fungi are adapted to the harshest terrestrial conditions as in the ice-free area of the McMurdo Dry Valleys. Recently, surviving space simulated conditions proves their bewildering extremotolerance. In order to investigate the potential DNA damage and their response after UV-B exposition, two strains of Antarctic cryptoendolithic black fungi, Cryomyces antarcticus CCFEE 534 and Cryomyces minteri CCFEE 5187, were irradiated at different UV-B doses. Since conventional methods cannot be applied to these organisms, the effect on the genome was assessed by RAPD and rDNA amplification PCR based assays; the results were compared with the responses of Saccharomyces pastorianus DBVPG 6283 treated with the same conditions. Results showed that template activity was drastically inhibited in S. pastorianus after irradiation. Dramatic changes in the RAPD profiles showed after 30 min of exposure while the rDNA amplification of SSU, LSU, and ITS portions failed after 30, 60, and 90 min of exposure respectively. No alteration was detected in the templates of the Antarctic strains where both RAPD profiles and rDNA PCR amplifications were unaffected even after 240 min of exposure. The electroferograms of the rDNA portions of Cryomyces strains were perfectly readable and conserved whilst the analyses revealed a marked alteration in S. pastorianus confirming the high resistance of the Antarctic strains to UV-B exposure.

  17. Analysis of adjacent segment reoperation after lumbar total disc replacement

    Rainey, Scott; Blumenthal, Scott L.; Zigler, Jack E.; Guyer, Richard D.; Ohnmeiss, Donna D.

    2012-01-01

    Background Fusion has long been used for treating chronic back pain unresponsive to nonoperative care. However, potential development of adjacent segment degeneration resulting in reoperation is a concern. Total disc replacement (TDR) has been proposed as a method for addressing back pain and preventing or reducing adjacent segment degeneration. The purpose of the study was to determine the reoperation rate at the segment adjacent to a level implanted with a lumbar TDR and to analyze the pre-...

  18. PIV Measurements and Mechanisms of Adjacent Synthetic Jets Interactions

    LUO Zhen-Bing; XIA Zhi-Xun

    2008-01-01

    Interactions of adjacent synthetic jet actuators with varying relative amplitude and the relative phase of driving voltage are measured using a particle image velocimetry(PIV).Varying relative amplitude or relative phase of driving voltage of the adjacent actuators vectors the direction of the ensuing merged jet of the adjacent synthetic jets.The vectoring mechanism of the adjacent vortex pairs,attract-impact causing deflection(AICD),is provided to explain why the merged jet is generally vectored to the side of the phase-leading synthetic jet or the synthetic jet with higher driving voltage.

  19. Study on the distribution and developmental environment of the Late Paleozoic volcanoes in Junggar Basin and its adjacent areas%准噶尔盆地及其周缘地区晚古生代火山机构分布与发育环境分析

    毛翔; 李江海; 张华添; 王洛

    2012-01-01

    and Xiayan uplift). The volcanoes inside the basin are principally controlled by Hercynian fault systems, along NE and near EW trending faults and most developed in the interjunctions of the faults. The modification by late-stage weathering and leaching made the volcanoes difficult to identify. Remaining volcanic landforms, changing trends of the volcanic lithofacies and the typical volcanic rock, such as the crypto-explosive breccia, are the typical marks of the Late Paleozoic volcanoes in the field; and the concealed volcanic edifices are identified by the techniques of seismic identification, such as seismic slicing, analysis of the attribute and tectonic trend plane. The ages of the volcanic rocks are focused on from 340Ma to 320Ma and from 300Ma to 295Ma,corresponding to the subducting periods of West Junggar and East Junggar. From Early Carboniferous to Late Carboniferous, the volcanic activities in Junggar Basin and its adjacent areas show a variation trend from undersea to continental, from deep water to shallow water and from continental margin to intracontinental.

  20. Small vulvar squamous cell carcinomas and adjacent tissues. A morphologic study

    Poulsen, Hemming; Junge, Jette; Vyberg, Mogens;

    2003-01-01

    Vulvar squamous cell carcinomas are of different subtypes and degrees of differentiation, and may be associated with adjacent lichen sclerosus and/or varying degrees of dysplasia. The aim of this investigation was to study small carcinomas with a diameter of less than 2 cm in order to find...... a possible relation between subtypes of carcinomas and adjacent epithelial changes. Fourteen cases of small vulvar squamous cell carcinomas were totally embedded in paraffin. Serial sectioning made a detailed mapping of all different lesions possible, and a two- and three-dimensional imaging was obtained...... in each case. Seven patients with keratinizing squamous cell carcinomas (median age 65) had adjacent lichen sclerosus. All carcinomas were completely surrounded by areas of VIN1. VIN2 and VIN3 were not found. Seven patients without lichen sclerosus (median age 58) showed squamous cell carcinomas...

  1. Marine and terrestrial factors affecting Adélie penguin Pygoscelis adeliae chick growth and recruitment off the western Antarctic Peninsula

    Chapman, Erik W.; Hofmann, Eileen E.; Patterson, Donna L.; Ribic, Christine A.; Fraser, William R.

    2011-01-01

    An individual-based bioenergetics model that simulates the growth of an Adélie penguin Pygoscelis adeliaechick from hatching to fledging was used to assess marine and terrestrial factors that affect chick growth and fledging mass off the western Antarctic Peninsula. Simulations considered the effects on Adélie penguin fledging mass of (1) modification of chick diet through the addition of Antarctic silverfish Pleuragramma antarcticum to an all-Antarctic krillEuphausia superba diet, (2) reduction of provisioning rate which may occur as a result of an environmental stress such as reduced prey availability, and (3) increased thermoregulatory costs due to wetting of chicks which may result from increased precipitation or snow-melt in colonies. Addition of 17% Antarctic silverfish of Age-Class 3 yr (AC3) to a penguin chick diet composed of Antarctic krill increased chick fledging mass by 5%. Environmental stress that results in >4% reduction in provisioning rate or wetting of just 10% of the chick’s surface area decreased fledging mass enough to reduce the chick’s probability of successful recruitment. The negative effects of reduced provisioning and wetting on chick growth can be compensated for by inclusion of Antarctic silverfish of AC3 and older in the chick diet. Results provide insight into climate-driven processes that influence chick growth and highlight a need for field research designed to investigate factors that determine the availability of AC3 and older Antarctic silverfish to foraging Adélie penguins and the influence of snowfall on chick wetting, thermoregulation and adult provisioning rate.

  2. Photosynthesis in a sub-Antarctic shore-zone lichen

    Smith, V.; Gremmen, N.J.M.

    2001-01-01

    Photosynthetic responses to moisture, light, temperature, salinity and inorganic nitrogen fertilization are reported for a shore-zone lichen Turgidiusculum complicatulum (formerly Mastodia tesselata), a possible recent introduction to sub-Antarctic Marion Island. Optimum moisture contents for net ph

  3. German Antarctic Receiving Station (GARS) O'Higgins

    Neidhardt, Alexander; Ploetz, Christian; Kluegel, Thomas

    2013-01-01

    In 2012, the German Antarctic Receiving Station (GARS) O'Higgins contributed to the IVS observing program with four observation sessions. Maintenance and upgrades were made, and a new replacement dewar is under construction in the observatory at Yebes, Spain.

  4. Climate Prediction Center (CPC) Daily Antarctic Oscillation Index

    National Oceanic and Atmospheric Administration, Department of Commerce — The Antarctic Oscillation (AAO) is a leading teleconnection pattern in the Southern Hemisphere circulation. It is calculated as the first Empirical Orthogonal...

  5. Climate Prediction Center(CPC)Monthly Antarctic Oscillation Index

    National Oceanic and Atmospheric Administration, Department of Commerce — The Antarctic Oscillation (AAO) is a leading teleconnection pattern in the Southern Hemisphere circulation. It is calculated as the first Empirical Orthogonal...

  6. Organic analysis of the Antarctic carbonaceous chondrites

    Kotra, R. K.; Shimoyama, A.; Ponnamperuma, C.; Hare, P. E.; Yanai, K.

    1981-01-01

    Thus far, organic analysis of carbonaceous chondrites has proven the only fruitful means of examining complex organic matter of extraterrestrial origin. The present paper presents the results of organic analysis of two Antarctic meteorites, Allan Hills (77306) and Yamato (74662), which may be considered free from terrestrial contamination. Ion-exchange chromatography, gas chromatography and mass spectrometery of meteorite samples reveal the presence in Yamato of 15 and in Allan Hills of 20 protein and nonprotein amino acids, the most abundant of which are glycine and alanine. Abundances of the D and L enantiomers of each amino acid are also found to be nearly equal. Data thus indicate an abiotic extraterrestrial origin for the matter, and confirm a lack of terrestrial contamination.

  7. An Antarctic molluscan biomineralisation tool-kit

    Sleight, Victoria A.; Marie, Benjamin; Jackson, Daniel J.; Dyrynda, Elisabeth A.; Marie, Arul; Clark, Melody S.

    2016-11-01

    The Antarctic clam Laternula elliptica lives almost permanently below 0 °C and therefore is a valuable and tractable model to study the mechanisms of biomineralisation in cold water. The present study employed a multidisciplinary approach using histology, immunohistochemistry, electron microscopy, proteomics and gene expression to investigate this process. Thirty seven proteins were identified via proteomic extraction of the nacreous shell layer, including two not previously found in nacre; a novel T-rich Mucin-like protein and a Zinc-dependent metalloprotease. In situ hybridisation of seven candidate biomineralisation genes revealed discrete spatial expression patterns within the mantle tissue, hinting at modular organisation, which is also observed in the mantle tissues of other molluscs. All seven of these biomineralisation candidates displayed evidence of multifunctionality and strong association with vesicles, which are potentially involved in shell secretion in this species.

  8. Joint Antarctic School Expedition - An International Collaboration for High School Students and Teachers on Antarctic Science

    Botella, J.; Warburton, J.; Bartholow, S.; Reed, L. F.

    2014-12-01

    The Joint Antarctic School Expedition (JASE) is an international collaboration program between high school students and teachers from the United States and Chile aimed at providing the skills required for establishing the scientific international collaborations that our globalized world demands, and to develop a new approach for science education. The National Antarctic Programs of Chile and the United States worked together on a pilot program that brought high school students and teachers from both countries to Punta Arenas, Chile, in February 2014. The goals of this project included strengthening the partnership between the two countries, and building relationships between future generations of scientists, while developing the students' awareness of global scientific issues and expanding their knowledge and interest in Antarctica and polar science. A big component of the project involved the sharing by students of the acquired knowledge and experiences with the general public. JASE is based on the successful Chilean Antarctic Science Fair developed by Chile´s Antarctic Research Institute. For 10 years, small groups of Chilean students, each mentored by a teacher, perform experimental or bibliographical Antarctic research. Winning teams are awarded an expedition to the Chilean research station on King George Island. In 2014, the Chileans invited US participation in this program in order to strengthen science ties for upcoming generations. On King George Island, students have hands-on experiences conducting experiments and learning about field research. While the total number of students directly involved in the program is relatively small, the sharing of the experience by students with the general public is a novel approach to science education. Research experiences for students, like JASE, are important as they influence new direction for students in science learning, science interest, and help increase science knowledge. We will share experiences with the

  9. Arctic and Antarctic sea ice and climate

    Barreira, S.

    2014-12-01

    Principal Components Analysis in T-Mode Varimax rotated was performed on Antarctic and Arctic monthly sea ice concentration anomalies (SICA) fields for the period 1979-2014, in order to investigate which are the main spatial characteristics of sea ice and its relationship with atmospheric circulation. This analysis provides 5 patterns of sea ice for inter-spring period and 3 patterns for summer-autumn for Antarctica (69,2% of the total variance) and 3 different patterns for summer-autumn and 3 for winter-spring season for the Arctic Ocean (67,8% of the total variance).Each of these patterns has a positive and negative phase. We used the Monthly Polar Gridded Sea Ice Concentrations database derived from satellite information generated by NASA Team algorithm. To understand the links between the SICA and climate trends, we extracted the mean pressure and, temperature field patterns for the months with high loadings (positive or negative) of the sea ice patterns that gave distinct atmospheric structures associated with each one. For Antarctica, the first SICA spatial winter-spring pattern in positive phase shows a negative SICA centre over the Drake Passage and north region of Bellingshausen and Weddell Seas together with another negative SICA centre over the East Indian Ocean. Strong positive centres over the rest of the Atlantic and Indian Oceans basins and the Amundsen Sea are also presented. A strong negative pressure anomaly covers most of the Antarctic Continent centered over the Bellingshausen Sea accompanied by three positive pressure anomalies in middle-latitudes. During recent years, the Arctic showed persistent associations of sea-ice and climate patterns principally during summer. Our strongest summer-autumn pattern in negative phase showed a marked reduction on SICA over western Arctic, primarily linked to an overall increase in Arctic atmospheric temperature most pronounced over the Beaufort, Chukchi and East Siberian Seas, and a positive anomaly of

  10. Depth and density of the Antarctic firn layer

    2008-01-01

    The depth and density of the Antarctic firn layer is modeled, using a combination of regional climate model output and a steady-state firn densification model. The modeled near-surface climate (temperature, wind speed, and accumulation) and the depth of two critical density levels (550 kg m−3 and 830 kg m−3) agree well with climate and firn density observations selected from >50 Antarctic coring sites (r = 0.90–0.99, p

  11. The present and future state of the Antarctic firn layer

    2014-01-01

    Firn is the transitional product between fresh snow and glacier ice and acts as a boundary between the atmosphere and the glacier ice of the Antarctic Ice Sheet (AIS). Spatiotemporal variations in firn layer characteristics are therefore important to consider when assessing the mass balance of the AIS. In this thesis, a firn densification model, forced with a realistic climate, is used to examine contemporary (1979-2012) and future (2000-2200) variations in the Antarctic firn layer. Currently...

  12. Antarctic marine biodiversity and deep-sea hydrothermal vents.

    Chown, Steven L

    2012-01-01

    The diversity of many marine benthic groups is unlike that of most other taxa. Rather than declining from the tropics to the poles, much of the benthos shows high diversity in the Southern Ocean. Moreover, many species are unique to the Antarctic region. Recent work has shown that this is also true of the communities of Antarctic deep-sea hydrothermal vents. Vent ecosystems have been documented from many sites across the globe, associated with the thermally and chemically variable habitats found around these, typically high temperature, streams that are rich in reduced compounds and polymetallic sulphides. The animal communities of the East Scotia Ridge vent ecosystems are very different to those elsewhere, though the microbiota, which form the basis of vent food webs, show less differentiation. Much of the biological significance of deep-sea hydrothermal vents lies in their biodiversity, the diverse biochemistry of their bacteria, the remarkable symbioses among many of the marine animals and these bacteria, and the prospects that investigations of these systems hold for understanding the conditions that may have led to the first appearance of life. The discovery of diverse and unusual Antarctic hydrothermal vent ecosystems provides opportunities for new understanding in these fields. Moreover, the Antarctic vents south of 60°S benefit from automatic conservation under the Convention on the Conservation of Antarctic Marine Living Resources and the Antarctic Treaty. Other deep-sea hydrothermal vents located in international waters are not protected and may be threatened by growing interests in deep-sea mining.

  13. Transcriptomics and comparative analysis of three antarctic notothenioid fishes.

    Seung Chul Shin

    Full Text Available For the past 10 to 13 million years, Antarctic notothenioid fish have undergone extraordinary periods of evolution and have adapted to a cold and highly oxygenated Antarctic marine environment. While these species are considered an attractive model with which to study physiology and evolutionary adaptation, they are poorly characterized at the molecular level, and sequence information is lacking. The transcriptomes of the Antarctic fishes Notothenia coriiceps, Chaenocephalus aceratus, and Pleuragramma antarcticum were obtained by 454 FLX Titanium sequencing of a normalized cDNA library. More than 1,900,000 reads were assembled in a total of 71,539 contigs. Overall, 40% of the contigs were annotated based on similarity to known protein or nucleotide sequences, and more than 50% of the predicted transcripts were validated as full-length or putative full-length cDNAs. These three Antarctic fishes shared 663 genes expressed in the brain and 1,557 genes expressed in the liver. In addition, these cold-adapted fish expressed more Ub-conjugated proteins compared to temperate fish; Ub-conjugated proteins are involved in maintaining proteins in their native state in the cold and thermally stable Antarctic environments. Our transcriptome analysis of Antarctic notothenioid fish provides an archive for future studies in molecular mechanisms of fundamental genetic questions, and can be used in evolution studies comparing other fish.

  14. Renewable Power for the Swedish Antarctic Station Wasa

    Henryson, Mattias; Svensson, Martin [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Energy Technology

    2004-07-01

    As the debate on fossil fuel usage in Antarctica has been more and more highlighted, the participating countries, bound by the Antarctic treaty, have encouraged changes in their power systems. Some of the stations or research stations in Antarctica are very large, constituting smaller towns with all conceivable service, and hence very energy consuming. Focus is put on partly or completely replacing fossil fuelled energy with renewable energy such as wind and solar power, supported by either batteries or fuel cells. Today there are a number of both successful and unsuccessful installations of renewable energy systems in Antarctica. Implementing a power system in remote areas where continuous access is limited comprises great technical challenges and Antarctica fulfils by all means every difficulty involved. The objective of this thesis is to propose ways of meeting power and energy demands for the Swedish Antarctic Research Program (SWEDARP) under the strict environmental legislations by as far as possible utilising the free renewable energy resources. A new power system is aimed at supplying 1 kW of electric power for continuous monitoring and collection of research data. The station is manned for three months, which implies a need of an autonomous system with high reliability. The following was based on a technical viability and economical feasibility study. Results are based upon analyses and computer simulations (HOMER) on how each fundamental system component is expected to work in the harsh climate conditions found at the station Wasa in Antarctica. It was found that wind power has the greatest potential as primary energy source in Antarctica. Supported by appropriate batteries, a reliable and in many ways feasible system can be obtained. Nevertheless, for the chosen techniques to endure the harsh climate conditions, sufficient modifications and developments of each component are needed. Based on the analyses the survey results in a proposal for a final system

  15. Super-aggregations of krill and humpback whales in Wilhelmina Bay, Antarctic Peninsula.

    Douglas P Nowacek

    Full Text Available Ecological relationships of krill and whales have not been explored in the Western Antarctic Peninsula (WAP, and have only rarely been studied elsewhere in the Southern Ocean. In the austral autumn we observed an extremely high density (5.1 whales per km(2 of humpback whales (Megaptera novaeangliae feeding on a super-aggregation of Antarctic krill (Euphausia superba in Wilhelmina Bay. The krill biomass was approximately 2 million tons, distributed over an area of 100 km(2 at densities of up to 2000 individuals m(-3; reports of such 'super-aggregations' of krill have been absent in the scientific literature for >20 years. Retentive circulation patterns in the Bay entrained phytoplankton and meso-zooplankton that were grazed by the krill. Tagged whales rested during daylight hours and fed intensively throughout the night as krill migrated toward the surface. We infer that the previously unstudied WAP embayments are important foraging areas for whales during autumn and, furthermore, that meso-scale variation in the distribution of whales and their prey are important features of this system. Recent decreases in the abundance of Antarctic krill around the WAP have been linked to reductions in sea ice, mediated by rapid climate change in this area. At the same time, baleen whale populations in the Southern Ocean, which feed primarily on krill, are recovering from past exploitation. Consideration of these features and the effects of climate change on krill dynamics are critical to managing both krill harvests and the recovery of baleen whales in the Southern Ocean.

  16. Potential extinction of Antarctic endemic fungal species as a consequence of global warming

    Selbmann, Laura, E-mail: selbmann@unitus.it [Department of Ecological and Biological Sciences (DEB), Universita degli Studi della Tuscia, Largo dell' Universita, 01100 Viterbo (Italy); Isola, Daniela; Fenice, Massimiliano; Zucconi, Laura [Department of Ecological and Biological Sciences (DEB), Universita degli Studi della Tuscia, Largo dell' Universita, 01100 Viterbo (Italy); Sterflinger, Katja [Department of Biotechnology, Austrian Center of Biological Resources and Applied Mycology (ACBR), University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien (Austria); Onofri, Silvano [Department of Ecological and Biological Sciences (DEB), Universita degli Studi della Tuscia, Largo dell' Universita, 01100 Viterbo (Italy)

    2012-11-01

    Cryomyces spp. are fungi adapted to the harsh conditions of the McMurdo Dry Valleys in the Antarctic. The structure of their cell wall is one of the main factors for their uncommon ability to survive external stressors. The cells are, in fact, embedded in a thick and strongly melanised cell wall encrusted with black rigid plaques giving a supplementary protection and making them practically impregnable and refractory even to commercial enzymes including chitinases and glucanases. The Antarctic fungus Lecanicillium muscarium CCFEE 5003, able to produce an arsenal of lytic enzymes, including chitinases and glucanases, is known for its ability to degrade the cell walls of different food spoiling and opportunistic fungi as well as plant pathogenic Oomycota. Active cells of Cryomyces spp. were cultivated in dual culture with the mycoparasitic fungus both in liquid and solid media. Light microscope observations revealed that the cell walls of Cryomyces were heavily decayed. This resulted in the release of protoplasts. Hyphae penetration was evident with both scanning and transmission electron microscope observations. Due to its ecological amplitude (i.e. temperature growth range 0-28 Degree-Sign C), the parasitic fungus could easily expand its area of distribution as a consequence of global warming by invading new areas towards the interior of the continent. The establishment of interactions with organisms living at present in border ecosystems may lead to extinction of extremely specialized and poorly competitive entities. -- Highlights: Black-Right-Pointing-Pointer We studied interactions among Antarctic fungi to evaluate the effects of global warming. Black-Right-Pointing-Pointer Cryomyces spp. was parasitized and killed by Lecanicillum muscarium in co-cultures. Black-Right-Pointing-Pointer L. muscarium lythic activities may have intriguing and new applications. Black-Right-Pointing-Pointer L. muscarium may expand its area of distribution as a consequence of global

  17. Calling in the cold: pervasive acoustic presence of humpback whales (Megaptera novaeangliae) in Antarctic coastal waters.

    Van Opzeeland, Ilse; Van Parijs, Sofie; Kindermann, Lars; Burkhardt, Elke; Boebel, Olaf

    2013-01-01

    Humpback whales migrate between relatively unproductive tropical or temperate breeding grounds and productive high latitude feeding areas. However, not all individuals of a population undertake the annual migration to the breeding grounds; instead some are thought to remain on the feeding grounds year-round, presumably to avoid the energetic demands of migration. In the Southern Hemisphere, ice and inclement weather conditions restrict investigations of humpback whale presence on feeding grounds as well as the extent of their southern range. Two years of near-continuous recordings from the PerenniAL Acoustic Observatory in the Antarctic Ocean (PALAOA, Ekström Iceshelf, 70°31'S, 8°13'W) are used to explore the acoustic presence of humpback whales in an Antarctic coastal area. Humpback whale calls were present during nine and eleven months of 2008 and 2009, respectively. In 2008, calls were present in January through April, June through August, November and December, whereas in 2009, calls were present throughout the year, except in September. Calls occurred in un-patterned sequences, representing non-song sound production. Typically, calls occurred in bouts, ranging from 2 to 42 consecutive days with February, March and April having the highest daily occurrence of calls in 2008. In 2009, February, March, April and May had the highest daily occurrence of calls. Whales were estimated to be within a 100 km radius off PALAOA. Calls were also present during austral winter when ice cover within this radius was >90%. These results demonstrate that coastal areas near the Antarctic continent are likely of greater importance to humpback whales than previously assumed, presumably providing food resources year-round and open water in winter where animals can breathe.

  18. Calling in the cold: pervasive acoustic presence of humpback whales (Megaptera novaeangliae in Antarctic coastal waters.

    Ilse Van Opzeeland

    Full Text Available Humpback whales migrate between relatively unproductive tropical or temperate breeding grounds and productive high latitude feeding areas. However, not all individuals of a population undertake the annual migration to the breeding grounds; instead some are thought to remain on the feeding grounds year-round, presumably to avoid the energetic demands of migration. In the Southern Hemisphere, ice and inclement weather conditions restrict investigations of humpback whale presence on feeding grounds as well as the extent of their southern range. Two years of near-continuous recordings from the PerenniAL Acoustic Observatory in the Antarctic Ocean (PALAOA, Ekström Iceshelf, 70°31'S, 8°13'W are used to explore the acoustic presence of humpback whales in an Antarctic coastal area. Humpback whale calls were present during nine and eleven months of 2008 and 2009, respectively. In 2008, calls were present in January through April, June through August, November and December, whereas in 2009, calls were present throughout the year, except in September. Calls occurred in un-patterned sequences, representing non-song sound production. Typically, calls occurred in bouts, ranging from 2 to 42 consecutive days with February, March and April having the highest daily occurrence of calls in 2008. In 2009, February, March, April and May had the highest daily occurrence of calls. Whales were estimated to be within a 100 km radius off PALAOA. Calls were also present during austral winter when ice cover within this radius was >90%. These results demonstrate that coastal areas near the Antarctic continent are likely of greater importance to humpback whales than previously assumed, presumably providing food resources year-round and open water in winter where animals can breathe.

  19. Super-aggregations of krill and humpback whales in Wilhelmina Bay, Antarctic Peninsula.

    Nowacek, Douglas P; Friedlaender, Ari S; Halpin, Patrick N; Hazen, Elliott L; Johnston, David W; Read, Andrew J; Espinasse, Boris; Zhou, Meng; Zhu, Yiwu

    2011-04-27

    Ecological relationships of krill and whales have not been explored in the Western Antarctic Peninsula (WAP), and have only rarely been studied elsewhere in the Southern Ocean. In the austral autumn we observed an extremely high density (5.1 whales per km(2)) of humpback whales (Megaptera novaeangliae) feeding on a super-aggregation of Antarctic krill (Euphausia superba) in Wilhelmina Bay. The krill biomass was approximately 2 million tons, distributed over an area of 100 km(2) at densities of up to 2000 individuals m(-3); reports of such 'super-aggregations' of krill have been absent in the scientific literature for >20 years. Retentive circulation patterns in the Bay entrained phytoplankton and meso-zooplankton that were grazed by the krill. Tagged whales rested during daylight hours and fed intensively throughout the night as krill migrated toward the surface. We infer that the previously unstudied WAP embayments are important foraging areas for whales during autumn and, furthermore, that meso-scale variation in the distribution of whales and their prey are important features of this system. Recent decreases in the abundance of Antarctic krill around the WAP have been linked to reductions in sea ice, mediated by rapid climate change in this area. At the same time, baleen whale populations in the Southern Ocean, which feed primarily on krill, are recovering from past exploitation. Consideration of these features and the effects of climate change on krill dynamics are critical to managing both krill harvests and the recovery of baleen whales in the Southern Ocean.

  20. Parasites of the Antarctic toothfish (Dissostichus mawsoni Norman, 1937 (Perciformes, Nototheniidae in the Pacific sector of the Antarctic

    Ilya I. Gordeev

    2016-06-01

    Full Text Available The Antarctic toothfish (Dissostichus mawsoni Norman, 1937 is one of the main target species of commercial fisheries in the Antarctic. It is an endemic and is found along the shelf of Antarctica, as well as on the slopes of seamounts, underwater elevations and islands in the sub-Antarctic. It feeds on a variety of fish and cephalopods and can be an intermediate/paratenic host of some helminthes, whose final hosts are whales, seals, large rays and sharks. This article presents new data on toothfish infection in the Pacific sector of the Antarctic. Specimens were examined during commercial longline fishing in the Ross Sea and the Amundsen Sea in January–February 2013. Fourteen species of parasites were found using standard parasitological methods and genetic analysis.

  1. Holocene glacier dynamics on James Ross Island, NE Antarctic Peninsula

    Davies, B. J.; Glasser, N. F.; Hambrey, M.

    2013-12-01

    The northern Antarctic Peninsula is currently warming very rapidly, which has resulted in ice sheet thinning, ice-shelf collapse, and rapid and widespread glacier recession. These small mountain glaciers are predicted to make a large sea level contribution over the coming century. Reconstructing past rates, volumes and magnitudes of change, particularly with respect to the former configuration of former ice sheets and ice shelves, is vital to contextualise contemporary change and to improve predictions of future ice-sheet behaviour. The aim of this research is therefore to investigate the relationship of deglacial ice sheet thinning and Holocene glacier fluctuations around James Ross Island, northeast Antarctic Peninsula, with temperature changes recorded in the Mount Haddington Ice Core. We use a combination of geomorphological mapping, from field campaigns and remotely sensed images, cosmogenic nuclide ages on glacially transported boulders, and numerical modelling with a simple 1D flowline model. Prior to 18 ka, James Ross Island was inundated by a thick and mainly cold-based ice sheet, which scattered granite erratics across the island. Ice sheet thickness and the rate of thinning is constrained by granite erratics on Terrapin Hill (610 m a.s.l.), and from flat-topped mesas at 370 m a.s.l. on Ulu Peninsula. During deglaciation and a period of rapid warming and eustatic sea level rise, the area was drained by Prince Gustav Ice Stream. The ice sheet reached its current configuration by around 6 ka, with glacier readvances around 4-5 ka. At Boulder Valley, near Terrapin Hill on James Ross Island, a large glacial readvance reached the current shoreline. It pre-dated the Mid-Holocene sea level high-stand, and has shorelines imprinted upon its seaward face. After 5.3 cal. ka BP and post-dating the mid-Holocene sea level high-stand, there was a readvance of at least 7 km by glacier 'IJR-45' on Ulu Peninsula. Rapid glacier recession occurred during a period of

  2. Future development of the PLATO Observatory for Antarctic science

    Ashley, Michael C. B.; Bonner, Colin S.; Everett, Jon R.; Lawrence, Jon S.; Luong-Van, Daniel; McDaid, Scott; McLaren, Campbell; Storey, John W. V.

    2010-07-01

    PLATO is a self-contained robotic observatory built into two 10-foot shipping containers. It has been successfully deployed at Dome A on the Antarctic plateau since January 2008, and has accumulated over 730 days of uptime at the time of writing. PLATO provides 0.5{1kW of continuous electrical power for a year from diesel engines running on Jet-A1, supplemented during the summertime with solar panels. One of the 10-foot shipping containers houses the power system and fuel, the other provides a warm environment for instruments. Two Iridium satellite modems allow 45 MB/day of data to be transferred across the internet. Future enhancements to PLATO, currently in development, include a more modular design, using lithium iron-phosphate batteries, higher power output, and a light-weight low-power version for eld deployment from a Twin Otter aircraft. Technologies used in PLATO include a CAN (Controller Area Network) bus, high-reliability PC/104 com- puters, ultracapacitors for starting the engines, and fault-tolerant redundant design.

  3. Recent advances in understanding Antarctic subglacial lakes and hydrology.

    Siegert, Martin J; Ross, Neil; Le Brocq, Anne M

    2016-01-28

    It is now well documented that over 400 subglacial lakes exist across the bed of the Antarctic Ice Sheet. They comprise a variety of sizes and volumes (from the approx. 250 km long Lake Vostok to bodies of water less than 1 km in length), relate to a number of discrete topographic settings (from those contained within valleys to lakes that reside in broad flat terrain) and exhibit a range of dynamic behaviours (from 'active' lakes that periodically outburst some or all of their water to those isolated hydrologically for millions of years). Here we critique recent advances in our understanding of subglacial lakes, in particular since the last inventory in 2012. We show that within 3 years our knowledge of the hydrological processes at the ice-sheet base has advanced considerably. We describe evidence for further 'active' subglacial lakes, based on satellite observation of ice-surface changes, and discuss why detection of many 'active' lakes is not resolved in traditional radio-echo sounding methods. We go on to review evidence for large-scale subglacial water flow in Antarctica, including the discovery of ancient channels developed by former hydrological processes. We end by predicting areas where future discoveries may be possible, including the detection, measurement and significance of groundwater (i.e. water held beneath the ice-bed interface).

  4. Direct linking of Greenland and Antarctic ice cores at the Toba eruption (74 ka BP

    A. Svensson

    2013-03-01

    Full Text Available The Toba eruption that occurred some 74 ka ago in Sumatra, Indonesia, is among the largest volcanic events on Earth over the last 2 million years. Tephra from this eruption has been spread over vast areas in Asia, where it constitutes a major time marker close to the Marine Isotope Stage 4/5 boundary. As yet, no tephra associated with Toba has been identified in Greenland or Antarctic ice cores. Based on new accurate dating of Toba tephra and on accurately dated European stalagmites, the Toba event is known to occur between the onsets of Greenland interstadials (GI 19 and 20. Furthermore, the existing linking of Greenland and Antarctic ice cores by gas records and by the bipolar seesaw hypothesis suggests that the Antarctic counterpart is situated between Antarctic Isotope Maxima (AIM 19 and 20. In this work we suggest a direct synchronization of Greenland (NGRIP and Antarctic (EDML ice cores at the Toba eruption based on matching of a pattern of bipolar volcanic spikes. Annual layer counting between volcanic spikes in both cores allows for a unique match. We first demonstrate this bipolar matching technique at the already synchronized Laschamp geomagnetic excursion (41 ka BP before we apply it to the suggested Toba interval. The Toba synchronization pattern covers some 2000 yr in GI-20 and AIM-19/20 and includes nine acidity peaks that are recognized in both ice cores. The suggested bipolar Toba synchronization has decadal precision. It thus allows a determination of the exact phasing of inter-hemispheric climate in a time interval of poorly constrained ice core records, and it allows for a discussion of the climatic impact of the Toba eruption in a global perspective. The bipolar linking gives no support for a long-term global cooling caused by the Toba eruption as Antarctica experiences a major warming shortly after the event. Furthermore, our bipolar match provides a way to place palaeo-environmental records other than ice cores into a

  5. Direct linking of Greenland and Antarctic ice cores at the Toba eruption (74 ka BP)

    Svensson, A.; Bigler, M.; Fischer, H.; Johnsen, S. J.; Kipfstuhl, S.; Parrenin, F.; Rasmussen, S. O.; Steffensen, J. P.; Vinther, B. M.; Wegner, A.

    2012-04-01

    The Toba eruption that occurred some 74 ka ago in Sumatra, Indonesia, is among the largest volcanic events on Earth over the last 2 million years. Tephra from this eruption has been spread over vast areas in Asia where it constitutes a major reference horizon close to the Marine Isotope Stage 3/4 (MIS 3/4) boundary. Up to now, no tephra has been associated with Toba neither in Greenland nor in Antarctic ice cores, but based on Toba tephra identified in marine records from the Arabian Sea it is very likely that Greenland ice core acidity spikes related to Toba occur towards the end of Greenland Interstadial 20 (GI-20). Furthermore, the linking of Greenland and Antarctic ice cores by gas records suggests that the Antarctica counterpart should be situated between Antarctic Isotope Maxima (AIM) 19 and 20. In this work we suggest a direct synchronization of Greenland (NGRIP) and Antarctic (EDML) ice cores based on matching of a pattern of bi-polar volcanic spikes and annual layer counting in both cores around 74 ka BP. The synchronization pattern covers some 2000 years in GI-20 and AIM 19/20 and includes 5 major and several minor acidity peaks that are recognized in both ice cores. The most prominent acidity spikes in this time interval that occur towards the end of GI-20, are those thought to originate from Toba, but the proposed linking is independent of the source of the volcanic spikes. Although the linking of Greenland and Antarctic ice cores around Toba is already quite well constrained by matching of gas records, the relative phasing between ice cores from the two hemispheres still has some uncertainty related to the offset in the age of ice and air bubbles in the ice cores (delta-gas age). The identification of a direct Toba synchronization may help to determine the exact phasing of inter-hemispheric climate during this period and to constrain delta-gas ages. It also provides a way to place paleo-environmental records other than ice cores into a precise climatic

  6. Unequivocal detection of ozone recovery in the Antarctic Ozone Hole through significant increases in atmospheric layers with minimum ozone

    de Laat, Jos; van Weele, Michiel; van der A, Ronald

    2015-04-01

    An important new landmark in present day ozone research is presented through MLS satellite observations of significant ozone increases during the ozone hole season that are attributed unequivocally to declining ozone depleting substances. For many decades the Antarctic ozone hole has been the prime example of both the detrimental effects of human activities on our environment as well as how to construct effective and successful environmental policies. Nowadays atmospheric concentrations of ozone depleting substances are on the decline and first signs of recovery of stratospheric ozone and ozone in the Antarctic ozone hole have been observed. The claimed detection of significant recovery, however, is still subject of debate. In this talk we will discuss first current uncertainties in the assessment of ozone recovery in the Antarctic ozone hole by using multi-variate regression methods, and, secondly present an alternative approach to identify ozone hole recovery unequivocally. Even though multi-variate regression methods help to reduce uncertainties in estimates of ozone recovery, great care has to be taken in their application due to the existence of uncertainties and degrees of freedom in the choice of independent variables. We show that taking all uncertainties into account in the regressions the formal recovery of ozone in the Antarctic ozone hole cannot be established yet, though is likely before the end of the decade (before 2020). Rather than focusing on time and area averages of total ozone columns or ozone profiles, we argue that the time evolution of the probability distribution of vertically resolved ozone in the Antarctic ozone hole contains a better fingerprint for the detection of ozone recovery in the Antarctic ozone hole. The advantages of this method over more tradition methods of trend analyses based on spatio-temporal average ozone are discussed. The 10-year record of MLS satellite measurements of ozone in the Antarctic ozone hole shows a

  7. The pressure-temperature-time evolution of the Antarctic Peninsula - magmatic arc and/or terrane tectonics?

    Wendt, A. S.; Vidal, O.; Vaughan, A.

    2003-04-01

    rocks in order to test whether the terranes forming the Antarctic Peninsula are locally or exotically derived. We are examining two possibilities: (1) a local-derivation, where a para-autochthonous subduction-related magmatic arc collides with the adjacent continental margin, and (2) an exotic-derivation, where the Antarctic Peninsula is composed of far-traveled micro-continental and oceanic terranes which may have originated as far away as New Zealand and Australia.

  8. Bacterial diversity of autotrophic enriched cultures from remote, glacial Antarctic, Alpine and Andean aerosol, snow and soil samples

    E. González-Toril

    2009-01-01

    Full Text Available Four different communities and one culture of autotrophic microbial assemblages were obtained by incubation of samples collected from high elevation snow in the Alps (Mt. Blanc area and the Andes (Nevado Illimani summit, Bolivia, from Antarctic aerosol (French station Dumont d'Urville and a maritime Antarctic soil (King George Island, South Shetlands, Uruguay Station Artigas, in a minimal mineral (oligotrophic media. Molecular analysis of more than 200 16S rRNA gene sequences showed that all cultured cells belong to the Bacteria domain. Phylogenetic comparison with the currently available rDNA database allowed sequences belonging to Proteobacteria Alpha-, Beta- and Gamma-proteobacteria, Actinobacteria and Bacteroidetes phyla to be identified. The Andes snow culture was the richest in bacterial diversity (eight microorganisms identified and the marine Antarctic soil the poorest (only one. Snow samples from Col du Midi (Alps and the Andes shared the highest number of identified microorganisms (Agrobacterium, Limnobacter, Aquiflexus and two uncultured Alphaproteobacteria clones. These two sampling sites also shared four sequences with the Antarctic aerosol sample (Limnobacter, Pseudonocardia and an uncultured Alphaproteobacteriaclone. The only microorganism identified in the Antarctica soil (Brevundimonas sp. was also detected in the Antarctic aerosol. Most of the identified microorganisms had been detected previously in cold environments, marine sediments soils and rocks. Air current dispersal is the best model to explain the presence of very specific microorganisms, like those identified in this work, in environments very distant and very different from each other.

  9. Multi-year record of atmospheric mercury at Dumont d'Urville, East Antarctic coast: continental outflow and oceanic influences

    Angot, Hélène; Dion, Iris; Vogel, Nicolas; Legrand, Michel; Magand, Olivier; Dommergue, Aurélien

    2016-07-01

    Under the framework of the Global Mercury Observation System (GMOS) project, a 3.5-year record of atmospheric gaseous elemental mercury (Hg(0)) has been gathered at Dumont d'Urville (DDU, 66°40' S, 140°01' E, 43 m above sea level) on the East Antarctic coast. Additionally, surface snow samples were collected in February 2009 during a traverse between Concordia Station located on the East Antarctic plateau and DDU. The record of atmospheric Hg(0) at DDU reveals particularities that are not seen at other coastal sites: a gradual decrease of concentrations over the course of winter, and a daily maximum concentration around midday in summer. Additionally, total mercury concentrations in surface snow samples were particularly elevated near DDU (up to 194.4 ng L-1) as compared to measurements at other coastal Antarctic sites. These differences can be explained by the more frequent arrival of inland air masses at DDU than at other coastal sites. This confirms the influence of processes observed on the Antarctic plateau on the cycle of atmospheric mercury at a continental scale, especially in areas subject to recurrent katabatic winds. DDU is also influenced by oceanic air masses and our data suggest that the ocean plays a dual role on Hg(0) concentrations. The open ocean may represent a source of atmospheric Hg(0) in summer whereas the sea-ice surface may provide reactive halogens in spring that can oxidize Hg(0). This paper also discusses implications for coastal Antarctic ecosystems and for the cycle of atmospheric mercury in high southern latitudes.

  10. 我国南极陨石收集进展(2000-2010)%Progress of Antarctic Meteorite Collection in China(2000-2010)

    缪秉魁; 林杨挺; 王道德; 欧阳自远

    2012-01-01

    Antarctic meteorite survey has been one of the most important Antarctic expedition projects of many countries since the middle of the last century. China Antarctic Research Expedition (CHINARE) began to search meteorites in Antarctica at the end of the last century, and has obtained great achievements in the new century. During the first decade of this century, CHIN ARE has collected more than ten thousands Antarctic meteorite.s, China became one of the richest countries with Antarctic meteorites, and had found a new meteorite concentrated area in East Antarctica-Grove Mountains.%自上世纪中叶以来,南极陨石收集就成为国际上南极考察项目中的一个重要亮点.在世纪之交之际,我国南极考察队开始了南极陨石收集,在短短的十年时间,在南极陨石收集方面取得了丰硕成果.我国不但收集了一万多块陨石样品,成为拥有南极陨石最多的国家之一,而且新发现了一个陨石富集区——格罗夫山.

  11. Study on Optimization of Phase Offset at Adjacent Intersections

    Yuanli GU

    2010-11-01

    Full Text Available Optimization of the phase offset at adjacent intersections is the key parameter regarding coordinated control of traffic signal for adjacent intersections, which decides the effect of the coordinated control for adjacent intersections. According to characters of saturated traffic flow of Chinese urban road, this thesis establishes a model for optimization of phase offset for adjacent interactions and finds a solution from such model by adopting genetic algorithm. The model is verified by actual traffic flow datum of two adjacent signal intersections on Changan Avenue. Then a comparison is made between the optimization result of such model and that of the existing mathematical method and SYNCHRO model, which indicates that the model established by this thesis can reduce the delay suffered by vehicles at the intersections and increase the traffic efficiency of the intersections.

  12. Aerial photography of Russian Antarctic stations Mirny and Progress in summer of 2014/15

    S. S. Pryakhin

    2015-01-01

    Full Text Available Aerial photographing performed during the field season of 60th Russian Antarctic Expedition (2014/2015 made possible to construct a photoplan of the Mirny station. Its size is 3,5×3,5 km with resolution of 16 pixels/cm, and it will be used as a basis for designing of new airport. Similar work had been done over the Progress station along the route “Progress – Vostok”, about 35 km long. It was found that any crevasses dangerous for people and transport were absent on this area.

  13. Draft Genome Sequences of the Antimicrobial Producers Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 Isolated from Antarctic Sediments

    Presta, Luana; Inzucchi, Ilaria; Bosi, Emanuele; Fondi, Marco; Perrin, Elena; Maida, Isabel; Miceli, Elisangela; Tutino, Maria Luisa; Lo Giudice, Angelina; de Pascale, Donatella

    2016-01-01

    We report here the draft genome sequence of the Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 strains, isolated from Antarctic sediments during a summer campaign near coastal areas of Terra Nova Bay (Antarctica). Genome sequence knowledge allowed the identification of genes associated with the production of bioactive compounds and antibiotic resistance. Furthermore, it will be instrumental for comparative genomics and the fulfillment of both basic and application-oriented investigations. PMID:27469957

  14. 'Unlocking the archive': Using photogrammetry of historic aerial photographs to extend the record of glacier change on the Antarctic Peninsula

    Clarke, Lucy; Fox, Adrian

    2014-05-01

    Changes to glacier fronts and ice shelves and glacier acceleration are well documented, but there is almost no data on mass changes for the more than 400 glaciers on the Antarctic Peninsula. Current research demonstrates that the Antarctic Peninsula is contributing to sea-level change at a similar rate to that of other fast-changing near-polar or large mountain-glacier environments such as Iceland, Patagonia and Alaska (Hock, 2009). Forecasting the future impacts of the Antarctic Peninsula ice sheet on sea level will require a much improved understanding of 20th Century and contemporary glacier mass changes. Satellite data has been used to calculate these changes over the last three decades, but methods to quantify this over a longer time scale have eluded researchers. However, there is an archive of aerial photography of the Antarctic Peninsula dating back to the 1940s, this has been largely ignored due to the range of technical problems associated with deriving quantitative data from historic aerial photographs. This presentation demonstrates how advances in photogrammetric processing and capture of modern aerial photography have allowed this archive to be 'unlocked'. Accurate photogrammetric reconstruction from aerial photographs traditionally requires known ground control points acquired in the field; in remote and inaccessible areas, such as the Antarctic Peninsula, this is often impossible and so has restricted the use of photogrammetric analysis of the available aerial photography. A method for providing control for historic photos without fieldwork on the ground, by linking them to a newly acquired, highly accurate photogrammetric model adjusted through direct kinematic GPS positioning of the camera was developed by Fox and Cziferszky (2008), and this is now being applied to a number of glaciers across the Antarctic Peninsular using Intergraph Photogrammetry Suite (Erdas LPS 2013) software. This presentation will outline the photogrammetric workflow and

  15. Interhemispheric coupling, the West Antarctic Ice Sheet and warm Antarctic interglacials

    P. B. Holden

    2010-07-01

    Full Text Available Ice core evidence indicates that even though atmospheric CO2 concentrations did not exceed ~300 ppm at any point during the last 800 000 years, East Antarctica was at least ~3–4 °C warmer than preindustrial (CO2~280 ppm in each of the last four interglacials. During the previous three interglacials, this anomalous warming was short lived (~3000 years and apparently occurred before the completion of Northern Hemisphere deglaciation. Hereafter, we refer to these periods as "Warmer than Present Transients" (WPTs. We present a series of experiments to investigate the impact of deglacial meltwater on the Atlantic Meridional Overturning Circulation (AMOC and Antarctic temperature. It is well known that a slowed AMOC would increase southern sea surface temperature (SST through the bipolar seesaw and observational data suggests that the AMOC remained weak throughout the terminations preceding WPTs, strengthening rapidly at a time which coincides closely with peak Antarctic temperature. We present two 800 kyr transient simulations using the Intermediate Complexity model GENIE-1 which demonstrate that meltwater forcing generates transient southern warming that is consistent with the timing of WPTs, but is not sufficient (in this single parameterisation to reproduce the magnitude of observed warmth. In order to investigate model and boundary condition uncertainty, we present three ensembles of transient GENIE-1 simulations across Termination II (135 000 to 124 000 BP and three snapshot HadCM3 simulations at 130 000 BP. Only with consideration of the possible feedback of West Antarctic Ice Sheet (WAIS retreat does it become possible to simulate the magnitude of observed warming.

  16. Zooplankton biomass estimated from digitalized images in Antarctic waters: A calibration exercise

    HernáNdez-León, Santiago; Montero, Irene

    2006-05-01

    The direct measurement of zooplankton biomass following the different analytical procedures normally requires the destruction of the samples. The use of conversion factors to estimate biomass from nondestructive methods is still a challenge. The widespread use of image analyzers and optical counters in biological oceanography provides a useful tool to measure the abundance and size spectrum of zooplanktonic organisms in real or quasi-real time. Both methodologies measure the equivalent spherical diameter and/or the body area of organisms. In order to estimate biomass from the highly valuable information generated by the size spectrum of the sample, we measured the relationship between individual body area and individual biomass of the most common species and groups of zooplankton in Antarctic waters. The slope of the regression for each different species and groups of taxa was not significantly different from that obtained by pooling all taxa, thus providing a general relationship for the entire size spectrum of zooplankton. The biomass estimated from the body area spectrum of samples obtained around the Antarctic Peninsula agreed with other measurements of biomass in the region. The proposed conversion factor could provide for rapid estimates of biomass of net-collected zooplankton from imaging devices or optical plankton counters.

  17. Levoglucosan indicates high levels of biomass burning aerosols over oceans from the Arctic to Antarctic

    Hu, Q.; Xie, Z.; Wang, X.; Kang, H.; Zhang, P.

    2015-12-01

    Biomass burning discharges numerous kinds of gases and aerosols, such as carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), black carbon (BC), alcohols, organic acids and persistent organic pollutants (POPs), and is known to affect air quality, global carbon cycle, and climate. However, the extent to which biomass burning gases/aerosols are present on a global scale, especially in the marine atmosphere, is poorly understood. Here we measure levoglucosan, a superior molecular tracer of biomass burning aerosols because of its single source, in marine air from the Arctic Ocean through the North and South Pacific Ocean to coastal Antarctica during burning season. Levoglucosan was found to be present in all regions at ng/m3 levels. As a whole, levoglucosan concentrations in the Southern Hemisphere were comparable to those in the Northern Hemisphere. Marine air in the mid-latitudes (30°-60° N and S) has the highest levoglucosan loading due to the emission from adjacent lands. Air over the Arctic Ocean which affected by biomass burning in the east Siberia has intermediate loading. Equatorial latitudes is the main source of biomass burning emissions, however, levoglucosan is in relatively low level. Large amount of precipitation and high hydroxyl radical concentration in this region cause more deposition and degradation of levoglucosan during transport. Previous studies were debatable on the influence of biomass burning on the Antarctic because of uncertain source of BC. Here via levoglucosan, it is proved that although far away from emission sources, the Antarctic is still affected by biomass burning aerosols which may be derived from South America. Biomass burning has a significant impact on mercury (Hg) and water-soluble organic carbon (WSOC) in marine aerosols from pole to pole, with more contribution to WSOC in the Northern Hemisphere than in the Southern Hemisphere.

  18. Impact of model resolution for on-shelf heat transport along the West Antarctic Peninsula

    Graham, Jennifer A.; Dinniman, Michael S.; Klinck, John M.

    2016-10-01

    The flux of warm deep water onto Antarctic continental shelves plays a vital role in determining water mass properties adjacent to the continent. A regional model, with two different grid resolutions, has been used to simulate ocean processes along the West Antarctic Peninsula. At both 4 km and 1.5 km resolution, the model reproduces the locations of warm intrusions, as shown through comparison with observations from instrumented seals. However, the 1.5 km simulation shows greater on-shelf heat transport, leading to improved representation of heat content on the shelf. This increased heat transport is associated with increased eddy activity, both at the shelf-break and in the deep ocean off-shore. Cross-shelf troughs are key locations of on-shelf heat transport. Comparison of two troughs, Belgica and Marguerite, shows differing responses to increased resolution. At higher resolution, there is an increased on-shelf volume transport at Belgica Trough, but not at Marguerite Trough. This is likely related to the differing structure of the shelf-break jet between these two locations. The increased heat flux at Marguerite Trough is attributed to increased heat content in the on-shelf transport. Increased eddy activity off-shelf may lead to greater cross-front heat transport, and therefore increased heat available above the continental slope. While these simulations differ in their magnitude of heat transport, both show similar patterns of variability. Variations in wind stress lead to variations in speed of the shelf-break jet, and therefore on-shelf heat transport. These results demonstrate the importance of model resolution for understanding cross-shelf transport around Antarctica.

  19. Antarctic Single Frames = Frame Level Records of Antarctica Photos: 1946 - 2000

    U.S. Geological Survey, Department of the Interior — Aerial photographs of Antarctica from the United States Antarctic Resource Center (USARC) and the British Antarctic Survey (BAS) are maintained in this collection....

  20. Antarctic sea ice variability and trends, 1979–2010

    D. J. Cavalieri

    2012-08-01

    Full Text Available In sharp contrast to the decreasing sea ice coverage of the Arctic, in the Antarctic the sea ice cover has, on average, expanded since the late 1970s. More specifically, satellite passive-microwave data for the period November 1978–December 2010 reveal an overall positive trend in ice extents of 17 100 ± 2300 km2 yr−1. Much of the increase, at 13 700 ± 1500 km2 yr−1, has occurred in the region of the Ross Sea, with lesser contributions from the Weddell Sea and Indian Ocean. One region, that of the Bellingshausen/Amundsen Seas, has (like the Arctic instead experienced significant sea ice decreases, with an overall ice extent trend of −8200 ± 1200 km2 yr−1. When examined through the annual cycle over the 32-yr period 1979–2010, the Southern Hemisphere sea ice cover as a whole experienced positive ice extent trends in every month, ranging in magnitude from a low of 9100 ± 6300 km2 yr−1 in February to a high of 24 700 ± 10 000 km2 yr−1 in May. The Ross Sea and Indian Ocean also had positive trends in each month, while the Bellingshausen/Amundsen Seas had negative trends in each month, and the Weddell Sea and western Pacific Ocean had a mixture of positive and negative trends. Comparing ice-area results to ice-extent results, in each case the ice-area trend has the same sign as the ice-extent trend, but the magnitudes of the two trends differ, and in some cases these differences allow inferences about the corresponding changes in sea ice concentrations. The strong pattern of decreasing ice coverage in the Bellingshausen/Amundsen Seas region and increasing ice coverage in the Ross Sea region is suggestive of changes in atmospheric circulation. This is a key topic for future research.

  1. Antarctic Sea Ice Variability and Trends, 1979-2010

    Parkinson, C. L.; Cavalieri, D. J.

    2012-01-01

    In sharp contrast to the decreasing sea ice coverage of the Arctic, in the Antarctic the sea ice cover has, on average, expanded since the late 1970s. More specifically, satellite passive-microwave data for the period November 1978 - December 2010 reveal an overall positive trend in ice extents of 17,100 +/- 2,300 square km/yr. Much of the increase, at 13,700 +/- 1,500 square km/yr, has occurred in the region of the Ross Sea, with lesser contributions from the Weddell Sea and Indian Ocean. One region, that of the Bellingshausen/Amundsen Seas, has, like the Arctic, instead experienced significant sea ice decreases, with an overall ice extent trend of -8,200 +/- 1,200 square km/yr. When examined through the annual cycle over the 32-year period 1979-2010, the Southern Hemisphere sea ice cover as a whole experienced positive ice extent trends in every month, ranging in magnitude from a low of 9,100 +/- 6,300 square km/yr in February to a high of 24,700 +/- 10,000 square km/yr in May. The Ross Sea and Indian Ocean also had positive trends in each month, while the Bellingshausen/Amundsen Seas had negative trends in each month, and the Weddell Sea and Western Pacific Ocean had a mixture of positive and negative trends. Comparing ice-area results to ice-extent results, in each case the ice-area trend has the same sign as the ice-extent trend, but differences in the magnitudes of the two trends identify regions with overall increasing ice concentrations and others with overall decreasing ice concentrations. The strong pattern of decreasing ice coverage in the Bellingshausen/Amundsen Seas region and increasing ice coverage in the Ross Sea region is suggestive of changes in atmospheric circulation. This is a key topic for future research.

  2. Antarctic sea ice variability and trends, 1979–2010

    D. J. Cavalieri

    2012-03-01

    Full Text Available In sharp contrast to the decreasing sea ice coverage of the Arctic, in the Antarctic the sea ice cover has, on average, expanded since the late 1970s. More specifically, satellite passive-microwave data for the period November 1978–December 2010 reveal an overall positive trend in ice extents of 17 100 ± 2300 km2 yr−1. Much of the increase, at 13 700 ± 1500 km2 yr−1, has occurred in the region of the Ross Sea, with lesser contributions from the Weddell Sea and Indian Ocean. One region, that of the Bellingshausen/Amundsen Seas, has, like the Arctic, instead experienced significant sea ice decreases, with an overall ice extent trend of −8200 ± 1200 km2 yr−1. When examined through the annual cycle over the 32-yr period 1979–2010, the Southern Hemisphere sea ice cover as a whole experienced positive ice extent trends in every month, ranging in magnitude from a low of 9100 ± 6300 km2 yr−1 in February to a high of 24 700 ± 10 000 km2 yr−1 in May. The Ross Sea and Indian Ocean also had positive trends in each month, while the Bellingshausen/Amundsen Seas had negative trends in each month, and the Weddell Sea and Western Pacific Ocean had a mixture of positive and negative trends. Comparing ice-area results to ice-extent results, in each case the ice-area trend has the same sign as the ice-extent trend, but differences in the magnitudes of the two trends identify regions with overall increasing ice concentrations and others with overall decreasing ice concentrations. The strong pattern of decreasing ice coverage in the Bellingshausen/Amundsen Seas region and increasing ice coverage in the Ross Sea region is suggestive of changes in atmospheric circulation. This is a key topic for future research.

  3. 77 FR 19537 - MARPOL Annex V Special Areas: Wider Caribbean Region

    2012-04-02

    ... Protocol on Environmental Protection to the Antarctic Treaty as It Pertains to Pollution From Ships Sec... defined and recognized for treaty purposes. However, the special area regulations do not apply in...

  4. Complex Geodetic Research in Ukrainian Antarctic Station "Academician Vernadsky" (Years 2002 - 2005, 2013-2014)

    Tretyak, Kornyliy; Hlotov, Volodymyr; Holubinka, Yuriy; Marusazh, Khrystyna

    2016-06-01

    In this paper is given an information about complex geodetic research in Ukrainian Antarctic station "Academician Vernadsky". Research were carried by Lviv polytechnic scientists, during Antarctic expeditions in years 2002 - 2005, 2013, 2014. Main objectives of the studies were: (a) study of the islands glaciers surface volumes changes in Antarctic archipelago and Antarctic Peninsula using terestrial laser scaning and digital terrestrial stereophotogrammetry survey; (b) investigation of Penola strain tectonic fault, using the results of precise GNSS observations.

  5. Skip spawning as a reproductive strategy in Antarctic fish species: the Antarctic silverfish (Pleuragramma antarctica case study

    Eva Pisano

    2015-11-01

    Full Text Available The Antarctic silverfish Pleuragramma antarctica (Notothenioidei, Nototheniidae is the most abundant pelagic fish inhabiting the frigid Antarctic coastal waters. It plays relevant roles in the local ecosystems, where it is often considered a keystone species connecting lower and upper trophic levels within the coastal marine food web. Despite its ecological relevance, and although many aspects of the Antarctic silverfish biology have already been elucidated, knowledge on important components of its life cycle, including the reproductive features, is still poor. The available data on the reproduction of the Antarctic silverfish remains fragmentary and, in particular, information on the silverfish from the Ross Sea is lacking, in spite of the intensive ecological studies on this unique region and the fact that the only known nursery ground for this species is located in Terra Nova Bay (Ross Sea where hatching occurs under the sea-ice. We present the here first description of the reproductive features of Antarctic silverfish from fish sampled in late Summer (mid February 2008 in the Ross Sea. The gross reproductive traits are consistent with those reported from other Antarctic sectors but, interestingly, widespread follicular atresia has been detected in the fish examined. The intensity and prevalence of such a follicular degenerative process suggest that skip spawning (not all adults spawn every year could be a reproductive strategy of this Antarctic species. Such an hypothesis is discussed both on the short-term and on the evolutionary time-scale. Overall, the data presented also contribute to support the acknowledgment that skip-spawning is a diffuse phenomenon in fishes.

  6. Antarctic Yeasts: Biodiversity and Potential Applications

    Shivaji, S.; Prasad, G. S.

    This review is an attempt in cataloguing the diversity of yeasts in Antarctica, highlight their biotechnological potential and understand the basis of adaptation to low temperature. As of now several psychrophilic and psychrotolerant yeasts from Antarctic soils and marine waters have been characterized with respect to their growth characteristics, ecological distribution and taxonomic significance. Interestingly most of these species belonged to basidiomycetous yeasts which as a group are known for their ability to circumvent and survive under stress conditions. Simultaneously their possible role as work horses in the biotechnological industry was recognized due to their ability to produce novel enzymes and biomolecules such as agents for the breakdown of xenobiotics, and novel pharmaceutical chemi cals. The high activity of psychrophilic enzymes at low and moderate temperatures offers potential economic benefits. As of now lipases from Pseudozyma antarctica have been extensively studied to understand their unique thermal stability at 90°C and also because of its use in the pharmaceutical, agriculture, food, cosmetics and chemical industry. A few of the other enzymes which have been studied include extracellular alpha-amylase and glucoamylase from the yeast Pseudozyma antarctica (Candida antarctica), an extra-cellular protease from Cryptococcus humicola, an aspartyl proteinase from Cryptococcus humicola, a novel extracellular subtilase from Leucosporidium antarcticum, and a xylanase from Cryptococcus adeliensis

  7. Biogeography of circum-Antarctic springtails.

    McGaughran, Angela; Stevens, Mark I; Holland, Barbara R

    2010-10-01

    We examine the effects of isolation over both ancient and contemporary timescales on evolutionary diversification and speciation patterns of springtail species in circum-Antarctica, with special focus on members of the genus Cryptopygus (Collembola, Isotomidae). We employ phylogenetic analysis of mitochondrial DNA (cox1), and ribosomal DNA (18S and 28S) genes in the programmes MrBayes and RAxML. Our aims are twofold: (1) we evaluate existing taxonomy in light of previous work which found dubious taxonomic classification in several taxa based on cox1 analysis; (2) we evaluate the biogeographic origin of our chosen suite of springtail species based on dispersal/vicariance scenarios, the magnitude of genetic divergence among lineages and the age and accessibility of potential habitat. The dubious taxonomic characterisation of Cryptopygus species highlighted previously is confirmed by our multi-gene phylogenetic analyses. Specifically, according to the current taxonomy, Cryptopygus antarcticus subspecies are not completely monophyletic and neither are Cryptopygus species in general. We show that distribution patterns among species/lineages are both dispersal- and vicariance-driven. Episodes of colonisation appear to have occurred frequently, the routes of which may have followed currents in the Southern Ocean. In several cases, the estimated divergence dates among species correspond well with the timing of terrestrial habitat availability. We conclude that these isotomid springtails have a varied and diverse evolutionary history in the circum-Antarctic that consists of both ancient and recent elements and is reflected in a dynamic contemporary fauna.

  8. Quantification of ikaite in Antarctic sea ice

    M. Fischer

    2012-02-01

    Full Text Available Calcium carbonate precipitation in sea ice can increase pCO2 during precipitation in winter and decrease pCO2 during dissolution in spring. CaCO3 precipitation in sea ice is thought to potentially drive significant CO2 uptake by the ocean. However, little is known about the quantitative spatial and temporal distribution of CaCO3 within sea ice. This is the first quantitative study of hydrous calcium carbonate, as ikaite, in sea ice and discusses its potential significance for the carbon cycle in polar oceans. Ice cores and brine samples were collected from pack and land fast sea ice between September and December 2007 during an expedition in the East Antarctic and another off Terre Adélie, Antarctica. Samples were analysed for CaCO3, Salinity, DOC, DON, Phosphate, and total alkalinity. A relationship between the measured parameters and CaCO3 precipitation could not be observed. We found calcium carbonate, as ikaite, mostly in the top layer of sea ice with values up to 126 mg ikaite per liter melted sea ice. This potentially represents a contribution between 0.12 and 9 Tg C to the annual carbon flux in polar oceans. The horizontal distribution of ikaite in sea ice was heterogenous. We also found the precipitate in the snow on top of the sea ice.

  9. Ionospheric irregularities at Antarctic using GPS measurements

    Sunita Tiwari; Amit Jain; Shivalika Sarkar; Sudhir Jain; A K Gwal

    2012-04-01

    The purpose of this work is to study the behaviour of the ionospheric scintillation at high latitude during geomagnetically quiet and disturbed conditions which is one of the most relevant themes in the space weather studies. Scintillation is a major problem in navigation application using GPS and in satellite communication at high latitudes. Severe amplitude fading and strong scintillation affect the reliability of GPS navigational system and satellite communication. To study the effects of the ionospheric scintillations, GPS receiver installed at Antarctic station Maitri (Geog. 70.76°S; 11.74°E) was used. The data is collected by using GISTM 4004A, NOVATEL’S GPS receiver during March 2008. Studies show that percentage occurrence of phase scintillation is well correlated with geomagnetic activity during the observation period. The result also shows that very intense scintillations can degrade GPS based location determination due to loss of lock of satellites. These findings indicate that the dependence of scintillations and irregularity occurrence on geomagnetic activity is associated with the magnetic local time (MLT). Large number of patches are reported and their activity depends on the magnetic activity index.

  10. Evidence for warmer interglacials in East Antarctic ice cores.

    Sime, L C; Wolff, E W; Oliver, K I C; Tindall, J C

    2009-11-19

    Stable isotope ratios of oxygen and hydrogen in the Antarctic ice core record have revolutionized our understanding of Pleistocene climate variations and have allowed reconstructions of Antarctic temperature over the past 800,000 years (800 kyr; refs 1, 2). The relationship between the D/H ratio of mean annual precipitation and mean annual surface air temperature is said to be uniform +/-10% over East Antarctica and constant with time +/-20% (refs 3-5). In the absence of strong independent temperature proxy evidence allowing us to calibrate individual ice cores, prior general circulation model (GCM) studies have supported the assumption of constant uniform conversion for climates cooler than that of the present day. Here we analyse the three available 340 kyr East Antarctic ice core records alongside input from GCM modelling. We show that for warmer interglacial periods the relationship between temperature and the isotopic signature varies among ice core sites, and that therefore the conversions must be nonlinear for at least some sites. Model results indicate that the isotopic composition of East Antarctic ice is less sensitive to temperature changes during warmer climates. We conclude that previous temperature estimates from interglacial climates are likely to be too low. The available evidence is consistent with a peak Antarctic interglacial temperature that was at least 6 K higher than that of the present day -approximately double the widely quoted 3 +/- 1.5 K (refs 5, 6).

  11. Brain and sense organ anatomy and histology of two species of phyletically basal non-Antarctic thornfishes of the Antarctic suborder Notothenioidei (Perciformes: Bovichtidae).

    Eastman, Joseph T; Lannoo, Michael J

    2007-06-01

    The predominantly non-Antarctic family Bovichtidae is phyletically basal within the perciform suborder Notothenioidei, the dominant component of the Antarctic fish fauna. In this article we focus on the South Atlantic bovichtids Bovichtus diacanthus, the klipfish from tide pools at Tristan da Cunha, and Cottoperca gobio, the frogmouth from the Patagonian shelf and Falkland Islands. We document the anatomy and histology of the brains, olfactory apparatus, retina, and cephalic lateral line system. We also use the microvascular casting agent Microfil to examine ocular vascular structures. We provide detailed drawings of the brains and cranial nerves of both species. Typical of perciforms, the brains of both species have a well-developed tectum and telencephalon and robust thalamic nuclei. The telencephalon of C. gobio is prominently lobed, with the dorsomedial nucleus more conspicuous than in any other notothenioid. The corpus cerebelli is relatively small and upright and, unlike other notothenioids, has prominent transverse sulci on the dorsal and caudal surfaces. Areas for lateral line mechanoreception (eminentia granularis and crista cerebellaris) are also conspicuous but olfactory, gustatory, and somatosensory areas are less prominent. The anterior lateral line nerve complex is larger than the posterior lateral line nerve in B. diacanthus, and in their cephalic lateral line systems both species possess branched membranous tubules (which do not contain neuromasts) with small pores. These are especially complex in B. diacanthus where they become increasingly branched and more highly pored in progressively larger specimens. Superficial neuromasts are sparse. Both species have duplex (cone and rod) retinae that are 1.25-fold thicker and have nearly 5-fold more photoreceptors and than those of most Antarctic notothenioids. Convergence ratios are also high for bovichtids. Bovichtus diacanthus has a yellow intraocular filter in the dorsal aspect of the cornea. Both

  12. Remodeling in myocardium adjacent to an infarction in the pig left ventricle.

    Zimmerman, Scott D; Criscione, John; Covell, James W

    2004-12-01

    Changes in the structure of the "normal" ventricular wall adjacent to an infarcted area involve all components of the myocardium (myocytes, fibroblasts and the extracellular matrix, and the coronary vasculature) and their three-dimensional structural relationship. Assessing changes in these components requires tracking material markers in the remodeling tissue over long periods of time with a three-dimensional approach as well as a detailed histological evaluation of the remodeled structure. The purpose of the present study was to examine the hypotheses that changes in the tissue adjacent to an infarct are related to myocyte elongation, myofiber rearrangement, and changes in the laminar architecture of the adjacent tissue. Three weeks after myocardial infarction, noninfarcted tissue adjacent to the infarct remodeled by expansion along the direction of the fibers and in the cross fiber direction. These changes are consistent with myocyte elongation and myofiber rearrangement (slippage), as well as a change in cell shape to a more elliptical cross section with the major axis in the epicardial tangent plane, and indicate that reorientation of fibers either via "cell slippage" or changes in orientation of the laminar structure of the ventricular wall are quantitatively important aspects of the remodeling of the normally perfused myocardium.

  13. Divergent trajectories of Antarctic surface melt under two 21st century climate scenarios

    Trusel, L.D.; Frey, Karen; Das, Sarah; Karnauskas, Kristopher; Kuipers Munneke, P.; van Meijgaard, E.; van den Broeke, M.R.

    2015-01-01

    Ice shelves modulate Antarctic contributions to sea-level rise and thereby represent a critical, climate-sensitive interface between the Antarctic ice sheet and the global ocean. Following rapid atmospheric warming over the past decades, Antarctic Peninsula ice shelves have progressively retreated,

  14. Isolation and characterization of Campylobacter spp. from Antarctic fur seals (Arctocephalus gazella) at Deception Island, Antarctica.

    García-Peña, F J; Pérez-Boto, D; Jiménez, C; San Miguel, E; Echeita, A; Rengifo-Herrera, C; García-Párraga, D; Ortega-Mora, L M; Pedraza-Díaz, S

    2010-09-01

    The presence of Campylobacter spp. was investigated in 41 Antarctic fur seals (Arctocephalus gazella) and 9 Weddell seals (Leptonychotes weddellii) at Deception Island, Antarctica. Infections were encountered in six Antarctic fur seals. The isolates, the first reported from marine mammals in the Antarctic region, were identified as Campylobacter insulaenigrae and Campylobacter lari.

  15. 78 FR 41960 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    2013-07-12

    ... Environmental Protocol to the Antarctic Treaty. All other wastes would be packaged and removed to the yacht for... Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act...

  16. 77 FR 9707 - U.S. Antarctic Program Blue Ribbon Panel Review; Notice of Meeting

    2012-02-17

    ..., innovative, affordable, sustainable, and consistent with the Antarctic Treaty. Agenda: Present the Panel with... U.S. Antarctic Program Blue Ribbon Panel Review; Notice of Meeting In accordance with Federal... following meeting: Name: U.S. Antarctic Program Blue Ribbon Panel Review, 76826. Date/Time: March 5, 2012,...

  17. 78 FR 41959 - Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978

    2013-07-12

    ... Modification Requested: The Foundation must report to the Antarctic Treaty annually, no later than June 1 on... Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of permit modification under the Antarctic Conservation Act of...

  18. 76 FR 63329 - U.S. Antarctic Program Blue Ribbon Panel Review; Notice of Meeting

    2011-10-12

    ..., affordable, sustainable, and consistent with the Antarctic Treaty. Agenda: First meeting of the Panel to... Doc No: 2011-26281] NATIONAL SCIENCE FOUNDATION U.S. Antarctic Program Blue Ribbon Panel Review... National Science Foundation announces the following meeting: Name: U.S. Antarctic Program Blue Ribbon...

  19. 77 FR 1743 - U.S. Antarctic Program Blue Ribbon Panel; Notice of Meeting

    2012-01-11

    ... sound, safe, innovative, affordable, sustainable, and consistent with the Antarctic Treaty. Agenda... U.S. Antarctic Program Blue Ribbon Panel; Notice of Meeting In accordance with Federal Advisory...: Name: U.S. Antarctic Program Blue Ribbon Panel Review, 76826. Date/Time: January 24, 2012, 8 a.m. to...

  20. 78 FR 51213 - Notice of Permits Issued Under the Antarctic Conservation Act of 1978

    2013-08-20

    ... Protocol on Environmental Protection to the Antarctic Treaty done at Madrid on October 4, 1991. The NSF is... Notice of Permits Issued Under the Antarctic Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of document availability under the Antarctic Conservation of 1978, as amended by...

  1. 77 FR 20852 - U.S. Antarctic Program Blue Ribbon Panel Review; Notice of Meeting

    2012-04-06

    ... the Antarctic Treaty. Agenda: Present the Panel with additional programmatic information related to... U.S. Antarctic Program Blue Ribbon Panel Review; Notice of Meeting In accordance with Federal... following meeting: Name: U.S. Antarctic Program Blue Ribbon Panel Review, 76826. Date/Time: April 20,...

  2. 77 FR 38834 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    2012-06-29

    ... Science Foundation. ACTION: Notice of permit applications received under the Antarctic Conservation Act of.... SUPPLEMENTARY INFORMATION: The National Science Foundation, as directed by the Antarctic Conservation Act of 1978 (Pub. L. 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996,...

  3. 78 FR 28000 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    2013-05-13

    ... Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of... National Science Foundation, as directed by the Antarctic Conservation Act of 1978 (Pub. L. 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has developed regulations for...

  4. 77 FR 67407 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    2012-11-09

    ... Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of... National Science Foundation, as directed by the Antarctic Conservation Act of 1978 (Pub. L. 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has developed regulations for...

  5. 78 FR 59728 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    2013-09-27

    ... the Antarctic Conservation Act of 1978 (Pub. L. 95-541), as amended by the Antarctic Science, Tourism... From the Federal Register Online via the Government Publishing Office NATIONAL SCIENCE FOUNDATION Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 AGENCY:...

  6. fMRI Evidence of Acupoints Specificity in Two Adjacent Acupoints

    Hua Liu

    2013-01-01

    Full Text Available Objectives. Acupoint specificity is the foundation of acupuncture treatment. The aim of this study is to investigate whether the acupoint specificity exists in two adjacent acupoints. Design and Setting. Two adjacent real acupoints, LR3 (Taichong and ST44 (Neiting, and a nearby nonacupoint were selected. Thirty-three health volunteers were divided into three groups in random order, and each group only received acupuncture at one of the three points. While they received acupuncture, fMRI scan was performed. Results. The common cerebral activated areas responding to LR3 and ST44 included the contralateral primary somatosensory area (SI and ipsilateral cerebellum. Acupuncture at LR3 specifically activated contralateral middle occipital gyrus, ipsilateral medial frontal gyrus, superior parietal lobe, middle temporal gyrus, rostral anterior cingulate cortex (rACC, lentiform nucleus, insula, and contralateral thalamus. Stimulation at ST44 selectively activated ipsilateral secondary somatosensory area (SII, contralateral middle frontal gyrus, inferior frontal gyrus, lingual gyrus, lentiform nucleus, and bilateral posterior cingulate cortex (PCC. Conclusions. Acupuncture at adjacent acupoints elicits distinct cerebral activation patterns, and those specific patterns might be involved in the mechanism of the specific therapeutic effects of different acupoints.

  7. MAGIC-DML: Mapping/Measuring/Modeling Antarctic Geomorphology & Ice Change in Dronning Maud Land

    Rogozhina, Irina; Bernales, Jorge; Newall, Jennifer; Stroeven, Arjen; Harbor, Jonathan; Glasser, Neil; Fredin, Ola; Fabel, Derek; Hättestrand, Class; Lifton, Nat

    2016-04-01

    Reconstructing and predicting the response of the Antarctic Ice Sheet to climate change is one of the major challenges facing the Earth Science community. There are critical gaps in our knowledge of past changes in ice elevation and extent in many regions of East Antarctica, including a large area of Dronning Maud Land. An international Swedish-UK-US-Norwegian-German project MAGIC-DML aims to reconstruct the timing and pattern of ice surface elevation (thus ice sheet volume) fluctuations since the mid-Pliocene warm period on the Dronning Maud Land margin of the East Antarctic Ice Sheet. A combination of remotely sensed geomorphological mapping, field investigations, surface exposure dating and numerical modelling are being used in an iterative manner to produce a comprehensive reconstruction of the glacial history of Dronning Maud Land. Here we present the results from the first phase of this project, which involves high-resolution numerical simulations of the past glacial geometries and mapping of the field area using historic and recent aerial imagery together with a range of satellite acquired data.

  8. ABOUT THE INTERNATIONAL GIS WORKSHOPON ANTARCTIC KING GEORGE ISLAND

    2001-01-01

    @@With rapid scientific development and further exploration towards the nature, the human kind hopes to serve themselves by mastering the natural law. Countries all over the world set much value on the study of Antarctica and have obtained plenty and substantial achievements. So as to strengthen mutual understanding among the countries in Antarctic surveying and mapping and share the achievements, the "International GIS Workshop on Antarctic King George Island", Wuhan, July 6th~7th, 2000 was successfully held in the Lecture Hall of the National Laboratory for Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS). It was jointly held by the National Research Center on Antarctic Surveying and Mapping and LIESMARS, and sponsored by the National Polar Region Inspection Office, National Natural Scientific Foundation Committee, the State Bureau of Surveying and Mapping, the former Wuhan Technical University of Surveying and Mapping.

  9. Genetics differentiation between Arctic and Antarctic monothalamous foraminiferans

    Pawlowski, Jan; Majewski, Wojciech; Longet, David;

    2008-01-01

    Monothalamous (single-chambered) foraminifers are a major component of the benthic meiofauna in high latitude regions. Several morphologically similar species are common in the Arctic and Antarctic. However, it is uncertain whether these morphospecies are genetically identical, or whether...... their accurate identification is compromised by a lack of distinctive morphological features. To determine the relationship between Arctic and Antarctic species, we have compared SSU rDNA sequences of specimens belonging to four morphotaxa: Micrometula, Psammophaga, Gloiogullmia, and one morphospecies...... Hippocrepinella hirudinea from western Svalbard (Arctic) and McMurdo Sound (Antarctic). Wherever possible, we include in our analyses representatives of these taxa from the deep Arctic and Southern Oceans, as well as from Northern European fjords. We found that in all cases, the bipolar populations were clearly...

  10. (Environmental impact statement on the US Antarctic program)

    Reed, R.M.; Railsback, S.F.; McLean, R.B.

    1989-12-22

    Three staff members from Oak Ridge National Laboratory (ORNL) participated in a site visit to US Antarctic Program (USAP) facilities at McMurdo Station, Amundsen-Scott South Pole Station, and remote field and support sites. Interviews were conducted with National Science Foundation, Navy, and ITT/Antarctic Services staff responsible for environmental management functions. The ORNL team visited all facilities at McMurdo Station, three remote field camps, a Navy refueling facility, South Pole Station, and Scott Base (a New Zealand installation). In general, the team found that environmental impacts of the USAP are minor for the Antarctic continent as a whole. Improvements for the handling and disposal of solid wastes and the discharge of wastewaters that have been initiated should help minimize environmental impacts of USAP activities. The information collected during the site visit will be used in a draft supplemental environmental impact statement on the USAP to be published for public review in June 1990.

  11. A consistent data set of Antarctic ice sheet topography, cavity geometry, and global bathymetry

    R. Timmermann

    2010-12-01

    Full Text Available Sub-ice shelf circulation and freezing/melting rates in ocean general circulation models depend critically on an accurate and consistent representation of cavity geometry. Existing global or pan-Antarctic topography data sets have turned out to contain various inconsistencies and inaccuracies. The goal of this work is to compile independent regional surveys and maps into a global data set. We use the S-2004 global 1-min bathymetry as the backbone and add an improved version of the BEDMAP topography (ALBMAP bedrock topography for an area that roughly coincides with the Antarctic continental shelf. The position of the merging line is individually chosen in different sectors in order to capture the best of both data sets. High-resolution gridded data for ice shelf topography and cavity geometry of the Amery, Fimbul, Filchner-Ronne, Larsen C and George VI Ice Shelves, and for Pine Island Glacier are carefully merged into the ambient ice and ocean topographies. Multibeam survey data for bathymetry in the former Larsen B cavity and the southeastern Bellingshausen Sea have been obtained from the data centers of Alfred Wegener Institute (AWI, British Antarctic Survey (BAS and Lamont-Doherty Earth Observatory (LDEO, gridded, and blended into the existing bathymetry map. The resulting global 1-min Refined Topography data set (RTopo-1 contains self-consistent maps for upper and lower ice surface heights, bedrock topography, and surface type (open ocean, grounded ice, floating ice, bare land surface. The data set is available in NetCDF format from the PANGAEA database at doi:10.1594/pangaea.741917.

  12. Free amino acids in Antarctic aerosol: potential markers for the evolution and fate of marine aerosol

    E. Barbaro

    2015-01-01

    Full Text Available To investigate the impact of marine aerosols on global climate change it is important to study their chemical composition and size distribution. Amino acids are a component of the organic nitrogen in aerosols, particles containing amino acids have been found to be efficient ice nuclei. The main aim of this study was to investigate the L- and D-free amino acid composition as possible tracers of primary biological production in Antarctic aerosols from three different areas: two continental bases, Mario Zucchelli Station (MZS on the coast of the Ross Sea, Concordia Station at Dome C on the Antarctic Plateau, and the Southern Ocean near the Antarctic continent. Studying the size distribution of amino acids in aerosols allowed us to characterize this component of the water-soluble organic carbon (WSOC in marine aerosols near their source and after long-range transport. The presence of only free L-amino acids in our samples is indicative of the prevalence of phytoplanktonic material. Sampling at these three points allowed us to study the reactivity of these compounds during long-range transport. The mean total amino acid concentration detected at MZS was 11 pmol m−3, a higher percentage of amino acids were found in the fine fraction. The aerosol samples collected at Dome C had the lowest amino acid values (0.7 and 0.8 pmol m−3 and the coarse particles were found to be enriched with amino acids compared to the coastal site. The amino acid composition had also changed suggesting that physical and chemical transformations had occurred during long range transport. During the sampling cruise on the R/V talica on the Southern Ocean, high concentrations of amino acids were found in the total suspended particles, this we attribute to the presence of intact biological material in the sample.

  13. Trematomus bernacchii as an indicator of POP temporal trend in the Antarctic seawaters.

    Cincinelli, Alessandra; Martellini, Tania; Pozo, Karla; Kukučka, Petr; Audy, Ondřej; Corsolini, Simonetta

    2016-10-01

    The occurrence of POPs in remote areas, such as Antarctica, is the result of their ability to udergo Long Range Transport (LRT) in the atmosphere, precipitation and cold condensation. In this study, both recent levels of various POPs in Trematomus bernacchii and their changes in roughly three decades were determined in order to evaluate trends of POPs in Antarctic benthic seawaters. In fact, Trematomus bernacchii is considered a good sentinel bio-indicator for monitoring not only the extent of contamination by POPs in the Antarctic aquatic ecosystem, but also changes in Antarctic ecosystem quality and trends. A slight decreasing PCB trend was detected during 30-years time span (from early 1980's to 2010) in the circumantarctic seawaters. Two higher peaks of concentrations were reported in 2001 and 2005 in the Ross Sea and they may reflect the ice melting of icebergs. Because fire risk is very high in Antarctica due to the very dry air, a large use of flame retardants in buildings and furniture of stations is highly probable; moreover, many stations were built when there were no restrictions on flame retardants use. The PBDE levels in the T. bernacchii from 2001 to 2011 ranged 0.05-0.35 pg/g and were of the same order of magnitude in 2001/2011 and in 2002/2005, with a maximum value in 2005 (0.35 pg/g). Comparable concentrations of HCB, HCHs PCDDs and PCDFs are available only for few seasons: all these compounds showed a decreasing temporal trends and their concentrations were one or more order of magnitude lower in 2000s-2010s.

  14. RTOPO-1: A consistent dataset for Antarctic ice shelf topography and global ocean bathymetry

    Timmermann, Ralph

    2010-05-01

    Sub-ice shelf circulation and freezing/melting rates depend critically on an accurate and consistent representation of cavity geometry (i.e. ice-shelf draft and ocean bathymetry). Existing global or pan-Antarctic data sets have turned out to contain various inconsistencies and inaccuracies. The goal of this work is to compile independent regional fields into a global data set. We use the S-2004 global 1-minute bathymetry as the backbone and add an improved version of the BEDMAP topography for an area that roughly coincides with the Antarctic continental shelf. Locations of the merging line have been carefully adjusted in order to get the best out of each data set. High-resolution gridded data for the Amery, Fimbul, Filchner-Ronne, Larsen C and George VI Ice Shelves and for Pine Island Glacier have been carefully merged into the ambient ice and ocean topographies. Multibeam ship survey data for bathymetry in the former Larsen B cavity and the southeastern Bellingshausen Sea have been obtained from the data centers of Alfred Wegener Institute (AWI), British Antarctic Survey (BAS) and Lamont-Doherty Earth Observatory (LDEO), gridded, and again carefully merged into the existing bathymetry map. The resulting global 1-minute data set contains consistent masks for open ocean, grounded ice, floating ice, and bare land surface. The Ice Shelf Cavern Geometry Team: Anne Le Brocq, Tara Deen, Eugene Domack, Pierre Dutrieux, Ben Galton-Fenzi, Dorothea Graffe, Hartmut Hellmer, Angelika Humbert, Daniela Jansen, Adrian Jenkins, Astrid Lambrecht, Keith Makinson, Fred Niederjasper, Frank Nitsche, Ole Anders Nøst, Lars Henrik Smedsrud, and Walter Smith

  15. Mitochondrial function in Antarctic nototheniids with ND6 translocation.

    Felix C Mark

    Full Text Available Fish of the suborder Notothenioidei have successfully radiated into the Southern Ocean and today comprise the dominant fish sub-order in Antarctic waters in terms of biomass and species abundance. During evolution in the cold and stable Antarctic climate, the Antarctic lineage of notothenioids developed several unique physiological adaptations, which make them extremely vulnerable to the rapid warming of Antarctic waters currently observed. Only recently, a further phenomenon exclusive to notothenioid fish was reported: the translocation of the mitochondrial gene encoding the NADH Dehydrogenase subunit 6 (ND6, an indispensable part of complex I in the mitochondrial electron transport system.This study investigated the potential physiological consequences of ND6 translocation for the function and thermal sensitivity of the electron transport system in isolated liver mitochondria of the two nototheniid species Notothenia coriiceps and Notothenia rossii, with special attention to the contributions of complex I (NADH DH and complex II (Succinate DH to oxidative phosphorylation. Furthermore, enzymatic activities of NADH:Cytochrome c Oxidoreductase and Cytochrome C Oxidase were measured in membrane-enriched tissue extracts.During acute thermal challenge (0-15°C, capacities of mitochondrial respiration and enzymatic function in the liver could only be increased until 9°C. Mitochondrial complex I (NADH Dehydrogenase was fully functional but displayed a higher thermal sensitivity than the other complexes of the electron transport system, which may specifically result from its unique amino acid composition, revealing a lower degree of stability in notothenioids in general. We interpret the translocation of ND6 as functionally neutral but the change in amino acid sequence as adaptive and supportive of cold stenothermy in Antarctic nototheniids. From these findings, an enhanced sensitivity to ocean warming can be deduced for Antarctic notothenioid fish.

  16. Mitochondrial function in Antarctic nototheniids with ND6 translocation.

    Mark, Felix C; Lucassen, Magnus; Strobel, Anneli; Barrera-Oro, Esteban; Koschnick, Nils; Zane, Lorenzo; Patarnello, Tomaso; Pörtner, Hans O; Papetti, Chiara

    2012-01-01

    Fish of the suborder Notothenioidei have successfully radiated into the Southern Ocean and today comprise the dominant fish sub-order in Antarctic waters in terms of biomass and species abundance. During evolution in the cold and stable Antarctic climate, the Antarctic lineage of notothenioids developed several unique physiological adaptations, which make them extremely vulnerable to the rapid warming of Antarctic waters currently observed. Only recently, a further phenomenon exclusive to notothenioid fish was reported: the translocation of the mitochondrial gene encoding the NADH Dehydrogenase subunit 6 (ND6), an indispensable part of complex I in the mitochondrial electron transport system.This study investigated the potential physiological consequences of ND6 translocation for the function and thermal sensitivity of the electron transport system in isolated liver mitochondria of the two nototheniid species Notothenia coriiceps and Notothenia rossii, with special attention to the contributions of complex I (NADH DH) and complex II (Succinate DH) to oxidative phosphorylation. Furthermore, enzymatic activities of NADH:Cytochrome c Oxidoreductase and Cytochrome C Oxidase were measured in membrane-enriched tissue extracts.During acute thermal challenge (0-15°C), capacities of mitochondrial respiration and enzymatic function in the liver could only be increased until 9°C. Mitochondrial complex I (NADH Dehydrogenase) was fully functional but displayed a higher thermal sensitivity than the other complexes of the electron transport system, which may specifically result from its unique amino acid composition, revealing a lower degree of stability in notothenioids in general. We interpret the translocation of ND6 as functionally neutral but the change in amino acid sequence as adaptive and supportive of cold stenothermy in Antarctic nototheniids. From these findings, an enhanced sensitivity to ocean warming can be deduced for Antarctic notothenioid fish.

  17. Antarctic marine biodiversity and deep-sea hydrothermal vents.

    Steven L Chown

    2012-01-01

    Full Text Available The diversity of many marine benthic groups is unlike that of most other taxa. Rather than declining from the tropics to the poles, much of the benthos shows high diversity in the Southern Ocean. Moreover, many species are unique to the Antarctic region. Recent work has shown that this is also true of the communities of Antarctic deep-sea hydrothermal vents. Vent ecosystems have been documented from many sites across the globe, associated with the thermally and chemically variable habitats found around these, typically high temperature, streams that are rich in reduced compounds and polymetallic sulphides. The animal communities of the East Scotia Ridge vent ecosystems are very different to those elsewhere, though the microbiota, which form the basis of vent food webs, show less differentiation. Much of the biological significance of deep-sea hydrothermal vents lies in their biodiversity, the diverse biochemistry of their bacteria, the remarkable symbioses among many of the marine animals and these bacteria, and the prospects that investigations of these systems hold for understanding the conditions that may have led to the first appearance of life. The discovery of diverse and unusual Antarctic hydrothermal vent ecosystems provides opportunities for new understanding in these fields. Moreover, the Antarctic vents south of 60°S benefit from automatic conservation under the Convention on the Conservation of Antarctic Marine Living Resources and the Antarctic Treaty. Other deep-sea hydrothermal vents located in international waters are not protected and may be threatened by growing interests in deep-sea mining.

  18. Wall shear stress in intracranial aneurysms and adjacent arteries

    Fuyu Wang; Bainan Xu; Zhenghui Sun; Chen Wu; Xiaojun Zhang

    2013-01-01

    Hemodynamic parameters play an important role in aneurysm formation and growth. However, it is difficult to directly observe a rapidly growing de novo aneurysm in a patient. To investigate possible associations between hemodynamic parameters and the formation and growth of intracranial aneurysms, the present study constructed a computational model of a case with an internal carotid artery aneurysm and an anterior communicating artery aneurysm, based on the CT angiography findings of a patient. To simulate the formation of the anterior communicating artery aneurysm and the growth of the internal carotid artery aneurysm, we then constructed a model that virtually removed the anterior communicating artery aneurysm, and a further two models that also progressively decreased the size of the internal carotid artery aneurysm. Computational simulations of the fluid dynamics of the four models were performed under pulsatile flow conditions, and wall shear stress was compared among the different models. In the three aneurysm growth models, increasing size of the aneurysm was associated with an increased area of low wall shear stress, a significant decrease in wall shear stress at the dome of the aneurysm, and a significant change in the wall shear stress of the parent artery. The wall shear stress of the anterior communicating artery remained low, and was significantly lower than the wall shear stress at the bifurcation of the internal carotid artery or the bifurcation of the middle cerebral artery. After formation of the anterior communicating artery aneurysm, the wall shear stress at the dome of the internal carotid artery aneurysm increased significantly, and the wall shear stress in the upstream arteries also changed significantly. These findings indicate that low wall shear stress may be associated with the initiation and growth of aneurysms, and that aneurysm formation and growth may influence hemodynamic parameters in the local and adjacent arteries.

  19. Calving fluxes and basal melt rates of Antarctic ice shelves.

    Depoorter, M A; Bamber, J L; Griggs, J A; Lenaerts, J T M; Ligtenberg, S R M; van den Broeke, M R; Moholdt, G

    2013-10-03

    Iceberg calving has been assumed to be the dominant cause of mass loss for the Antarctic ice sheet, with previous estimates of the calving flux exceeding 2,000 gigatonnes per year. More recently, the importance of melting by the ocean has been demonstrated close to the grounding line and near the calving front. So far, however, no study has reliably quantified the calving flux and the basal mass balance (the balance between accretion and ablation at the ice-shelf base) for the whole of Antarctica. The distribution of fresh water in the Southern Ocean and its partitioning between the liquid and solid phases is therefore poorly constrained. Here we estimate the mass balance components for all ice shelves in Antarctica, using satellite measurements of calving flux and grounding-line flux, modelled ice-shelf snow accumulation rates and a regional scaling that accounts for unsurveyed areas. We obtain a total calving flux of 1,321 ± 144 gigatonnes per year and a total basal mass balance of -1,454 ± 174 gigatonnes per year. This means that about half of the ice-sheet surface mass gain is lost through oceanic erosion before reaching the ice front, and the calving flux is about 34 per cent less than previous estimates derived from iceberg tracking. In addition, the fraction of mass loss due to basal processes varies from about 10 to 90 per cent between ice shelves. We find a significant positive correlation between basal mass loss and surface elevation change for ice shelves experiencing surface lowering and enhanced discharge. We suggest that basal mass loss is a valuable metric for predicting future ice-shelf vulnerability to oceanic forcing.

  20. Microbial community composition of transiently wetted Antarctic Dry Valley soils

    Thomas D. Neiderberger

    2015-01-01

    Full Text Available During the summer months, wet (hyporheic soils associated with ephemeral streams and lake edges in the Antarctic Dry Valleys (DV become hotspots of biological activity and are hypothesized to be an important source of carbon and nitrogen for arid DV soils. Recent research in the DV has focused on the geochemistry and microbial ecology of lakes and arid soils, with substantially less information being available on hyporheic soils. Here we determined the unique properties of hyporheic microbial communities, resolved their relationship to environmental parameters and to compared them to archetypal arid DV soils. Generally, pH increased and chlorophyll a concentrations decreased along transects from wet to arid soils (9.0 to ~7.0 for pH and ~0.8 to ~ 5 µg/cm3 for chlorophyll a, respectively. Soil water content decreased to below ~3% in the arid soils. Community fingerprinting-based principle component analyses revealed that bacterial communities formed distinct clusters specific to arid and wet soils; however, eukaryotic communities that clustered together did not have similar soil moisture content nor did they group together based on sampling location. Collectively, rRNA pyrosequencing indicated a considerably higher abundance of Cyanobacteria in wet soils and a higher abundance of Acidobacterial, Actinobacterial, Deinococcus/Thermus, Bacteroidetes, Firmicutes, Gemmatimonadetes, Nitrospira and Planctomycetes in arid soils. The two most significant differences at the genus level were Gillisia signatures present in arid soils and chloroplast signatures related to Streptophyta that were common in wet soils. Fungal dominance was observed in arid soils and Viridplantae were more common in wet soils. This research represents an in-depth characterization of microbial communities inhabiting wet DV soils. Results indicate that the repeated wetting of hyporheic zones has a profound impact on the bacterial and eukaryotic communities inhabiting in these areas.