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131.
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133.
Grzegorz Karasiński Michał Posyniak Magdalena Bloch Piotr Sobolewski Łukasz Małarzewski Jakub Soroka 《Acta Geophysica》2014,62(2):316-339
Two significant volcanic eruptions, i.e., Eyjafjallajökull (April–May 2010) and Grímsvötn (May 2011) took place recently in Iceland. Within a few days after eruptions, layers of high aerosol concentration have been observed by multiwavelength lidar of the Polish Polar Station at Hornsund, Svalbard. Measurements of the aerosol’s optical properties indicated a possible presence of volcanic ash transported over the Station. The latter presumption was confirmed by the computed backward trajectories of air masses, showing their paths passing over the location of volcanoes. 相似文献
134.
M. Jamrozy D. Kozieł-Wierzbowska S. Zoła A. Kuźmicz J. Machalski 《Journal of Astrophysics and Astronomy》2011,32(4):467-470
J1159+5820 is an extended radio galaxy with a quite unusual morphology, featuring two pairs of radio lobes. Such sources,
called double–double radio galaxies, constitute a very rare class of extragalactic radio sources. Furthermore, the extended
radio structure of this source shows an X-shape form. According to a much likely scenario, such a morphology is due to interrupting
nuclear activity in its central active galactic nucleus. Interestingly, the host of this source is a near-distance bright
galaxy named CGCG 292-057, which is clearly disturbed, with tidal features and shells as plausible signs of a recent merger. 相似文献
135.
ZHANG Dan ZHANG Yu MORAWSKA Ewa BIELAWSKI Leszek KRASINSKA Grazyna DREWNOWSKA Ma gorzata PANKAVEC Sviatlana SZYMANSKA Karolina FALANDYSZ Jerzy 《山地科学学报》2013,10(4):621-627
In the current study, we determined concentrations and transfer rates of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn to Brown Birch Scaber Stalks (Leccinum scabrum) mushrooms emerged in the area of Sudety Mountains (Sudetes) in Poland. Fruiting bodies and topsoil samples beneath L. scabrum were collected form the K odzka Dale. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES) for final measurement. Mushrooms contained Ag, Cr, Hg, Co, Ni and Sr at < 1.0 μg/g dry weight; Ba and Pb at ~1.0 μg/g dw; Cd at < 5 μg/g dw; Cu and Mn at > 10 μg/g dw; Al and Ca at ~100 μg/g dw; Fe, Na, Rb and Zn at 100 to 500 μg/g dw, Mg at ~1,000 μg/g dw; P at ~5,000 μg/g dw and K at ~30,000 μg/g dw. Ca, Mn and Ni were nearly equally distributed between stipes and caps; stipes compared to caps were enriched in Ba, Na and Sr, while caps were enriched in Ag, Al, Cd, Co, Cr, Cu, Fe, K, P, Pb, Rb and Zn. The values of bioconcentration factor (BCF) varied highly depending on chemical element and were >1 for Ag, Cd, Cu, K, Mg, Na, P, Rb and Zn, while <1 for Al, Ba, Ca, Co, Cr, Fe, Mn, Ni, Pb and Sr. Topsoil showed elevated content of lead and mean concentration was 99 ± 32 μg/g dw, while cadmium was at 0.41 ± 0.15 and those two highly toxic to human elements occurred in edible caps of L. scabrum at 4.5 ± 2.2 and 2.9 ± 2.0 μg/g dw, respectively. 相似文献
136.
Environmental change,hydromorphological reference conditions and the restoration of Polish Carpathian rivers 总被引:1,自引:0,他引:1
Bartłomiej Wyżga Joanna Zawiejska Artur Radecki‐Pawlik Hanna Hajdukiewicz 《地球表面变化过程与地形》2012,37(11):1213-1226
In the twentieth century Polish Carpathian rivers were considerably modified by channelization and gravel mining, with significant detrimental effects to their ecological integrity, vertical stability of the streambeds and flood hazard to downstream river reaches. Restoration of the rivers is thus necessary to improve their ecological status and re‐establish geomorphic dynamic equilibrium conditions. Various approaches to defining hydromorphological reference conditions, proposed to date in river restoration literature, have serious deficiencies. In particular, environmental changes that took place in the catchments of Carpathian rivers during the twentieth century invalidate the historical state of the rivers as reference for their restoration. This is illustrated by a change from bar‐braided to island‐braided channel pattern that occurred in the past century in unmanaged sections of the Czarny Dunajec in response to a reduction in flow and sediment dynamics of the river. We indicate that reference conditions should be defined as those which exist or would exist under present environmental conditions in the catchment but without human influence on the channel, riparian zone and floodplain of the river which is to be restored. This assumption was tested through the evaluation of hydromorphological river quality of the Czarny Dunajec according to the European Standard EN‐14614. The evaluation confirmed a high‐status hydromorphological quality in an unmanaged channel section, which can thus be used as a reference for restoration of impacted river sections. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
137.
Marine populations in Europe are in decline due to the unsuccessful results of the Common Fisheries Policy. By combining data of scientific recommendations from ICES, TACs approved and reported landings with an age-structured model, the objectives of this paper are to investigate the level of compliance of the TAC regulation, and the level of enforcement and its economic impact on fishery resources. The results presented here suggest that while there does not exist a regular pattern between TAC proposal and TAC approved, there is a clear pattern between TAC approved and reported landings. As a consequence, there is a regular lack of enforcement at national fisheries authority level. The paper also presents results of the recovery plans for the Southern hake and the Atlantic cod fisheries as case studies to illustrate the level of enforcement based on collusion between national fisheries advisers and industry. The results from both cases studies analyzed here indicate that drastic solutions could generate positive results for the recovery of the stocks, but perhaps they are not always the best measure in fisheries management due to the high economic losses for fishermen and social effects on coastal communities in the short and medium term. Finally, this work demonstrates that if the recovery plans had been implemented, the net present profits for both fisheries would have increased over time. 相似文献
138.
Sebastian?WetterichEmail author Lutz?Schirrmeister Hanno?Meyer Finn?Andreas?Viehberg Andreas?Mackensen 《Journal of Paleolimnology》2008,39(4):427-449
The aim of this study is to describe ostracods from freshwater habitats in the Siberian Arctic in order to estimate the present-day
relationships between the environmental setting and the geochemical properties of ostracod calcite. A special focus is on
the element ratios (Mg/Ca, Sr/Ca), and the stable isotope composition (δ18O, δ13C), in both ambient waters and ostracod calcite. The most common species are Fabaeformiscandona pedata and F. harmsworthi with the highest frequency in all studied waters. Average partition coefficients D(Sr) of F. pedata are 0.33 ± 0.06 (1σ) in females, and 0.32 ± 0.06 (1σ) in males. A near 1:1 relationship of δ18O was found, with a mean shift of Δmean = 2.2‰ ± 0.5 (1σ) to heavier values in ostracod calcite of F. pedata as compared to ambient waters. The shift is not dependent on δ18Owater, and is caused by metabolic (vital) and temperature effects. Temperature-dependence is reflected in the variations of this
shift. For ostracod calcite of F. pedata a vital effect as compared to inorganic calcite in equilibrium was quantified with 1.4‰. Results of this study are valuable
for the palaeoenvironmental interpretation of geochemical data of fossil ostracods from permafrost deposits. 相似文献
139.
140.
Jan Wiszniowski Nguyen Van Giang Beata Plesiewicz Grzegorz Lizurek Dinh Quoc Van Le Quang Khoi Stanisław Lasocki 《Acta Geophysica》2015,63(3):843-862
Song Tranh 2 hydropower plant and the reservoir containing backed up water are located in the Quang Nam province (Central Vietnam). The region experiences unusual seismic activity related to the reservoir impoundment, with earthquakes of magnitude up to 4.7. In result of cooperation between the Institute of Geophysics, Vietnam Academy of Sciences and Technology and the Institute of Geophysics, Polish Academy of Sciences a seismic network has been built to facilitate seismic monitoring of the Song Tranh 2 area. The network, operating since August 2013, consists of 10 seismic stations. Here we show that the network is sufficient for advanced data processing. The first results of monitoring of the earthquake activity in Song Tranh 2 area in the period between 2012 and 2014, especially the completeness of catalogs, study and comparisons between water level and the seismic activity suggest direct connection between reservoir exploitation and anthropogenic seismicity. 相似文献