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101.
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
102.
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
103.
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
104.
105.
An experimental and theoretical identification of hydrodynamic equilibrium for sediment transport and bed response to wave motion are considered. The comparison between calculations and the results of laboratory experiments indicates the linear relation between sediment transport rate and the thickness zm of bed layer in which sediments are in apparent rectilinear motion. This linear relationship allows to use the first order “upwind” numerical scheme of FDM ensuring an accurate solution of equation for changes in bed morphology. However, it is necessary to carry out a decomposition of the sediment transport into transport in onshore direction during wave crest and offshore direction during wave trough. Further, the shape of bed erosion in response to sediment transport coincides with the trapezoid envelope or with part of it, when some sediments still remain within it. Bed erosion area is equal to the one of a rectangle with thickness znm. 相似文献
106.
Seasonal residence and counterurbanization: the role of second homes in population redistribution in Finland 总被引:1,自引:0,他引:1
Since the late twentieth century, many developed countries have experienced population deconcentration, labelled as counterurbanization. There has been an academic discussion on the meaning, validity and universality of this concept, drivers of counterurbanization and its impacts on rural areas. To date, research on counterurbanization mostly apply static and discrete definitions of residence, migration and population, which is an increasingly simplistic view in the contemporary reality of a growing multitude of forms of mobility, often related to dual residence. Particularly large-scale quantitative studies on counterurbanization are confined by existing statistical practices. This paper attempts to overcome this obstacle and describe the transformation of the settlement system in Finland acknowledging the role of second home mobility. To achieve this goal, it introduces two alternative measures of population, seasonal and average population, and analyses their spatial dynamics between the years 1990 and 2010 based on georeferenced grid statistical data. The study finds that although registered population has been concentrating during the period in analysis, seasonal population has been increasingly dispersed due to the growing number of second homes. It shows that the counterurbanization process, though not noticed by conventional statistics, does occur in Finland, manifested by seasonal rather than permanent moves. The article concludes that various forms of mobility should be taken into account when analysing the urban–rural population dynamics and transformations of settlement systems as well as in rural development planning. 相似文献
107.
Marta B?K Lucyna NATKANIEC-NOWAK Beata NAGLIK Krzysztof B?K Pawe? DULEMBA 《《地质学报》英文版》2017,91(1):39-50
An association of organic-walled microfossils consisting of filamentous cyanobacteria, algal coenobia and acanthomorphic acritarch have been documented from non-calcareous claystones and mudstones of the Pepper Mountains Shale Formation(PMSF), located in its stratotype area in the Pepper Mountains, which are part of the Holy Cross Mountains in Poland. These sediments represent the oldest strata of the ?ysogóry Unit, deposited on the edge of the East European Craton(Baltica). Non-branched, ribbon-like and thread-like cyanobacteria trichomes exhibit morphological similarities to families Nostocaceae and Oscillatoriaceae. Cells assembled in rounded to irregular clusters of monospecific agglomerations represent multicellular algal coenobia, attributed to the family Scenedesmaceae. The co-occurrence of acritarchs belonging to species as Eliasum llaniscum, Cristallinium ovillense and Estiastra minima indicates that the studied material corresponds to the lower Middle Cambrian. Deposition of the PMSF took place in shallow marine environment, influenced by periodical freshwater inputs. The varying degree of coloration of organic-walled microfossils is interpreted in this study as factor indication of possible different source of their derivation. Dark brown walls of cells assembled in algal coenobia might have sustained previous humification in humid, terrestrial environments, which preceded their river transport into the sea together with nutrients, causing occasional blooms of cyanobacteria in the coastal environment and the final deposition of both groups of organisms in marine deposits. 相似文献
108.
Oskar Bojko Cezary Kabala Łukasz Mendyk Maciej Markiewicz Magdalena Pagacz-Kostrzewa Bartłomiej Glina 《山地科学学报》2017,14(12):2391-2405
Global and local climate changes could disturb carbon sequestration and carbon stocks in forest soils. Thus, it is important to characterize the stability of soil organic matter and the dynamics of soil organic carbon (SOC) fractions in forest ecosystems. This study had two aims: (1) to evaluate the effects of altitude and vegetation on the content of labile and stabile forms of organic carbon in the mountain soils; and (2) to assess the impact of the properties of soil organic matter on the SOC pools under changing environmental conditions. The studies were conducted in the Karkonosze Mountains (SW Poland, Central Europe). The content of the most labile fraction of carbon (dissolved organic carbon, DOC) decreases with altitude, but the content of fulvic acids (FA), clearly increases in the zone above 1000 m asl, while the stabile fraction (humins, non-hydrolyzing carbon) significantly decreases. A higher contribution of stabile forms was found in soils under coniferous forests (Norway spruce), while a smaller - under deciduous forests (European beech) and on grasslands. The expected climate change and the ongoing land use transformations in the zone above 1000 m asl may lead to a substantial increase in the stable humus fraction (mainly of a non-hydrolyzing carbon) and an increase in the SOC pools, even if humus acids are characterized by a lower maturity and greater mobility favorable to soil podzolization. In the lower zone (below 1000 m asl), a decrease in the most stable humus forms can be expected, accompanied by an increase of DOC contribution, which will result in a reduction in SOC pools. Overall, the expected prevailing (spatial) effect is a decreasing contribution of the most stable humus fractions, which will be associated with a reduction in the SOC pools in medium-high mountains of temperate zone of Central Europe. 相似文献
109.
P.A. Przybylski E. Głowniak J.G. Ogg P. Ziółkowski M. Sidorczuk J. Gutowski M. Lewandowski 《Earth and Planetary Science Letters》2010,289(3-4):417-432
A nearly continuous magnetostratigraphic polarity pattern was compiled from several ammonite-zoned carbonate successions of southern Poland and from a composite magnetostratigraphy from the Iberian Range of Spain. The array of sections spans the middle two-thirds of the Oxfordian within the Sub-Mediterranean Province (Cordatum through Bifurcatus ammonite zones). The average paleopole calculated from eight of these Polish sections is at 78.5°N, 184.9°E (δp = 2.6°, δm = 3.5°). The Sub-Mediterranean polarity pattern is consistent with an independent polarity pattern derived from the Boreal-realm sections of the British Isles, and improves the inter-correlation between these faunal realms. Cycle stratigraphy published for these ammonite subzones from southern France enabled temporal scaling of the polarity pattern, thereby facilitating correlation to marine magnetic anomalies M28 through M33 as modeled from deep-tow magnetometer surveys in the Western Pacific. The bases of the Middle and Upper Oxfordian substages as defined in the Sub-Mediterranean zonation in Poland correspond approximately to chrons M33 and M29 of that Pacific M-sequence model. 相似文献
110.
Pawe? Koperski 《Limnologica》2010,40(3):233-240
Reduced biological diversity in freshwater habitats situated in urban areas has been discussed in numerous studies. Certain municipal areas, however, can help save animal diversity of freshwater invertebrates. In the present study animals were collected or observed alive in 13 freshwater environments localized in Warsaw - the second largest city of Central Europe - in a densely populated, urban building complex close to the city, and also in suburban areas. Leech assemblages in all the environments under observation were numerically dominated by a few common species, but on the whole 19 species were collected or observed. The populations of six rare leech species inhabit both flowing and standing waters in Warsaw. Five of these species are on the Polish Red List of Species and one is strictly protected. The shallow Lake Powsinkowskie is the richest freshwater environment in the studied area in terms of species richness and rarity and also one of the richest lakes in Poland. Taxonomic diversity in the environments under study seems not to be directly related to the size of the water body or the level of degradation but rather to the habitat complexity, especially the diversity of the bottom in littoral zone. Certain freshwater habitats located inside this great urban complex still create good conditions for rare, highly specialized species. 相似文献