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91.
Coastal lakes have a specific hydrological regime determined by the influence of sea and inland water and the local hydrographic conditions. There are several problems concerning the protection and assessment of water quality of these bodies. The most important features differentiating coastal lakes from other lakes are: high salinity, a wide range of seasonal and short-term water quality changes, and specific aquatic ecosystems adapted to these conditions. These matters have not been sufficiently taken into account in the existing classifications and typologies of lakes in Poland. The problem has not been solved by the establishment of the adequate reference conditions and new guidelines for the classification of water status (which are being prepared according to the Common Strategy for the Implementation of the Water Framework Directive) regarding inland surface waters (rivers and lakes) and marine waters (coastal and transitional). An important issue is to define criteria which would help to distinguish all those hydrographic objects and to establish water quality standards for them. 相似文献
92.
Mineral constituents in common chanterelles and soils collected from a high mountain and lowland sites in Poland 总被引:1,自引:1,他引:0
This paper reported the results of the determination of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn in Common Chanterelles (Cantharellus cibarius) Fr. and surface soil layer (0-10 cm) underneath the fruiting bodies. Mushrooms and soils were collected from a lowland site in the Hel Peninsula (Baltic Sea coast) and a high mountain site in the Tatra Mountains. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES). Common Chanterelles that emerged at sites poor in mineral nutrients podzols of the Hel Peninsula forests efficiently bioconcentrated several essential trace elements (K, P, Co, Cu, Mn, Na, Zn), while the abundance of those elements in carpophores was around half less compared to specimens from Zakopane region and which emerged in soils much richer in minerals. Common Chanterelles collected at two spatially distant background areas in Poland were only weakly contaminated with metals such as Ag, Cd, Hg and Pb. The maximum tolerable Cd and Pb contents of certain cultivated mushrooms are regulated in the European Union by law and these hazardous metals in C. cibarius were far below tolerance limits set. 相似文献
93.
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
94.
Krzysztof Kroszczyński 《Acta Geophysica》2015,63(4):1126-1149
The paper presents the results of analyses of numerical experiments concerning GPS signal propagation delays in the atmosphere and the discrete mapping functions defined on their basis. The delays were determined using data from the mesoscale non-hydrostatic weather model operated in the Centre of Applied Geomatics, Military University of Technology. A special attention was paid to investigating angular characteristics of GPS slant delays for low angles of elevation. The investigation proved that the temporal and spatial variability of the slant delays depends to a large extent on current weather conditions. 相似文献
95.
Several researches published comprehensive reports on dynamic soil properties of cohesive soils, in which many of them outlined, i.e., key factors affecting the dynamic shear modulus. For cohesive soils, the modulus at small strains (g < 10t-3 %) is, first of all, a function of void ratio and effective confining stress. For clays, however, secondary time effects and clay mineralogy (fabric and structure) also appear to be important. The influence of confinement of laboratory-prepared as well as naturally deposited clays consists in an increase of shear modulus logarithmically as a function of time. In this paper, the effect of duration of the various confining pressures on dynamic shear modulus (G) of selected cohesive soils from Warsaw area was evaluated. Shear modulus was determined on the basis of resonant column tests, at low and high shearing strain amplitudes. It is shown that the calculated shear modulus is time-dependent; during approximately first 1000 minutes of consolidation, the moduli increased by almost 50%. Moreover, it is characterized by two phases: an initial one results from primary consolidation and a second one, which occurs after the end of primary consolidation, herein about 16-17 hours, and is called “long-term time effect”. This effect was found also for modulus at higher shearing strains (γ > 103%, e.g., 3 × 103%, 5 × 103%, 8 × 103%, 2 × 103%). 相似文献
96.
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
97.
A. Szczucińska 《Geochemistry International》2017,55(12):1164-1170
Hydrogeochemical background determined for an investigated environment, defines characteristic range of its hydrochemical characteristics. This allows to observe the temporal changes of the chemical water properties taking place in the studied environments, such as due to human impact. The paper presents the results of study on the present-day hydrogeochemical background in the Lubuskie Lakeland, the region repeatedly covered by the ice sheets during the Pleistocene and little affected by anthropogenic impact. The hydrogeochemical background was established on a basis of physicochemical analyses of spring waters sampled every 3 months between November 2011 and October 2013 from 20 springs. Present-day hydrogeochemical background was assumed to be represented by values ranging between 16 and 84 percentiles. The ranges of hydrogeochemical background for the studied ions on the Lubuskie Lakeland, were in the lower range of the background considered for useful waters in Poland. The obtained results indicated that the studied spring waters were poorly diversified in terms of composition of main cations and anions, as well as electrical conductivity and total water hardness. However, large variability was observed for Fetot, Mn2+ and NO3?. Moreover, NO3? and SO42? were noted in some cases to be in excess of national hydrogeochemical background values. 相似文献
98.
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
99.
New marine ΔR values for Arctic Canada 总被引:1,自引:0,他引:1
Roy D. Coulthard Mark F.A. Furze Anna J. Pieńkowski F. Chantel Nixon John H. England 《Quaternary Geochronology》2010,5(4):419-434
For more than four decades, the reporting of 14C dates on marine molluscs from Arctic Canada has been notable for the lack of consistently applied marine reservoir corrections. We propose that the common approach of reporting Canadian Arctic marine 14C dates using presumed time-invariant reservoir corrections be abandoned in favour of calibration of 14C dates, using the current standard protocol. This approach best facilitates inter- and intra-regional correlation, and correlation with other geochronometers. In order to enable the consistent calibration of marine 14C dates from Arctic Canada, we analysed a 14C database of 108 marine mollusc samples collected live between 1894 and 1956, and determined regional reservoir offset values (ΔR) for eight oceanographically distinct regions. The following new ΔR values should be used for 14C calibration: NW Canadian Arctic Archipelago, 335 ± 85 yrs; Foxe Basin, 310 ± 90 yrs; NE Baffin Island, 220 ± 20 yrs; SE Baffin Island, 150 ± 60 yrs; Hudson Strait, 65 ± 60 yrs; Ungava Bay, 145 ± 95 yrs; Hudson Bay, 110 ± 65 yrs; and James Bay, 365 ± 115 yrs. 相似文献
100.