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61.
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
62.
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
63.
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
64.
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
65.
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
66.
67.
In 2011, a geophysical survey was carried out in the surroundings of the Jagiellonian University in Cracow, using a Very Low Frequency method. The measurements were designed to determine the reason of frequent flooding of the lowest level of the building. The main objective of the study was to find out from where and in which way the rainwater seeps into the building and how this problem can be solved in the least invasive manner. The aim of geophysical methods was also to provide necessary information that will enable the construction of a hydro-geological model of the local environment. The interpretation revealed the presence of a sandy gutter surrounded by impermeable clay. There is a big resistivity contrast between those layers. Their location and approximate dimensions were determined. 相似文献
68.
An analysis of linear relationships between the ground-level components of the Earth’s magnetic field measured at different sites is a relatively new topic compared to the analysis of data at a single location. The data collected by the INTERMAGNET observation network provide perfect set of data to which this analysis can be used. An important tool in this analysis may be developing a method of determination of the impulse response for linear systems in the time domain. An advantage of calculations in the time domain over the generally known and applied methods in the frequency domain is the possibility of determining prediction of output signals. By that, simultaneously with the analysis of linear relationships, a tool for recovering missing records in incomplete observation data is obtained. Filling-in the missing data may increase interest and possibility of using the observational data by researchers experimenting with the analysis in the frequency domain where gaps in data records are a significant limitation. 相似文献
69.
70.
Lech Krysiński 《Pure and Applied Geophysics》2009,166(3):375-408
The paper describes a new method of gravity modelling of the density cross section along a DSS profile. We propose a systematic
procedure of gravity interpretation using structural information contained both in the velocity distribution of the seismic
model and the geometry of its layers. The procedure is based on the optimisation of the density parameters of the model. The
values of the parameters are limited by relationships between the seismic velocity and the density (optimisation with inequalities).
The formulation of the method allows for discussion of the presence of isostasy and the distribution of compensating masses.
The discussion is very important for the considered crust-lithosphere system. The presented calculations are done for one
Carpathian profile (CEL01). The analysis of the properties of the fitting procedure provides the characteristic depth of subcrustal
compensating density structures, the position of crucial tectonic boundaries along the profiles, locations of the crustal
areas having exceptional lithology, the regional density differences of subcrustal matter and the estimation of regional deviations
from the isostatic equilibrium. 相似文献