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201.
Influence of arsenic-bearing gold deposits on water quality in Zloty Stok mining area (SW Poland) 总被引:3,自引:2,他引:1
The Sudety Mountains contain polymetallic deposits which have been exploited since the Middle Ages. Distinct concentrations
of As, Hg, F, Cr in surface water near Zloty Stok suggested that groundwater in the area could also contain elevated metal
concentrations. Water samples from 15 locations including Zloty Stream, mine adit discharges, and selected springs generally
show low levels of dissolved components and near-neutral pH. However, arsenic concentrations range from 0.99 mg/l to 26.16 mg/l
at all 15 sample locations. Mercury concentrations were locally as high as 0.011 mg/l. These high arsenic and mercury concentrations
significantly exceed water quality standards and raise concerns for using Zloty Stream for potable water.
Recieved: 21 December 1998 · Accepted: 8 June 1999 相似文献
202.
Małgorzata Pisarska‐Jamroży Tomasz Zieliński 《Boreas: An International Journal of Quaternary Research》2014,43(2):330-348
The Drawa sandur, which is the largest, coarse‐grained sandur in Poland, dates from the Pomeranian phase of the Weichselian glaciation (c. 16 ka BP). Using Markov chain analysis we infer that five cycles and five rhythms occur in its proximal part. The cycles dominated by Gt and St lithofacies in the lower part of the sandur succession and by a GDm lithofacies in the upper part, are fining‐upward cycles deposited in braided channels during large ablation floods. Three groups of cycles are distinguished based on their genesis: (i) cycles due to channel‐sheet evolution during large floods; (ii) cycles due to braid‐bar development during initial and advanced diminishing of floods; and (iii) cycles developed in the thalweg or interbar channels. The succession as a whole forms a large‐scale coarsening‐up megacycle (‘sandur megacycle’) which corresponds to a phase of ice‐sheet advance. Because the cyclicity was evident from Markov chain analysis of the sedimentary succession, we suggest that this statistical tool is valuable for reconstruction of glacifluvial sedimentary conditions, particularly as it can shed new light on the palaeogeographical development of sandar. 相似文献
203.
204.
Winter weather conditions vs. air quality in Tricity,Poland 总被引:1,自引:1,他引:0
Jadwiga Nidzgorska-Lencewicz Małgorzata Czarnecka 《Theoretical and Applied Climatology》2015,119(3-4):611-627
205.
206.
Łukasz Stachnik Piotr Wałach Łukasz Uzarowicz Jacob C. Yde Zornitza Tosheva Dominika Wrońska-Wałach 《山地科学学报》2014,11(5):1097-1111
This study aims to determine the relationships between local meteorological conditions,proglacial river discharge and biogeochemical processes operating in a periglacial basin located in the Polar Ural mountain range, Russia. Fieldwork was conducted in the catchment of Obruchev Glacier(13 km2) during the summer peak flow period in 2008. River discharge was dominated by snowmelt and changed from 3300 l s-1 to less than 1000 l s-1. The mean daily air temperatures of stations situated in the mountain tundra and near Obruchev Glacier from July 11 th to August 1st 2008 were 14.4°C and 10.3°C, respectively. The glacial river had low total dissolved solids varying from 4.5 to 9 mg l-1 and coefficients of correlation between Na+ and Cl-, K+ and Cl-, as well as NH4+ and Cl- were 0.94, 0.90 and 0.84, respectively. Rainfall events affected the snowmelt initiation and provided an essential part of the discharge during the intense snowmelt period, which occurred from July 11 th to July 18 th 2008. Data showed that Na+ and K+ in the surface water derived from snowmelt rather than chemical weathering of silicates. Also, it was obtained that NO3- derived from the melting snowpack, whereas ammonification occurring under the snowpacks was the primary source for NH4+. 相似文献
207.
Six variations of multiplicative random cascade models for generating fine-resolution (i.e., 5-minute interval) rainfall time series were evaluated for rainfall in Wroclaw, Poland. Of these variations, one included a new beta-normal generator for a microcanonical cascade. This newly proposed model successfully reproduces the statistical behavior of local 5-minute rainfalls, in terms of intermittency as well as variability. In contrast, both the canonical cascade models with either constant or time-scaled parameters and a microcanonical cascade model with a beta generator substantially underestimate 5-minute maximum rainfall intensities. The canonical models also fail to properly reproduce the intermittency of the rainfall process across a range of timescales. New observations are also made concerning the histograms of the breakdown coefficients (BDC). The tendency of the BDC histograms to have values exactly equal to 0.5 is identified and explained by the quality of pluviograph records. Moreover, the hierarchical evolution of BDC histograms from beta-like for long time steps to beta-normal histograms for short time steps is observed for the first time. The potential advantage is shown of synthetic high resolution rainfall time series generated by the revised microcanonical model for use in hydrology, especially hydrodynamic modelling of urban drainage networks. 相似文献
208.
Leszek R. Jaroszewicz Zbigniew Krajewski Henryk Kowalski Grzegorz Mazur Paweł Zinówko Jerzy Kowalski 《Acta Geophysica》2011,59(3):578-596
We outline the research leading to development of the Autonomous Fibre-Optic Rotational Seismograph (AFORS) and describe the
final version of the instrument. The instrument with linear changes of sensitivity keeps accuracy from 5.1 × 10−9 to 5.5 × 10−8 rad/s in the detection bandpass 1.66–212.30 Hz; it is designed for a direct measurement of rotational components emitted
during seismic events. The presented system is based on the optical part of the fibre optic gyro construction where a special
autonomous signal processing unit (ASPU) optimizes its operation for the measurement of rotation motions instead of the angular
changes. The application of a newly designed telemetric system based on the Internet allows for a remote system control, as
shown in an example of the system’s operation in Książ (Poland) seismological observatory. 相似文献
209.
The main focus of this paper is calculation of the diameters of asteroids belonging to five families (Vesta, Eos, Eunomia, Koronis, and Themis). To do that, we used the HCM algorithm applied for a data set containing 292,003 numbered asteroids, and a numerical procedure for choosing the crucial parameter of the HCM, called “the cutting velocity” vcut. It was established with a precision as high as 1 m s?1. Thereafter, we used the WISE (Wide‐field Infrared Survey Explorer) catalog to set a range of albedo for the largest members of each family considered. The albedo data were supported by the data concerning color classification (SDSS MOC4). The asteroids with albedo out of this range were classified as interlopers and were therefore disqualified as family members. Sizes were calculated for the asteroids with albedo within the acceptable range. For the other asteroids (those chosen by means of the HCM, but with albedo not listed in the WISE), the value of albedo of the largest member of the family was adopted. Results are given in a set of figures showing the families on the planes (a, e), (a, i), (e, i). Diameters and volumes of the asteroids that are the individual members of a family were calculated on the basis of their known or assumed albedo and on their absolute magnitude. Volumes of the parent bodies of the families were found on the basis of the cumulative volume distribution of these families. We also studied the secular resonances of the family members. We have shown that the locations of members of the considered asteroid families are related to the lines of secular resonances z1, z2, and z3 with Saturn. 相似文献
210.
Karol Kozieł 《Earth, Moon, and Planets》1979,21(3):351-359
This paper presents historical stages of the development of methods concerning observation and theory of the Moon's rotation around its centre of mass from the beginning of the 17th century up to the present day. The accuracy and usefulness of these methods is estimated and a critical attitude is assumed towards the results concerning the values of constants of the Moon's physical libration. 相似文献