The results of studies of radioactive contamination of Borne Sulinowo military range is presented. Until 1991, this area was occupied by the former Soviet Army. No serious contamination with natural or artificial radionuclides has been found in the studied area. The activity of natural radionuclides such as 214Bi, 226Ra, 234Th, 224Ra, 228Ac and 214Pb in the soils ranges from 6-8 Bq/kg of soil, which is low when compared to industrial regions of Poland, where 18-36 Bq/kg of these radionuclides have been found. Also, contamination by 137Cs is considerably lower than in Eastern Poland. In about 70% of the studied samples, post-Chernobyl radiocesium contributed less than half of the total amount of this nuclide. It follows that post-Chernobyl fallout was low in the studied area. Moreover, the high level of l37Cs from global fallout in the examined samples manifests strong bonding of cesium in the surface layer of the soil.
This paper presents the results of determination of artificial 137cs and natural 40K activity concentrations and some heavy metals in soil samples from the region of one of the main valleys of Tatra National Park (Chochołowska). Our investigation concentrated on 137Cs and heavy metal levels in mountain soil taken from Chochołowska Valley, which revealed great variability in their concentration. The results show considerably small amounts of radionuclides 137cs and 40K in the soils. Larger amounts of those elements can be found in the organic surface horizons of the soils. The evaluation of the content of those elements must be based on the bulk density analysis of the soil.
This study presents the results of determinations of Cs-137 in full-fat cow milk powder originating from four regions of Poland. The assays performed demonstrated differences in the content of Cs-137 in milk powder depending on the region. The higher content of Cs-137 was found in powdered milk samples collected from Opole (3.50 Bq/dm³). The lowest content of Cs-137 was in milk samples from Września (0.98 Bq/dm³). In powdered milk samples from Łapy and Krotoszyn the amount of Cs-137 was 2.02 and 1.11 Bq/dm³, respectively. The average content of Cs-137 in full-fat cow milk powder from all examined regions was 1.90 Bq/dm³ after reconstituting to liquid milk, and did not exceed the admissible level of Cs-137 in food.
Recent sediment accumulation rates in Adventfjorden (Svalbard), a small subpolar fjord, were determined by 210Pb and 137Cs dating. Modern rates in the central basin decrease downfjord from 1.87 to 0.87 cm y−1 (2.6 to 1.19 g cm−2 y−1). Comparison of the modern values (1986–2001) with older ones (1963–86) reveals a marked increase in sediment accumulation rates in the last ten years. This correlates well with recent climate changes (warming and increase in precipitation). Comparison with particulate matter flux data indicates that a portion of the sediment is passed on to Isfjorden.
Studies of the contents of gamma emitters in samples of water and deposit taken from the Bug River (in Poland only) are presented. The total y-activity of deposits ranges from 120-650 Bq/kg and the average value is 350 Bq/kg. The elevated activity is chiefly due to the presence of natural radionuclides. The main artificial radionuclides are Cs-137 and Cs-134, whose contribution to the total activity ranges from 0.2 to 6%. The activity of water samples is low, namely 1.7-3.5 Bq/kg and is due to the presence of natural radionuclides. The heterogeneity of the distribution of natural and artificial radionuclides in the studied samples reveals the effect of economical and industrial activities on contamination of the Bug.
This paper presents the results of investigations of grass contaminated by 137Cs in eastern Poland. The influence of the site, potassium ion content, soil type and caesium from soil to plant transfer coefficient (TF) were examined.
This paper encloses results of field tests carried out on two types of organic soils. Activities of caesium, originating from global fallout as well as from the Chernobyl power plant breakdown, were measured for these two soils. Radioactive caesium is present to a depth of 40 and 70 cm, in black soil and in peat, respectively, although the highest activity was found in the topmost layers. Caesium originating from the Chernobyl accident constitutes about 70% of the total activity in the 0-10 cm layers of the soils. The vertical migration rates of caesium from both sources were also measured. In the case of peat soil the migration rate of the Chernobyl caesium as well as that from global fallout were found to be similar and amounted to 0.2 cm/year. In the case of black soil the differences were more pronounced (0.34 and 0.14 cm/year, respectively). Results of the physicochemical analysis of both tested soils are also included in this work.
The contamination of the city of Lublin by gamma emitters and contents of radionuclides in the ground layer of air were studied. A heterogeneous distribution of radiocesium was found in soils, due chiefly to the Chernobyl power plant accident The contribution of afiter-Chernobyl radiocesium to the total amount of this radioelement in the surface layer of the soil averages 85%. Compared with so-called uncontaminated areas, there is an elevated level of the natural nuclides Ra-226, Ra-224, Ac-228, Pb-212 and Bi-212 in the city. However, potassium-40, whose contribution averages about 65% of total activity, is the main gamma emitter found in Lublin soil. In grass samples, the contribution of K-40 averages as high as 85%. Substantial amounts of Ra-226 and Ra-224 were also found in grass. Radiocesium activity in grass ranges from 0.6 to 11 Bq/kg of dry matter and the transfer factor of Cs-137 from soil to grass ranges from 0.07 to 0.85. The radioactivity of the ground layer of air was as low as 1.2 — 3.4 mBq/m3.
This paper presents the results of determinations of radiocesium and plutonium activity concentrations and some heavy metals in soil samples from two main Tatra Valleys: Kościeliska and Rybi Potok Valley. The results were obtained during 2001. It has been found that the content of 137Cs and 239+240Pu is much higher at altitudes over 1300 m asl.
The concentrations of gamma emitters in grass samples of central-eastern Poland have been determined. The transfer factors for Cs-137 were calculated for particular samples. The effects of soil type, location of the sampling points and of potassium concentration on this transfer factor were studied.
The study examines the transfer factor (TF) for cesium in a soil-plant system and cesium accumulation in cress Lepidium sativum L. plants grown in hydroponic culture and subjected to root and foliar application of 0.3 mM CsCl. The experiments showed a high TF for radiocesium: 2.97 (kBq/kg plant DW)/(kBq/kg soil DW). High accumulation of cesium was observed in leaves after both root and foliar treatments. A higher concentration of cesium (3 mM) caused significant disturbance in water uptake, tissue hydration (FW/DW) and production of biomass (DW). Accumulation of cesium in leaves affected gas exchange parameters. Stomatal conductance (C) and transpiration rate (E) were strongly inhibited but photosynthetic CO2 assimilation (P) was disturbed to a lesser extent. As a result, photosynthetic water utilization efficiency (P/E) was unaffected by 3 mM cesium at photosynthetically active radiation (PAR) of 220 µmol x m-2 x s-1. Increasing PAR from 220 to 450 µmol x m-2 x s-1 stimulated the photosynthetic rate after 3 days, but no stimulation was observed after 5 days of cesium treatment, in comparison with potassium-grown plants. Changes in chlorophyll fluorescence, indicating maximal quantum yield of photosystem II (PSII) photochemistry, were observed only as a late stress effect. Decreased stomatal opening was an early effect of cesium stress in Lepidium sativum, which resulted in limitation of transpiration and water uptake. It is suggested that the decrease in tissue hydration is what limits photosynthetic CO2 assimilation, synthesis of organic matter and light reactions of photosynthesis.
The influence of soil micromycetes (melanin-containing, dark-pigmented Cladosporium cladosporioides and light-pigmented Paecilomyces lilacinus) on 137Cs accumulation by aboverground phytomass of some higher plants (sugar beet, cabbage and clover) was studied in field experiments in radionuclides contaminated soil of the Chernobyl zone with total radioactivity 37-50 kBq kg⁻¹. Abundance of these fungi was determined 1,3 and 5 months after their introduction into the soil. P. lilacinus colonies were isolated in the beginning of the experiment in contrast to C. cladosporioides colonies that were isolated at the end of plants vegetation. The coefficients of [izotop cezu 137] accumulation by aboveground phytomass were higher after the introduction of light-pigmented than of dark-pigmented fungus. These coefficients were higher after the simultaneous introduction of the two fungi than after each fungus introduced separately.
W pracy przedstawiono sposób pomiaru aktywności cezu i potasu-40 w próbach środowiskowych za pomocą spektrometru gamma Tristan-1024 polegający na uwzględnieniu wpływu efektu Comptona na kształt obserwowanego widma, a następnie policzeniu impulsów w odpowiednich przedziałach energetycznych. Wykonane pomiary wykazały, że możliwe jest szybkie zmierzenie aktywności K-40 powyżej 30 Bg/kg oraz aktywności izotopów cezu Cs-137 i Cs-134 rzędu kilku Bq/kg w tzw. „świeżej" próbie bez konieczności stosowania kosztownej preparatyki