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831.
The results of radiometric and haematological studies of striped field mice (Apodemus agrarius) sampled over the years 1995-2003 from the territory of the preserved radioactive waste burial (RWB), which is located in the Moscow recreation forest "Kuzminki", are presented and discussed in the paper. It was shown that the level of 90Sr-90Y content in mice sampled from the RWB area varies within the range of 0-1200 Bq/kg with an average of 98.7+/-21.5 Bq/kg. The content of 90Sr-90Y in the body of 80% of the mice sampled from the RWB area was below 100 Bq/kg. Only in 4% of the sampled mice, the 90Sr-90Y specific radioactivity was above 300 Bq/kg. Haematological indications of the animals sampled from the RWB area were within the range of normal physiological fluctuations. Nevertheless, a slight but statistically significant increase in the average amount of erythrocytes and the average percentage of banded neutrophils was registered in peripheral blood of the mice.  相似文献   
832.
The states of the populations of five dominant species of predatory mammals living in the area affected by the Kalinin Nuclear Power Plant (NPP) and in remote districts of Tver’ oblast have been compared. A total of 1120 skulls, including 708 skulls from the vicinity of the NPP, have been examined. The data on parameters characterizing similarities between the samples, the degree and structure of intrapopulation diversity, and ontogenetic stability suggest with a high probability that the Kalinin NPP has no effect on wild populations of predatory mammals.  相似文献   
833.
The results of studies on the radial increment of larch and pine in central Yakutia are presented. The application of dendroclimatological methods to the study of tree-ring chronologies has made it possible to evaluate tree growth response to the dynamics of climatic factors over the past 120 years. The results of analysis of radial tree increment show that the onset of the growing season has shifted to earlier dates by the end of the 20th century.  相似文献   
834.
The functional state of the indicator species, the Gray mussel Crenomytilus grayanus (Bivalvia), has been analyzed in five areas of Peter the Great Bay exposed to anthropogenic pollution. The following indices of the state of mussels have been used: molecular biomarkers of energy metabolism—Na+,K+-ATPase, Mg2+-ATPase, and total ATPase activity—as well as the level of lipid peroxidation (LPO) and glutathione concentration in the hepatopancreas, gills, and gonads of mussels. The activity of ATPases, LPO level, and glutathione concentration significantly change in mussels from polluted areas relative to those in mussels from a conventionally unpolluted area (a bay in the Far Eastern State Marine Reserve). The molecular biomarkers used in the study provide reliable information on animal metabolism in impact areas. With consideration of the data obtained, it is concluded that the state of mussels in polluted areas is impaired.  相似文献   
835.
836.
Five bivalve species--Mytilus galloprovinciallis (Mediterranean mussels), Venus gallina (stripped venus), Modiola barbatus L. (bearded horse mussels), Pecten jacobeus (scallops) and Callista chione (hard clams)--were collected from seven areas in Aegean Sea, Greece, between August 2001 and January 2003 and analyzed for organotins (OTs). The concentrations (as geometric means) found were 17.1 ng g-1 for tributyltin (TBT), 18.8 ng g-1 for dibutytltin (DBT), 7.8 ng g-1 for monobutyltin (MBT) and 13.0 ng g-1 for triphenyltin (TPhT) (wet weight), which are at similar or lower levels than those reported worldwide. Studying OTs distribution between different bivalve species, lower concentrations were observed in mediterranean mussels, possibly due to their growth in water column (grown on sea net pens in mussel farms), in contrast to the free-ranging species, collected from fishing grounds. Concentrations of the OTs in the examined bivalves varied seasonally.  相似文献   
837.
In summer 1993 we measured the transfer of (239/240)Pu to milk from herbage from a pasture located 5 km from the Chernobyl nuclear power plant. In one treatment cows were allowed to graze freely on the pasture. In a second treatment, cows were fed herbage collected from the pasture in stalls. The milk transfer coefficient; F(m) did not vary significantly between treatments and the mean value of 7.5x10(-6)d l(-1) was higher than previously reported values. Despite many values of F(m) for Pu in the literature we identified few relevant original data sets. Transfer coefficient values for Pu are only appropriate when used in conjunction with a specified time period or an appropriate model which allows for the biological half-life. We recommend for screening purposes an F(m) value of 1x10(-5)d l(-1) for Pu, with an order of magnitude lower value being appropriate for cows which are only exposed for one grazing season.  相似文献   
838.
Data on radionuclide transfer to domestic chickens and ducks obtained from research performed in the former Soviet Union were reviewed to provide transfer coefficient values (Ff) to poultry and edible egg contents. The majority of the data are from experiments with 90Sr and 137Cs, reflecting the importance of these radionuclides after global fallout and major radiation accidents. Data for 3H, 54Mn, 59Fe, 60Co, 22Na 65Zn, 131I and U are also given. The values derived have been compared with those in the current IAEA Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) and the recent revision which incorporates the values from this paper. The Russian-language data give improved estimates for many radionuclides and the revised handbook is now based on the better quality data given for chronic administration.  相似文献   
839.
The levels of total lipids, peroxidation products, and antioxidant activity in the liver were studied in fish species living in unequally polluted areas of the Rybinsk Reservoir and differing in their ecology and taxonomic position: the bream (Abramis brama L.), roach (Rutilus rutilus L.), burbot (Lota lota L.), and zander (Stizostedion lucioperca L.). The fish from polluted water areas were characterized by higher levels of total lipids and malonic dialdehyde and a deficiency of antioxidants. It is shown that the test parameters depend on the type of feeding and mode of life of the fish species.  相似文献   
840.
不同品种辣椒镉亚细胞分布和化学形态特征差异   总被引:3,自引:2,他引:3  
彭秋  李桃  徐卫红  焦璐琛  邓继宝 《环境科学》2019,40(7):3347-3354
前期试验对91个辣椒品种资源进行筛选,以高积Cd型品种(X55)、中积Cd型品种(27)和低积Cd型品种(17)各一份,采用盆栽试验研究不同镉水平(0、5和10 mg·kg-1Cd)下3个品种辣椒Cd转移和富集能力差异以及镉在果实中亚细胞分布和形态特征.结果表明,Cd胁迫下,辣椒地上部干重在种间表现为品种X55 17 27.果实Cd转移系数在同一Cd水平下均表现为品种17 27或X55.辣椒果实各亚细胞组分中Cd含量在种间表现为品种27 17 X55.辣椒根、茎、叶和果各亚细胞组分中Cd含量均表现为细胞壁(F1)细胞器(F2)细胞可溶性组分(F3),Cd被限制在细胞壁中,在辣椒Cd解毒机制和抗性中起重要作用. 3个品种辣椒果实各Cd化学形态含量随Cd处理水平的增加而增加,且大小均表现为CdNaClCdHAC CdR CdHCl CdW CdE.辣椒果实中的CdNaCl和CdHAC占比例较大可能是辣椒降低Cd生物毒性的一种防御机制.  相似文献   
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