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981.
982.
Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses.  相似文献   
983.
Changes in the main climatic factors (air temperature and total precipitation) and their effect on the radial increment of Scots pine (Pinus sylvestris L.) over the period from 1933 to 2002 were studied in an insular pine forest growing in the steppe zone of the Southern Urals. Evidence for a significant increase in the amount of precipitation and air temperature in the second half of this period was obtained. Functions of response of radial increment indices to climatic parameters were analyzed. Relative contributions of air temperature and precipitation to variation in the radial increment of pine in different time intervals proved to differ in relation to climate changes during the past century.  相似文献   
984.
The widespread public belief that during the bombardment of Vojvodina (Yugoslavia) this region was contaminated by depleted uranium has recently raised public concern with respect to the potential contamination of agricultural products due to soil radioactivity. Based on the gamma-spectrometric analysis of 50 soil samples taken from the region of Vojvodina we concluded that there is no increase of radioactivity that could endanger the food production. Taking into account the transfer factors of 137Cs to plants, the measured activity concentrations of this isotope should not endanger the health safety of the produced food. No traces of depleted uranium have been found. The natural radioactivity levels are compared with the results form other countries.  相似文献   
985.
There is a continual supply of new experimental data that are relevant to the assessment of the potential impacts of nuclear fuel waste disposal. In the biosphere, the traditional assessment models are data intensive, and values are needed for several thousand parameters. This is augmented further when measures of central tendency, statistical dispersion, correlations and truncations are required for each parameter to allow probabilistic risk assessment. Recent reviews proposed values for 10-15 key element-specific parameters relevant to (36)Cl, (129)I, (222)Rn, (226)Ra, (237)Np and (238)U, and some highlights from this data update are summarized here. Several parameters for Np are revised downward by more than 10-fold, as is the fish/water concentration ratio for U. Soil solid/liquid partition coefficients, Kd, are revised downward by 10-770-fold for Ra. Specific parameters are discussed in detail, including degassing of I from soil; sorption of Cl in soil; categorization of plant/soil concentration ratios for U, Ra and Np; Rn transfer from soil to indoor air; Rn degassing from surface water; and the Ca dependence of Ra transfers.  相似文献   
986.
987.
A comparative analysis of reproductive behavior has been performed in the steppe lemming (Lagurus lagurus) and narrow-skulled vole (Microtus gregalis). The results show that the species are similar in certain behavioral features indicative of the stability of mating pairs. However, in the narrow-skulled vole, unlike in the steppe lemming, mature males in olfactory tests show preference for receptive sibling females versus non-kin females. Probably, it is the absence of the incest taboo that allows the involvement of young of the year in reproduction within growing family groups and accounts for “coloniality” of the species.  相似文献   
988.
The luminescence of quartz extracted from recently fired building material is known to detect doses of few mGy and can be successfully employed in the case of large scale radiation exposures due to nuclear accidents or terrorist acts. One brick and two tiles (50-80 years range) collected from an urban settlement were used to test the realistic minimum detectable dose limits of retrospective luminescence dosimetry. Independent methods like alpha counting, beta dosimetry, gamma spectrometry and flame photometry were used for the annual dose assessment. Two approaches were employed for the evaluation of the total accrued dose: regenerative dose and additive dose. The former allows the assessment of doses due to anthropogenic sources of radiation as low as approximately 12 mGy by using 10-year-old samples, but it can be applied only in samples showing no sensitisation. The latter can be applied to any sample, however, the related uncertainty is higher and minimum detectable anthropogenic dose in young samples amounts to 20 mGy.  相似文献   
989.
A comparative analysis of epigenetic variation has been performed in nine European populations and population groups of the American mink. It has been shown that differentiation of samples in nonmetric characters is due mainly to endogenous processes that have occurred in introduced populations in the course of colonization of new territory by the invasive species. Environmental factors have played a secondary role, with the influence of the geographic (latitudinal) origin of a given sample being considerable and stronger than that of macroclimatic factors.  相似文献   
990.
Russian Journal of Ecology - Natural recovery of forest ecosystems after the termination of impacts caused by emissions from large industrial enterprises gives a clue to their sustainability...  相似文献   
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