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1.
The soils formed on fortifications around the sites of ancient settlements 1500 and 2700 years old were studied in the Endyr archaeological landmarks (West Siberia, central taiga). It was shown that podzolic soils with morphological characteristics identical to those of the background soils were formed during these time periods. An attempt was made to estimate the characteristic times for some chemical characters. The greatest values of this parameter were about 8000 years. 相似文献
2.
A. M. Rusanov 《Russian Journal of Ecology》2003,34(1):10-15
Changes in the properties and ecological functions of soils under the effect of farming are considered. Evidence is provided that optimization of the structure of land inventory with regard to environmental conditions in a concrete region is a promising approach to the conservation and restoration of disturbed and degraded soils. A classification of soils with respect to their arability is proposed as a theoretical basis for reorganizing agricultural land use. 相似文献
3.
In case of an accidental release of radioactive substances into the environment, it is important to quickly and reliably estimate the radiation dose received by people in the affected area, and to determine the extent of the contamination. Measurements of the extent of the release and the subsequent contamination can be facilitated if there are predetermined reference sampling sites with known background radiation and inventory of radionuclides. Since 1996, 34 reference sites for soil sampling, field gamma, and intensimeter measurements have been established in western Sweden. Time series data for dose rates and radioisotope inventory have been collected at these sites, allowing for the investigation of changes in these parameters over time. The mass activity densities for the uranium and thorium series elements varied approximately between 10 and 50 Bq/kg and between 10 and 40 Bq/kg, respectively. The mass activity density of 40K was approximately in the range 300–800 Bq/kg. The radiation exposure due to 137Cs was rather small in this area. The dose rates calculated from in situ measurement data showed that the contribution to the total dose rate was almost entirely due to naturally occurring radionuclides. The measured dose rate was about twice as high as the calculated rate, even after subtracting the contribution from cosmic radiation. This may be explained by the fact that intensimeters generally are calibrated to measure the quantity ambient dose equivalent, which should not underestimate the effective dose. 相似文献
4.
A. M. Rusanov 《Russian Journal of Ecology》2007,38(1):11-15
The influence of the Buzuluk Pine Forest on biodiversity of plants and soil properties in adjacent territories has been studied. The results show that in the immediate vicinity of the pine forest, under the influence of the relatively mild and humid mesoclimate, natural phytocenoses are dominated by mesophytic species. Biodiversity reaches a peak at a distance of 17–18 km from the forest, which is explained by the presence of both mesophytes and xerophytes in the same phytocenosis. The same zone is also characterized by the maximum diversity of soil properties and structural complexity of the soil cover. Grass communities on ordinary chernozems with a homogeneous soil cover, typical of the steppe zone, are formed at greater distances from the forest. 相似文献