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991.
G. V. Vorobyev A. Yu. Alyabyev T. I. Ogorodnikova A. F. Khamidullin V. N. Vorobyev 《Russian Journal of Ecology》2014,45(2):90-94
Microcalorimetric, gasometric, and nuclear magnetic resonance (NMR) methods have been used to evaluate heat production, gas exchange, and root membrane permeability in dandelion of different morphological forms from populations exposed to different levels of air pollution. The results show that these forms differ in the level of energy metabolism and that the form with a higher metabolic level (T. off. f. dahlstedtii) is more tolerant of air pollution with motor vehicle exhausts. 相似文献
992.
Ecological and biological characteristics of Cyclachaena xanthiifolia (Nutt.) Fresen., have been studied in four regions of the Southern Urals and Cisural region. Communities including this species have been attributed to association Ivetum xanthiifoliae Fija?kowski 1967 of the class Stellarietea mediae R.Tx., Lohmeyer et Preising 1950. It has been shown that ecological habitat conditions have a significant effect on the majority of morphometric parameters of C. xanthiifolia, accounting for 1.3 to 51.4% of their total variance. Seed production averages 6500 seeds per plant. Extensive dispersal of the species over the Southern Ural region is predicted. 相似文献
993.
Studies in the vicinities of copper smelters and in undisturbed areas of the Middle Urals have been performed to evaluate the effect of industrial pollution with heavy metals on macro- and micromorphological parameters of kidneys (weight, weight index, the spectrum and frequency of histopathologies) in the bank vole (Clethrionomys glareolus Schreber, 1780) and on the accumulation of Cu, Zn, Cd, and Pb in this organ. It has been found that the kidneys of voles from polluted areas accumulate considerable amounts of heavy metals, with their concentrations increasing with age and/or sexual maturation. The kidney weight, index, and the frequency and severity of the majority of observed nephropathies also increase upon change in the reproductive-age status of animals. These parameters show no dependence on the degree of industrial pollution: at individual level, none of the heavy metals accumulated in the kidneys has produced any effect on the frequency and severity of nephropathies. These results contradict the prevailing opinion that toxicants play the determinant role in the development of nephropathies in small mammals inhabiting polluted areas. Therefore, the causes of nephropathies should be sought among other factors, not related to pollution. 相似文献
994.
The structure of bumblebee communities has been studied in some ecosystems of Kunashir Island and Southern Sakhalin. The island taxocenes include five to eight bumblebee species. Bombus hypnorum is dominant in the majority of habitats. In geothermal areas near hot springs on Kunashir, the families of this species develop more rapidly than in areas without geothermal heating. 相似文献
995.
A. M. Rusanov 《Russian Journal of Ecology》2014,45(4):243-248
The results are presented that have been obtained in studies on changes in the species composition, geobotanical characteristics, and productivity of natural vegetation in arid steppes of the Cisural region during the past few decades (1977–2012). Consideration is given to the significance of the soil factor in the processes of transformation of zonal vegetation. The increasing role of arid steppes as a natural barrier to desertification is demonstrated. 相似文献
996.
Intrapopulation diversity and correlations of 30 volatile compounds in needles have been studied in Scots pine populations of southern Siberia. Significant differences between populations have been revealed in the correlation pattern of relative terpenoid contents in needle samples. Stable combinations of closely associated mono- and sesquiterpenes and specific features of the general pattern of correlations between relevant characters have been determined. 相似文献
997.
998.
Changes in the distribution and abundance of some game mammals have been analyzed over the past 100–150 years. Correlations between changes in the population density of species in slightly and strongly transformed habitats have been revealed, which show that the influence of anthropogenic factors on the population density of species has a highly complex pattern. Transformation of habitats leads to disturbances in the species composition of communities, changes in the population density of species, and disruption of functional relationships between them. 相似文献
999.
The aim of research was to assess the changes of annual radial increment of Scots pine forests in the vicinity of intensive and moderate industrial pollution of “Achema” factory producing mineral fertilizers. Our results indicate that the radial growth of the pine tree can be divided into three different periods: growth promotion, growth inhibition and growth recovery. Low levels of nitrogen emissions were beneficial for tree growth: the radial increment in the intensive and moderate pollution zones increased by 15–25% and 10%, respectively compared to control. During the growth inhibition period, the total annual industrial emission was 37–40 kt, and 40–45% radial growth loss was observed for the closest and 15–20% for the most distant stands. The radial growth decrease slowed down and the recovery of damaged stands began in 1990–1992 then air pollution was considerably reduced. The rate of forest recovery was high for the most damaged stands: their radial growth was close to control in 2000–2011. 相似文献
1000.
J. Cambrollé S. Redondo-Gómez E. Mateos-Naranjo T. Luque M. E. Figueroa 《Russian Journal of Ecology》2014,45(3):215-222
Glaucium flavum Crantz. is a short-lived perennial herb distributed in coastal zones from the Black Sea to southern, western and north-western Europe. Despite its diminishing area of distribution and potential pharmacological value, little is known about the ecophysiological features of this coastal species. We investigated the photosynthetic performance of G. flavum by measuring gas exchange, chlorophyll fluorescence, photosynthetic pigment concentration and leaf water content over the space of a year in a coastal habitat of SW Spain. We also measured the variation in total concentrations of nitrogen, phosphorus, sulphur, potassium, calcium and magnesium, in the leaves and soil, throughout the study period. G. flavum showed a high resistance to summer drought conditions which appeared to be due to the high degree of stomatal control. The potential photochemical efficiency of photosystem II showed minimum values during the winter, indicating that low temperatures can produce negative effects within the photosynthetic apparatus. However, the marked decline in net photosynthesis during the winter seems to be mainly related to a loss of metabolic activity. Although leaf nutrient concentrations were, in general, within the normal ranges, phosphorus availability seems to be limited by the high calcium concentrations detected in the soil of the study site. Our study points out the efficiency of the different physiological adaptations of this rare and endangered coastal species in coping with the strong seasonal variability of the Mediterranean climate. 相似文献