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The variations in average annual surface air temperature, precipitation, and runoff in the Selenga River basin (within Russia) are analyzed. It is demonstrated that the considerable increase in average annual temperature of surface air layers occurred in the 1980s-1990s. The decrease in peak water discharge in the rivers and the increase in the frequency of low-water periods were revealed in the forest-steppe and steppe zones of the Selenga River basin in 2001-2010. In the southwestern mountain regions (the Dzhida River basin) the river runoff increased during that period. 相似文献
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Averaged many-year measurement data on the concentrations of mineral forms of biogenic elements are analyzed, and their total concentrations in the rivers of Selenga, Chikoi, Khilok, Uda, Dzhida, and Temnik are evaluated. The monthly variations of the concentrations of major biogenic substances are characterized, and their ratios within a year are determined. Characteristics of river water runoff and biogenic substance concentrations are used to evaluate their within-year discharge by rivers. Characteristic variations in the ratios between the total and mineral forms of biogenic elements discharged by rivers have been revealed. It is established that the share of mineral components in the total input into the Selenga delta Ntot and Ptot are 82 and 22%, respectively. 相似文献
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In order to estimate the present-day pollution levels in the ecosystem of the Selenga River Delta and to monitor the changes caused by the discharge of household refuse and industrial wastes,as well as the functioning of the agricultural and stock farming,a comprehensive study of the water and bottom sediments in the main branches of the Selenga River Delta was carried out.This study has determined the concentrations of heavy metals in river water and bottom sediments in its delta. 相似文献
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Khazheeva Z. I. Urbazaeva S. D. Bodoev N. V. Radnaeva L. D. Kalinin Yu. O. 《Water Resources》2004,31(1):64-67
The overall concentration of Cu, Pb, Zn, Cr, Mn, and Fe are determined in the water and bottom sediments of the Selenga River delta. The concentration of Cu, Pb, and Zn is found to decrease in the lower course of the river, at the delta outlet. The concentration of Mn and Fe is found to decrease in the downstream direction from the river's upper course along the investigated delta arms, whereas the concentration of Zn and Cr in certain arms exceeds their concentration in the upper section of the delta. 相似文献
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The paper reports newly obtained data on the granulometric and mineralogical composition of bottom deposits in branches in the Selenga River delta and on the distribution of metals in various granulometric fractions and along the length of an branch of the river in the delta. It was determined that carbonates precipitate as a solid phases in the Kharauz branch, the most copious stream in the delta, and the metals are concentrated in the sand fraction. The bottom deposits of the minor Kolpinnaya branch are characterized by the accumulation of Mn oxides of variable composition, a mixture of colloidal or poorly crystalline minerals (most commonly, pyrolusite). Most of the metals are concentrated in the pelite fraction. 相似文献
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Seasonal and spatial dynamics of the concentrations of major ions, biogenic elements, organic matter, and microelements in Gusinoe Lake water are studied. The economic activity on lake coast has caused an increase in the concentrations of sulfate, sodium, and biogenic and organic matter in areas subject to direct technogenic impact. Lake areas subject to different technogenic impacts were found to differ in water mineralization and pH and the concentrations of microelements. The concentrations of Mo and Sr in lake water are 12–14 and 2–4 times greater than Russian MACs for water bodies used for fishery, respectively. 相似文献
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A water management assessment for the Selenga basin is made. The territorial-sectoral utilization of water for separate areas of the basin is considered. The influence of discharged waste waters on the river runoff is demonstrated. 相似文献
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The intra-annual and spatial dynamics of the major ion concentrations and TDS of Selenga River water (Russian segment) was analyzed. Water salinity was found to decrease in the open-channel period and in the downstream direction. The anthropogenic effect manifests itself not only in an increase in the concentration of reactive components with growing volume of discharged wastewaters, but also in changes in its annual distribution. 相似文献
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The gas regime and active reaction of water in Selenga basin rivers are analyzed. It is shown that, in the lower reaches of the Selenga and Uda rivers, which experience the highest anthropogenic impact, the minimal values of hydrogen index were recorded in under-ice period, while in the rivers of Chikoi, Khilok, Dzhida, and Temnik, during spring flood and summer freshets. The concentrations of organic substances are heterogeneous and vary widely under the effect of matter input with major tributaries and wastewater discharge from GOS. It has been established that the concentrations of readily oxidizable organic substances in 28–33% of the taken samples are above the established standards on maximal allowable concentrations in the period of open river channels. In spring and autumn, the organic matter in the rivers of the basin is mostly represented by soil terrigenous material. 相似文献
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