Computer hydrodynamic model of the Lower Volga

The structure of a hydrodynamic model of the Lower Volga, which has been developed for solving water management problems, and some results of computer simulation of variations of water level at the reach from the Volgograd HPP to the Caspian Sea are considered. The conditions under which the one-dimensional hydrodynamic model, developed in Delft Hydraulic Laboratory of Technical University based on Saint-Venant equations, can be successfully applied in the Lower Volga are determined.     

Anthropogenic transformation of the aquatic ecosystem of the Lower Volga

Many-year (1981–2009) variations of hydrochemical and hydrobiological characteristics of the state of the aquatic environment in the Lower Volga are presented. The development and transformation of the structural organization of aquatic organism communities are considered against the background of a tendency toward the accumulation of key pollutants and the regional features of those processes are considered. The study has shown that the aquatic ecosystem of the Lower Volga functions with its ecological state disturbed because of the strengthening of ecological regress.     

Heavy Metals in Bottom Sediment in the Upper and Lower Volga

Heavy metal concentrations in bottom sediment in some reaches of the Upper (the Ivankovo Reservoir) and Lower Volga (from Volgograd to the mouth offshore area). The bottom sediment in the Ivankovo Reservoir are shown to be heavily polluted by Cu and Zn and to a lesser extent, by Co and Ni; heavy pollution with Ni and Cr and moderate pollution with Zn and Mn were recorded in the Lower Volga. Principal component procedure was used to assess bottom sediment pollution. The role of organic matter in the formation of the Ivankovo Reservoir bottom sediment pollution with heavy metals is shown to be moderate because of the weak correlation between heavy metal concentration and organic matter content of bottom sediment. The same is true for the Lower Volga because of low organic matter content of bottom sediment. The major role in the redox cycle of elements is shown to belong to Fe in the Ivankovo Reservoir and Mn in the Lower Volga.     

Studying seasonal dynamics of surface water pollution in Lower Volga Basin

The results of environmental monitoring of surface-water quality in the Lower Volga Basin are given. The results of regular observations are differentiated. Water pollution is assessed based on the criterion of seasonal occurrence of chemicals in water at gage sections classified by zonal principle. An integrated estimate demonstrates considerable variations within a year and an increase in the normal annual concentrations of some pollutants of both natural and anthropogenic origin.     

A detailed luminescence chronology of the Lower Volga loess-palaeosol sequence at Leninsk

We present a detailed luminescence chronology of the loess-palaeosol sequences in the Lower Volga region of Russia at the Leninsk site – an important palaeogeographic archive describing the climate and environmental conditions of regressive stages of the Caspian Sea. The chronology of these sediments has received very little attention compared to the under- and overlying marine deposits. The degree of bleaching was addressed by making use of the differential resetting rates of quartz and feldspar. Our results show that the quartz OSL and feldspar pIRIR_50,290 signals were sufficiently bleached before deposition and uncertainties in bleaching have a negligible impact on the reliability of the luminescence ages. The combined quartz OSL and K-feldspar pIRIR_50,290 chronology constrains the main stages of the Northern Caspian Lowland evolution during the Late Quaternary. During early MIS 5 (130–120 ka), the northern part of the Lower Volga was covered by a shallow brackish water estuary of the warm Late Khazarian Caspian Sea transgression. After ∼122 ka, the Volga incised the Northern Caspian Lowland surface following sea-level decrease and the start of subaerial conditions at Leninsk. Loess accumulation rate increased towards the end of MIS 5 and two palaeosols of presumably MIS 5с and MIS 5a age formed, exhibiting features evidencing a dry, cold climate, influenced by long seasonal flooding by the Volga River. Cryogenesis affecting the MIS 5a soil is a regional phenomenon and is dated to between ∼70 and 90 ka. The overlying thick Atelian loess unit formed during the cold periods of MIS 4 and MIS 3. Clear erosional features at the top of the Atelian loess are constrained by luminescence to ∼35 to ∼24 ka, allowing reconstruction of erosion of 150–200 cm of loess.     

Water-Management and Environmental Problems of the Lower Volga and Ways to Their Solution

The key water-management and environmental problems of the Lower Volga are considered. The items discussed include the characteristics of intake and utilization of water resources and wastewater discharges in Lower Volga Region from 1990 to 2013. The current state of the key participants of water management complex is analyzed. The quality of Lower Volga water and ecosystems is shown, and the problems of maintaining the biodiversity are discussed. The key regional programs pertaining to the rational use and protection of water resources, as well as the development of water-management complex are considered.     

Geophysical studies of sturgeon spawning grounds in the Lower Volga and recommendations for their remediation

The results of geophysical studies in the Lower Volga allowed the authors to reveal areas suitable for sturgeon reproduction, determine the level of sturgeon natural reproduction in different zone of the river, evaluate the productivity of spawning grounds, and give recommendations for their remediation.     

Comparative Analysis of Models of Thermoerosion-Induced Channel Deformations in Rivers of Permafrost Zone

Water Resources - Studies of erosion processes in river channels of the permafrost zone are reviewed. Mathematical models of thermal erosion and the deformations it induces are discussed in...     

Tasks and functions of a decision support system for water resources management in the Lower Volga

The Lower Volga is a Russian region, which has a unique natural resources and a territory which is the area of collision of the interests of different economic branches that use water resources. The economic development of the region requires effective water resources management in harmony with natural conditions and the operation of the Volga-Kama reservoir system. A reliable management tool is a computer decision support system for the Lower Volga. The problems to be solved with this system answer the current water problems of the region. Data on the programs under implementation and to be developed are given; water apportioning model is given; and the way of coordinated choice of management regime of the Volga-Kama reservoir system and water resources use in the Lower Volga is demonstrated.     

Water Consumption and Drainage in the Volga Basin

Data on water withdrawal and use in different economic branches in the Volga basin in 1970–2000 are analyzed. Time variations in the removed volumes of waste, mine, and drainage waters, as well as in their chemistry, are considered. Characteristics of water use in 2010 are forecasted based on predictions of the socioeconomic development of Russia and extrapolation of the tendencies established in the dynamics of the analyzed indices.     

Analysis of Long-Term Variations in the Volga Annual Runoff

The stability of sample estimates of statistical parameters was analyzed for segments of the initial time series of annual runoff volumes of the Volga River at Volgograd for 1881/1882–1994/1995. The segments of series considered in this study differ in the extent of anthropogenic impact on the runoff and the type of atmospheric circulation and correspond to characteristic periods in the Caspian Sea level variations. The conclusion is made that there are statistically significant variations in the annual runoff of the Volga, caused by both natural–climatic and anthropogenic variations in the hydrological cycle.     

Present-Day State of Zoobenthos in the Upper Volga Reservoirs

The state of zoobenthos in the Ivankovo, Uglich, Rybinsk, and Gor'kovskoe reservoirs in 1994–2000 is evaluated based on a number of characteristics. Wide seasonal and year-to-year variations are recorded in some characteristics. Groups of stations are distinguished based on a combination of characteristics and a combined index.     

Energy Characteristics of the Transient Flow Effect on Channel and Bank Deformations and the Formation of Flow Secondary Pollution from Bottom Sediments

The ratio of the energy of water release into the lower pool of a waterworks facility for the time of release to the energy generated by the long-wave component of the wave spectrum caused by the release is considered. The effect of long-wave components of the wave spectrum on the channel and shore deformations is evaluated. An empirical relationship is proposed to describe the dependence of flow velocity on the release characteristics. Analysis of exchange processes between the flow and bottom deposits along with the obtained relationships is used to assess possible pollutant release from bottom deposits into water.     

Channel morphodynamics and sediment budget of the Lower Ganga River using a hydrogeomorphological approach

The Ganga River is one of the largest river systems in the world that has built extensive alluvial plains in northern India. The stretch of the Lower Ganga River is vulnerable to siltation because of: (a) the naturally low slope in the alluvial stretch; (b) the confluence of several highly sediment-charged rivers such as the Ghaghra, Gandak, and Kosi; and (c) the reduction in non-monsoon flows because of upstream abstractions of both surface and groundwater. Additionally, the Farakka barrage has impacted the morphology of the Ganga River significantly, both upstream and downstream of the barrage. Large-scale siltation in several reaches has reduced the channel capacity, leading to catastrophic floods in this region even at low discharges. This work has utilized historical remote sensing data and UAV surveys to reconstruct channel morphodynamics and compute sediment volumes accumulated in the channel belt along the Lower Ganga River between Buxar and Farakka. The work was carried out by dividing the total length of the river into four continuous stretches: (a) Buxar–Gandhighat (GW1, 160 km); (b) Gandhighat–Hathidah (GW2, 106 km); (c) Hathidah–Azmabad (GW3, 182 km); and (d) Azmabad–Farakka (GW4, 132 km). We document that major ‘hotspots’ of siltation have developed in several reaches of the Lower Ganga during the last four to five decades. Sediment budgeting using planform maps provides estimates of ‘extractable’ volumes of sediment in GW1, GW2, GW3, and GW4 as 656 ± 48, 706 ± 52, 876 ± 71, and 200 ± 85 Mm³, respectively. These estimates are considerably lower than those computed from the hydrological approach using observed suspended sediment load data, which assumes uniform sedimentation between two stations. Further, our approach provides reach-scale hotspots of aggradation and estimates of extractable sediment volumes, and this can be very useful for river managers to develop a strategic sediment management plan for the given stretch of the Ganga River.     

Pollution of Volga Mouth Area

Water Resources - Estimates of pollution of Volga mouth area in 2016 are given. Data on the distribution of water flow into the Lower Volga and the results of state environmental monitoring were...     

Distribution and Activity of Bacteriobenthos in the Upper Volga Reservoirs

Regularities of bacteria distribution in the bottom sediments of the Upper Volga reservoirs are studied. Human-induced changes in the structure and activity of bacteriobenthos communities occurring in water body areas adjacent to towns and settlements are described. Reservoir zones subject to long-term human impact are distinguished.__________Translated from Vodnye Resursy, Vol. 32, No. 4, 2005, pp. 489–499.Original Russian Text Copyright © 2005 by Kosolapov, Krylova, Kopylov.     

Concentrations of Heavy Metals in the Upper Volga Bottom Deposits

The distribution of heavy metals in the Volga bottom deposits is studied. According to the degree of pollution with heavy metals, three stretches are singled out within the river reach under consideration. A drastic increase in Cu and Cd concentrations in bottom deposits is established. A close statistical correlation between Cu and Pb accumulation and the organic matter content of bottom deposits is revealed.     

Statistical Estimates of the Dependence of the Caspian Sea Level and the Volga Runoff on the Amount of Precipitation onto the Volga Watershed

Correlation between the Volga runoff, the Caspian Sea level increments (CSL), and the amount of precipitation is considered. The variables involved are averaged over seasons, periods, and the year. Variations in the obtained correlations within the 20th century are analyzed. A method is proposed for determining the optimal time interval, within which precipitation is to be taken into account in predicting the Volga runoff and CSL. Seasonal anomalies in the precipitation and annual Volga runoff are analyzed for low-water and high-water periods. Linear trends of seasonal sums of precipitation for the period from 1891 to 1998 and in individual parts of this period are evaluated.     

黄河下游南四湖地区黄河河道变迁的湖泊沉积响应

黄河下游地区湖泊演化多与黄河河道变迁密切相关,进行高分辨率的湖泊沉积环境的研究,可揭示历史时期黄河下游的河道变迁,本文以南四湖ＤＳ孔为例,探讨河道变迁的湖泊沉响应。     

Sedimentation in variable-backwater zones of Volga chain reservoirs

The direction and rate of sedimentation processes in variable-backwater zones—upstream river-type reaches (lower pools of hydropower systems) and large bays of reservoirs of the Volga chain (many-year aspect, mesoscale level) and in the deltas of median and small rivers in the Upper Volga region, regulated by beaver ponds (seasonal aspect, microscale level) are characterized. The changes in bed relief and the structure of sediments in the examined zones were found to have common features and pass all stage of bed and shore formation typical of lowland reservoirs-from active erosion-abrasion activity to its gradual decline and from intense to passive sedimentation.