Vol 46, No 2 (2019)

The space and time distribution of reservoirs over the drainage basins of Arctic seas within Russian Federation territory and the main rivers flowing into the Arctic Ocean is analyzed. The Ob River is considered along with the Kazakh part of the Irtysh Basin. The stages of the hydroengineering development of water resources are identified and characterized. The effect of reservoirs on the water regime and the annual runoff of major rivers is determined. The perspectives of the construction of reservoirs are demonstrated.

Bankfull discharge is highly correlated with bankfull elevation. The main channels and bankfull elevations in multi-thread sections are ambiguous and need additional indicators to define. Thus, two additional indicators (maximum width and effective width coefficient) were adopted to estimate the bankfull elevation of both multi- and single-thread cross-sections. Three geometric-criterion based definitions of bankfull elevation (minimum width-depth ratio, abruptly changing-point of wetted area to top channel width ratio, first maximum Riley bench index) were selected to estimate bankfull elevation. Typical cross-sections selected were the Huayuankou and Lijin cross-sections in the Lower Yellow River. More than 300 cross-sectional datasets of the Huayuankou and Lijin were collected to calibrate the value of effective width coefficient. Second, calibrated coefficients were verified by various applications, estimating the variation of sectional bankfull discharge in floods, estimating the variation of sectional bankfull discharge along a river reach, and estimating annual variation of reach-scale bankfull discharge. Third, sensitivities of physical parameters were further analyzed. Calculation and analysis showed that the effective width coefficient was necessary for estimating bankfull elevation in multi-thread cross-sections, and these three definitions could be adapted to estimate the bankfull elevation when coupled with these two indicators. Besides, the key point of this method was defining the maximum width and effective width coefficients, as other factors have limited effects on estimating bankfull discharge. Analyses can also provide information for field survey refering to the balance between time consuming and detailed measurements.

A brief review is given for the most significant results obtained in studies carried out in the Institute of Mechanics, Moscow State University, and focused on a new class of transient flows of an incompressible liquid that form when vertical plunging or free flat or axially symmetrical water jets penetrate through the surface of water placed in relatively narrow channels or when free thin-wall water jet, flowing from a conical slotted nozzle with a vertical axis penetrates through water surface in a rectangular vessel. Wide ranges of the values of key parameters were found to exist at which self-oscillation flow regimes unknown before form in the liquid. Different formation mechanisms of such regimes and the characteristic features of the experimentally and numerically determined dependencies of self-oscillation periods on the key parameters are discribed. Possible applications of the obtained results are given.

Water quality dynamics along the Northern Dvina River is analyzed under the conditions of anthropogenic impact. Overall, river water is classified as very polluted. The cases of high and extremely high pollution are considered for different river reaches. The most widespread pollutants are organic matter and compounds of iron, copper, and zinc. The long-term average annual volumes of the inflow of individual pollutants along the river are 2–5 times the MAC. In addition, a tendency toward some improvement of river water quality downstream the river was identified with a decrease in oil products and zinc compounds.

The average concentrations of elements Fe, Mn, Zn, Pb, Cu, Cr, V, Co, Cd, Ni, As, and Mo in the subcolloidal fraction of bottom sediments were determined in the northern and central parts of the Amur Bay. The concentrations of metals Pb, Co, Ni, Zn, Cr, V, and As in bottom sediments subject to direct influence of the Razdol’naya River were shown to increase by 5–17% because of their sorption on Fe and Mn oxy hydroxides. The concentrations of some elements (As, Cu, and Mo) in the bottom sediments of the bay were found to be 21–55% above their average concentrations because of their accumulation by humic substances.

Сomposition of chemical elements in natural waters and rocks of the Albynskoe Gold Field have been studied to elusidate the possible environmental effects of open cast mining. The ore has been found to contain a group of environmentally hazardous elements, which, either because of a considerable concentration in the ore (As, Sb, Mo, W), or because of the high toxicity class (Cd, Be, U) can cause a considerable geochemical load onto the regional ecogeosystem. The natural watercourses in the zone of influence of the field show an excess of the MPC for water bodies used for fishery (MPC_fish) in terms of Мо, W, As, as well as high concentrations of Sb and U; the overwhelming majority of the microelements show concentrations below the respective MPC_fish or below their detection limits. The analysis of the results of laboratory experiments, simulating the processes of biochemical weathering of ore material by various natural agents, showed that toxic and extremely toxic elements can be leached and dispersed in the zone of influence of deposit development.

The characteristics of cardioactivity and the accumulation of metals in the tissues of bivalve mollusks from different water areas of the eastern Gulf of Finland and Rybinsk Reservoirs have been considered. The functional state of the mollusks has been analyzed with the use of original hyperosmotic test impact. An approach is proposed to ranking the quality of freshwater ecosystems by the state of bivalve mollusks dwelling in them.

The notion of diffuse pollution process in water bodies of different dimensions is formulated. An algorithm is given for calculating the average annual volume of the export of major biogenic elements—nitrogen and phosphorus—from the watershed into ravine and river network of a small river. The article also gives the results of a series of computer simulations of the characteristics of spring overland runoff, soil erosion, and the export of biogenic elements from the watershed into the river network of the Istra R. under hypothetic changes in its landscape structure under the effect of urbanization and reforestation activities.

This paper aims to present water resources management problems in Serbia and recommend possible solutions. Key issues involve water quality and water quantity. Water quality is endangered by organic pollution from different sources and low degree of waste water treatment. Incomplete exploration of water resources availability as well as their inadequate exploitation are the biggest problems related to water quantity. Other problems involve lack of harmonized legislation, insufficient investments in water resources management, inadequate water price, low level of services, the lack of an effective integral water management system, illegal construction in the areas of water sources and potentially floodplains as well as lack of monitoring. In order to deal with these problems and overcome or mitigate their consequences, complex of measures should be implemented in the frame of interdisciplinary and transdisciplinary national and international projects.

The lack of water resources as a critical substance and the increase of water demands and also the complexity of water resources management issues are made the integrated water resource management as an essential tool. In this study considering different water demands, planning and policy analysis in the Sistan region, with the water evaluation and planning system (WEAP) and applying the sub-model of irrigation demands of the FAO crop requirements approach is used. Water planning and policies are defined and simulated with 15 scenarios from 2015 to 2030. Based on the results, Implementation of policies such as the increasing of irrigation efficiency in the agricultural consumption had a positive effect on the saving of the water resources and the water scarcity reduces. Also due to the priority of supplying drinking water in all scenarios, no unmet demand is observed in this part of consumption. Moreover when the industrial demand is joined to the consumptions as a stakeholder, the amount of less water is released for the agricultural and wetlands demands. Therefore, it is recommended that different scenarios be implemented such as increasing of the irrigation efficiency, reducing of the cultivation area and reducing the domestic water consumption.