Water consumption from Russia's southern rivers has increased substantially in recent years as a consequence of intensified economic activity. The volume of irreversible river‐flow withdrawal from the Azov Sea basin varies between 11 and 13 km3 year−1. The majority of the abstracted water is used for irrigation. By 1990, the decrease in discharge into the Caspian Sea was 41 km3 year−1. Withdrawals of water from the Kura, Terek, Ural and other rivers have so far exceeded the ecologically admissible limits and become critical. The paper discusses methodological approaches for the elaboration of standards for water withdrawal and ecologically safe discharges into the southern seas. New data are presented on the dynamics of fish abundance as a function of the hydrological characteristics of rivers and water salinity. The results of the system analysis and regressive modelling formed the basis of a programme to develop policies for water management for fisheries in the lower Don. The principles and criteria for water withdrawal under variable hydrological regimes for the rivers entering the Azov and the Caspian Seas should be tested for their applicability for other water bodies (e.g. rivers, water reservoirs and lakes).

Flow regulation by large dams has transformed the freshwater and floodplain ecosystems of the Middle Amur River basin in Northeast Asia, and negatively impacted the biodiversity and fisheries. This study aimed to develop environmental flow recommendations for the Zeya and Bureya rivers based on past flow rate records. The recommended floodplain inundation by environmental flow releases from the Zeya reservoir are currently impracticable due to technical reasons. Therefore, the importance of preserving the free-flowing tributaries of the Zeya River increases. Future technical improvements for implementing environmental flow releases at the Zeya dam would improve dam management regulation during large floods. The recommendations developed for environmental flow releases from reservoirs on the Bureya River should help to preserve the important Ramsar wetlands which provide habitats for endangered bird species while avoiding flooding of settlements. The results emphasize the importance of considering environmental flow during the early stages of dam planning and the need to enhance the role of environmental flow in water management planning.

Translated from Gidrotekhnicheskoe Stroitel 'stvo, No. 12, December 2009, pp. 28 -32. Food provision and rationing of the supply are basic factors when preserving a variety of fish species and their populations in a water body.In conformity with effective nature-conserving legislation of the Russian Federation where farming activity is conducted in water entities of piscicultural value, including the operation of hydroelectric power plants, measures should be specified for the preservation of the water entities, biological water resources, and the water regime, and measures should be taken to preserve the habitats of the animal world, and conditions for their reproduction, feeding, and migration paths.Based on the Water Code of the Russian Federation [1] and the Status [2], water resources are utilized in accordance with the Rules of reservoir usage [1]. Organizations operating water-power and water-development works are obliged to ensure filling and drawdown regimes of reservoirs, observing piscicultural demands in sections assuming significance for the preservation and reproduction of fish resources.The Rules for utilization for the water resources of a reservoir represent the principal document on which management of the water regime of a reservoir is based. Dispatcher schedules for structure operation as a function of the water reserve in the reservoir at the time that a decision is made are developed as a component part of these Rules. The punctuality of decision making from several days to one month will depend on irregularity of the water influx to the reservoir, and on the requirements of water consumers as to the operating regime of the structures. A characteristic of water-level dynamics in a reservoirthe rate at which the horizon rises or falls in a specified time interval -is not stipulated on despatchers' schedules. This characteristic assumes critical, frequently determining significance, for both the safety of the water-development works, and also for pisciculture in the reservoirs. Such a position results in noncorrespondence with, and occasionally in contradiction to the reservoir's water-or power-supply demands in a zone of the despatcher's schedule on the one hand, and with respect to the rate at which the reservoir must drawndown to provide this supply on the other. This situation is characteristic when the interests of pisciculture are considered in the requirements for the reservoir's operating regime.In this paper, one approach to development of a regime for the filling and drawdown of reservoirs with consideration of piscicultural requirements is analyzed using the Kovda series of reservoirs as an example.The reservoirs in the Kovda series are referred to as lacustrine reservoirs, and are large water bodies with an overall surface area of 2, 800 km2 at the normal backwater level. These reservoirs are component parts of the White Sea Basin (Kandalaksha Gulf), and are located in the territory of Karelia and the Murmansk Oblast (Fig. 1).The water resources of the Kovda River Basin are util...

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