We describe a new measuring complex aimed at the investigation of small-scale processes in the upper active layer of the sea. The necessity of creation of a complex of this sort is justified and a circle of problems that can be solved with the help of this complex is described. The scales of resolution of horizontal and vertical inhomogeneities in measuring in the mode of vertical probing are theoretically estimated. The basic technical characteristics of the complex are presented. We also present the results of laboratory and field tests, which confirm the agreement between the calculated and actual technical possibilities of the complex. The structural features of various versions of the "Sigma-1" measuring complex (the "Sigma-1P" point-to-point-operation version and the "Sigma-1Z" probing version) are described.

We present a semiempirical model of the bottom turbulent boundary layer aimed at the application as one of the components of the procedure of evaluation of the vertical distribution of the concentration of suspensions in the coastal region of the sea. The model is based on data of laboratory experiments and is suitable for the sand bottom in a broad range of amplitudes of the bottom velocities of the wave origin.The processes of accumulation of sediments run for millions of years. To a significant extent, they formed the current shape of Earth's surface and, hence, deserve a detailed description, as exact as possible. The kinetic approach to the description of motion of suspensions is based on the use of certain ideas concerning the detailed structure of the analyzed processes. Thus, it is necessary to consider the probability distribution functions of solid and liquid particles and analyze the frequency and space spectra of the wave and turbulent motions. The kinetic models are more complicated than the hydrodynamic models but enable one to better understand the physical nature of the phenomena.For many years, the problems of physical modeling of various characteristics of the field of suspensions in the coastal region of the sea are studied at the Marine Hydrophysical Institute of the Ukrainian Academy of Sciences on the basis of the kinetic ideas [1]. The developed model combines the constructed probability distribution functions of suspended particles, the kinetic model of the intensity of wind-induced waves, and the spectral model of the subsurface turbulence generated by waves.As one of the main problems, we can mention the investigation of regularities of the transport of sand sediments under the action of waves in the surf zone. In passing to the shallow-water region, the long-wave part of the packet of wind waves is subjected to rapid transformations, and the pulsed horizontal wave motions generate bottom turbulence directly near the bottom. Note that its characteristics strongly differ from the characteristics of the subsurface turbulence.The initial roiling of sediments occurs with direct participation of the bottom turbulence which, in fact, forms the field of suspension at a distance of several first centimeters from the bottom and, hence, plays the role of the most important component of the kinetic models of motion of the sediments. The bottom turbulence lies within the sphere of action of the theory of boundary layer near the solid wall but contains numerous elements which make the theoretical description of this phenomenon much more complicated. Among these elements, we can mention the pulsed character of motion and the diverse types of roughness of the bottom. In view of these circumstances, the problem of modeling of the bottom turbulence is, to a large extent, based on the empirical data and, in particular, on the results of laboratory experiments.

Представлена концептуальная модель возвратно-поступательных перемещений крупной взвеси по нормали к берегу при фронтальном направлении волн. Разработка модели осуществлялась на основе данных измерительного комплекса «Донная станция», полученных при размыве узкой части Бакальской косы во время экспедиции в конце августа-начале сентября 2010 г. Показано, что анизотропия волновой составляющей скорости течения приводит к зависимости интегрального переноса крупной придонной взвеси от частоты основной волны. Волны с периодами больше критического значения 2,6 с в прибойной зоне осуществляют размыв, при меньших периодах происходит аккумуляция. Соответствующая критическому периоду сила западного ветра составляет 4,7 м/с. Предлагается вариант использования разработанной модели применительно к ситуации на о. Коса Тузла. Ключевые слова: аппаратурный комплекс «Донная станция», прибойная зона, придонная турбулентность, размыв берегов.

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We present the results of measurements carried out with the help of the "Donnaya Stantsiya" complex of equipment in the coastal zone of the Crimean shelf near Evpatoriya and near the southeast end of the Kosa Tuzla Island. For the same intensity of winds in these regions, the intensities of waves and turbulence in the coastal zone near Evpatoriya are much higher and, hence, the fluxes of suspended sediments are more intense. The accumulated data are intended for the correction of the kinetic model used for the evaluation of the characteristics of the field of suspended sediments in the shallow-water areas.