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The paper considers the characteristics of the gametes, habitats and spawning conditions of sturgeon, which are important for improving the biotechnology of their artificial reproduction. Based on the native data and literature, there have been analyzed the limits of variation of micropyle of ship sturgeon (Acipenser nudiventris Lovetsky, 1828) and some other species, as well as the features of the micropylar complex. The material for the study conducted in 2018-2019 served the ovulated eggs and caviar from the broodstock of the second-third generation of ship sturgeon, which contained in the conditions of the State Regional Centre for Sturgeon Gene Pool Conservation “Kubanbioresursi”. Ship sturgeon has been found to have the largest average number of micropyles among low-chromosomal species. In the main sample, the number of micropyles varied from 2 to 41, with an average value of 11.09 ± 0.24 and a concentration of indicators from 2 to 19 (94%). The location peculiarity and a slight variation in the number of micropyles in one female species of ship sturgeon have been revealed, as well as the different shape of a micropylar complex, as opposed to the similar shapes in other sturgeon species: ship sturgeon has not the funnel-shaped micropylar complex, but the bowl-shaped one. The ship sturgeon spawns under conditions of high water speed and a micropylar bowl, the diameter of which exceeds 2-3 times the diameter of the funnel and increases the collection area of the highly diluted seminal fluid. From a practical point of view, studying these features is important for improving the biotechnology of artificial insemination of roe of rare species in conditions of almost complete absence of natural reproduction in natural conditions.

The article presents the analysis of the research literature on biology, ecology, artificial and natural reproduction, behavior, nutrition and taxonomic status of ship sturgeon (Acipenser nudiventris Lovetsky, 1828) over the period 1877-2020. There are given the private data obtained during interviews with fishermen, which was published earlier. The approaches to ship artificial reproduction have been analyzed; the corresponding data from the Russian research literature and from the foreign sources are presented.Ship sturgeon is one of the most vulnerable and small in number sturgeon species in the world, the individuals of which are still found in the Balkhash-Ili basin (Kazakhstan-China) due to its invasion in 1933-1934. It should be mentioned that this is the only example of successful acclimatization of sturgeon. Ship sturgeons have the following ecological and biological characteristics: prolonged living in the mountain rivers with downstream migration into the delta and the sea coast; high rates of fertility coupled with high mortality rates in early ontogeny; a diverse diet depending on the habitat. Artificial reproduction of ship sturgeon was started in 1941 in Azerbaijani SSR. Unfortunately, the species did not receive a proper attention because of its scarcity in the natural habitat, which resulted in their complete disappearance. Today the conservation of ship species requires taking the urgent measures: forming ship broodstock, introducing it into aquaculture, clarification of reproductive biotechnology, studying the peculiarities of ship growth and maturation in the fish farms.

The article provides a classification list of a large number of heuristic techniques for solving various problems of designing a class of hydraulic structures, taking into account the conditions of functional operation of soft floating structures (MNCs) as water intake structures. The concept of rational use of surface water resources provides for an ecosystem approach that allows us to consider a water body together with the catchment area of the hydrographic river network, the surface layers of the atmosphere above it, measures taken to select the calculated water flow rate (Q m3/s), taking into account the consideration of environmental safety in the zones of influence of water intake - as a single system in as a whole. Providing EC in VTK puts forward a number of main tasks to improve existing structural and technological devices and create new ones using modern domestic materials, for example, high-strength synthetic fabric materials. When creating environmentally acceptable design solutions to provide EC in the zones of influence of VTK, one of the most promising areas at present is the methodological basis for the synthesis of soft-coated structures in the composition of VTK. The reliable functioning of both a separate structural element and the structure as a whole should be conditioned by the possibility of periodic updating of its constituent structural elements.