Comparative analysis of muscle tissue amino acid composition of sturgeon breeded under natural and industrial conditions

The article presents comparative data on the chemical and amino acid analysis of the muscle tissue of sturgeons of the natural ichthyofauna of the Volgograd reservoir and those grown in a cage farm in the natural temperature regime of the 4th zone of fish farming in the Russian Federation using balanced feeding. The results obtained indicate the saturation of the muscle tissue of sturgeons consuming artificial feed with amino acids. The difference in nutrition is reflected in the biological value of meat. An important indicator of the biological value of a product is the qualitative and quantitative composition of muscle tissue amino acids. The natural nutrition of the Volgograd Reservoir does not fully satisfy the sturgeon’s need for protein nutrition. Industrial methods of cultivation make it possible to optimally organize biologically complete feeding of fish, which contributes to the maximum manifestation of their genetic potential and production of functional products.

Benthic invertebrate communities in the water areas of the Volgograd reservoir near the villages Akhmat and Zolotoye as one of the characterization of conditions for commercial fish reproduction in 2020

The main factor affecting the success of the reproduction of limnophilic fish is the level height and duration of the spring flood with uniform heating of the water. However, the efficiency of fish reproduction also depends on other factors, for example, on the development of the food supply for early juveniles. In 2020, in the water area of the Volgograd reservoir near the villages Akhmat and Zolotoye, according to the results of catches of fry net, developed very unfavorable conditions for the reproduction of commercial fish. The values of production indicators (net primary production and the rate of respiration of the plankton community) in 2020 turned out to be minimal. The dynamics of the abundance, and especially the biomass of benthic invertebrate communities, turned out to be very similar for both water areas in 2018 and very different in 2020. In terms of abundance, among benthic invertebrate communities, in the water area near the village Zolotoye in July 2020, was dominated by oligochaetes and chironomids, and oligochaetes in terms of biomass. At the station near the village Akhmat in July was dominated by chironomids in terms of numbers, and oligochaetes in terms of biomass. In August and September, both in terms of abundance and biomass, oligochaetes dominated in both water areas. There is a correlation between the state of production processes and the state of benthic invertebrate communities in the reservoir. However, the efficiency of fish reproduction correlates, first of all, with the level and temperature regimes of the reservoir during the spawning and feeding period. The decrease in the proportion of underyearlings of crucian carp and perch feeding on benthic invertebrate communities in the catch of fry net in 2020 may be due to both an unfavorable level regime and a drop in the feeding capacity of the water areas.

Introducing Nature-Saving Technologies as an Environmental Imperative in the Development of Regions

The article deals with the conservation and restoration of water resources, which is one of the basic factors of regional development. O.V. Inshakov paid attention to this factor highlighting natural resources (land, water, minerals, forests and others) with a certain set of indicators of quantity, structure and quality in the structural and logical model of the development of Volgograd region – 2030. One of the key directions of the civilization development in the 20th century was the search and practical application of a new class of technological and technical solutions in the field of water conservation with the ecological imperative “preserve nature for future generations”. This implies the gradual elimination of their practices of economic activity processes that can lead to irreversible consequences in the ecosystem of the planet. In this context, the issues raised in the article on the study and preservation of natural water quality in the South of Russia are very justified and relevant. As a result of the anthropogenic impact (pollution by industrial, agricultural and municipal effluents), nitrogen, phosphorus, chlorine-containing substances causing fatal mutations and the process of “blooming” of water bodies are concentrated in excess in natural water. Many countries face the problem of “blooming” of water bodies as a result of intensive growth of blue-green algae. The importance of solving this problem is explained by the fact that the toxins entering water from the biological activity of blue-green algae are very dangerous for human health and other organisms. Scientific literature provides examples of human diseases from using water with a significant amount of cyanobacteria blooms. When “blooming” biomass of blue-green algae accumulates in the coastal part and causes technical difficulties in supplying water to the water supply network, the formation of overseas zones and the death of hydrobionts. Existing methods of combating “blooming” have a number of significant drawbacks, for example, mechanical methods require high financial costs, and chemical ones are environmentally unsafe. The article presents the results of the scientific research of the All-Russian Research Institute of Irrigated Agriculture, Volgograd (Volgograd) on using biotechnology for natural water purification. The experiment on introducing Chlorella vulgaris IGF no. C-111 microalgae into the bays of the Volgograd reservoir was carried out on the basis of preliminary compilation of the hydrological characteristics of the reservoir bays, determination of hydrobiological and hydrochemical qualities of water. The aim of the work was to substantiate the technology of introducing Chlorella vulgaris IFR no. C-111 strain into the bays of the Volgograd reservoir and to obtain data confirming the scientific hypothesis – the expediency of using Chlorella vulgaris IFR no. C-111 strain to improve the hydrobiological and hydrochemical composition of natural water.