Watercourses of the Carpathian Biosphere Reserve as a habitat, reproduction and conservation of fish gene resources

Natural watercourses, their forage base, and ichthyofauna of the Carpathian Biosphere Reserve of the Transcarpathian region have been studied. Information on the species composition is given, the names and genus of some of the specimens are specified. The systematic structure is reflected, the functional role of roundworms and fish in the studied ecosystem, dominant and endangered species are determined. Their geographical distribution in different zones of watercourses, structural-comparative analysis with the species registered in the Transcarpathian region are carried out. It is established: a characteristic feature of the ichthyocenosis is the presence of a significant number of salmon and aboriginal species. The urgency of research – global warming, human activities change the hydroecosystem of the reserve, have a negative impact on aboriginal fish species, which are indicators of changes in hydrological regime and microclimate, lead to the settlement of their areas indigenous. In total, we recorded 42 species belonging to 7 series, 11 families, 33 genera in the studied water areas. Additionally, 12 undescribed were identified. The growth of the total number of species by 66.67 % was due to allochtons. Emphasis was placed on the need for further genetic research, which could be a source of additional information on fish biodiversity in the Carpathian Biosphere Reserve and in the Tisza River, a tributary of the Danube.

ANALYSIS OF THE STATE OF THE NURA RIVER FORAGE BASE

This article presents the results of research on the state of the Nura River forage base. The species composition, total mass, and abundance of zooplankton and zoobenthos were determined in the reservoirs. The zooplankton of the studied reservoirs is also diverse and includes widespread species that can be divided into 3 groups: rotifers, branched-moustached, oar-footed crustaceans. In the studied reservoirs, 40 taxa were noted as part of zooplankton, of which 11 species are rotifers, 16 are branched crustaceans, and 13 are oar-footed crustaceans. A.priodonta, P.remata and F.longiseta are dominant in the frequency of occurrence in rotifers, D.сuclata and D.galeata in branchiformes, and representatives of the genus Mesocyclops in copepods. The total species diversity of the benthic complex of the Nura River contains more than 100 species. The abundance of small bivalve mollusks of the families Euglessidae and Pisidiidae, which form the basis of benthic biomass, is very high in the rheotic areas. The bottom population of limnic and areas close to them in terms of characteristics is more diverse in species terms. The dominant species here are the chironomids Chironomidae spp., which had a high number. The forage base of the river sections corresponds to the environmental conditions and allows a certain herd of commercial fish to exist.

Role of kura clover (Trifolium Ambiguum bieb.) of Vys variety in the growth of the forage base of the Tambov region

In the conditions of the forest-steppe of the Central Black Earth region, the issue of the sustainable development of forage production, which can be increased through the expansion of the range of cultivated species of perennial legumes, has become relevant. The need to increase the share of areas of perennial grasses is connected with the fact that natural lands and annual forage crops have low productivity. Forage grasses are characterized by a number of unique economically valuable properties and characteristics. In this regard, there is an urgent need to increase their sown areas, as well as to improve natural lands, create hayfields and pastures. One of the limiting factors is the insufficient provision of seeds for a new fodder crop - Vys clover of a kura variety. It is kura clover that plays an important role in the creation of a solid forage base for animal husbandry in the Tambov region. Kura clover (Trifolium ambiguum Bieb) is characterized by a number of valuable traits and properties. In this regard, for the first time in the Central Black Earth Region, its biology and morphological development began to be studied and the optimal terms and methods of sowing this perennial legume crop are being developed. It will allow obtaining stable seed yields. The technology for obtaining seeds of this forage crop of the Vys variety in the forest-steppe conditions of the Central Black Earth Region is currently in the process of development. Therefore, the ongoing research on agrotechnical methods of the cultivation of kura clover seeds is very relevant and the development of individual agricultural methods of its cultivation technology of seeds is one of the important tasks of forage production.

Innovative elements in the organization of a green conveyor

Relevance and methods. The article considers possible options for restoring the forage base of the non-Chernozem zone. The research was carried out on the experimental field of the Novgorod Research Institute of Agriculture in 2017–2019. The studies were carried out with perennial and annual traditional and introduced forage crops of domestic selection.Results. It has been experimentally established that the cultivation of traditional forage crops of new varieties of domestic selection contributes to an increase in the productivity of the forage hectare. The qualitative characteristics and yield level of the green mass of annual introducents were determined, terms of formation of the mowing mass of crops in the climatic conditions of the Novgorod region. New forage plants complement the green conveyor with innovative elements, increasing the choice of forage harvesting methods.

WATER BIOLOGICAL RESOURCES OF REPUBLIC OF MORDOVIA. SURA RIVER

The article considers the results of comprehensive fisheries research held in 2009–2015 in the Sura River, the main water body of the Republic of Mordovia. The Sura River ranks the second place after the Moksha River. Forage base studies have shown the underutilization of zoobenthos and phytoplankton. According to the average indicators of the feed base over the above period, the production capacities of the river were calculated, and made about 113.5 tons, or 141.9 kg / ha. Of these, the native ichthyofauna (zooplankton, zoobenthos) effectively use 71.0 kg / ha. The total number of fish aged 3+ years with mass more than 10 g in the Sura within the borders of Mordovia is estimated at 1028.8 thousand species; ichthyomass is 39.1 t or 49 kg / ha. At the same time, the proportion of juveniles aged 0–2 +, as well as small fish species whose biomass is estimated at 81 kg / ha, is big. The increase in fish production was calculated and the total catch quotas were determined, according to the most valuable commercial species in the ichthyofauna - roach. Within the borders of Mordovia they make up to 16 tons, in the Middle Sura - up to 40 tons. When carrying out fish reproductive and conservation measures the stocks of aquatic biological resources in the river can increase by 2–3 times due to valuable large fish species, and the catch - from 20 kg / ha to 40-60 kg / ha

Spatiotemporal patterns in trophic niche overlap among five salmonines in Lake Michigan, USA

Native lake trout (Salvelinus namaycush) and introduced Chinook salmon (Oncorhynchus tshawytscha), coho salmon (Oncorhynchus kisutch), steelhead (Oncorhynchus mykiss), and brown trout (Salmo trutta) are major predators in Lake Michigan’s complex ecosystem and collectively support a valuable recreational fishery, but declines in their primary prey, alewife (Alosa pseudoharengus), have raised ecological and management concerns about competition and prey allocation. We applied niche overlap analysis to evaluate competition among salmonine predators during rapid forage base change in Lake Michigan. δ13C and δ15N stable isotope ratios indicated that lake trout had a unique trophic niche from inclusion of offshore and benthic prey, with <29% lake-wide niche overlap with Chinook salmon, coho salmon, and steelhead. Brown trout had moderate overlap with other species (45%–91%), while Chinook salmon, coho salmon, and steelhead had high overlap (71%–98%). Regional differences in isotopic signatures highlighted the potential importance of subsystem differences in fish diets in large aquatic systems. The uniqueness of the lake trout niche, and broadness of brown trout and steelhead niches, suggest these species may be resilient to forage base changes. This study further demonstrates how niche overlap analysis can be applied to tease apart competitive interactions and their response to ecosystem change.

The creation of special commodity fish farm on the black sea lakes of Odesa region

Pond fisheries are one of the promising areas of fisheries in Ukraine and the world. The vast resources of the inland waters of our country are a reliable source of valuable fishery products. However, the potential of this source is not fully exhausted. Therefore, a significant increase in the production of commercial fish can be achieved as a result of the construction of new commercial fisheries and factories, whose task is to recreate fish stocks. One of the leading places among all kinds of outdoor activities is sports and amateur fishing. Capture fishing has become a permanent fixture for hundreds of millions of people around the world. It is estimated that in Ukraine sport and recreational fisheries cover about 10 % of the population. The purpose of the work was to find out the current state of fish productivity of the Black Sea ponds of Odesa region for the creation of specialized fisheries. The fish productivity of the Black Sea ponds, the forage base and the ichthyofauna were investigated, the most valuable representatives of the ichthyofauna for amateur fisheries in these reservoirs were identified, the recommendations on the creation of a special cultural fishery on the Black Sea ponds were provided. It is established that the feed base in the Black Sea ponds for fish young is quite rich and varied. The current state of development of the forage base indicates the possibility of successful fishing activities and in particular the development of recreational fisheries. In case of intensification of economic activity there is a need to carry out a certain complex of fish-and-melioration works. As a result of the conducted researches it is established that the Black Sea ponds should be used for the creation of cultural fisheries for the purpose of organizing amateur fisheries, and the formation of ichthyocenosis should be carried out by purposeful fishing of valuable fish species suitable as objects of amateur and sport fisheries. Creating appropriate conditions for amateur fisheries as a popular way of recreational recreation of a large part of the population of Ukraine involves solving a number of biological, environmental and legal issues related to the reproduction and acclimatization of fish, the organization of sports and recreational fisheries, taking into account the characteristics of reservoirs, the impact of ecological and climatic conditions fisheries, etc.