STRUCTURE AND INTERANNUAL DYNAMICS OF THE REGIONAL ECOSYSTEMS RADIATION BALANCE OF THE PLAIN CRIMEA

The research team calculated the values of the radiation balance elements of the plain Crimea ecosystems on the bases of open databases of climate data and GIS-modeling and, moreover, analyzed their spatial and temporal differentiation. It is revealed that the spatial distribution of the radiation balance is characterized by an increase in values from the center to the coast of the peninsular. It correlates with the spatial differentiation of both total solar radiation and all other elements of the short-wave part of the radiation balance. There is a significant excess of radiation balance values of the plateau landscape level ecosystems over values of the hydromorphic landscape level ecosystems. This difference is determined by the location of selected key areas on the western coast of the Crimean Peninsula, which is characterized by the maximum values of total solar radiation supply. The elements of the long-wave part of the radiation balance change in the opposite direction, compared with the short-wave part of the radiation balance, which is associated with an increase of air temperature and climate continentality in the direction from the coast to the center of the peninsula. Two periods were identified in the interannual dynamics corresponding to the change of the circulatory periods of the Northern Hemisphere. In general, the considered ecosystems are characterized by trends of increasing radiation balance values in conditions of growth of all its elements. Such growth is provided by significant increase of values during the second period compared with the negative trends of radiation balance values for a number of ecosystems in the first one.

BOTTOM FAUNA OF LAKE DONUZLAV UNDER CONDITIONS OF INDUSTRIAL SAND MINING

In 2019, the composition and quantitative representation of the zoobenthos in Donuzlav Lake, in the area of fine sediment discharge after the sand mining, and in the adjacent water area were studied. The accounting of the macrozoobenthos at the species level and of the meiobenthos at the major taxa level indicates the presence of a typical Pontic bottom fauna in the Lake, which has developed over 58 years of it existence. The benthic macrofauna was represented by a biocoenosis of Chara algae with Mytilaster lineatus, existing in a two-tier biotope – of a soft-bottom and of a Chara algaes developing on it. The epiphyton macrofauna quantitatively dominated the benthic macroinfauna. A total of 102 species and 7 superspecies taxa of the macrozoobenthos were registered in the identified biocoenosis. That increases the overall level of the macrozoobenthos representation up to 171 species and 9 superspecies taxa in Donuzlav for the period since 1981. In meiobenthos 11 taxa in the rank of type were recorded. The abundance and biomass of the macrozoobenthos averaged 34.658±1.655 ind./m2 and 316±93 g/m2 respectively, that is comparable with the previous studies. The average abundance of meiobenthos in the bottom biotope reached 247.2×103 ind./m2. Nematodes were the dominant group in meiobenthos, followed by harpacticids, with a combined share of 81 % in total meiobenthos abundance. The local impact of the discharging finely dispersed soil fractions to the benthic fauna of the southern part of the Donuzlav Lake was revealed. There was a 12, 3.5 and 2-fold decrease in abundance, biomass and number of macrozoobenthos species respectively and a 3.2-fold decrease in meiobenthos abundance, in the discharging area compared to the neighboring water areas of the Lake.

EVALUATION OF THE BIOLOGICAL ACTIVITY OF THE RHIZOSPHERE SORGHUM BICOLOR UNDER THE INFLUENCE OF MICROBIAL PREPARATIONS USING NO-TILL TECHNOLOGY IN THE CRIMEAN STEPPE

In steppe plants regularly lack of moisture and it affects the biochemical functions of their development. The aim of this research was to study the enzymatic activity of the Sorghum bicolor (L.) Moench rhizosphere grown by no-till technology under the influence of introduced microorganisms under conditions of moisture deficit. The growing season of Sorghum bicolor during the research period (2018–2020) was characterized by high temperature and arid conditions. The lack of precipitation reached 68.5 % in comparison with the average long-term indicators. It was revealed that the influence of the weather conditions of the year and the complex of microbial preparations (CMP) on the changes in the enzymatic activity of the S. bicolor rhizosphere was at the level of p≤0.05. IIBS (integral indicator of biological state) was calculated based on the level of activity of various enzymes in the soil. The value of IIBS with CMP is close to 80 %. It shows that no-till farming using CMP contributes to physiological stability of the rhizosphere. At the same time, the IBPS annually decreased by 61.1–92.8 % in the control variant without pre-sowing treatment of seeds with CMP, which indicates a slowdown of biological processes. The results of the studies proved that the adaptation of sorghum plants to the effects of abiotic environmental conditions is carried out by regulating the enzymatic activity of the rhizosphere by introducing microorganisms. Consequently, the use of microbial preparations is advisable for the cultivation of S. bicolor by no-till technology in steppe zone of Crimea.

ENVIRONMENTAL MANAGEMENT AND AQUATIC ECOLOGY IN SEARCH OF ANSWERS TO THE CHALLENGES OF THE TIME

Currently, the destruction of landscapes is taking place with a decrease in the sustainability and productivity of natural ecosystems. One of the main reasons for this is inadequate environmental management, which, as a rule, is based on inadequate outdated theoretical ecological concepts. The totality of accumulated data shows that real ecosystems can be in several alternative states and demonstrate relatively rapid changes in the regime of existence with significant, abrupt and permanent changes in structure and functioning. In this regard, the main ecosystem paradigm is currently being revised. From the theoretical concept of the unicity of the ecosystem stable state, ecology moves to the concept of the multiplicity of stable states in the ecosystem. The dynamics of ecosystems can be represented, according to K. Holling, in the form of an adaptation cycle with the alternation of four phases, the features of which are considered. The importance of no return points and possible uncertainty in the dynamics of ecosystems are shown. Ecosystems, in a certain sense, have memory, which is the reason for the hysteresis effect during multidirectional changes in systems. The necessity of developing approaches of adaptive ecosystem management based on this concept is shown. Which is especially important in cases of rapid transformation of natural ecosystems, such, as an example, in the Crimea after the cessation of the supply of Dnieper water to the North Crimean canal. The difficulties of transition to adaptive environmental management in modern conditions are analyzed.

FEATURES OF SEED GERMINATION AND EMBRYO DEVELOPMENT OF REPRESENTATIVES OF THE FAMILY RANUNCULACEAE

The ability of seeds to maintain viability for a long time without germination is one of the most important adaptive properties of plants. The article analyzes the dormancy types of seeds of the Ranunculacea family and describes the key factors affecting seed germination and embryo development (warm and cold stratification, exposure to gibberellic acid) under artificially created conditions. It is noted that five levels of seed morphophysiological dormancy are described for the representatives of this family: non-deep simple, deep simple, deep simple epicotyl, intermediate complex and deep complex, which are mainly associated with adaptation to survival in difficult climatic conditions. In the review, various types of dormancy are considered in terms of their adaptive significance for representatives of the Ranunculacea family. To overcome each type of dormancy, a set of optimal conditions is necessary, which correlates with the growing conditions of species or individual populations in natural conditions. Therefore, the development of techniques for overcoming the seeds dormancy under artificial conditions is closely related with the study of the ecology of a particular species and the natural conditions of growth. The analysis of literature data revealed a significant problem: 40 % of the analyzed sources did not indicate the type of dormancy of seeds of the representatives of the Ranunculaceae family and, probably, the list of morphophysiological dormancy levels will be supplemented in the course of further studies.

TRANSFORMATION OF THE HALOPHYTIC VEGETATION OF THE “SERDOBSKY SOLONETS” SERDOBSKY DISTRICT, PENZA REGION)

Halophytic vegetation is very rare in the forest-steppe zone. It was studied in the tract Serdobsky solonetsin the vicinity of Serdobsk (Serdobsky district, Penza region). The studies were conducted in the years 2009–2018, using the technique of geobotanical profiling. 80 trial areas were laid (35 in 2009 and 45 in 2008). Ecological and phytocenotic classification of plant communities is performed on the dominant principle. Comparison of two descriptions of vegetation with an interval of 10 years allows us to trace the transformation of halophytic vegetation after intensive anthropogenic impact (grazing and partial plowing) in different environmental conditions. The flora of Serdobsky solonets consists of 179 species of vascular plants, of which 13 species are included in the Red book of the Penza region (2013). The share of halophytic vegetation on the territory of Serdobsky solonetshas changed over 10 years: from 97.0 % to 63.8 %. Moreover, halophyte meadows occupied 67.0 % and halophyte steppes 30.0 % of the area in 2009. Now (2018) halophytic steppes make up 30.8 %, and halophytic meadows 33.0 %.The main stages of demutation of halophytic steppe and meadow vegetation were identified in various environmental conditions (meadows and steppes). The same stages of demutation were identified earlier for the South-Eastern Solonets (Neverskinsky district of the Penza region). However, a special stage of annual saline grasslands has been identified.This place requires protection due to the high level of floral and phytocenotic diversity. We offer to organize here a natural monument called “Serdobsky solonets”.

TAXOCENE MALACOSTRACA OF LASPI BAY WATER AREA (BLACK SEA)

The water area of Laspi Bay is located between the Cape Aya Nature Reserve and the coastal-acval complex near Cape Sarich. The benthic samples were collected during the summer period 2016–2019. The taxonomic diversity and current condition of the higher crustaceans, which live on the loose littoral and sublittoral bottoms of the bay, was assessed. 41 species of Malacostraca have been identified. They belong to 6 groups. In bay other Arthropoda representatives were found: Amphibalanus improvisus (Darwin, 1854) and Harpacticoida. The average biomass of higher crustaceans was 0.454±0.228 g/m2. The main role in its formation is played by Decapoda and is dominated by Diogenes pugilator. The average number of Malacostraca was 280±158 ind./m2. The highest percentage of occurrence and high density of settlement were recorded for Amphipoda. The ranked series by density index was headed by D. pugilator, Echinogammarus foxi, Centraloecetes dellavallei and Echinogammarus karadagiensis. The highest numbers were recorded at stations in the flood zone (0–0.5 m). High abundance and biomass concentrations of Malacostraca were recorded at the stations with sand and pebbles.

THE CURRENT STATE OF THE WATERCOURSES OF THE LAKE SEGOZERO BASIN (SEGOZERO RESERVOIR, REPUBLIC OF KARELIA, RUSSIA)

The chemical features and the structure of biological communities in the in the three watercourses of Segozero Lake basin. Analysis for the species composition, abundance and biomass of phytoperiphyton, zooplankton, and zoobenthos was carried out. The effect of natural and anthropogenic factors on the formation of the chemical features and structure of lake hydrobiocenoses was analyzed. Variations in the structure of aquatic organism communities are due primarily to specific hydrographic and hydrological characteristics of river stretches. The paper is discussed the main principles of the changes in a structure and functioning of hydrobiont communities in rivers. The trophic status of the rivers, their saprobiological slate, and the significance of individual communities and biotic indices for bioindication of the ecological state of the rivers, are estimated. We concluded that consideration of three groups of organisms enables more comprehensive and reliable monitoring than assessment based on a single group. The abundance and biomass of phytoplankton, phytoperiphyton, zooplankton, and zoobenthos suggest the relatively high degree of their development in lake water, as well as their activity and stability. A peculiarity of the structure of hydrobiocenoses is that they consist of species with appreciably different sizes: from several microns to several centimeters. Therefore, the lists of species dominating in terms of abundance and biomass differ appreciably.

ORNAMENTAL ARBOREAL PLANTS IN SETTLEMENTS OF THE SOUTH-EASTERN CRIMEA (ON THE EXAMPLE OF MALORECHENSKOYE AND RYBACHYE SETTLEMENTS)

The results of research of green areas in localities Malorechenskoye and Rybachye (South-Eastern Crimea) are presented. Large-scale landscaping of the studied territory was carried out in the 60-80-ies of the XX century. Modern structure of green spaces is typical for coastal settlements – basically, these are parks of recreational complexes, with high concentration of diversity of trees and shrubs species. A historical park (the oldest one) in the South-Eastern Crimea (late 50s – early 60s of the XIXth century) is also located in Malorechenskoye. The researches made taxonomic, botanical-geographical and biomorphological analysis of dendroflora. The frequency of occurrence of species, the condition of plants, as well as the degree of their drought and frost were assessed. The studied dendroflora includes 106 species belonging to 75 genera from 43 families. The species diversity of trees and shrubs in Rybachye is higher than in Malorechenskoye (89 and 67, respectively). At the same time, 13 species are widely distributed in both settlements, the most numerous of which is Cupressus sempervirens. It was revealed that species of the Mediterranean floristic region predominate (31.1 %), and representatives of native Crimean flora take a significant place (34.9 %). The leading position in the biomorphological structure of the dendroflora belongs to deciduous trees (25.5 %), followed by deciduous and evergreen deciduous shrubs (19.8 % each), and coniferous trees (17.0 %). The species diversity of deciduous shrubs and coniferous trees is significantly higher in Rybachye than in Malorechenskoye. Most plants are adapted to local climatic conditions: 57.5 % of species are not damaged by drought, the rest suffer from it in different degrees; 78.3% of species are frost-resistant, others are periodically damaged by low temperatures and need better protected from frost and cold winds planting sites. The absolute majority of species (95.3 %) are in good condition. Plants Aesculus hippocastanum, Buxus balearica, B. sempervirens, Euonimus japonica are more or less affected by pests and diseases. Special attention should be paid to the preserve the historical park in Malorechenskoye and to give it a protected status.

BENTHIC FAUNA OF THE SOUTH-WESTERN PART OF THE SEA OF AZOV: TRANSFORMATION OF MACROZOOBENTHOS BIOCOENOSIS AT THE BEGINNING OF THE XXI CENTURY

Cerastoderma biocoenosis has been one of the main biocoenoses that occupied the most extensive areas and prevailed in quantitative development in the benthos of the Sea of Azov for more than 80 years, since the first quantitative description were made there in 1930s. However, the penetration of the bivalve Anadara kagoshimensis (a recent invader to the Black Sea basin) to the Sea of Azov in 1989 determined the beginning of subsequent biocoenotic changes. Systematic benthic surveys were conducted in 2016–2017 during cruises #84, #86, #90, #96, #100 aboard R/V “Professor Vodyanitsky” on the extensive south-western section of the Sea of Azov. The results of the surveys revealed the formation of a single Anadara biocoenosis, in which the previously dominant native species Cerastoderma glaucum and Abra segmentum became subdominants. The present research continues the analysis of these data. Its purpose is to assess the features of transformation the Cerastoderma biocoenosis, which was the main native biocoenosis in the Azov Sea – to the biocoenosis of alien species Anadara kagoshimensis. The paper uses materials of three time-periods corresponding to different levels of salinity of the Sea of Azov: 1930s (9.3–11.1 %), the 1950s (11.6–12.1 %) and 2016–2017 (13.5–14.0 %). The results of the analysis showed a high level of similarity (60 %) in the composition of the cores of two native biocoenoses of Abra and Cerastoderma and the new Anadara biocoenosis. The transformation of the native biocoenoses on the southwestern section of the basin into the Anadara biocoenosis resulted both from the successful expansion of A. kagoshimensis and a decrease in the quantitative development of the aboriginal species complex under the conditions of increasing salinity of the basin. A compensatory increase in the quantitative development of zoobenthos was observed in 2016–2017 exceeding that of the 1930s due to A. kagoshimensis. From 1930s to 1950s the number of species in the Cerastoderma biocoenosis in the groups of Mollusca, Polychaeta and “Other species” did not change significantly, but in Crustacea group it decreased by more than 2 times. From 1950s (Cerastoderma biocoenosis) to 2016-2017s (Anadara biocoenosis) there was a nearly two-fold increase in the number of species in the groups of Mollusca, Polychaeta and “Other species” while the number of Crustacea species increased slightly.