Akimov L.M. TRENDS IN CHANGES IN THE THERMAL REGIME IN THE ARID AND ADJACENT TERRITORIES OF THE EUROPEAN PART OF RUSSIA IN THE SUMMER PERIOD // Arid ecosystems. 2021. V.27. № 4 (89). P. 3-12.

Received June 16, 2021. After revision June 30, 2021. Accepted July 01, 2021.

The paper presents the results of the analysis of trends in the average monthly air temperature, arid lands of the European part of Russia and the territories associated with them, in the summer period, as well as estimates of their direction and speed of temperature changes in the second half of the twentieth and early twenty-first centuries. Against the background of the global climate, the regional features of the thermal regime of the European territory of Russia (ETR) are studied. The analysis of latitudinal and longitude quantitative indicators of changes in the thermal regime, with a spatial distribution in the study area, is given. A significant increase in air temperature was found in the territories of arid lands of Russia, where the trend of temperature increase is significantly higher than the data presented in the Assessment Reports and amounted to 0.066oC over 10 years.

Keywords: air temperature, global climate, European territory of Russia, thermal regime, arid lands, trend, variability.

DOI: 10.24412/1993-3916-2021-4-3-12

Shumova N.A. Quantitative climate indicators as applied to the assessment of hydrothermal conditions in the Republic of Kalmykia // Arid ecosystems. 2021. V.27. № 4 (89). P. 13-24.

Received April, 27 2021. After revision June 30, 2021. Accepted July 01, 2021.

 The study is aimed at studying the reliability of estimates of the dynamics of hydrothermal conditions in the Republic of Kalmykia for the period 1966-2017, obtained based on the use of quantitative climate indicators, namely, the Selyaninov hydrothermal coefficient, the moisture coefficient, the Thornthwaite aridity index, the Köppen method and the Holdridge scheme. The analysis of the results obtained showed that the greatest reliability is inherent in climatic estimates made on the basis of the Selyaninov hydrothermal coefficient, the Köppen method and the Holdridge scheme. The estimates made using the Thornthwaite aridity index do not reflect the current climatic conditions of the study area and are unreliable.

Keywords: quantitative indicators of climate, natural zones, regional level, Republic of Kalmykia.

Financing.  This research was carried out within the state assignment of Water Problems Institute of the Russian Academy of Sciences, Section 2.6 “Evolution of Terrestrial Ecosystems under the Changing Natural Conditions”, Theme “Modeling and Forecasting of the Processes of Water and Ecosystems Quality Restoration under Various Scenarios of Climate Change and Anthropogenic Activities” No. 0147-2018-0002, state registration No. АААА-А18-118022090104-8.

DOI: 10.24412/1993-3916-2021-4-13-24

Gudko V.N., Usatov A.V., Azarin K.V. ANALYSIS OF HYDROTHERMAL CONDITIONS IN THE ROSTOV REGION IN THE PERIOD 1960-2019 // Arid ecosystems. 2021. V.27. № 4 (89). P. 25-31.

Received April, 22 2021. After revision June 30, 2021. Accepted July, 01 2021.

Based on data from six meteorological stations in the Rostov region in the period 1960-2019, the tendencies of changes in air temperature, precipitation, and hydrothermal conditions, expressed by the Selyaninov hydrothermal coefficient, were analyzed. For all meteorological stations, a significant trend was determined for the increase in the average annual air temperature and the sums of temperatures above 10 °C. The annual amount of precipitation had a significant upward trend only at the Chertkovo meteorological station, at the other five meteorological stations — an upward trend. On the background of an intensive increase in temperatures, a tendency for a decrease in the values of the Selyaninov hydrothermal coefficient for the Gigant, Rostov-on-Don, Taganrog and Tsimlyansk meteorological stations was noted. At the meteorological stations Chertkovo and Remontnoye, the increase in temperatures was compensated by an increase in the amount of precipitation; as a result, a tendency to an increase in the values of the Selyaninov hydrothermal coefficient was noted. Hydrothermal conditions at six meteorological stations in the period 1960-2019 were characterized as dry, and the mean annual value of HTC varies within 0.64 — 0.82. The driest conditions are typical for meteorological stations located in the east and north-east of the Rostov region. Based on the calculated trends, it can be concluded that in the period 1960-2019 for the meteorological stations Gigant, Rostov-on-Don, Taganrog and Tsimlyansk, arid warming is characteristic, while the meteorological stations Remontnoye and Chertkovo are characterized by humid warming.

Keywords: air temperature, precipitation amount, hydrothermal conditions, Selyaninov hydrothermal coefficient, arid warming, humid warming, Rostov region.

Financing. The work was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation within the framework of the state assignment in the field of scientific activity (No. 0852-2020-0029).

DOI: 10.24412/1993-3916-2021-4-25-31

Petrushina M.N., Gunya A.N. SEMIARID INTERMONTANE DEPRESSONS OF THE NORTHERN CAUCASUS: LANDSCAPES AND LAND USE TRANSFORMATION // Arid ecosystems. 2021. V.27. № 4 (89). P. 32-40.

Received May, 19 2021. After revision June, 30 2021. Accepted July, 01 2021.

On the basis of long-term field studies in semiarid intermontane depressions of the North Caucasus, the features of their landscape structure and modern changes in landscapes associated with different levels of anthropogenic load have been revealed since the end of the 20th century. In the Itum-Kalinskaya depression, due to the termination of intensive economic use (mainly grazing) in the early 1990s, the pressure on landscapes decreased and the restoration of their biogenic components began. This led to the suspension of aridization, which was noted by many authors in the 1970s-1980s. In mountain meadow-steppe landscapes, the destruction of cultural and landscape elements (plow terraces, irrigation system, etc.) is taking place. In the Bylym Basin, with a general decrease in anthropogenic load in the 1990s, an extreme unevenness of its distribution was noted, which led to the degradation of some landscapes and an improvement in the state of others. The load on mountain-steppe landscapes has increased, which gradually transformed into anthropogenic modifications. The strongest anthropogenic disturbances are observed in landscapes on the slopes of the northern exposure, which are adjacent to the main residential and economic zone and are used almost all year round. The contrast between landscapes with different levels of use is increasing, mainly due to the greater pressure on them near settlements, while the landscapes distant from them may not be used at all.

Keywords: semi-arid depressions, North Caucasus, land use transformation, landscape change, landscape structure.

Financing. The work was carried out on the topic of the State Task of the Department of Physical Geography and Landscape Studies of Moscow State University «Factors and processes of spatio-temporal organization of natural and anthropogenic landscapes» (Contract no. 1.8, CITIS number — 121051300176-1), as well as on the topic of the State Task of the Institute of Geography of the Russian Academy of Sciences (No. 0148-2019-0007) «Assessment of physical-geographical, hydrological and biotic environmental changes and their consequences for creating the foundations of sustainable nature management».

DOI: 10.24412/1993-3916-2021-4-32-40

Rasal V., Dhakad M., Khandal D. ASSESSING ANTHROPOGENIC PRESSURE OF FOREST VILLAGES IN SEMI-ARID FOREST ECOSYSTEM IN WESTERN INDIA USING CUMULATIVE DISTURBANCE INDEX (CDI) // Arid ecosystems. 2021. V.27. № 4 (89). P. 41-49.

Received January ,17 2021/ After revision June, 30 2021/ Accepted July , 1 2021.

Human communities living in and around the forest are highly dependent on the forest for subsistence and livelihood. Kailadevi Wildlife Sanctuary (KWLS), is an important landscape for securing tiger population in semi arid western India. Human population and their livestock residing in KWLS are exerting anthropogenic pressure on the habitat. Understanding the nature of the anthropogenic pressure is essential to mitigate anthropogenic pressure, reduce negative human-wildlife interactions and improve habitat for wildlife. Anthropogenic disturbance caused by 12 enclave villages inside KWLS was measured using cumulative disturbance index (CDI). Livestock grazing and extraction of wood was found to be the most pressing anthropogenic pressures in the KWLS. Outcome of the study will help the forest managers to devise strategies to improve the habitat quality for the wildlife.

Keywords: anthropogenic pressure, cumulative disturbance index (CDI), Kailadevi wildlife sanctuary.

DOI: 10.24412/1993-3916-2021-4-41-49

Kulik A.K., Kulik K.N., Vlasenko M.V., Sukhorukikh Yu.I., Biganova S.G. Formation of the water regime on the sands of the Archedinsko-Don massif depending on the plant communities distribution // Arid ecosystems. 2021. V.27. № 4 (89). P. 50-58.

Received December, 12 2020. After revision June, 30 2021. Accepted July, 01 2021.

The remote monitoring of the territory and the Archeda-Don interfluve sand massif landscape-ecological instrumental profiling made it possible to determine the soil and vegetation cover state, the level and slopes of groundwater. The soils salinization degree on various sands types was revealed. The water-soluble salts amount is 0.001% on open sands in the blowing hollows, and 0.03-0.05% on chernozem-like soils. Massifs where plant litter is accumulated have a salinity of 0.05-0.07%. Natural forest stands consist of the following species: birch (Bétula), alder (Alnus), oak (Quércus), aspen (Pópulus trémula) and willow (Sálix). In the XIX century, the common pine (Pínus sylvéstris) was introduced into the culture. A large number of forest sites and their koloks-like placement caused by the close occurrence of groundwater. Maximum productivity is achieved by alders (Alnus) with a wood reserve of 500 m3/ha. Their height in areas with stagnant ground water reaches 12-15 m. The birch trees (Bétula) koloks are located on depressions. On clay areas there are rare stands of petiolate oak (Quércus róbur) with a height of 8-12 m. The pine (Pínus sylvéstris) growth on chernozem-like multiphase sandy loam soils and on single-phase overgrown sands with thick turf-steppe soils is shown. There were identified 5 dominant sand types, where the area of forage lands is 171536 ha and forest sites – 50584 ha. All sand types have forest sites in the form of koloks and pine crops. Overgrown tuberous-ridge (seropeski) sands are in dominant. The total grass productivity according the sand types on 170625 hectares of pasture land of the massif is 370.7 thousand hectares. The most productive are overgrown closed depressions and ancient watercourses (3.0 t/ha). The received research results are relevant for a conceptual model of sandy lands optimal use development.

Keywords: sandy soils; salinity; soil moisture; vegetation; forest massifs; forest cover; forage lands.

Financing. The work was carried out on the topic of research of the Federal Scientific Center for Agroecology, Integrated Land Reclamation and Protective Afforestation of the Russian Academy of Sciences No. AAAA19-119042290014-5 «Theoretical foundations of water resources management in the forest-agrarian development of arid territories of the Russian Federation on the basis of a dynamic model of the water balance of the region, mathematical modeling of the processes of formation and dynamics of groundwater and surface waters, assessment of the impact of climate change and anthropogenic loads on the agro-resource potential and forest conditions».

DOI: 10.24412/1993-3916-2021-4-50-58

Kungurtsev A.J., Suleymanov R., Ovsyannikov V.V., Savelyev N.S., Abakumov E.V., Asylbaev I.G. HUMUS STATUS OF SOILS OF ARCHAEOLOGICAL MONUMENTS OF THE EARLY IRON AGE (REPUBLIC OF BASHKORTOSTAN) // Arid ecosystems. 2021. V.27. № 4 (89). P. 59-69.

Received February, 15 2021. After revision April, 29 2021. Accepted July, 01 2021.

The organic matter of modern and buried humus horizons of soils has been studied on the example of the archaeological monuments Akberdinskoe-II, Shipovskoe and Okhlebininskoe-II settlement (Kara-Abyz culture of the early Iron Age of the IV century BC — the turn of the II-I centuries BC). Archaeological sites are located on the territory of the Iglinsky district of the Republic of Bashkortostan within the forest-steppe zone. Morphological and physico-chemical properties of soils are determined. Additionally, methods of spectrophotometry and 13C NMR spectroscopy were used. On the territory of archaeological sites, dark gray forest soils of loamy granulometric composition are common. The thickness of the daytime and buried humus horizons of soils is 11-30 cm . Organic matter is represented by fulvate-humate, humate and humate-fulvate types of humus. The group composition is dominated by humic acids, and among the fractions of humic acids – the fraction of GC-2. The results of spectrophotometry showed a more mature state of the aromatic part of humic acid molecules for buried humus horizons compared to modern humus horizons. Humic acid molecules of the organic matter of modern humus horizons, according to the results of 13C NMR spectroscopy, correspond to the conditions of the chernozem type of soil formation. In general, the modern intensification of climate aridization in the forest-steppe zone of the Republic of Bashkortostan originates, according to archaeologists, from the middle of the IV century BC and the turn of the II-I centuries BC In the soil cover of archaeological sites at the time of observation of the change in the type of soil formation was not found.

Keywords: organic matter, archaeological monument, buried soils, Kara-Abyz culture, forest-steppe.

Funding. This research was carried out within the state assignment of the Ministry of Science and Higher Education of the Russian Federation (Ufa Federal Research Centre of the Russian Academy of Sciences) No. 075-00326-19-00, Theme “Studying the Risks of Soils Desertification in the Steppe Zone of the South Ural Region: Factors, Trends and Development of Ways to Reduce Its Negative Consequences” No. AAAA-A18-118022190102-3; and supported by the Russian Foundation for Basic Research, Project No. 17-11-02001-OGN “Cultural and Historical Processes and Changes of the Natural and Climatic Conditions during the Early Iron Age in the Forest-Steppe Territory of Aral Region” (Institute of History, Language and Literature of Ufa Federal Research Centre of the Russian Academy of Sciences). The humic acids were studied in the Scientific Park of Saint Petersburg State University (“Magnetic-Resonance Research Methods” and “Methods for Analysis of Matter Composition” resource centers).

DOI: 10.24412/1993-3916-2021-4-59-69

Rakhimova N.K., Rakhimova T., Adilov B.A., Tamambetova Sh.B., Polvonov F.I. CURRENT STATE CRAMBE EDENTULA FISCH. & C.A. MEY. EX KORSH. ON THE PLATO OF USTURT IN UZBEKISTAN // Arid ecosystems. 2021. V.27. № 4 (89). P. 70-76.

Received February, 1 2021. After revision June, 30 2021. Accepted July, 01 2021.

 The article is devoted to the assessment of the state of the ontogenetic structure of the rare species Crambe edentula Fisch. & C.A. Mey. ex Korsh., growing in the Karakalpak part of Ustyurt. The study showed that in the ecological-cenotic conditions of Ustyurt, the studied cenopopulations are normal, mostly incomplete. The characteristic ontogenetic spectrum for C. edentula is centered due to an increase in the life span of individuals in a mature generative state and poor seed renewal. Ontogenetic spectra of cenopopulations do not coincide with the characteristic one. The spectra of specific cenopopulations are left-sided and right-sided, which is associated with ecological habitat conditions and fluctuations in weather conditions.

Keywords: Ustyurt plateau, infrastructure development, endemics, rare plant species, ontogenetic structure, age and efficiency of cenopopulations.

DOI: 10.24412/1993-3916-2021-4-70-76

Rumiantsev V.Yu. distribution of steppe marmot on the russian plain in the histortical past: cartographic review // Arid ecosystems. 2021. V.27. № 4 (89). P. 77-85.

Received November, 20 2020. After revision December, 1 2020. Accepted July, 01 2021.

Changes in distribution of steppe marmot (Marmota bobak Müll.) during the history time always aroused and are of interest to specialists. Available studies give the information about the sites of marmot meetings as lengthy text descriptions that causes difficulties for perception and analysis of material. Solution of this problem is possible using the modern cartographic methods. In present work we generalized the known information about historical distribution of steppe marmot in cartographic form using the actual GIS technologies. The further analysis of results will enable to clarify significantly the details of steppe marmot distribution on the Russian plain during the history period – especially because of natural features of marmot preferred habitats.

Keywords: Steppe marmot, Marmota bobak Müll., Russian plain, sites of historical locations, cartographical methods, GIS technologies.

Acknowledgement. The author is sincerely grateful to V.A. Tatarsky for providing a copy of the map of V.A. Chernaya and for many years of friendly cooperation in the study of marmots. The author is also grateful to D.A. Khitrov and A.A. Golubinsky for effective and fruitful cooperation in processing the materials of the General Survey

DOI: 10.24412/1993-3916-2021-4-77-85

Malinovskaya Y.V., Minoranskiy V.A., Kolesnikov S.I. Number of breeding in the territory of the Rostovsky Reserve of Pelicans (Pelecanidae) and the causes of fluctuations in numbers // Arid ecosystems. 2021. V.27. № 4 (89). P. 86-92.

Received December, 12 2020. After revision June, 30 2021. Accepted July, 01 2021.

There were estimated a population size and nesting sitesof Dalmatian pelican (Pelicanus crispus) and Great White Pelican (Pelicanus onocrotalus) on Rostov Nature Reserve territory since 1995 to 2020. Establishing the reserve enabled the conservation of the bird species on the territory. The Dalmatian pelican is a near threatened and regularly nesting species and the Great White pelican is the least concern and rarely nesting species what can be explainedby their biological features. In the research there was made a nesting places specification. The research shows that drying out waters, increasing of water salinity, fish resources reduction could be defined as a deterrent factors for population size of the pelican species.

Keywords: Rostov Nature Reserve, Pelecanus crispus, P. onocrotalus, nesting sites, abundance, limiting factors.

Acknowledgement. The authors were assisted in conducting research by the staff of the Rostov Nature Reserve (A.V. Chekin, L.V. Kletz, A.D. Lipkovich, S.V. Moskalenko, etc.), employees of the Association (V.I. Dankov, A.G. Borodin, etc.) and the SFU (A.V. Tikhonov, Ya.Yu. Podgornaya, etc.), to whom the authors bring sincere gratitude.

DOI: 10.24412/1993-3916-2021-4-86-92

Abaturov B.D., Gorbunov S.S., Koshkina A.I. FEATURES OF FORAGE VEGETATION AS ONE OF THE POSSIBLE CAUSES OF MASS DEATH OF SAIGA ANTELOPE ON STEPPE PASTURES // Arid ecosystems. 2021. V.27. № 4 (89). P. 93-100.

Received April, 18 2021. After revision June, 30 2021. Accepted July, 01 2021.

Modern climatic changes, weakening of the anthropogenic pasture load, the growth of steppe fires, have caused the expansion and dominance of grasses vegetation on the steppe pastures of Russia and Kazakhstan since the end of the 20th century, which caused a deterioration in the forage quality of pasture vegetation, was one of the reasons for the depression of the saiga population and, of the increase in cases of mass mortality of saigas. Mass deaths of saigas occurred in Kazakhstan in 2015, when about 200,000 animals died. A large number of different versions have been put forward about the causes of death: from an infectious disease (hemorrhagic septicemia), toxic forage plants, unfavorable weather conditions, to the destructive effect of rocket fuel. In this article, we have considered a different versions of death associated with the negative effect of low-quality food in places of death of saigas. It has been shown that the supply of food to saigas on steppe pastures consistently decreases with an increase in the abundance of grasses in forage vegetation. Suitable pastures that provide adequate nutrition for breeding saigas include pastures with a share of grasses in the aboveground phytomass of no more than 30%. If this level is exceeded, the pastures do not provide the necessary level of nutrition for the breeding saigas and are unsuitable for them. It is possible that during the spring migration the saigas found themselves within the steppe regions with a predominance of turf grasses (65-75%), exceeding their permissible (threshold) abundance (30%). This condition of the pasture did not provide the necessary nutrition, caused a weakening of animals during the rearing period, promoted the activation of infectious septicemia in breeding saigas, which, possibly, with the combined action of both factors, led to their mass death.

Keywords: Saiga antelope, steppes of Kazakhstan, steppe fires, abundance of grasses, suitability of pastures, mass mortality of saigas, pasteurellosis, hemorrhagic septicemia, forage quality of vegetation, forage digestibility, forage availability.

Financing. The work was carried out under a grant of Russian Foundation for Basic Research, project No. 18-04-00172: «Toxic components in the vegetation of natural pastures as indicators of the quality of forage resources, their impact on food security and the state of populations of herbivorous mammals in terrestrial ecosystems.»

DOI: 10.24412/1993-3916-2021-4-93-100

Vlasova O.K., Daudova T.I., Bakhmulaeva Z.K., Magadova S.A., Magomedov G.G. ABOUT BIOTECHNOLOGICAL POTENTIAL OF THE PRODUCTIVE RESOURCES OF GRAPES GROWN IN ARID CONDITIONS // Arid ecosystems. 2021. V.27. № 4 (89). P. 101-106.

Received April, 28 2021. After revision May, 27 2021. Accepted July, 01 2021.

 The article presents the results of studying the biotechnological properties of grapes of the introduced variety Moldova, cultivated in various soil and climatic conditions of arid areas of the plain and foothills of Dagestan.The peculiarities of the synthesis of the components of the carbohydrate, acid, nitrogen, phenolic, amino acid and vitamin composition of grapes, depending on the place of its cultivation, are revealed.It is noted that even with low moisture availability and high values of the sum of active temperatures, the grapes of the Moldova variety, growing in Dagestan, are able to synthesize a large amount of valuable nutrients.The ecological plasticity and technological versatility of this variety is shown, the possibility of obtaining high-quality wine materials from it for the production of sparkling and original special wines is experimentally proved.

Keywords: plain, foothills, arid conditions, Moldova grapes, wine material, biologically active substances, synthesis of components, sum of active temperatures.

Financing. The work was carried out with the financial support of the RAS Presidium Program No. 41 «Biodiversity of natural systems and biological resources of Russia».

DOI: 10.24412/1993-3916-2021-4-101-106

Yermolaeva N.I., Fetter G.V. THE INFLUENCE OF THE IONIC COMPOSITION OF WATER ON THE STRUCTURE OF THE ZOOPLANKTON OF THE LAKES OF THE TAZHERAN STEPPE (WESTERN BAIKAL REGION) // Arid ecosystems. 2021. V.27. № 4 (89). P. 107-117.

Received July, 13 2021. After revision June, 30 2021. Accepted July, 01 2021.

An assessment of the modern state of the zooplankton of diverse lakes of the Tazheran steppe and the identification of the features of the formation of the structure of communities depending on the change in the ionic composition of water under the influence of changing hydrophysical conditions was carried out. In August 2017, hydrochemical indicators and zooplankton of 6 lakes were investigated: Namshi-Nur, Holbo-Nur, Gyzgi-Nur, Nuhu-Nur, nameless and Hara-Nur. It has been shown that when lakes dry and salinity increases, a decrease in the species diversity of zooplankton is noted. The main factors explaining 77.9% of the dispersion of numerical indicators of certain types of zooplankton in the lakes of the Tazheran steppe were salinity, the depth of the lakes, primary production, the content of organic substances, and the amount of dissolved oxygen. Different types of zooplankton respond to changes in each individual factor in different ways. When assessing the effect of a particular factor on zooplankton, it is necessary to take into account the limits of tolerance of individual species to the effects of each factor individually and to their combination.

Keywords: salt lakes, zooplankton, hydrochemical conditions, environmental factors, ecological optimums, Baikal region.

Financing. The work was carried out within the framework of the Project 134.1.2. of the program of the Federal Research Institute of State Academies «Spatial and temporal organization of aquatic ecosystems and assessment of the influence of natural and anthropogenic factors on the formation of hydrobiocenoses and the quality of surface waters».

DOI: 10.24412/1993-3916-2021-4-107-117

Yusupov A.R., Kurbanismailova A.S., Alkhulaev K.G., Mamaev A.S., Yusupov Z.A. THE INFLUENCE OF ANTHROPOGENIC FACTORS ON THE CHEMICAL COMPOSITION OF LAKES IN ARID REGIONS OF DAGESTAN (ON THE EXAMPLE OF THE GREAT AND SMALL TURALI) // Arid ecosystems. 2021. V.27. № 4 (89). P. 118-122.

Received March, 22 2021. After revision June, 30 2021. Accepted July, 01 2021.

Anthropogenic impact on the ecosystems of arid areas leads to environmental pollution. Assessment of the state of nature of arid regions is the most important task in the context of scientific and technological progress.

When studying the current state of the Turaly lakes, as representatives of reservoirs of arid conditions, various research methods were used. This made it possible to draw a conclusion about the level of pollution of objects and to assess the ecological condition of reservoirs characteristic of natural complexes of arid conditions.

Keywords: arid climate, ecology, anthropogenic influence, pollution, salinization, Turaly lakes.

Financing. The work was carried out on the topics of the Research Institute of the Russian Academy of Sciences: «Assessment and revision of the mineragenic potential of the North Caucasus on the basis of modern stratigraphic and lithological-geochemical methods of analysis of sedimentary complexes»(State registration No. AAAA19-119122690018-8) and «Ecological and geochemical features of groundwater in the North-Eastern Caucasus (Dagestan). Natural and anthropogenic pollution factors» (State Registration No. AAAAA 117-117021310203-3.

DOI: 10.24412/1993-3916-2021-4-118-122

Tashlykova N.A., Afonina E.Yu. PLANKTON DEVELOPMENT OF THE DIFFERENT LITORAL BIOTOPES IN SODA LAKES // Arid ecosystems. 2021. V.27. № 4 (89). P. 123-132.

Received May, 23 2021. After revision June, 30 2021. Accepted July, 01 2021

Water bodies with a naturally high level of salinity are geographically widespread. They are found not only in hot and arid regions, but also in some regions with temperate and cold climates, in particular in Eastern Siberia. Usually these are groups of closed lakes, the common features of which are their location in the semiarid climate zone, the absence of surface runoff, shallow depth, and a limited catchment area. They have significant variations in size and salinity. The article presents the results of studies of the structure of plankton communities and the relationship between environmental factors and the main characteristics of plankton in different littoral biotopes (overgrown and open littoral) of the soda lakes of the Onon-Borzya lake system.

Keywords: littoral biotopes, Onon-Borzya system, Bain-Tsagan Lake, Tsagan-Nor Lake, plankton, soda lakes.

Funding. This research was carried out within the state assignment of Institute of Natural Resources, Ecology and Cryology of the Siberian Branch of the Russian Academy of Sciences “Geology of Water Ecosystems of Transbaikalia under the Conditions of the Modern Climate and Technogenesis, the Main Approaches to the Rational Use of Waters and Their Biological Resources”, No. FUFR-2021-0006.

DOI: 10.24412/1993-3916-2021-4-123-132

Rudneva I.I., Shaida V.G., Scherba А.V., Zav’aylov A.V. CLIMATE EFFECTS ON THE ANNUAL AND SEASONAL DYNAMICS OF ECOLOGICAL STATE OF THE SALT LAKE ADJY-BAICHY (CRIMEA) // Arid ecosystems. 2021. V.27. № 4 (89). P. 133-142.

Received April, 15 2021. After revision June, 30 2021. Accepted July, 01 2021

Ecological state of the indoor water bodies, including hypersaline lakes are determined by the influence of the complex of the natural and anthropogenic factors. The aim of the present work was the annual and seasonal study of the monitoring of the hyprsaline lake Adjy-Baichy, which is located on the western part of Crimean Peninsula at the arid area. The fluctuations of the air and water temperature, hydrochemical parameters of the brine and Artemia salina population at the period of 2017-2020 were investigated. The common tendencies, characterized the air and water temperature increase in summer period, the highest values were found in July-September (<+30⁰ С), which was accompanied with the elevation of salinity and decrease of oxygen concentration.

Variations of pH and Eh were lower. The greatest salinity of the brine (< 350 ‰) was observed in 2017, the lowest value of oxygen concentration (0.7-1.0 мг/л,) was identified in 2020 and Eh (-78.5 мВ) were shown in 2019. Artemia cysts were found in all tested periods due the year, nauplii were found in March-April at water temperature +3+7⁰ С, the adults were caught in summer months and at the beginning of the autumn. In summer time at the high water temperature and low oxygen concentration the dead adults were found. The obtained results reflet the peculiarities of the effect of climate factors on the ecosystem of the hypersaline lake and they may be use as a model for the prediction of possible scenario of consequences of climate changes on the indoor water bodies and be useful for the understanding of the processes of transformation of aquatic ecosystems in arid areas and for the development of the programs for their protection and optimal management of their resources.

Keywords: hypersaline lakes, Crimea, seasonal fluctuations, temperature, hydrochemical characteristics, Artemia, drying out.

Financing. The work was carried out on the topic of the state task of the FGBUN IMBI «Functional, metabolic and toxicological aspects of the existence of hydrobionts and their populations in biotopes with different physico-chemical regime», state number. Registration AAAAA-A18-118021490093-4.

DOI: 10.24412/1993-3916-2021-4-133-142