Northwestern Caspian Region Research Articles

The Food Resource Status and Nutrition Selectivity in the Midday Gerbil (Meriones meridianus) in Arid Conditions of the Northwestern Caspian Region

The Food Resource Status and Nutrition Selectivity in the Midday Gerbil (Meriones meridianus) in Arid Conditions of the Northwestern Caspian Region

РОЛЬ ИЗМЕНЕНИЙ АТМОСФЕРНОЙ ЦИРКУЛЯЦИИ В УВЕЛИЧЕНИИ ПОВТОРЯЕМОСТИ ЛЕТНИХ ЗАСУХ НА ЕВРОПЕЙСКОЙ ЧАСТИ РОССИИ

According to the Standardized Precipitation Evapotranspiration Index (SPEI), most extensive summer droughts in European Russia south of 55°N in 1950-2021 were observed during the extremely negative phases of the Eastern Atlantic/Western Russia (EAWR) and West Pacific (WP) atmospheric circulation patterns characterized by abnormal high atmospheric pressure and an increased frequency of the number of days with atmospheric blocking over European Russia. It is shown that the frequency of droughts in the study area in the years of the negative phases of both circulation indices and their extremes in the summer months as compared to other years was higher by five droughts per decade in the Volga and Central Chernozem regions and by three droughts per decade in the northwestern Caspian region. A statistically significant correlation was found between the EAWR in summer and the multidecadal variability of sea surface temperature in the North Atlantic. It was revealed that the increase in the drought frequency in the study area in recent decades has been caused by the restructuring of atmospheric circulation in the Euro-Atlantic sector accompanying the transition of the Atlantic Multidecadal Oscillation (AMO) to a positive phase. An increase in the stability of the EAWR and WP atmospheric circulation patterns was observed, as well as a related significant increase in the frequency of extensive droughts in the study area in 2010-2021. They were accompanied by the weakening of zonal atmospheric circulation in the Northern Hemisphere, the combination of the positive AMO phase and the effects of anthropogenic warming on the atmospheric circulation in the

The Nitrogen Balance in the Soil–Plant Cover of Arid Ecosystems in the Northwestern Caspian Region

The Nitrogen Balance in the Soil–Plant Cover of Arid Ecosystems in the Northwestern Caspian Region

The Map of the Current Vegetation on the Territory of Distribution of the Population of Saiga tatarica tatarica L. in the North-Western Caspian Region

The Map of the Current Vegetation on the Territory of Distribution of the Population of Saiga tatarica tatarica L. in the North-Western Caspian Region

Plant Community Transformations in Desert Rangeland Ecosystems – Evidence from the North-Western Caspian Lowland

Abstract—The article presents the results of long-term monitoring of successions, and the production dynamics in desert rangeland phytocoenoses over an 8-year period (2014–2021). It shows the current state of vegetative cover of the Chernozemelskaya sandy plain (north-west of the Caspian lowland, Republic of Kalmykia) following forest reclamation of fine-grained sands, carried out in the 1970s–1990s. The centers of soil deflation (aeolian erosion) differed by the degree of soil and vegetative cover transformation and the methods of the reclamation of open sands. Currently, a secondary vegetative cover has been formed on the previously identified deflation patches. The expansion and evolution of the current species composition suggests the development of secondary succession. The features of the synusial structure of desert phytocenoses reflect the state of plant communities. The relationship of the productivity of model pastures (shrub Callygonum aphyllum, subshrub Krascheninnikovia ceratoides, herbaceous species Stipa lessingiana, Artemisia lerchiana, Alyssum deserforum, Bromus tectorum, Carex stenophylla, Koeleria macrantha, Poa bulbosa) with precipitation in warm and cold periods of the growing season is analyzed. Under changing temporal and spatial climate dynamics, the successional processes are greatly influenced by wildfires and anthropogenic impact. It has been established that secondary successions under heavy transformation of the agro-pasture landscape develop more slowly. Thus, the natural and landscape environment of the current deflation centres in the rangelands of the North-Western Caspian region is an important factor determining the direction of succession.

Ecological potential of pasture ecosystems of desolate steppes in the conservation of the saiga population of the NorthWestern Caspian Sea

The destruction of natural ecosystem resulting in reduction or even destruction of saiga habitat is the consequence of anthropogenic impact. The degradation of pasture ecosystem in Kalmykia reached a crucial level and the republic was announced as the disaster zone in 1988. The year 1998 witnessed the reduction of saiga population size from 220 thousand to 55 thousand animals. Registration works in 2014 showed further reduction of saiga to 12 thousand- 12.8 thousand animals. In general, the population of saiga in the North-Western Caspian region continues to be in depression despite low losses of new born saiga (6.2%). The degradation of pastures led to the next stage of population cycle characterized by lower reproduction ability of animals and high level of mortality. This process deteriorates due to worse living conditions during some seasons as well as by decreasing the ability of pastures to give feed.

Современная парадигма экологической устойчивости агроландшафтов и эффективного использования земель Прикаспийской низменности

The relevance and practical significance of the research was due to the fact that in the North-Western Caspian region, in recent decades, due to natural and anthropogenic factors, a generally unfavorable environmental and socio-economic situation has developed. Despite the existing theoretical and practical developments of rational nature management in the Caspian region, some scientific provisions and zonal recommendations for the efficient use of agricultural land require a new understanding. The results of scientific research and the accumulated production experience convince us that in the system of adaptive agriculture in arid regions, it is necessary, first of all, to scientifically substantiate the selection of the most drought-resistant and highly productive crops that use the natural resource potential efficiently. The basis of the economy of the Republic of Kalmykia, as an agrarian subject of the Russian Federation, is agriculture with a highly developed animal husbandry with a specialization in beef cattle breeding and fine-wool sheep breeding. Further successful development of the agrarian sector of the economy in the context of an increasingly arid climate and the positioning of the republic as a promising region of Russia for the production of high-quality beef is only possible with the creation of a solid forage base on natural lands and arable lands. In the difficult ecological and economic conditions of the North-Western Caspian, one of the most acute problems is the increasing processes of land desertification, the preservation and reproduction of the fertility of zonal low-humus soil subtypes. For the successful functioning of the agro-industrial complex of Kalmykia, a comprehensive optimization of the water supply of the rural population, pasture animal husbandry and irrigated agriculture is necessary. A necessary condition for the successful development of agriculture in the region in the future is also a more complete information supply of domestic farmers with information about current trends in science and best practices, and the introduction of innovative research.

Migration of Peasants to Landowners' Lands in the North-Western Caspian Region (the second half of the XVIII – first half of the XIX century)

Migration of Peasants to Landowners' Lands in the North-Western Caspian Region (the second half of the XVIII – first half of the XIX century)

State Power and Fishing Settlements on the Lands of Nomads in the North-Western Caspian Region (the second half of the XVIII – XIX centuries)

State Power and Fishing Settlements on the Lands of Nomads in the North-Western Caspian Region (the second half of the XVIII – XIX centuries)

Rooting capacity of grape cuttings in the north-western caspian region

Experience in studying the rootability of grape cuttings was conducted on the territory of the vineyard of the Precaspian agrarian federal scientific center of the Russian academy of sciences, located in the Chernoyarsky district of the Astrakhan region. The research period is from 2015 to 2019. The relevance of the research is due to the insufficient availability of local planting material in the regions of the Russian Federation, as well as the high efficiency of the method for obtaining grape seedlings on their own roots. The purpose of the research was to study the survival rate of grape cuttings in the crop and identify varieties that are characterized by the best rooting ability. The article presents data on the ability to root cuttings of grapes of 18 table varieties of different maturation periods. The lowest rooting rate in the experiment had varieties Cardinal, Straseni, Memory Negros, the Gift to Zaporozhye, Karaburnu. It was found that the use of early – maturing varieties Kodryanka, Bogatyrsky, Lora, middle – matured-Husain pink and Lowland, late-matured-Moscow, Sevan, Soviet, the level of rootability of which varied from 44.2 to 71.4 %, is optimal for obtaining root-related seedlings of grapes.These varieties have a good ability to rhizogenesis, which allows us to recommend them for accelerated propagation of grape varieties.

История древесно-кустарниковых сообществ крупнейшего байрачно-балочного местообитания Заволжья

История древесно-кустарниковых сообществ крупнейшего байрачно-балочного местообитания Заволжья

FEATURES OF ALKALOID ACCUMULATION IN MEDICINAL PLANTS DUE TO GROWING CONDITIONS AND AGE CHARACTERISTICS

Nowadays biologically active substances in medicinal plants of Kalmykia are poorly studied. Thus biochemical properties of medicinal plants of the arid territories of the North-Western Caspian region have been studied for the first time. Study of intraspecific variability allowed to determine the influence of growing conditions on the accumulation of biologically active substances and microelements in medicinal plants, that grow in Kalmykia. In this regard, as the alkaloid, flavonoid and tannin content has been shown, approaches of application of known medicinal plants and searching for new raw materials should be reconsidered. This work is a part of comprehensive resource investigation focused on the research in the aim to find rational application of plant growing in Caspian and Volga regions. On the natural forage lands of Kalmykia, alkaloid-bearing plants can be found; they are poisonous to animals, and their number and abundance are directly dependent on anthropogenic pressure. Anabasis, harmalа and ephedra, that grow on the Caspian lowland, contain all groups of studied substances: alkaloids, flavonoids, tannins and extractives. The conducted research shows that alkaloid plants might be used as medicinal plant raw materials. In Anabasis, the total alkaloid content reaches 1.26% in summer and 1.44% in autumn. Percentage of peganin in Harmala grass, stem and root, is about 4.04%, 0.31% and 0.21% respectively while the total amount of alkaloids in harmala exceeds 5.0%. Tannin content is quite high in Anabasis and harmala, as the presence of tannins is a characteristic feature of ephemera. The composition of plant extractives includes all water-soluble biologically active substances: carbohydrates, vitamins, flavonoids, etc., content of the chemicals is high in both Anabasis and harmal. Accumulation occurs even regardless of the season, place of growth in the whole plant.

Increasing the Efficiency of Plant-Cover Restoration in the Modern Focus of Deflation on Pastures of the Northwestern Caspian Region

The change in the use of forage lands in the Black Lands and the Kizlyar pastures of the Caspian Sea region in the second half of the 20th century from winter to year-round, their overload with livestock, and plowing for forage crops led to the degradation of natural ecosystems, an outbreak of light-soil deflation, and the formation of large foci (with an area of ​​hundreds or thousands of hectares) of fine sands. The development of new technologies and the implementation of large-scale studies on their phytomelioration in the 1970–1990s made it possible to restore the vegetation cover on an area of ​​over 400 000 hectares and to stop the avalanche-like desertification of lands. However, the productivity and nutritional benefits of secondary phytocenoses obtained large differences. The article reveals the morphoecological specificity of the development and the water-physical properties of the soil of modern deflation foci. The technologies of their shrub and complex phytomelioration are considered. The formation features, biological diversity, productivity, and stability of the secondary vegetation cover were determined based on materials from the long-term monitoring of successions. The advantages of complex phytomelioration, including the use of woody, semishrub, and herbaceous plants, have been found. It was found that the created regenerative fodder ecosystems produce 2.0–5.0 t/ha of hay in the first 5–10 years and develop according to the shrub–herb type. Their floristic composition expands to 30–50 species in the subsequent decades. Their productivity decreases to 1.0–2.0 t/ha but depends less on the amount of precipitation than in virgin areas. Forage (up to 55%) and medicinal (up to 12%) plant species prevail in the 20- to 30-year-old phytocenoses. Pamirian winterfat has a high coenosis potential and stability. Pastures with its participation are distinguished by the stability of the pasture stock in terms of the composition and years of observation. At the same time, the indigenous species of valuable pasture plants (forage kochia, wormwood, and perennial grasses) slowly penetrate the cover of “extinct” deflation foci. It is necessary to improve the methods of their primary phytomelioration and to reconstruct a low-value vegetation cover on fixed sands. Measures to improve the technologies of primary phytomelioration of modern foci of deflation should be based on the expansion of the range and the joint use of valuable forage shrubs and perennial psammophilic grasses, the effective protection of local regenerative forage phytocenoses from sand transfer, the creation of a shady tree layer, the organization of moderate grazing of the secondary cover in subsequent years, and stimulation of the spread of indigenous grazing plant species.

ВОЗМОЖНОСТИ ЛАНДШАФТНОЙ АРХЕОЛОГИИ В ИЗУЧЕНИИ ЛОКАЛЬНОЙ МОБИЛЬНОСТИ СТЕПНЫХ СКОТОВОДЧЕСКИХ КУЛЬТУР ЭПОХИ ПАЛЕОМЕТАЛЛА

The article is devoted to testing the effectiveness of methods of cultural landscape archaeology for studying the local mobility of steppe pastoral cultures of the Paleometal Epoch (Eneolithic — Bronze Age) of Central Eurasia. In the paradigm of landscape archaeology comprehensive studies of a series of reference polygons have been recently carried out in the North-Western Caspian region, the Middle Don region, the Southern Trans-Urals, the Ural-Mugodzhary region. The research protocol included the use of GIS technologies, means of shallow-depth geophysics, geoarchaeology, archaeobotany, archaeozoology, paleoanthropology, paleosurface science, paleoclimatology, the study of isotope archives, etc. As a result, it was found that the life support system in the reconstructed economic and cultural models was based on various forms of mobile cattle breeding with seasonal rotation of pastures and water sources with a subsidiary role of hunting and gathering. In areas where copper ore sources were located, they were harmoniously combined with mining and metallurgical production due to the coincidence of seasonal economic and production cycles. This economic system allowed achieving a dynamic balance between human needs and the natural resource potential of the developed steppe and mountain-steppe geosystems, relying on their ability to regenerate without losing their ecological function. The research has shown that landscape archaeology can claim to be a methodological basis for studying local mobility of steppe pastoralists of the Paleometal Epoch. At the same time, none of its the methods, including the most effective isotope studies, can claim to be universal. Only a comprehensive application of the entire arsenal of landscape archaeology methods can lead to the reconstruction of economic and cultural models based on mobile forms of cattle breeding.

Craniology and archeology of the east manych catacomb culture - perspectives of the analysis of the consistency of signs

This thesis demonstrates results of a comparison of new published craniological data of the East Manych catacomb culture population (Middle Bronze Age, North-Western Caspian region), of the funeral rites and the artifacts’ assortments in the burials of this culture and the types of decoration of incense burners - the special ceramic vessel. At least the more frequent appearance of incense burners in burials of individuals with an artificial deformation of the head (both men and women) is detected. Any other combinations of craniological and archaeological features are doubtful. The comparison of incense burners’s decoration and attributes funeral rite demonstrates the correlation of point type of décor and more frequent use of bronze knives and piercers.

Mass Migration of Social Voles (Microtus socialis Pallas, 1773) in the Northwestern Caspian Region

A considerable increase in the social vole population distributed in the northwestern Caspian region (Republic of Kalmykia) in 2014–2016 has been recorded. The average long-term dominance index of the rodent cenosis in 2014–2016 was three times as high as in 2002–2010. The rise in the rodent population was caused by an increase in the reproduction rate due to adequate fodder supplies under favorable climatic conditions. In May 2016, social vole mass migration and deaths were registered; it is a rare phenomenon arising in rodents that may be caused by overdensity of their population. All of the males were first involved in the migration process because of increased intraspecific competition, higher aggression levels, and weaker attachment to the habitats as compared to the females. The mass migration and deaths of social voles in the northwestern Caspian region may reflect the unstable equilibrium dynamics caused by changes in the anthropogenic pressure and land-use system, which interacts with the damping effects in the climate.

Breeding salt-tolerant cultivar of a halophytic annual Suaeda altissima L. in the Caspian semidesert

The aim of the study was to breed a salt-tolerant cultivar of annual forage halophyte Suaeda altissima L. under irrigation with 8–10 g L–1 saline waters. The field trials took place at the Astrakhan Experimental Reclamation Station on light-chestnut soil. The breeding stock was formed of 19 samples collected from the saline soil of the Astrakhan and the Volgograd oblasts, Stavropol krai, and the Republic of Kalmykia as well as in Uzbekistan and Turkmenistan. Promising Suaeda altissima L. specimens were selected from a collection of different ecological and geographical populations and were evaluated by their salt tolerance and forage and seed productivity. They were assessed in a competitive variety trial for a complex of biological, ecological, and commercially valuable traits. Finally, a promising specimen K-227 (the Volga region of the Astrakhan oblast) was selected, resulting in a new cultivar Zemfira enlisted into State Breeding Register. The cultivar yields 12 t ha–1 dry mass and 8 dt ha–1 seeds under saline water irrigation in the Northwestern Caspian Region.

Pollen evidence for Late Pliocene – Early Pleistocene vegetation and climate change in the North Caucasus, North-Western Caspian Region

Pollen and spores have been analysed in deposits of the Akchagylian–Apsheronian in the north-western Caspian Sea region, providing a picture of past vegetation and climate change for the late Pliocene to early Pleistocene. On the basis of pollen assemblages in sediment cores and outcrops from the North Caucasus (the Caucasus Mineral'nyye Vody region, the Tersko-Sunzhensky area and the foothills of Dagestan), climatic fluctuations, and related changes in vegetation can be recognized for the time from 3.6 to 0.8 Ma. The lower Akchagylian is characterized at first by an open landscape dominated by steppe vegetation. In the middle of the lower Akchagylian, the transgression of the palaeo-Caspian spread, and the treeless landscapes of the earliest Akchagylian were replaced by forests with thermophilic relicts. During the middle-upper Akchagylian and Apsheronian periods, the vegetation cover of the North Caucasus gradually changed: forests were replaced with steppe and semi-desert vegetation in response to episodes of aridification, and changes were evident in the structure of the dendroflora. The vegetation of the North Caucasus shows changes consistent with climatic warming at around 3.2 Ma which coincides with a period of warming in the Mediterranean and probable represents the “Mid Pliocene Warm Period”.

Satellite climate extremes index of drylands

A satellite index for detecting climate extremes, such as droughts and overhumification after heavy precipitation in drylands has been suggested, i.e., a Satellite Climate Extremes Index. The Satellite Climate Extremes Index represents summed deviations from the long-term average values of the albedo, the surface temperature, the soil moisture and the Normalized Difference Vegetation Index normalized to standard deviation. The properties of using this index to study the desertification dynamics based on the example of the northwestern Caspian region are discussed.

NATURAL AND ANTHROPOGENIC MECHANISMS OF IMPACT ON PASTURES PLANT COMMUNITIES IN THE NORTH-WESTERN CASPIAN REGION

The data from field studies on the influence of anthropogenic and ecological mechanisms on the species of forage plants of natural pasture phytocenoses is presented in the article. An explanation for the development of vegetation change processes in phytocenoses under existing conditions is given. The influence on the change in the structure of vegetation, the processes of transformation of communities has been studied. A noticeable decrease in the productivity of phytocenoses was shown at an unstandardized load of 3-4 sheep per hectare.Studies have established the negative influence of external mechanisms on the preservation of valuable forage grasses, depending on the different modes of use of pastures in the North-Western Caspian region. A noticeable decrease in the dynamics of productivity of phytocenoses with an increased load in the range of 4.54-2.27 centners / ha in the spring is shown. The results of the conducted studies show that the peculiarities of changes in the vegetation cover are mainly determined by the formation of an anthropogenic landscape with the domination of the most resistant xerophyte dwarf shrubs and the replacement of indigenous species of the community with unsuitable plant species for food that are formed in a continental climate. Changes in the composition of the vegetation cover, the ratio of species of forage grasses with different adaptive strategies were studied. Found significant changes in the vegetation cover in the experimental plots with non-standardized load. The grass stand is sparse, with a low projective cover of 32-67%. In places of failure, one- and two-year-old plants grow with some poorly eaten perennials; loss of unstable species, especially cereals, is observed. Areas of phytocenoses with a moderate load were characterized by an average of 72% projective cover due to the content of the proportion of grasses, forbs and xerophytes with a high level of adaptation and resistance to various mechanisms of influence.