Safronova I.N., Kalmykova O. G., Stepanova N. Yu. TRANSVOLGA-TRANSURAL STEPPES OF THE NORTHERN SUBZONE OF THE STEPPE ZONE: SPECIFIC FEATURES OF THE MODERN FORMATION DIVERSITY // Arid ecosystems. 2020. V. 26. № 4 (85). P. 4-9. | PDF
The significant part of the native Transvolga-Transural steppes of the northern subzone of the Steppe zone is destroyed by plowing. And on large territory they are represented by fallow lands of different age. It is known that communities of many formations are spread throughout the steppe zone. The differences in the structure of undisturbed communities in different subzones are quite clear. On fallow lands and pastures these differences are poorly visible. Basing on many years of our research of the vegetation cover in the steppe zone we aimed in 2018–2019 to find out how much the diversity of formations on the fallow lands changes and how their structure can be used to appreciate the subzonal status of the territory. The research is based on field studies including a route method, more than 100 geobotanical descriptions made by standard method, the analysis of which uses ecological-phytocoenotic classification; more than 700 herbarium sheets were collected. We revealed that zonal Stipa zallesskii steppes do not currently dominate in the Transvolga-Transural part of the Northern subzone, but Stipa capillata steppes are dominant representing the background vegetation on the fallow lands. Along with Stipa capillata steppes large areas are occupied by secondary Stipa lessingiana steppes. As peculiar component of the vegetation cover of the Northern subzone we can mention the communities of dwarf semishrubs. They are confined to saline soils or to the outputs of the rocks. Halophytic and petrophytic variants of steppes are represented not only by semi-shrub communities, but also by perennial grasses.
Ogureeva G.N., Bocharnikov M.V., Suslova E.G. STRUCTURE OF THE CRIMEAN-NOVOROSSIYSK OROBIOME (THE UTRISH-TUAPSE VARIANT) BOTANICAL DIVERSITY // Arid ecosystems. 2020. V. 26. № 4 (85). P. 10-17. | PDF
Based on the concept of ecosystem diversity, a regional assessment of the Crimean-Novorossiysk orobiome is given. Orobiome is considered to be a strong unit for inventory and analysis of mountain biodiversity. On the example of the Utrish-Tuapse geographical variant of the orobiome (the Northwest Caucasus), the altitudinal-belt structure of the vegetation cover is revealed, according to which the spatial differentiation of flora and plant communities are formed. A quantitative evaluation of biota and abiotic indicators characterizing the botanical and geographical traits of the orobiome is given. The spectrum of altitudinal zonality of vegetation is determined, a quantitative assessment of floristic diversity by the belt is given, and some features of the spatial structure of community diversity in mountainous areas are revealed.
Keywords: biodiversity, altitudinal zonation, orobiome, mapping, the Abrau Peninsula, Sub-Mediterranean.
Eremeeva E.A., Leonova N.B. FLORISTIC DIVERSITY OF ISLAND PINE FORESTS OF ZAVOLZHSKO-KAZAKHSTAN STEPPE PROVINCE // Arid ecosystems. 2020. V. 26. № 4 (85). P. 18-25. | PDF
Island pine forests of the Zavolzhsko-Kazakhstan steep province as the part of the Eurasian steppe region with their high biodiversity have relic genesis. Thus, their research and problems of conservation are urgent under increasing anthropogenic impact and climate changes. The complex analysis of floristic diversity based on the data of authors’ field surveys and scientific publications has been conducted for the pine forests of Karkaralinsky, Buzuluksky Bor and Burabay national parks, Naurzum reserve and Kanonersky forestry. The research also included study of the Ilmen Reserve and Burlinsky ribbon-like relict pine forest, located near the northern boundary of the province. For the first time the data on the floristic diversity of all large pine massifs of the province are summarized in a geographical aspect in a single key. The similarity in the taxonomic, geographical, ecological-morphological and ecological-coenotic structure of the floristic composition of all disconnected from each other island pine forests may be explained by their historical connections and relic nature. The results of the correlation and cluster analysis of floristic lists showed varying degrees of similarity between different pine massifs due to specifics of physical and geographical conditions. Three groups of pine forests have been distinguished: а) pine forests of sandy massifs in Naurzum reserve and Kannonersky forestry having xerophilous features, poor floristic diversity and prevailing steppe plants turfy cereals; b) pine forests of granite massifs of the Kazakh small hills (Burabay, Karkaralinskyсос national parks) with moderate species richness; c) pine forests of Buzuluksky and Burlinsky forests with high floristic richness of forest species having northernmost position in the province.
Keywords: island pine forests, steppe province, taxonomical and typological species diversity, ranges, ecological and coenotic species groups.
Lazareva V.G., Bananova V.A., Nguyen van Zung DYNAMICS OF MODERN PASTURE DIGRESSION ON THE QUATERNARY TERRACES OF THE NORTH-WESTERN CASPIAN REGION // Arid ecosystems. 2020. V. 26. № 4 (85). P. 26-34. | PDF
In this article we discuss the results of long-term researches of desertification (degradation) in the dry lands of the Northwest Caspian Basin. We consider the modern vegetation to be the result of pastures overload caused by cattle, and determined desertification as a process of unification which leads to decrease in species diversity in the plant communities and, therefore, unification of vegetation cover. The complex structure of soil and vegetation cover, common for Caspian Region, vanishes, and the native plant communities are replaced with groups of their transit derivatives. The quantitative evaluation of desertification includes stages (classes) of poaching, criteria of pasture digression and their indicators (plant communities). They determine the ecological and dynamical series of plant communities representing the process of degradation. Our research showed that out of all quaternary terraces the vegetation of the youngest one (New Caspian) is more vulnerable to degradation.
Keywords: Caspian quaternary terraces, pasture digression, indicators of pasture poaching, ecological and dynamical series of plant communities under desertification, unified vegetation.
Bazha S.N., Danzhalova E.V., Drobyshev Yu.I., Bogdanov E.A., Baskhaeva T.G., Rupyshev Yu.A., Ubugunova V.I., Tsyrempilov E.G., Ivanov L.A., Ivanova L.A., Migalina S.V., Khadbaatar S., Tserenkhand G., Shinekhuu T. ECO-BIOLOGICAL FEATURES FOR THE PRUNUS SIBIRICA L. DISTRIBUTION IN THE SOUTHERN PART OF THE SELENGA BASIN // Arid ecosystems. 2020. V. 26. № 4 (85). P. 35-45. | PDF
The article discusses the ways of the expansion of Siberian apricot (Prunus sibirica L.) in the southern part of the Selenga River Basin. On the south-western border of the boreal forests, there is a clear trend in the succession of pine forests to shrub vegetation represented by Siberian apricot communities. This is facilitated by the reduction of forested areas due to fires, felling and grazing, which in turn leads to a change in landscape and environmental conditions in forest ecotopes. In addition, the strengthening of the coenotic position of Prunus sibirica occurs due to its physiological and biochemical adaptation to the pyrogenic factor and eating by cattle, as well as the variability of the functional parameters of this species.
Keywords: Prunus sibirica L., Mongolia, forest-steppe, deforestation, bush encroachment, post-forest succession, functional characteristics of plants.
Shcherbakov A.V., Reier Ü., Grinchenko O.S. HOEFFT’S HERBARIUM FROM THE CAUCASUS // Arid ecosystems. 2020. V. 26. № 4 (85). P. 46-50. | PDF
In this article we present a history of F.A. Hoefft’s botanical works carried out in the North Caucasus, as well as places and amounts of his herbariums and how they made their way into various herbariums of Russia and Europe. It was determined that Hoefft’s herbarium of about 7000-8000 pieces, including its Caucasian part of 1800-2100 pieces, is a highly valuable botanical collection of the middle XIX century. Its importance is underestimated by the modern researchers due to the fact that by the beginning of the World War I many of those who studied Caucasian flora had left the University of Yuryev, and a quarter of the entire collection had been evacuated into the inner Russia to eventually come back only in the mid-1950s. It is highly recommended to resume the publication of “Flora Caucasica Critica” to introduce the Caucasian herbarium of F.A. Hoefft to the scientific circles again.
Keywords: F.A. Hoefft, flora of the North Caucasus, herbarium of the University of Tartu.
Karimova T.Yu., Lushchekina A.A., Neronov V.M., Pyurvenova N.Yu., Arylov Yu.N. BIOLOGICAL CHARACTERISTICS OF THE SAIGA POPULATION OF THE NORTHWEST PRECASPIAN REGION IN PERIODS DEPENDING ON THE VARIATIONS IN POPULATION SIZE // Arid ecosystems. 2020. V. 26. № 4 (85). P. 51-58. | PDF
The size of the population of the saiga (Saiga tatarica tatarica L., 1766) in the Northwest Precaspian region has remained extremely low over the past 20 years. Comparison of some biological parameters of the population in the periods characterized by different animal numbers revealed some features of the phase of population depression. Thus, apart from the decrease in the numbers of saigas (from 800 thousand in 1958 to 4.5 thousand in 2016), its habitat also decreased (from 60-70 thousand km2 to 2-3 thousand km2, respectively), and a significant part of the population switched to a sedentary lifestyle in the protected areas of the Chernye Zemli ecoregion. The shortage of mature males in the population (less than 10%) over a long time led to a reduction in its growth and, consequently, to a decrease in the numbers. At the same time, the total fertility of females decreased from 1.27 ± 0.25 in the years of high numbers to 0.92 ± 0.39 due to an increase in fertility in different age groups, which resulted from lack of males in the population. More males are born in the population than females (51.9% and 48.1%, respectively). The increased weight of newborn saigas (on average by 100 g in both males and females) and their decreased mortality in the first days after birth (under favorable weather conditions) indirectly indicate the normal process course of embryogenesis and sufficient quantity and quality of feed. An increase in the proportion of mature males will lead to an increase in the population size, reproductive functions of which remained virtually unchanged during its depression.
Key words: saiga, Northwest Caspian region, abundance, age and sex composition, reproductive indicators, spatial distribution.
Dzhapova V.V., Bembeeva O.G., Ayusheva E.Ch., Kazmin V.D., Dzhapova R.R., Abaturov B.D. FODDER SELECTIVITY OF SEMI-FREE BISON (BISON BISON) IN THE TURF-GRASS STEPPE OF THE WESTERN MANYCH VALLEY // Arid ecosystems. 2020. V. 26. № 4 (85). P. 59-65. | PDF
Materials about the composition of forage plants in the diet of bison were obtained during the summer and autumn seasons of 2018 in an aviary on the territory of the protected zone of the reserve «Rostov». The described territory is located in the sod-grass steppe of the Western Manych river valley. Data on the seasonal dynamics of the composition of forage plants in the bison diet were obtained by applying the method of cuticular microscopic analysis of excrements. For species identification of Botanical fragments from excreta, an electronic database of the reference cuticle structure of species that make up the floristic richness of bison pastures was created. In the summer diet of bison, the share of cereals is 64%, and in the autumn-84%. The selectivity index (SI) for grains was 2.1 in summer and 4.3 in the autumn, for forbs in summer – 0.5, and in the autumn has dropped to 0.2. The magnitude of the SI depends not only on the taste preferences of the animals, but also on the abundance of the species in the aboveground mass of grass pastures, and the phase of plant growth.
Keywords: diet composition, aboveground phytomass, selectivity of food.
Konyushkova M.V., Nukhimovskaya Yu.D., Gasanova Z.U., Stepanova N.Yu. VARIABILITY OF SOIL SALINITY AND PHYTODIVERSITY OF HETEROCHRONOUS REGIONS OF THE CASPIAN LITTORAL PLAIN // Arid ecosystems. 2020. V. 26. № 4 (85). P. 66-75. | PDF
The article discusses the results of soil and geobotanical studies at the plots on the coastal plain of the Caspian Sea (Northern Dagestan) of different ages: 1340 ± 36 years calBP (Kaspii-1) and 293 ± 13 years calBP (Kaspii-2). Changes in the biodiversity of the vegetation cover and the soil-salinity variation over time are assessed. It is shown that the variability of soil salinity (range, quartile scale, and standard deviation) at the local level (areas of nonuniformity with linear dimensions of meters or tens of meters) has increased, while the parameters of vegetation biodiversity (floristic richness, the species number, the families number, the number of long-vegetating herbaceous perennials and ephemers, the presence of species with different salinity tolerance, and differentiation of the intracoenotic diversity) have decreased. The plot with a Tamarisk community (Kaspii-2) is characterized by a statistically significant, moderate correlation (R2 = 0.29) between soil salinity and vegetation based on data on the distribution of dominant species, whereas this correlation is not significant on the older plot with a saltwort—suaeda community (Kaspii-1). The data show that, when the area dries up after sea regression, the variation in soil properties (salinity) and vegetation changes in different directions: the variation in soil salinity (functional pedodiversity) increases with age, while the variation in vegetation (phytodiversity) decreases. Moisture availability is obviously the main factor limiting the biodiversity on the older plot on the background of high salinization of soils on the both plots as evidenced with the smaller moisture reserve in the top 1-m soil layer on the older plot.
Zolotokrylin A.N., Titkova T.B., Cherenkova E.A. CHARACTERISTICS OF THE SPRING-SUMMER DROUGHTS DURING THE DRY AND WET PERIODS IN THE SOUTH OF EUROPEAN RUSSIA // Arid ecosystems. 2020. V. 26. № 4 (85). P. 76-83. | PDF
Distribution patterns of spring and summer droughts characteristics during high and low annual humidification periods are studied in twelve federal subjects of the South of European Russia for the period 1901-2018. During this time, four periods of different humidification conditions (alternate more humid, dry, humid and again dry periods) with variable durations are observed through data on anomalies of the aridity index in seven regions: Kursk, Belgorod, Voronezh, Saratov, Volgograd, Rostov Oblasts and the Republic of Kalmykia. The draining period was noted in Samara and Astrakhan Oblasts from the beginning of 20th century until its middle. Then the draining period changed to more humid. The most frequent change of periods with different humidification conditions was observed in Stavropol Krai, where five alternate periods were distinguished. It was found that the frequency of spring and summer droughts is consistent with the long-period humidification conditions. According to data of the Standardized Precipitation Index (SPI), it increases during the dry period by an average of 1.5 times while the intensity of droughts rises insignificantly. The increased humidification conditions observed in every above-mentioned federal subject in the second half of the 20thcentury changed to drier conditions in the beginning of the 21st century. The spreading of drier conditions began from east regions. The development of the dry period of humidification in the 21st century is confirmed by a distribution of a negative NDVI trend throughout the territory. While the aridization trends are not statistically significant in the regions of the South of European Russia in more than a century, there are prolonged interdecadal periods of aridizational strengthening and weakening, which are characterized by significant differences in frequency and intensity of spring and summer droughts.