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DESERTIFICATION OF THE AMU DARYA DELTA AND VEGETATION DYNAMICS DURING ARAL CRISIS

Arid Ecosystems

UDC 581.5

Novikova N.M., Kuzmina Zh.V., Mamutov N.K.DESERTIFICATION OF THE AMU DARYA DELTA AND VEGETATION DYNAMICS DURING ARAL CRISIS // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 4-20. | PDF

The study is devoted to dynamics of ecosystems and their components in connection with the development of the Aral ecological crisis. The theoretical basis of the work was the idea that vegetation dynamics under desertification of the delta landscape is caused by anthropogenically influenced natural hologenetic process of vegetation change from hydromorphic floodplain and floodplain biotopes to semi-hydromorphic meadow and saltmarsh biotopes, which ultimately leads to the formation of zonal vegetation of automorphic biotopes. These are endo-ecogenetic shifts caused by a directed reduction in the moisture availability of biotopes and the accompanying salinization and evolution of soils. Shifts occur both successively and catastrophically. In the northern unused part of the Amu Darya Delta, due to the reduction of the water surface of the sea and a sharp reduction in water availability by the 1990s, environmental conditions inherent to desert landscapes have developed: the values and regime of climatic parameters approached the desert, groundwater was buried  to the depth of 5-10 m and became inaccessible to plant roots. The reconstruction of the system of reservoirs and the filling of former sea bays contribute to the formation of hydromorphic conditions in local areas.

Geobotanical studies initiated in 1979 in the Amu Darya Delta using  route observations and  topo-ecological profiles crossing the main elements of the delta relief (riverine ramparts, their slopes and inter-river depressions) were repeated in monitoring mode in 1985, 1993 and 1999. Route observations conducted in 2017 showed that the modern period of vegetation dynamics is the formation of desert-type plant communities. On most of the territory of the undeveloped delta, which turned into a wasteland after the death of reed (Phragmites australis (Cav.) Trin. ex Steud.) communities (1970-1980), there is an active settlement of the black saxaul (Haloxylon aphyllum (Minkw.) Iljin), encountered for the first time in the Muynak district in 1993. The desert species teresken gray (Krasheninnikovia ceratoides (L.) Gueldenst.), which settled around the same years in the degrading tugai and sparse monocenoses of the tree-like salsola (Salsola dendroides Pall.) on the salt marshes, formed extensive thickets to the north of Kungrad.

Observations on topo-ecological helped to describe trends of particular shifts and stages more detailed. On the right bank of the Akdarya channel, feeding the Mezhdurechensk reservoir, on the topo-ecological profile of Porlytau, 3 km southwest of the hill of the same name, for almost 40 years of observations, the river washed away a section of the riverbed floodplain and the riverbed shaft 500 m wide and eroded 9 m of banks – the level of the eastern part of the Big Sea – fell by 26 m. Vegetation changes are slowly developed. The succession is as follows: from woody sucker-poplar taut (Populus ariana+Populus pruinosa+Elaeagnus angustifolia-Mixteherbosa) through shrubby with tamarix multi-branched (Tamarix ramosissima Ledeb.) and finally to catastrophic change in the nearby site of the interrustal depression – the death of the karabarak (Halostachys belangeriana (Moq.) Botsch.) community. This plant community was formed in 1985 as a result of salinization of the soil on the site of dead reeds. In 2017 the process of slow surface soil desalination which began in 1993 continued in all points of the profile by the irradiation of salts from the upper horizons (0-10 cm) to the lower ones. On the outskirts of Tugai in 2017, for the first time, the presence of a desert species of teresken gray was noted, which possibly will settle throughout this area.

In the north-east of the delta, on the topo-ecological profile of the Kunyadarya, starting on the right bank of the dry channel of the same name and descending in a south-easterly direction to the coastal plain, the degrading Chingil-turang tugai on the riverbed shaft is replaced by tamarix, as evidenced by the species composition of the described community Populus diversifolia-Tamarix laxa+Halimodendron halodendron+ T. ramosissima-Atriplex tatarica. In the community of tall, well-developed tamarix and salt plants located further along the profile on the slope of the riverbed shaft, a black saxaul was first detected in 2017. Then the profile goes to the coastal salt flat Halostachys belangeriana-Climacoptera aralensis community. The salt profiles of soils under all plant communities have similarities : the maximum salt content falls on the upper part of the profile 0-10 cm, it sharply decreases in the horizon 10-20 cm and further to a depth of 50 cm remains unchanged. The salt profiles of the soils under the two sections of the tugai have the greatest similarity. The uppermost horizon of 0-5 cm is less saline or somewhat washed from salts than the deeper horizon of 5-10 cm with the maximum salt content. In the community of Karabarak, the maximum salt content (8.28%) is in the surface horizon of the soil 0-5 cm and sharply decreases to the horizon of 10-20 cm to 2% and decreases to almost 1%. The salt profile under the tamarix communities differs from the rest in that it is all slightly saline and has two maxima – surface weak salinity (0-5 cm – 0.5%) and average salinity (0.8%) at a depth of 20-30 cm. The salt profiles of soils on the topo-ecological profile of Kunyadarya indicate progressive salinization of soils with a pronounced surface-accumulative profile under the influence of pulsating secondary hydromorphism of this site, provoked by the periodically appearing flow of water from the Gulf of Dzhiltyrbas towards the sea.

In 2017 a newly formed young tree tugai was described in a small area on the bank of the irrigation canal crossing the degraded tugai Yerkin. It differs from the degraded ones described earlier : its full–fledged structure has 3 levels, and the richness of the species composition of plants consists of 12 species. Two types of lianas, undergrowth and renewal of woody dominant species of the community are noted. The soil under the young tugai is alluvial-meadow-tugai (hydromorphic), slightly saline (0.36%) only in the near-surface horizon of 0-5 cm.

Comparison of the data obtained on topo-ecological profiles with the data of previous observations, allowed us to assume that the change of plant communities in the conditions of desertification of the unused part of the delta in the communities of woody tugai is mainly successional. At the same time grass and shrub communities, especially their halophilic variants, are changing catastrophically. After they disappear  non-overgrown wastelands are formed for a long time. Conditions for the introduction of species with opposite ecology are prepared.

In local hydromorphic conditions with the floodplain water regime the formation and existence of tugai-type plant communities is possible. As a result the diversity of environmental conditions were characterize and modern processes occurring in the vegetation and landscapes of the unused part of the Amu Darya Delta are detected. These results are useful for organizing and conducting of natural resources use and biodiversity conservation.

Keywords: Uzbekistan, the Republic of Karakalpakstan, used and unused lands of the Amu Darya delta, desertification, hydromorphic, semi-hydromorphic, automorphic stages, topo-ecological profiles, observations, hologenesis, endo-ecogenetic successions, catastrophic and successional changes of vegetation, salt profile of soils, salinization and desalination of soils.

Acknowledgements. Auhors are grateful to M.V. Konyushkova, PhD in Agricultural Sciences, for her assistance in organizing and conducting field work in 2017, processing and analyzing soil data.

Funding. The expedition work was carried out with the financial support of the Regional Representative Office of the International Center for Agricultural Research in Arid Regions – ICARDA, Tashkent (project manager K. Toderich), the analysis of materials and the writing of the article was carried out within the framework of the topic no. FMWZ-2022-0002 of the state task of the Institute of Water Problems of the Russian Academy of Sciences «Research of geoecological processes in hydrological systems of land, formation of surface and groundwater quality, problems of water resources management and water use in the conditions of climate change and anthropogenic impacts».

DOI: 10.24412/1993-3916-2023-4-4-20

EDN: BXJHWA

FLORA OF COMMUNITIES INVOLVING PALIURUS SPINA-CRISTI MILL. FOOTHILL DAGESTAN

Arid Ecosystems

UDC 581.93 (470.67)

Sadykova G.A. FLORA OF COMMUNITIES INVOLVING PALIURUS SPINA-CRISTI MILL. FOOTHILL DAGESTAN // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 21-29. | PDF

The results of the analysis of the flora of the paliurus communities of Piedmont Dagestan are presented, ranging from the extreme southern (spurs of the Main Caucasian Range, near the village of Novoe Karakyure) to the extreme northern point of growth on the border with the Chechen Republic (Kizilyurt district, outskirts of the villages of Mutsal-aul and Gadari). The maximum assessment of the diversity of plant communities was carried out on the basis of data from 17 geobotanical descriptions.

A taxonomic analysis of the flora was carried out, and a spectrum of leading families was identified that belongs to the Po-As-La + Fa spectrum, characteristic of the Central Asian type with a significant influence of the Mediterranean flora. According to the results of biomorphological analysis, the predominance of hemicryptophytes (45.4%) and therophytes (33%) was revealed. The latter are an indicator of the aridity of conditions and anthropogenic impacts on coenoses. Geographical analysis, which revealed the predominance of species of the boreal (30.4%) and ancient Mediterranean (27%) types, showed its border position at the junction of the boreal and xerophilic types, reflecting the development of flora characteristic of the Caucasus in the contact zone of the Euro-Siberian and Iranian-Turanian regions with subsequent penetration of the Near Asian flora.

Based on the results of floristic studies, an assumption was put forward about the primary of communities of foothill paliurus of Dagestan due to the centuries-long stability (5-6 thousand years) of the geoclimatic conditions of the territory, the xerophytic composition of species of the shrub layer, and the absence or single participation of Querсus species in the group of associations Paliureta graminosa, the association Paliuretum ( Tarki-Tau, near the city of Makhachkala) and a group of ass. Paliureta bryosa, ass. Paliuretum bryosum (Beyukdere Ridge, Tabasaran District).

In the foothills of Dagestan, the occurrence of single individuals of the species Quercus and Ulmus campestris in the composition of paliurus rare forests, in our opinion, is not a synusial remnant of oak forests. Communities with Paliurus spina-christi grow here on the lower belt of mountain slopes, bordering oak forests, and are the result of an ecotone effect, in which, in some optimal ecological microniches, accidentally introduced oak specimens can grow together with P. spina-christi. At the same time, the boundaries of the forest, as well as the altitudinal levels of the ecotone areas, depend on the steepness and solarity of the slopes. In a broader spatial and temporal aspect, in Piedmont Dagestan, the shift along the altitudinal level of the boundaries of paliurus and forests with the dominance of Quercus and Ulmus campestris species depends on changes in the climatic tendencies of its aridization or humidization.

Keywords: Paliurus spina-cristi; Piedmont Dagestan; flora analysis; primary communities; successions, arid woodlands.

Funding. The work was carried out within the state specification No. 122032300227-8 «Geoclimatic features of distribution and description of communities with populations of rare and resource tree species of the North Caucasus».

DOI: 10.24412/1993-3916-2023-4-21-29

EDN: DLKUAL

IS THERE UPLAND XEROPHITES IN THE MOUNTAINS OF SOUTH SIBERIA?

Arid Ecosystems

UDC 574.42; 574.9

Volkov I.V., Volkova I.I. IS THERE UPLAND XEROPHITES IN THE MOUNTAINS OF SOUTH SIBERIA? // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 30-37. | PDF

In the most arid sector of the Altai Mountains (Russia), the Southeastern Altai, the pattern of biomorphological, ecological and species differentiation of phytocoenoses makes it possible to observe a tendency towards the local formation of a type of arid zonality сlass, characteristic of the arid mountains of Middle Asia, and includes following belts (bottom to top): 1) shrub deserts; 2) communities of thorny cushion plants; 3) alpine steppes; 4) communities of cryophyte cushion plants. Relatively wide distribution (where there is enough mountain height) of this «full-term» type zonality, including belts of thorny cushion plant communities and cryophyte cushion plant communities, makes it necessary to revise the traditional botanical-geographical concepts towards a greater diversity of higher syntaxa of vegetation and orobiomes both in the territory of the Southeastern Altai and in the mountains of the Southern Siberia as a whole.

Keywords: deserts, upland xerophytes, communities of Oxytropis tragacanthoides, communities of cryophyte cushion plants, altitudinal zonation, Southeast Altai.

Funding. The research was carried out on the equipment of a Unique scientific device «System of experimental bases located along the latitudinal gradient» of TSU with the financial support of the Ministry of Education and Science of Russia (RF-2296.61321X0043, 13.UNU.21.0005, Contract No. 075-15-2021-672) and with the support of the Tomsk State University Development Program («Priority-2030»), project No. 2.2.2.22 ONG.

DOI: 10.24412/1993-3916-2023-4-30-37

EDN: EVEVTY

THE DIVERSITY AND DYNAMICS OF AGROSTEPS VEGETATION IN THE EUROPEAN PART OF RUSSIA (ON THE EXAMPLE OF KULIKOV FIELD, TULA REGION)

Arid Ecosystems

UDC 581.524.31; 581.55; 502.2.05; 504.052

Volkova E.M., Polyancheva S.A.,  Rozova I.V. THE DIVERSITY AND DYNAMICS OF AGROSTEPS VEGETATION IN THE EUROPEAN PART OF RUSSIA (ON THE EXAMPLE OF KULIKOV FIELD, TULA REGION) // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 38-47. | PDF

The restoration of disturbed ecosystems is an urgent scientific problem, the solution of which will preserve the biological diversity of Russian regions. For the restoration of steppe ecosystems on the territory of Kulikovo Field, various methods and approaches have been used over the past 20 years. It allowed to form the agrosteps of different ages. However, the diversity of their vegetation has not been assessed. The purpose of this work is to identify the cenotic diversity of agrostep vegetation based on the ecological–phytocenotic approaches, to assess the directions of successional development. The authors conducted 96 geobotanical descriptions of the vegetation of agrosteps with indication of total projective coverage for the herb layer and the projective coverage (%) for each species. The ordination of descriptions was carried out on the basis of DCA-analysis with using the PC-ORD program. To compare the selected associations, an indicator of species activity was determined. According to the results of the work, 5 associations of vegetation of agrosteps were identified. In the early stages of the agrosteps development, communities of the Matricaria inodora+Artemisia absinthium association are formed, which are characterized by the dominance of rod-root species. In the communities of the Stipa spp.+Festuca valesiaca association the dense-sod species are actively growing. However, the low competitiveness of dense-sod plants in the climatic conditions of the northern forest-steppe is contributes to the loss of Festuca valesiaca and its replacement by Poa angustifolia, which leads to the formation of the Stipa spp.+Poa angustifolia association. In the agrosteps communities the Calamagrostis epigejos is actively introduced and increases its activity, which leads to the emergence of the Calamagrostis epigejos association.

During the succession of agrostep vegetation, there is a decrease in the activity of anthropogenic and some sown steppe species, but an increase in the activity of meadow herbs in the selected associations was noted. The conducted analysis indicates a low degree of preservation of «feather grass» associations and the formation of communities of stepped meadows.

Keywords: ecosystem restoration, agrosteps, vegetation classification, Kulikovo field.

Funding. The work was supported by the RFBR grant 19-44-710001 («Vegetation cover of Kulikov field and its dynamics under the influence of natural and anthropogenic factors as a basis for the development of approaches for the conservation and restoration of landscape and biological diversity of forest-steppe regions of European Russia»), the agreement with the government of the Tula region DS/305 and the grant of the rector of TulSU for students in Master’s degree programs, No. 8945 GRR_M («Agrosteps of Kulikovo field and their role in carbon deposition as a basis for the creation of a carbon landfill in the Tula region»).

DOI: 10.24412/1993-3916-2023-4-38-47

EDN: PQMMJV

ONTOGENETIC STRUCTURE OF POPULATIONS OF RINDERA TETRASPIS PALL. (BORAGINACEAE) IN ORENBURG REGION

Arid Ecosystems

UDC 58.009:582.948.25

Mustafina A.N., Abramova L.M., Karimova O.A. ONTOGENETIC STRUCTURE OF POPULATIONS OF RINDERA TETRASPIS PALL. (BORAGINACEAE) IN ORENBURG REGION // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 48-55. | PDF

Assessment of the current state of populations of rare plant species using population-ontogenetic methods is used in solving problems of conservation and restoration of natural communities. The object of the study was a rare species of the European part of Russia – Rindera tetraspis Pall. is a little-studied steppe endemic species, declining in numbers. The aim of the study was to study the features of the ontogenetic structure and the current state of coenopopulations (CP) of R. tetraspis in the Cis-Urals of the Orenburg region. In 2016-19 a survey of three administrative districts of the Cis-Urals of the Orenburg region was carried out, as a result, 6 CPs were identified and studied. An assessment of the phytocenotic confinement of the CP was carried out using traditional geobotanical methods. The leading population characteristics are determined: the density of individuals, the ontogenetic composition. As a result of the conducted research, it was revealed that the predominant type of vegetation is desert viticultural, wormwood-brittle-grass-grass calcephytic and curly bluegrass-tyrs steppe communities. The total density in the examined CPs varies from 4.7 to 10.7 ind./m2, the effective density is 3.2-5.9 ind./m2. Ontogeny is described, 8 ontogenetic states are revealed, senile individuals are not found. All the studied CPs of R. tetraspis are normal incomplete, the peak falls on middle-aged generative individuals. According to the delta-omega classification, 3 CPs are young, 2 are transitional, and one is mature. The state of the studied populations is relatively satisfactory. But out of the six studied CPs, only one CP is protected, it is located in the «Troitsky Chalk Mountains». To strengthen the protection of the species, constant monitoring of the state of populations is necessary.

Keywords: rare species, Rindera tetraspis Pall., Boraginaceae, Orenburg region, cоenopopulation, density, ontogenetic structure.

Funding. The work was carried out on the topic of the UUBSI of the UFIC RAS «Biodiversity of natural systems and plant resources of Russia: assessment of the state and monitoring of dynamics, problems of conservation, reproduction, increase and rational use» within the framework of the state task for 2022 of the UFIC RAS No. 075-03-2022-001 dated 14.01.2022.

DOI: OWOUIU

EDN: 10.24412/1993-3916-2023-4-48-55

ASSESSMENT OF THE STATUS OF THE COENOPOPULATION OF ALLIUM PRAEMIXTUM IN VVED. IN THE RANGES OF UZBEKISTAN

Arid Ecosystems

UDC 581.93 (470.67); 581.522.5

Saribaeva Sh.U., Allamuratov A., Mavlyanov B., Mamatkosimov O.  ASSESSMENT OF THE STATUS OF THE COENOPOPULATION OF ALLIUM PRAEMIXTUM IN VVED. IN THE RANGES OF UZBEKISTAN // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 56-62. | PDF

The article presents the results of studying the state of the cenopopulation of a rare species – Allium praemixtum in the Nurata and Turkestan ranges. The ontogenetic structure of the coenopopulation was studied by the generally accepted method (Uranov, 1975; Coenopopulations…, 1976). Coenopopulations were characterized according to the classifications of A.A. Uranov and O.V. Smirnova (1969) and «delta-omega» (Zhivotovsky, 2001). The ecological density was determined according to W. Odum (1986). Geobotanical descriptions were made according to the standard method on plots of 100 m2 (Field geobotany, 1964). The characteristic ontogenetic spectrum is left-sided and with an absolute maximum in one of the pregenerative groups (Cheremushkina, 2004). Coenopopulations 1, 5, 6 correspond to the typical left-sided ontogenetic spectrum with a maximum peak in the virginal state of the species. The centered onogenetic spectrum does not coincide with the characteristic spectrum, culminating in the middle-aged state. The bimodal onogenetic spectrum should be considered as a temporary variant of the left-sided one with an equal peak in the medium generative and virginal states. The density of individuals in the studied coenopopulations varied from 1.1 to 9.7 ind./m2, and the ecological density was 2.3-17.63 ind./m2. According to the “delta-omega” classification, coenopopulations of Allium praemixtum CP 1 are maturing, CP 5 and 6 are young, CP 2.4 are transitional, CP are mature. The existing coenopopulations are mainly located outside the territory of the Nurata Reserve, except for coenopopulation 3 (near Mazhrumsay) and CP 4 (near Gurdarasay). The only solution to this problem can be the strict protection of coenopopulations.

Keywords: biodiversity, Allium praemixtum, phytocenosis, ontogenetic structure, coenopopulation, plant protection.

Funding. The work was carried out within the framework of the project of the state scientific and technical program of the Republic of Uzbekistan «Assessment of the current state of populations and creation of a living collection of economically valuable species of wild relatives of cultivated plants of the flora of Uzbekistan».

DOI: 10.24412/1993-3916-2023-4-56-62

EDN: MRCMAM

VEGETATION OF CRYOARID SOILS: PRODUCTIVITY, SPECIES, ELEMENTAL AND BIOCHEMICAL COMPOSITIONS

Arid Ecosystems

UDC  574.4+631.4

Chimitdorzhieva E.O., Chimitdorzhieva G.D. VEGETATION OF CRYOARID SOILS: PRODUCTIVITY, SPECIES, ELEMENTAL AND BIOCHEMICAL COMPOSITIONS // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 63-72. | PDF

The extreme weather conditions of Transbaikalia, due to which plants experience phytostress, lead to the formation of protective systems and mobilization, in which some metabolic changes occur as a means of survival. These changes include an increase in lipids and lignin. There is a change in metabolism, which is determined by the speed and depth of its changes without disturbing the balance between individual functions, so the unity of the organism and the environment is not disturbed. Cryoarid conditions caused specific morphological and chemical adaptations in plants. It was found that the total content of lipids and lignin in the studied soils of Transbaikalia is higher, and the content of proteins is lower compared to similar soils of the European part of Russia. It was found that more lipids, lignin and proteins were found in virgin chestnut soils compared to fallow and arable ones.

Keywords: vegetation, carbon, productivity, elemental composition, lipids, lignin, proteins, chestnut soils, cryoarid climate, continentality.

Funding. The work was carried out on the topic of state task No. 121030100228-4 «Evolutionary-genetic, biogeochemical and production functions of the soils of the Baikal region as a component of the biosphere, assessment of their resource potential and development of technologies for rational use and protection».

DOI: 10.24412/1993-3916-2023-4-63-72

EDN: MEHGTC

SOILS OF ARID TERRITORIES IN THE CENTRAL PART OF KALMYKIA (ON THE EXAMPLE OF THE PRIYUTNENSKY DISTRICT)

Arid Ecosystems

UDC  631.412

Mukabenova R.A., Mandzhieva S.S., Adyanova A.B., Dzhimbeev N.V., Sayanov V.T., Buluktaev A.A. SOILS OF ARID TERRITORIES IN THE CENTRAL PART OF KALMYKIA (ON THE EXAMPLE OF THE PRIYUTNENSKY DISTRICT) // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 73-80. | PDF

This article presents the characteristics of the soils of the Republic of Kalmykia on the example of the Priyutnensky district. Such indicators of soil fertility as organic matter, the reaction of the aqueous extract medium (hydrogen index – pH), salt composition and the degree of alkalinity of soils of 5 settlements of the Priyutnensky district of the Republic of Kalmykia were studied.. The content of organic carbon (Сorg) was studied by the method of I.V. Tyurin modified by V.N. Simakov (GOST 26213-91), pH of the soil solution by the potentiometric method (GOST 26483-85). The chemical composition of soils was studied by X-ray fluorescence spectroscopy using a MAKS — GV spectroscan. As a result of studies conducted on salt and light chestnut soils of the Priyutnensky district, the predominance of arable soils with low and very low organic matter content (less than 3.5%) was revealed. The reaction of the soil solution is slightly alkaline and alkaline. The soils are saline in the upper surface layer (0-20 cm), the content of exchangeable magnesium does not exceed 0.74%, the content of calcium is 0.96 %, carbonates are present. It has been established that minimum pH values are observed on the edge of settlements, maximum values are observed on the territory of an educational institution, or in the center of a settlement. The chloride content in the soils of the research objects was not the same. There was no pronounced dependence of other soil parameters in all settlements from the center to the background.

Keywords: fertility, salt composition, organic matter, cations, acidity.

Funding. The article was prepared within the framework of the state subsidy for the project «Asymmetrically developing territories facing traditional and new challenges: a study of the dynamics of socio-economic processes and the variability of the environmental situation» (state registration no. 122022700133-9).

DOI: 10.24412/1993-3916-2023-4-73-80

EDN: HWQWRM

MINERALOGICAL AND MATERIAL COMPOSITIONS OF SANDS AND SANDY SOILS IN THE CAINOZOIC DEPRESSIONS OF TRANSBAIKAL REGION

Arid Ecosystems

UDC 631.48

Ubugunova V.I., Ubugunov VL., Varlamov E.B., Bazha S.N., Ubugunov L.L. MINERALOGICAL AND MATERIAL COMPOSITIONS OF SANDS AND SANDY SOILS IN THE CAINOZOIC DEPRESSIONS OF TRANSBAIKAL REGION // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 81-92. | PDF

 Characteristic of climatic, lithological and geomorphological conditions of formation of sandy soils of Transbaikal Region (Barguzin basin) is given. Main pedogenic processes were found to be cryo- and light-humus, accumulative-carbonate, and fawn-metamorphic. The processes of stratification and abrasion are expressed in soils of fallow lands. Moving sands are not involved in soil formation, but embryonic underdeveloped soils (layered-eolian, humus psammozems) have begun to develop with partial fixation of herbaceous and/or shrub vegetation. Composition of the rocks of the Angara-Vitim batholith, soil-forming sand, as well as the composition of minerals of fractions <1, 1-5 and >5 µm in cryo-humus and light-humus soils are presented for the first time. The regional features of parent sands have been determined to be carbonation, alkalinity and polymineral content, proceeded from the calcic-alkaline rocks. Sandy and silty soil fractions are of similar mineralogical composition with a high content of plagioclases and K-feldspars, and a low quartz amount. The silty fraction is composed by a mixed-layerd phase of illite-smectites interlayered with a single chlorite packets, di-three-octaedric illite, ferruginous chlorite, and kaolinite. Current soil formation is characterized by a low degree of chemical weathering (CIA, CIW, GM) and weak profile differentiation. An increased content of potassium and sodium are the feature of the material composition of sandy soils. Soils under the study correspond to the category of high-alkaline according to the values of total alkalinity. Biological activity is clearly distributed down soil profile. It was revealed that sandy soils have a potential risk of desertification with arable use: within the studied area, all arable lands and fallows located there are deflated to varying degrees. More than 70% of the area has been found to belong to very strongly deflated and strongly deflated. In such lands, humus soil layers are blown out, and carbonate horizons and even parent sands are exposed. The exposed middle horizons and sands are not effectively fertile. The yield of agricultural crops on such arable lands is very low. The process of natural restoration of vegetation cover on fallow lands is extremely difficult, and deflation ulcers practically do not overgrow. Alkalinity and carbonation of soil-forming sands are largely inhibited the processes of natural coenoses restoration.

Keywords: sandy soils, texture fractions, mineralogical composition, Transbaikal Region, Barguzin depression, desertification.

Funding. The work was carried out on the topics of state assignments: the Institute of General and Experimental Biology SB RAS «Evolutionary-genetic, biogeochemical and production functions of the soils of the Baikal region as a component of the biosphere, assessment of their resource potential and development of technologies for rational use and protection» (No. 121030100228-4) and the A.N. Severtsev Institute of Problems of Ecology and Evolution RAS «Historical ecology and biogeocenology» (No. 0109-2019-0007), with the support of the V.R. Filippov Buryat State Agricultural Academy (Theme I, Sub-theme I.03).

DOI: 10.24412/1993-3916-2023-4-81-92

EDN: IJOHVA

A HORSE FROM THE RUSSIAN RED BOOK

Arid Ecosystems

UDC 599.735.53:591.5.

Lushchekina A.A., Karimova T.Yu., Neronov V.M. A HORSE FROM THE RUSSIAN RED BOOK // Arid Ecosystems. 2023. Vol. 29. № 4 (97). P. 93-102. | PDF

The Przewalski’s horse (Equus przewalskii Poljakov, 1881) is one of 13 species included in the List of rare and endangered wildlife species that require priority measures for restoration and reintroduction. The species is listed on the Red List of the World Conservation Union (IUCN) and Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). It is the last surviving species from a group of the once numerous and diverse wild horses of Eurasia. The history of the discovery of  the Przewalski’s horse, its description, systematics, other features of biology, issues of restoration and reintroduction, being of great interest to world science, have deserved and deserve special attention of researchers of both the former Soviet Union and pre-revolutionary and modern Russia, who stood at the origins of the conservation of this species. The experience accumulated by the specialists of our country in a number of international projects on reintroduction of  the Przhevalski’s horse and recreating its natural populations served as the basis for preparing programs on creating breeding centers and forming its semi-free populations, which are implemented, first of all, on the territory of «Orenburgsky» State Nature Reserve. A long-term strategy with envisaged and transparent mechanisms of coordination and cooperation of all organizations involved in its realization, providing for science-based approaches and applying modern research methods in its implementation, will contribute to successful realization of «The Przhevalski’s horse Breeding Program in the Russian Federation» approved by the Russian Ministry of Natural Resources on April 8, 2022.

Keywords: the Przhevalski’s horse, Red Book, historical range, reintroduction.

Funding. The work was carried out on the topic of research at the Institute of Ecology and Evolution named after A.N. Severtsov of the Russian Academy of Sciences, state task No. FFER-2024-0022 «Fundamental principles of wildlife protection and rational nature management».

DOI: 10.24412/1993-3916-2023-4-93-102

EDN: JHWJJG