In the next Issue Arid Ecosystems. 2023. V.29. № 4 (97)

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 4-20

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UDC 581.5

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

*Water Problems Institute of the Russian Academy of Sciences

3, Gubkin str., Moscow, 119333, Russia. Е-mail: nmnovikova@gmail.com

**Karakalpak State University named after Berdakh

1, Charjoya Abdirova Str., Nukus, Republic of Karakalpakstan, 230112, Uzbekistan.

E-mail: nukusgiscenter@gmail.com

Received 25.04.2023. Revised 15.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 21-29

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UDC 581.93 (470.67)

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

Mountain Botanical Garden DFRC RAS

45, M. Gadzhieva Str., Makhachkala, 367000, Russia. E-mail: sadykova_gula@mail.ru

Received 15.02.2023. Revised 7.07.2023. Accepted 10.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 30-37

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UDC 574.42; 574.9

IS THERE UPLAND XEROPHITES IN THE MOUNTAINS OF SOUTH SIBERIA?

Tomsk State Pedagogical University

60, Kievskaya Str., Tomsk, Tomsk region, 634061, Russia. E-mail: volkovhome@yandex.ru

Received 14.11.2022. Revised 04.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 38-47

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UDC 581.524.31; 581.55; 502.2.05; 504.052

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

*Tula State University

92, pr. Lenina, Tula, 300012, Russia

**Museum-reserve «Kulikovo field»

47, pr. Lenina, Tula, 300041, Russia. E-mail: convallaria@mail.ru

Received 22.09.2022. Revised 10.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 48-55

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UDC 58.009:582.948.25

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

South-Ural Botanical Garden-Institute of Ufa Federal Scientific Centre of the Russian Academy of Sciences

195/3, Mendeleeva Str., Ufa, 450080, Russia. Е-mail: alfverta@mail.ru

Received 07.07.2022. Revised 27.05.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 56-62

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UDC 581.93 (470.67); 581.522.5

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

Institute of Botany Academy Sciences Republic of Uzbekistan

32, Durmon yuli, Tashkent, 100125, Uzbekistan. E-mail: ssaribayeva@list.ru

Received 20.04.2022. Revised 30.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 63-72

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UDC 574.4+631.4

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

Institute of General and Experimental Biology of the Siberian Branch of the Russian Academy of Sciences

6, Sakhyanova Str., Ulan-Ude, 670047, Russia. E-mail: erzhena_ch@mail.ru

Received 09.02.2023. Revised 30.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 73-80

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UDC 631.412

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

*Kalmyk Scientific Center of the Russian Academy of Sciences

8, I.K. Ilishkin Str., Elista, 358000, Russia. E-mail: Raisa.mukabenova@mail.ru

Received 20.02.2023. Revised 15.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 81-92

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UDC 631.48

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

S.N. Bazha***, L.L. Ubugunov*, ****

*Institute of General and Experimental Biologyof the Siberian Branch of teh Russian Academy of Sciences

6, Sakhyanovoi Str., Ulan-Ude, 670047, Russia. E-mail: ubugunova57@mail.ru

** V.V. Dokuchaev Soil Institute.

7/2, Pyzhevsky per., Moscow, 119017, Russia. E-mail: evgheni968@yandex.ru

*** A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences

33, Leninsky pr., Moscow, 119071, Russia. E-mail: monexp@mail.ru

**** V.R. Filippov Buryat State Agricultural Academy

8, Pushkin Str., Ulan-Ude, 670047, Russia. E-mail: l-ulze@mail.ru

Received 13.01.2023. Revised 30.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 93-102

═══════════════ SYSTEMATIC STUDY OF ARID TERRITORIES ══════════════

UDC 599.735.53:591.5.

A HORSE FROM THE RUSSIAN RED BOOK

A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences

33, Leninsky Prospect, Moscow, 119071, Russia. E-mail: rusmabcom@gmail.com

Received 10.05.2023. Revised 30.06.2023. Accepted 01.07.2023.

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

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 103-116

═══════════════ SYSTEMATIC STUDY OF ARID TERRITORIES ══════════════

UDC 598.2:598.243 (1/3)

POPULATION TRENDS OF WADERS ON THE ARID COAST OF THE WESTERN CASPIAN DURING THE EPOCH OF CLIMATE WARMING

Precaspian Institute of Biological Resources of the Daghestan Federal Research Centre

of the Russian Academy of Sciences

45, M. Gadzhiev Str., Makhachkala, Daghestan, 367000, Russia. E-mail: evberkut@mail.ru

Received 15.05.2023. Revised 06.06.2023. Accepted 01.07.2023.

The decline in the number of waterbirds on a global scale is largely due to the reduction in wetland areas in the era of climate warming. Droughts that started in 1968–73 in Africa, gradually covered the northern and southern hemispheres. In order to diagnose the state of semiaquatic bird populations, we selected waders (suborder Charadrii of the order Charadriiformes) as a model group. It is almost impossible to estimate the absolute abundance of Charadrii in the nesting areas of the Arctic, forest, forest-steppe and steppe zones of Russia, while it is possible to determine the state of their migratory populations at the level of trends at the nodal points of migration. The presented work reflects the data of long-term monitoring of migratory wader populations obtained in 1995-2020 in two IBAs of international importance – the Sulakskaya and Turalinskaya lagoons (Republic of Dagestan). The model wetlands are located on one of the largest in Russia West Caspian bottleneck flyways (Caucasian-Caspian Migration Corridor), where the flyways of European and Asian migrants intersect. The model group of waders, which includes 10 mostly background taxa, was chosen based on the regularity of their encounters during migration. Weekly year-round counts of waders were carried out without limiting the width of the transect, followed by separate recalculation per area according to the average group detection ranges. Based on the data on ring returns obtained from the ringing center of the IEE RAS, the conditional outline of the generalized range of Charadrii was determined, the faunogenetic basis of which is the widespread, Arctic and Siberian representatives of fauna types. The proportion of participation of each species and the “core” of the Charadrii population in the study area for the entire monitoring period was determined. Using regression analysis, the model group of shorebirds was divided into 3 subgroups depending on the direction of the trend of their long-term abundance. Using correlation analysis, a model group of waders (n = 5) was identified, which was significantly associated with an increase in the average annual air temperature in the Primorskaya lowland of Dagestan. Correlation analysis showed a weakly pronounced negative trend in the total abundance of 10 Charadrii model taxa encountered over the entire study period. There is a correlation between changes in air temperature with the number of 10 model taxa, in 3 of which the number significantly decreased, in 2 – increased, in 5 – remained at the same level. A correlation was found between the average monthly temperature in September in the Caspian lowland of Dagestan with the abundance of stilt (r = -0.56, p = 0.007) and snipe (r = -0.50, p = 0.019). It has been proven that in cold years the number of migrating Charadrii and the intensity of their migration in the study area increases, while in warm years it decreases as a result of changes in migration paths, places of permanent stops and wintering. At the same time, the number of populations themselves remains unchanged. Thus, the trends in the number of waders obtained at the nodal points of migration can be taken as a reliable assessment of the state of specific geographical populations of Charadrii regularly migrating along the western Caspian, which is confirmed by ringing data and synchronized with information from literary sources. Three key factors influencing the dynamics of wader populations are discussed: hydroclimatic cycles, anthropogenic impact, and foraging. The current state of the populations of the model group of birds reasonably assumes the introduction of a temporary ban on the hunting of 4 species of waders with a negative population trend (Northern Lapwing, Common Redshank, Common Snipe and a Black-tailed Godwit) until a steady recovery of their populations. The data obtained can serve as the basis for the creation of the Russian Charadrii monitoring database with its subsequent integration with existing databases in Eurasia. In order to preserve the biodiversity of the studied lagoons (including shorebirds), according to ornithological monitoring conducted by the author, the Sulakskaya Lagoon PA has already been created with the status of regional significance and an innovative socio-ecological project of the Ornithopark – Turalinskaya Lagoon Natural Park has been developed.

Keywords: Charadrii, lagoons of Dagestan, range, abundance trends, factors.

Funding. The work was carried out with financial support within the framework of the State Assignment of the Caspian Institute of Biological Resources – a separate subdivision of the Dagestan Federal Research Center of the Russian Academy of Sciences, registration number 122032200288-0 on the topic: «Structural and functional organization and dynamics of animal populations and communities, methodological foundations for monitoring biological diversity and scientific foundations for the conservation and management of biological resources of zonal ecosystems of the Eastern Caucasus».

DOI: 10.24412/1993-3916-2023-4-103-116

EDN: RFMKYG

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 117-126

════════════════ SYSTEMATIC STUDY OF ARID TERRITORIES ══════════════

UDC 591.9;59.009;913

MAPPING OF BIODIVERSITY IN THE ARID REGIONS OF KAZAKHSTAN WITH EVALUATION OF EFFECTIVENESS OF ITS TERRITORIAL PROTECTION

M.V. Lomonosov Moscow State University, Faculty of Geography

1, Leninskie Gory, Moscow, 119992, Russia. E-mail: tanikdik@yandex.ru

Received 26.04.2023. Revised 01.05.2023. Accepted 01.07.2023.

Using the biogeographical approach, we analyzed and mapped the protected terrestrial vertebrate species in Kazakhstan for the aims of revealing of territories with high faunal diversity and evaluation of efficiency of the special protected territories net. We analyzed the spatial distribution of protected terrestrial vertebrates by taxonomic groups (mammals, birds, amphibians and reptiles – 109 species total) and their combinations as well as according by their protection status. We identified the places of concentration of protected vertebrate species as priority territories for conservation in Kazakhstan. We also made evaluation of efficiency of distribution of existing net of specially protected territories. Maps were made using grid mapping. This method makes it possible to compare the results with other arid marco-regions. We showed the role of several reserves, national parks and large wildlife preserves in protection of biodiversity in Kazakhstan. We formulated and justified recommendations for development of the special protected territories net for the aims of conservation of the territories with high biodiversity and aims of research works in this direction.

Keywords: faunal diversity, grid mapping, spatial distribution of protected species, efficiency of spatial distribution of specially protected territories.

Funding. The article was carried out within the framework of the topic of state task No. 121051100137-4 of the Geographical Faculty of Lomonosov Moscow State University and the scientific and educational school «The future of the planet and global environmental changes» under the program «Climate and Environment».

DOI: 10.24412/1993-3916-2023-4-117-126

EDN: SUHNQE

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 127-134

════════════════ SYSTEMATIC STUDY OF ARID TERRITORIES ══════════════

UDC 574.2:599.32

THE STATE FOOD RESOURCES AND FEEDING SELECTIVITY OF THE MIDDAY GERBIL (MERIONES MERIDIANUS) IN THE ARIDI CONDITIONS OF THE NORTH-WESTERN CASPIAN

*Precaspian Institute of Biological Resources of the Daghestan Federal Research Centre

of the Russian Academy of Sciences

45, M. Gadzhiev Str., Makhachkala, Daghestan, 367000, Russia. E-mail: rizvan12345@rambler.ru

**Dagestan State University

43, M. Gadzhiev Str., Makhachkala, 367000, Russia. E-mail: omarovkz@mail.ru

Received 26.05.2023. Revised 30.06.2023. Accepted 01.07.2023.

In 2015-2018 a study was made of the species composition, productivity of vegetation cover and the composition of the diet of midday gerbils in the arid zone of the North-Western Caspian region. Midday gerbils use all types of available food in their diet, but in different seasons of the year they can vary significantly in percentage. Using the method of cuticular-scatological analysis, it was shown that in the spring in the diet of midday gerbils, the largest share is made up of protruding Velcro (K = 15.97), common barley (K = 9.5) and alfalfa (K = 5.4); in summer — bulbous bluegrass (K = 12.3), white amaranth (K = 3.5) and Siberian wheatgrass (K = 4.3). In autumn, high rates of selectivity are characteristic of bulbous bluegrass (K = 13.2). In winter, midday gerbils feed mainly on the seeds of white amaranth (K = 11.2) and Siberian wheatgrass (K = 2.5), as well as bluegrass bulbs (K = 14.3). In winter, there is practically no selectivity in nutrition in the diet of midday gerbils, and they use all the food available at this time of the year.

Keywords: Northwestern Caspian, Meriones meridianus, diet composition, food selectivity.

Funding. The work was carried out with financial support within the framework of the state assignment of the Caspian Institute of Biological Resources, a separate subdivision of the Dagestan Federal Research Center of the Russian Academy of Sciences, registration number 122032200288-0.

DOI: 10.24412/1993-3916-2023-4-127-134

EDN: SXZDVX

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 135-147

════════════════ SYSTEMATIC STUDY OF ARID TERRITORIES ══════════════

UDC 551.582;551.583.1(470.31)

SPATIAL-TEMPORAL VARIABILITY OF THE DISTRIBUTION OF CLIMATE INDICATORS OF THERMAL AGROCLIMATE RESOURCES (ARARAT VALLEY AND FOOTHILL ZONE, ARMENIA)

*Yerevan State University

1, Alek Manoukian Str., Yerevan, 0025, Armenia. Email: vmargaryan@ysu.am

**Russian State Hydrometeorological University

98, Malookhtinsky prospect, St. Petersburg, 195196, Russia. Email: oderiut@mail.ru

***National Polytechnic University of Armenia (NPUA)

105, Teryan Str., Yerevan, 0009, Armenia. E-mail: asedrakyan.phys@gmail.com

Received 20.12.2022. Revised 27.05.2023. Accepted 01.07.2023.

In this work, the characteristics of thermal agro-climatic resources of the Ararat valley and the foothill zone are studied and calculated, the patterns of their spatial and temporal distribution, as well as interannual variability, are analyzed and evaluated. Previously published works and relevant studies served as theoretical and informational foundations for this work. Daily data of actual observations of meteorological stations of the «Hydrometeorology and Monitoring Center» SNCO of the Ministry of Environment of the Republic of Armenia in the study area, as well as agro-climatic reference books and yearbooks were used as the source material. The following methods were applied in the work: mathematical-statistical, extrapolation, interpolation, analytical, correlation, as well as methods of analysis and analogue.

It turned out that the territory of the Ararat valley and the foothill zone, which has a relatively arid climate, is the most favorable agricultural region of the republic in terms of climatic indicators of thermal agro-climatic resources. The thermal conditions of the region are favorable for the growth and development of various crops; however, the danger of late spring and early autumn frosts must be considered. Measures for adapting agricultural production to climate change are proposed. The results obtained can be used in planning the development of agricultural production on the territory of the Ararat valley and the foothill zone, in the development of agro-climatic cadastres of territories and climatic services for sectors of the national economy.

Keywords: dates of stable transition of the average daily air temperature through 0, 5 and 10°C in spring and autumn, climatic spring, climatic autumn, growing season, climate change, Ararat valley and foothill zone, Armenia.

Funding. The work was supported by the Science Committee of RA, in the frames of the research project 21T-1E215 «Hydro-ecological assessment of winter low water period discharge characteristics of lake Sevan basin rivers»

DOI: 10.24412/1993-3916-2023-4-135-147

EDN: TDVLJJ

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 148-153

════════════ SECTORAL PROBLEMS OF DRYLANDS DEVELOPMENT ═══════════

UDC 551.583.13

ANALYSIS OF THE VARIABILITY OF AGROCLIMATIC CONDITIONS IN SEMI-DESERT AND DESERT LANDSCAPES OF THE NORTHERN CAUCASUS FOR AGRICULTURAL PURPOSE

Grozny State Oil Technical University named after Academician M.D. Millionshchikov,

100, Kh.A. Isaeva Str., Grozny, Chechen Republic, 364902, Russia. E-mail: eip-eco2017@yandex.ru

Received 13.07.2022. Revised 18.05.2023. Accepted 01.07.2023.

The aim of the study is a modern assessment of the agro-climatic resources of the semi-desert and desert landscapes of the North Caucasus. The methods of mathematical statistics used in agroclimatology are used to analyze changes in average monthly and annual air temperatures, growing season, precipitation, hydrothermal coefficient according to five weather stations with a long series of observations. Within the semi-desert and desert landscapes of the North Caucasus, there is an increase in annual air temperature for the period under review by an average of 0.86°C compared to the previous period. The sum of active temperatures increased by 9-11%. The duration of the period increased when passing through 0°C for 17 days, 5°C for 15 days, 10°C for 10 days and 15°C for 8 days. An increase in precipitation is noted at all meteorological stations, except for Makhachkala. On average, precipitation increased by 36 mm. The HTC varies from 0.5 to 0.7 and is within the limits of natural fluctuation. Modern agro-climatic changes within the semi-desert and desert landscapes of the North Caucasus are characterized by an improvement in the conditions for heat and moisture supply to the territory. These conditions are favorable for the cultivation of melons and all types of grape varieties, with the exception of very late ones.

Keywords: modern agro-climatic changes, landscape, temperature, precipitation, hydrothermal coefficient, vegetation period.

Funding. The work was carried out within the framework of the state task No. FZNU-2021-0002 of the Grozny State Petroleum Technical University «Assessment of the variability of agro-climatic conditions of the North Caucasus in connection with global climate changes».

DOI: 10.24412/1993-3916-2023-4-148-153

EDN: URYUAI

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 154-165

════════════ SECTORAL PROBLEMS OF DRYLANDS DEVELOPMENT ═══════════

UDC 581.5 (575.13)

ECOLOGICAL AND PHYTOCENOTIC CHARACTERISTICS OF HALOCNEMETA STROBILACEI PASTURE OF KARAKALPAK USTURT

Institute of Botany of the Academy of Sciences of the Republic of Uzbekistan

32, Durmon yuli Str., Tashkent, 100125, Uzbekistan. E-mail: spring_girl93@mail.ru

Received 24.01.2023. Revised 30.06.2023. Accepted 01.07.2023.

The article presents the ecological and phytocenotic characteristics of the Halocnemeta strobilacei type of pastures common on the territory of the Karakalpak Ustyurt (Uzbekistan). The species composition, the productivity of pasture differences, the type of soil, the percentage of projective grass cover, landscape types are characterized, the recommended seasonality of use is determined. According to geobotanical zoning, the Halocnemeta strobilacei type of pasture covers the territory of the Barsakelmes, Sarykamysh and Churuk districts of the Karakalpak Ustyurt and occupies 123736 hectares. This type consists of three pasture differences: Halocnemum strobilaceum, Haloxylon ammodendron-Halocnemum strobilaceum, Kalidium capsicum-Halocnemum strobilaceum, common on wet and plump salt marshes with very close occurrence of highly mineralized soil water, as well as on loamy and sandy loam saline soils. The differences are characterized by sparsity of vegetation cover and extreme poverty of species composition, reaching in some cases to a monodominant community. Such a poverty of the species composition of Halocnemeta strobilacei type is explained by the presence of a high concentration of soil solution, to which a limited number of species are adapted. The seasonal productivity ranges from 0.9 to 4.3 kg/ha, According to estimates of the yield of the eaten part (kg/ha), it is recommended to use the studied pasture differences as an autumn-winter pasture.

Keywords: Ustyurt plateau, aridization, pasture, productivity, pasture load, bonitet, degradation.

Funding: The work was carried out within the framework of the state program (PFI-5) «Assessment of the current state of vegetation cover and pasture resources of the Republic of Karakalpakstan».

DOI: 10.24412/1993-3916-2023-4-154-165

EDN: WVFXAY

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 166-176

════════════ SECTORAL PROBLEMS OF DRYLANDS DEVELOPMENT ═══════════

UDC 631.453:632.122.2

ASSESSMENT OF THE EFFICIENCY OF BIOREMEDIATION BY OIL-CONTAMINATED EUTRIC CAMBISOLS IN THE REPUBLIC OF KALMYKIA (MODEL EXPERIMENT)

D.I. Ivanovsky Academy of Biology and Biotechnology of the Southern Federal University

194/1, Stachki av., Rostov-on-Don, 344090, Russia. E-mail: loko261008@yandex.ru

Received 20.02.2023. Revised 06.07.2023. Accepted 01.07.2023.

Eutric Cambisols of the Republic of Kalmykia are subject to high levels of oil pollution. To assess the ecological state of soils, it is necessary to analyze not only the residual oil content, but also the biological indicators of soils. The purpose of this work is to evaluate the effectiveness of bioremediation of the oil-contaminated Eutric Cambisols of the Republic of Kalmykia with the help of physicochemical and biological indicators. Biochar, nitroammophos, sodium humate, and «Baikal EM-1» were added to oil-contaminated soil (5% of the soil mass). To assess the effectiveness of remediation of Eutric Cambisols after 30 days, the residual oil content, the activity of catalase and dehydrogenases, the number of bacteria, the length of roots, and germination of radish were studied. It has been established that the introduction of biochar and «Baikal EM-1» reduces the residual oil content in Eutric Cambisols. Biochar and nitroammophos affect the content of easily soluble salts, and «Baikal EM-1» – on the redox potential. Sodium humate stimulates catalase activity (r = -0.48), length of shoots (r = -0.54), length of roots (r = -0.54), and germination of radish (r = -0.64). Nitroammophos stimulates the number of bacteria (r = -0.56), activity of catalase (r = -0.63) and dehydrogenases (r = -0.84), but inhibits the length of shoots and roots of radish (Raphanus sativus L.). The introduction of «Baikal EM-1» stimulates the number of soil bacteria (r = -0.83), the activity of dehydrogenases (r = -0.89) and inhibits germination and the length of roots, shoots. It is advisable to use the results of the study in biomonitoring and diagnosing the state of oil-contaminated Eutric Cambisols of the Republic of Kalmykia.

Keywords: soil, remediation, ecological state, bioindication.

Funding. The study was supported by a grant from the President (MK-175.2022.5), with the financial support of the project of the Strategic Academic Leadership Program of the Southern Federal University (“Priority 2030”) for the creation of the Youth Laboratory of Ecobiotechnologies for Diagnosis and Protection of Soil Health (No. SP-12-23-01 ), the Ministry of Science and Higher Education of the Russian Federation, the laboratory «Soil Health» of the Southern Federal University (agreement No. 075-15-2022-1122), the project of the Ministry of Education and Science of Russia «Laboratory of Young Scientists» within the framework of the Interregional Scientific and Educational Center of the South of Russia (No. LabNOTS- 21-01AB, FENW-2021-0014).

DOI: 10.24412/1993-3916-2023-4-166-176

EDN: YVASSE

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 177-186

═════════════ WATER ECOSYSTEMS OF ARID TERRITORIES ════════════════

UDC 574.587

ASSESSMENT OF BOTTOM COMMUNITIES OF RIVERS TAKING INTO ACCOUNT “DARK AND GRAY VARIETY” OF SPECIES: APPROACHES TO THE SOLUTION

Institute of Ecology of the Volga Basin of the Russian Academy of Sciences – branch of the Samara Federal Research Scientific Center of the Russian Academy of Sciences

10, Komzina Str., Togliatti, 445003, Russia. E-mail: zinchenko.tdz@yandex.ru

Received 13.05.2023. Revised 22.06.2023. Accepted 01.07.2023.

The species diversity of the entire meta-community is composed of local pools of species of individual communities, including both a set of actually observed taxonomic groups and species of «dark» diversity, which by their ecological properties are theoretically suitable for habitat in the existing conditions and are potentially found in repeated studies. To assess the dark diversity, quantitative indices of suitability are calculated for the surveyed areas of the study area in relation to the various taxa of the community in question. The species composition of bottom communities was studied in small and medium plain rivers, tributaries of Kuibyshev, Saratov and Volgograd reservoirs, including rivers of arid region of Lake Elton basin. A total of 132 local communities were surveyed from which 147 macrozoobenthos taxa were selected for calculations. Analysis of co-occurrence of species was carried out to identify dark diversity and, using formulas of hypergeometric distribution, estimates of conditional probabilities of statistical association of each of these species with certain river sections were calculated. Dependencies between observed species richness and dark diversity were considered; the occurrence of latent species in river sections of similar type was tested. We introduce the concept of «gray» diversity, a subset of observed species with focal area indices less than a given threshold.

This work was performed according to the research topic «Assessment of current biodiversity and forecast of its changes for the ecosystems of the Volga river basin under conditions of their natural and anthropogenic transformation» and with the financial support of the Russian Foundation for Basic Research, grant № 17-04-00135.

Keywords: macrozoobenthos, small and medium rivers, species pool, dark and gray diversity, matching index, co-occurrence, hypergeometric distribution

Funding. The work was carried out on the research topic «Change, sustainability and conservation of biological diversity under the influence of global climate change and intense anthropogenic pressure on the ecosystems of the Volga basin. The registration number of the state task is 1021060107212-5-1.6.20; 1.6.19 and with the financial support of the Russian Foundation for Basic Research, grant No. 17-04-00135 «Functional features of the organization of the structure of planktonic and bottom communities of river ecosystems on the example of salty rivers of the hypergaline lake basin. Elton.»

DOI: 10.24412/1993-3916-2023-4-177-186

EDN: ZZAMBH

ARID ECOSYSTEMS, 2023, Vol.29, No. 4 (97), P. 187-201

═════════════ WATER ECOSYSTEMS OF ARID TERRITORIES ════════════════

UDC 574.58 (571.54/55)

BIODIVERSITY OF HYDROBIONTS IN SODA, CHLORIDE, AND SULPHATE LAKES (TRANSBAIKALIA, RUSSIA)

Institute of Natural Resources, Ecology and Cryology of the Siberian Branch

of the Russian Academy of Sciences

16a, Nedorezova Str., Chita, 672014, Russia. E-mail: balgit@mail.ru, svb@mail.ru, nattash2005@yandex.ru, kataf@mail.ru, benthos@yandex.ru, gazhit@bk.ru, kap0@mail.ru

Received 28.03.2023. Revised 06.07.2023. Accepted 01.08.2023.

The article presents the results of a comprehensive hydrochemical and hydrobiological study of 13 different lakes in Transbaikalia carried out in July 2022. Based on cluster analysis of the hydrochemical and hydrobiological indicators, the studied lakes were divided into three groups: 1) brackish soda lakes; 2) chloride and sulfate lakes and one salty soda lake, Lake Shvartsevskoye; and 3) soda brine lakes. It was found that the number of species of different groups of hydrobionts decreases with increasing salinity of water. At the same time, the number of species of different groups of hydrobionts does not depend on the chemical type of water. However, the dominant composition of primary producers in lakes of different types differs. Two new species of macroalgae (Stigeoclonium flagelliferum Kütz., Rhizoclonium riparium (Roth.) Harv.) were identified for Transbaikalia. After more than a 100-year hiatus, the presence of Ruppia maritime L. was confirmed in the aquatic flora of Siberian Baikal. Galotolerant species dominate in the zooplankton of the lakes. In the dominant structure of the zoobenthos of brine and salty lakes, Artemia shrimp and Ephydridae flies are prevalent. In deeper brackish lakes, representatives of the Chironomidae mosquito family are permanent dominants. Quantitative indicators of phytoplankton and zooplankton communities are characterized by an inverse relationship. For example, during the massive development of cryptophytic algae in brine water bodies, the numerical values and biomass of zooplankton are minimal. No specific tendencies were identified in the range of fluctuations in the biomass of zoobenthos and the phytomass of aquatic plants. The trophic structure of heterotrophs in sulfate and chloride lakes is presented in the zooplankton by a grazing chain, while detritivores dominate in the zoobenthos.

Key words: salinity, phytoplankton, macrophytes, zoobenthos, zooplankton, primary production, chlorophyll a.

Funding. This work was carried out for the Grant No. 22-17-00035 of the Russian Science Foundation “Ecology and Evolution of Aquatic Ecosystems under Conditions of Climatic Fluctuations and Anthropogenic Pressure”.

DOI: 10.24412/1993-3916-2023-4-187-201

EDN: SWFILX