Davydova N.D. TRENDS IN HYDROTHERMAL INDICATORS OF THE STEPPES OF SOUTH-EASTERN TRANSBAIKALIA IN THE CONTEXT OF CLIMATE WARMING // Arid ecosystems. 2022. V.28. № 1 (90). P. 3-10 .
Received May 27, 2021. After revision October 11, 2021. Accepted October 12, 2021.
One of the problems of the development of society on Earth was climate change due to the increase in the temperature of the surface layer of air, which for different regions was and remains not equal. The analysis of long-term data on air temperature, atmospheric precipitation and humidity of deep-frozen powdery-carbonate chernozems of the Onon-Argun steppe of South-Eastern Transbaikalia is carried out. It is shown that the next dry period of 1999-2020 differs from the previous one by a significant increase in temperature and an ambiguous annual amount of precipitation. According to these indicators, it is divided into two parts: very dry warm and wet very warm. In the driest period (2001-2011), the moisture reserves in the soils were mostly at the level of withering humidity and below. In nature, there were such catastrophic phenomena as the widespread drying of stands of trees, the disappearance of lakes, including a large one-Barun-Torey. Since 2012, the amount of precipitation has increased, but has had little effect on the soil moisture reserves and the replenishment of the water volume in the lakes. As a result, by 2018, the water area of another large lake of the Torey depression – Zun-Torey-disappeared. The bottoms of the dried-up lakes turned into soda-sulfate sodium and soda- chloride-sulfate sodium salt marshes. In the terrestrial grassland of the steppes, the introduction of xerophilic species into the communities was observed, as well as a decrease in its height and density. The amount of aboveground plant mass decreased by 1.5-2.0 times.
Keywords: global warming, Onon-Argun steppe, atmospheric precipitation, air temperature, humidity, soil, lake drying, vegetation, xerophilic species, stand of trees.
Acknowledgement. The author is grateful to the head of the Borzya meteorological station, L.I. Karpikova, hydrologist O.V. Perminova and all the employees who worked in different years for their long-term assistance in the selection of materials, consultations, understanding and warm friendly attitude, as well as Ph.D. L.V. Dudareva, who took a direct part in the formation of the Chemical Analytical Center of the Institute of Geography of the SB RAS and its accreditation, the development of the instrument base and the receipt of KHA data.
Financing. The work was carried out at the expense of the state assignment of the IG SB RAS, state registration No. AAAA17-117041910171-7, “Spatial and temporal patterns of the material state of the landscapes of Siberia in changing environmental conditions”.
UDC 551.511.61; 551.513.22
Tleumuratova B.S., Narymbetov B.Zh. CONVECTIVE AEROSOL REMOVAL IN DESERT ZONES AS A FACTOR OF AIR TEMPERATURE RISE // Arid ecosystems. 2022. V.28. № 1 (90). P. 11-19.
Received September 10, 2021. After revision Jctjber 14, 2021. Accepted October 15, 2021.
The article discusses aerosol pollution of the atmosphere in the Southern Aral Sea region as a factor of climate change in this region. The main causes of pollution are wind and convective removal of soil particles from the underlying surface. The differences between these two types of emissions are shown. Since the effect of wind removal of aerosol from the drained bottom of the Aral Sea on the regional climate has been studied in our previous studies, in this paper, only convective removal of soil microparticles from desert surfaces is considered (for the first time) as a factor of increasing summer air temperatures in the Southern Aral Sea region. The paper presents the results of calculations of the mass concentration of aerosol in the surface layer of the atmosphere caused by convective flows. The quantitative assessment obtained by mathematical modeling methods showed the significance of convective aerosol removal in the Southern Aral Sea region, which increases the aerosol concentration to 1.2 mg/m3. As a result of numerical experiments, the dependence of the air temperature increase by convective removal of soil particles on the aerosol dispersion in the range of 0.3-5°C was revealed. The absence of precipitation in the Southern Aral Sea region in July-August, which counteracts the convective removal of soil aerosol by leaching the aerosol from the atmosphere and wetting the underlying surface, ensures a continuous flow of aerosol particles into the atmosphere, which increases the climate-forming effect of the process under consideration.
Keywords: convective removal, aerosol, near-surface air temperature, climatic forcing, Southern Aral Sea region.
Acknowledgement. The authors are grateful to Dr. B.F. Abdurakhimov, Professor of the Department of Applied Mathematics and Computer Analysis of the National University of Uzbekistan for the hypothesis expressed in a private conversation about the possibility of climatic forcing of air temperature by convective emission of particles of the heated underlying surface.
Financing. The research was carried out within the framework of the state task «Research by methods of mathematical modeling of the dynamics of ecological and climatological processes in the Southern Aral Sea region».
Gubarev D.I., Levitskaya N.G., Derevyagin S.S. INFLUENCE OF CLIMATE CHANGE ON SOIL DEGRADATION IN ARID ZONES OF THE VOLGA REGION // Arid ecosystems. 2022. V.28. № 1 (90). P. 20-27.
Received July 19, 2021. After revision October 14, 2021. Accepted October 15, 2021.
The aim of the research was to establish the impact of climate change on the processes of soil degradation and desertification in the arid zones of the Volga region. The material for the research was the observational data for 1971-2020 on 20 meteorological stations, as well as the results of soil-ecological and hydrogeological monitoring at research stations of the Federal State Budgetary Scientific Organization «Federal Center of Agriculture Research of the South- East Region» in the prevailing soil and climatic zones on the territory of the Saratov region (forest-steppe, steppe, dry steppe and semi-desert). Identified signs accompanying aridization, desertification and land degradation differentiated by natural zones. In particular, the average annual air temperature increased, compared with the climatic norm, by 1.0-1.2°С, the greatest increase was observed in August (by 2.0-2.2°С). The average temperature of the soil surface during the warm period increased by 1.1-1.5°C. The risks of severe atmospheric droughts during the entire growing season increased throughout the entire territory, most noticeably in the semi-desert zone (from 55 to 82%). The amount of precipitation in the spring increased by 10-25%, and in the summer – decreased by 23-30%. The boundaries of the semi-desert zone have shifted to the north and northwest. The tendency of changes in the hydrological regime of zonal soils from non-leaching to periodically leaching in 20-40% of years is outlined. The values of the aridity indices of the territory, calculated for the period from 2001 to 2020, increased in comparison with the climatic norm for 1971-2000 by 3-6%. This is an indicator of an increase in climate aridity during its current warming. As a result, high rates of dehumification (decrease in the relative humus content by 21-35%) and changes in the structural state of the arable layer and grain size distribution (decrease in water-resistant aggregates >0.25 mm from 39 to 31.8% and the absolute content of physical clay by 7.5%). At the same time, there is an increase in the mineralization of groundwater from 2500 to 7000 mg/l, as well as an increase in the content of toxic salts in the soil solution. Thus, the content of Cl—, SO42— ions in the places of replenishment with groundwater increased from 0.27 to 0.56 mg/eq. and from 0.27 to 13.27 mg/eq. respectively. The cation values also increased: Ca2+ – from 0.30 to 4.41 mg/eq., Mg2+ – from 0.12 to 5.59 mg/eq., The sum of K+ and Na+ – from 0.09 to 0.28 mg/eq. In the lowered elements of the relief, the development of processes of local salinization and waterlogging is noted.
Keywords.Climate change, aridization, drought, degradation, salinization.
Financing. The article was made within the state assignment No. 0751-2019-0008 “To develop theoretical foundations for structuring agricultural landscapes, adapting them to climatic and geomorphometric features of the territory in order to preserve and optimize the use of land resources to obtain an economically reasonable level of quality agricultural products”.
UDC 633.2.033; 633.2.032; 633.2.038
Dinarvand M., Arami S.A., Sarab S.A.M. EVALUATION OF CHANGES IN NATIVE VEGETATION COVER OF DUST SOURCES IN THE SOUTHWEST OF IRAN UNDER DIFFERENT IRRIGATION SYSTEMS AND RAINFALL PATTERNS IN SEEDLING CULTIVATION AREAS // Arid ecosystems. 2022. V.28. № 1 (90). P. 28-41.
Recieved September 3, 2021. After revision October 14, 2021. Accepted October 15, 2021.
Efficient use of rainfall and water storage has fundamental importance for rehabilitation and improving rangelands in arid areas. In this study, we evaluated the changes in the natural vegetation cover of three regions (dust centers) of the south and southeast of Ahvaz under different irrigation systems and rainfall patterns following seedling cultivation. Observations were made on five 100-meter transects, each 50 meters apart, which were systematically established in the three selected areas. Around 180 fixed plots were installed along transects. In the two growing seasons of spring and autumn from 2018 to 2020, the coverage of native species was recorded. The Simpson and Shannon and dominance diversity indices were estimated using the PAST software. The results showed that in the selected areas, various irrigation methods along with rainfall caused significant positive changes in vegetation cover, the number of species, and diversity from 2018 to 2020. The results indicated a significant difference between the average dominance index, Simpson and Shannon indices, and vegetation cover, as well as the number of species in different years. This study has identified that due to the lack of water for surface irrigation, contour furrowing and pitting using an excavator is the best and cost-effective way to restore native species. In addition to creating a suitable hole for receiving irrigation water, this method provides better drainage of the area during the rainy season, providing a suitable substrate for the growth and germination of seeds of native plants.
Keywords: Khuzestan province, furrow, Shannon, Simpson, species diversity.
Financing. This article is taken from a research project “Evaluation the change of vegetation in a cultivated area of dust sources of Khuzestan province using of satellite images and field data” and its research sponsor is the Forest and Rangeland Research Institute of Iran (Project No. 2-46-09-018-000216).
Zalibekov Z.G., Mamaev S.A., Biarslanov A.B., Kurbanismailova A.S. SOILS OF ARID REGIONS OF SOUTHERN RUSSIA IN THE BASIC CLASSIFICATION OF SOILS OF THE WORLD // Arid ecosystems. 2022. V.28. № 1 (90). P. 42-52.
Received April 24, 2020. After revision October 14, 2020. Accepted August 16, 2021.
Soil cartographic studies and preparation of soil maps are carried out using classification and diagnostics of soils, as well as various methodological approaches. The most acceptable in modern conditions are «Classification and diagnostics of soils of Russia» (2004), the main difference of which is the use of the principles of substantive genetic classification developed by V.M. Friedland. To further develop this classification, an attempt has been made to determine the classification position and properties of arid soils subjected to desertification, aridization. An important criterion determining the acceptability of the new approach is the allocation of supertype subdivisions (trunks – synlithogenic, postlithogenic organomineral soils) characteristic of highly degraded soils in the foci of desertification. Desertification, as a natural-anthropogenic process, leads to the loss of humus horizons and the emergence of a soil-forming geological rock on the surface. At the same time, the properties of soils at the highest supertype level change with the transition of postlitogenic to synlitogenic organomineral soils.
Taking into account the global nature of the manifestation of desertification, the control of changes is a prerequisite for determining the place of arid soils of the southern regions of Russia in the basic classification of soils of the world. The proposed article provides a theoretical justification for the classification differences allocated to supplement with diagnostics, a nomenclature of properties with an appropriate sequence.
Keywords: basic classification, substantive genetic classification, arid soils, synlithogenic variety, postlithogenic variety, halomorphic desertification, ferrallite formations, erosion, salinization, dehumification.
Financing. The work was carried out within the framework of the State Assignment of the Institute of Geology of the Dagestan Federal Research Center of the Russian Academy of Sciences “Landscape-geochemical zoning of the Caspian lowland”, Section 1, No. AAA-A117-117021310199-9 “Development of methodological foundations for studying the humus state and soil salinization for the purpose of landscape-geochemical zoning of arid territories”, Topic 3, No. AAAAA-A17-117021310203-3 “Ecological and geochemical features of groundwater of the North-Eastern Caucasus (Dagestan). Natural and anthropogenic pollution factors”.
Pankova E.I., Golovanov D.L., Yamnova I.A. A SERIA OF MEDIUM-SCALE NATURAL MAPS OF THE JIZZAKH STEPPE IN THE 70S OF THE XX CENTURY (BEFORE THE BEGINNING OF MELIORATIVE LANDUSE) // Arid ecosystems. 2022. V.28. № 1 (90). P. 53-64.
Received August 12, 2021. After revision September 1,2021. Accepted October 1, 2021.
The article considers the natural conditions of the Jizzakh steppe in the 70-80-ies of the XX century. During this period, we created a series of maps that reflected the natural diversity of the steppe before the beginning of its reclamation development. The series of cards includes: 1) map of lithological and geomorphological zoning, 2) soil map, 3) maps of salinity, 4) map of gypsum-bearing soils. All the listed maps were created on a topographic basis of M 1:100000 using aerial photography materials. On the territory of the Jizzakh steppe, 22 lithological-geomorphological regions were identified, united into 5 lithological-geomorphological regions. Within their limits, detailed soil-salt maps M 1:2000 were additionally compiled for key areas. A series of maps is a kind of geoinformation system that characterizes the state of the soil cover of the Jizzakh steppe before its development.
The article provides information about the soil features of the selected areas. It is shown that within the limits of lithological and geomorphological areas, the selected areas differed significantly before irrigation in the history of development, lithological structure, structure of soil cover, degree of salinity and gypsum content of soils, and, therefore, in their reclamation properties.
The analysis of the differences in the initial soil-reclamation state of the selected regions and districts will now allow for a more reliable assessment of the advantages and disadvantages of the reclamation measures carried out in different areas of the Jizzakh steppe, taking into account their natural features.
Keywords: salinization, gypsum content, geography, cartography, genesis and classification of arid soils.
Acknowledgement. We thank L.A. Gafurova, who, at our request, provided us with a list of recent works containing information about the current state of the soils of the Jizzakh steppe.
Financing. The work was carried out on the topic of the State Task of Research No. 0591-2019-0023 “To identify the features of soil salinization in different regions of Eastern Siberia and adjacent territories”.
UDC 631.1: 631.4:631.6:581.5: 528.7:528.8:574.46
Yuferev V.G., Tkachenko N.A., Sinel’nikova K.P. SPECTRAL CHARACTERISTICS OF DESERTIFICATED PASTURES OF BLACK LANDS (KALMYK REPUBLIC) // Arid ecosystems. 2022. V.28. № 1 (90). P. 65-72.
Received September 4, 2021. After revision October 13, 2021. Accepted October 14, 2021
Geosystems of the desert territories of Kalmykia in modern conditions function in conditions of increasing anthropogenic impact and intensity of negative weather events, including the impact of dust storms, which often leads to a significant decrease in pasture productivity, a decrease in the feed base and a significant reduction in livestock. In this regard, it is relevant to determine the spectral characteristics of desert pastures by ground methods, which provides not only the detection of the reflected energy distribution over the spectrum frequencies, which in itself is important for subsequent verification of remote sensing data of pastures, but also the possibility of obtaining the values of normalized indicators, both for plant communities and for specific plants and soil types with the formation of a spatial data base. The objects of the study are the natural phytocenoses of desert pastures of the Black Lands at the landfills: «Smushkovo»,» Molodezhny»,»Privolny»,» Dl. Sagi»and» Tavn-Gashun». Geobotanical and spectrometric studies were carried out at these polygons and spatially determined data on the spectral characteristics of plant communities were obtained. Spectrometric studies of phytocenoses are carried out to assess their condition on the basis of spectrosonal surveys, both ground-based and remote. To present the results of the assessment of the spectrometric characteristics of the vegetation cover of the downed pastures: the predominant communities at the landfill and «Tavn-Gashun» were selected: bluegrass with Descurania sofia (Poa bulbosa+Descurainia sophia) with a projective cover of 45%, grasshopper bluegrass (Poa bulbosa-Stipa capillata) – with a projective cover of 40% and open soil (slightly humus sand). The studies were carried out using the PSR-1100 field spectroradiometer. The results of studies of the spectrum of reflected radiation of plant communities and underlying soils allowed us to establish the characteristic features of the distribution of reflected and absorbed energy, to compile a catalog of individual spectra and normalized indicators for them. Individual spectral characteristics were established for the phytocenosis Poa bulbosa+Descurainia sophia, the average value of reflected energy in all spectral ranges is 20.2 MW/(m2×sr×nm), the standard deviation of reflected energy is 9.90, the vegetation index NDVI = 0.208, for Stipa capillata, the average value of reflected energy in all spectral ranges is 20.5 MW/(m2 sr nm), the standard deviation of reflected energy is 12.36, the vegetation index NDVI = 0.316, for Calligonum aphyllum, the average value of reflected energy-the reflected energy in all spectral ranges is 47.2 MW/(m2×sr×nm), the standard deviation of reflected energy is 9.81, the vegetation index NDVI = 0.354. For soil, the average value of reflected energy in all spectral ranges is 30.3 MW/(m2×sr×nm), the standard deviation of reflected energy is 9.28, the vegetation index NDVI = 0.106. The highest average value of NDVI was noted for Calligonum aphyllum.
Keywords: geosystem, analysis, desertification, degradation, spectrometry, satellite images, phytocenoses, verification, vegetation indices, albedo.
Financing. The work was carried out within the framework of the State Task of the Federal Research Center of Agroecology of the Russian Academy of Sciences No. 0713-2019-0001 “To conduct theoretical and geoinformation modeling, monitoring, forecasting of degradation processes of components of agroforestry landscapes based on aerospace research in forest-steppe, steppe and desert zones and to develop ways to manage anti-degradation agroforestry technologies to prevent desertification of lands, increase their fertility and form an ecological framework” (state registration No. AAAAAA-A-116122010038-9).
Rygalova N.V., Bykov N.I., Shigimaga A.A. RADIAL GROWTH OF WOODY PLANTS IN EXTRAZONAL AND ANTHROPOGENIC LANDSCAPES OF THE DRY STEPPE OF THE WEST SIBERIAN PLAIN // Arid ecosystems. 2022. V.28. № 1 (90). P. 73-79.
Received September 3, 2021. After revision October 4, 2021. Accepted October 10, 2021
The article presents dendroclimatic analysis of tree-ring chronologies of coniferous (Pinus sylvestris L., Larix sibirica Ledeb.) and deciduous (Betula pendula Roth., Populus balsamifera L.) tree species growing in natural extrazonal landscapes of pine belt forests and natural-anthropogenic landscapes of shelterbelt forests in the dry steppe subzone of southern Western Siberia. The maximum annual growth was recorded for poplar, the minimum – for larch. The greatest climatic sensitivity is characterized by rows of radial growth of trees in shelterbelt forests (maximum values were recorded for birch). The similarity of tree-ring rows of birch and larch, which are most susceptible to water stress under dry steppe conditions, was noted. The significance of hydrothermal conditions of August-September of the previous year, as well as May (for conifers) and, mainly, June (for deciduous species) of the current year was established. Positive statistically significant relationship was noted with precipitation and moisture index of the territory (Selyaninov’s hydrothermal coefficient), with temperature – negative. For pine chronologies of natural pine belt forests, the contribution of the first component determines 80.6% of the variability of the series, which is greater than for the chronologies of shelterbelt forests. This indicates a mixed natural-anthropogenic signal in the annual rings of trees of cultivated forest plantations.
Keywords: dry steppe, tree-ring chronology, dendroclimatic analysis, pine belt forests, shelterbelt forests, Scots pine, Siberian larch, birch, Balsam poplar.
Financing. The work was carried out with the support of the RFBR (project No. 19-45-220011 p_a, “Response of protective forest strips of the dry-steppe zone of the Altai Territory to climate change”) and within the framework of the state assignment of the Institute of Water and Environmental Problems SB RAS (state registration No. 0306-2021-0007, “Natural and natural-economic systems of Siberia in the conditions of modern challenges: diagnostics of conditions, adaptive capabilities, potential of ecosystem services”).
UDC 574.472; 581.524.41
Dikareva T.V., Rumyantsev V.Yu., Soldatov M.S., Malkhazova S.M. DANGEROUS TO PUBLIC HEALTH PLANTS IN ARID AND SEMIARID BIOMES OF RUSSIA // Arid ecosystems. 2022. V.28. № 1 (90). P. 80-90.
Received April 9, 2021. After revision May 1, 2021. Accepted October 1, 2021
The list of species of allergenic and poisonous plants in arid and semiarid biomes of Russia is under consideration in the paper. The species diversity of allergenic and poisonous plants as a whole is considered. Statistical analysis of correlation between number of allergenic and poisonous plants species in the regional biomes and climatic indices has been made. The sketch maps have been done and their analysis has been made. It can be assumed that number of allergenic and poisonous plants in certain biome is correlated with the total number of species in that biome, meanwhile it is conditioned by geographical position that is linked with annual temperature and precipitation in the region. The closest connection is detected between the number of allergenic and poisonous plants species and average annual temperatures. Comparatively close connection is detected between number of species and average annual precipitation. Nevertheless, connection of total number of allergenic and poisonous plants in biomes with their aridity appeared to be weak.
Key words: allergenic and poisonous plants, arid and semiarid biomes, climatic indices, correlation analysis.
Financing. The article was written within the state assignment No. TSITIS 121051100137-4 of Moscow State University “Spatio-temporal organization of ecosystems in the conditions of environmental changes”.
UDC 581.5+581.14 (575.13)
Saribaeva Sh.U., Shomurodov H.F., Abduraimov O.S. ONTOGENESIS AND ONTOGENETIC STRUCTURE OF COENOPOPULATIONS OF THE ASTRAGALUS HOLARGYREUS BUNGE (FABACEAE), NARROW-LOCALITY ENDEMIC OF KYZYLKUM // Arid ecosystems. 2022. V.28. № 1 (90). P. 91-97.
Received July 20, 2021. After revision Octopber 15, 2021. Accepted October 20, 2021
Analysis of the current state of the narrow-local endemic of the Kyzylkum Astragalus holargyreus showed that the studied coenopopulations are normal and incomplete. The study showed coenopopulations of A. holargyreus are normal and incomplete. The age spectrum of the first coenopopulation responds to the characteristic spectrum and reflects the biological features of the species: a gradual increase in life expectancy in the juvenile fraction and generative periods with a culmination in the middle-aged state, rapid aging. The ontogenetic spectrum in the second coenopopulation does not coincide with the characteristic spectrum. According to the amount of the points of organism and population signs, all the examined coenopopulations are in a stable state.
Keywords: ontogenesis, Kyzylkum desert, Astragalus holargyreus, Bukantau range, ontogenetic structure, coenopopulation.
Financing. The work was carried out with the support of the project of the Ministry of Innovation of the Republic of Uzbekistan, scientific project No. P3-2014-0828163420 “Assessment of the state of coenopopulations of rare and endangered plant species of the remnant lowlands of Kyzylkum in connection with desertification”.
UDC 574.2:582.998.2 (470.67)
Semenova V.V., Anatov D.M. ACCUMULATION OF HEAVY METALS BY PLANTS OF THE GENUS ACHILLEA L. IN THE ARID CONDITIONS OF THE PLAIN ZONE OF DAGESTAN // Arid ecosystems. 2022. V.28. № 1 (90). P. 98-105.
Received September 8, 2021. After revisiou September 15, 2021. Accepted October 11, 2021
In the flat zone of Dagestan, arid mixed grasses steppes are common. As part of their herbage, yarrow plants are present, forming extensive thickets in the lowlands. For the first time in Dagestan, the accumulation of heavy metals in the organs of plants of the genus Achillea L. and in soils was studied. The content of Fe, Mn, Pb, Cd in the aboveground and underground mass of plants of the genus Achillea L. was determined in natural and anthropogenic disturbed areas, as well as in the soils on which they grow. It has been established that the accumulation and distribution of heavy metals in plant organs is influenced by pollution from motor vehicles. In Achillea nobilis plants selected in Uchkent and Stalskoye villages, the cadmium content exceeds the maximum permissible level by 1.2-1.7 times. According to the calculated coefficients of biogeochemical mobility, it was revealed that plants of anthropogenically disturbed habitats are characterized by a high accumulation of Fe, Cd, but low – Mn, Pb.
Keywords: Achillea millefolium L., Achillea nobilis L., Achillea biebersteinii Afan., heavy metals, aboveground and underground mass of plants, soil, pollution.
Financing. This work was carried out in the Laboratory of Soil and Plant Resources of the Caspian Institute of Biological Resources of the Russian Academy of Sciences, state assignment No. 0205-2016-0003 “Dynamics of Soil Cover and Ecosystems Bioproductivity in the Northwestern Caspian Region and Eastern Caucasus” (state registration No. АААА-А17-117081640024-6), and it was also funded by the Program of the Russian Academy of Sciences Presidium, No. 1.21 “Biological diversity of natural systems. Biological Resources of Russia: Assessment of their condition and basics of Monitoring”.
UDC 631.95: 631.6.02
Vilkova V.V., Kazeev K.Sh., Shkhapatsev A.K., Kolesnikov S.I. RESPONSE OF ENZYME ACTIVITY OF ARID FOREST SOILS OF THE BLACK SEA COAST OF THE CAUCASUS TO PYROGENIC EFFECTS // Arid ecosystems. 2022. V.28. № 1 (90). P. 106-113.
Received July 15, 2021. After revision September 7, 2021. Accepted October 1, 2021.
In recent years, the spread of wildfires in Russia and the world has increased. Fires have a catastrophic impact on forest ecosystems, as well as a significant impact on the biota and biological activity of soils. The enzyme activity of arid forest Cambisol of the Black Sea coast of the Caucasus after exposure to fires has been evaluated. The study area is located on the Abraus Peninsula of the Black Sea coast of Russia in the state nature reserve «Utrish». The xerophytic forests and woodlands common here consist of various types of junipers, oaks, pistachios and other species, the soil cover is represented by a Cambisol combination of varying degrees of thickness, stony, carbonate and humus. The studied post-pyrogenic sites differ by a different recovery period (0-11 years). Soil samples were taken from three different depths (0-3, 3-10 and 20-30 cm) in three-fold repetition. A significant long-term effect of fires on the activity of enzymes (catalase, invertase, peroxidase, urease) in subtropical Cambisol has been shown. The content of organic carbon in the surface horizon immediately after a fire increases due to the accumulation of pyrogenic carbon of ash and soot on the soil surface. A year after the fire, the carbon content in the soils decreases by 47%, and after 11 years it approaches the control values. The activity of catalase, urease and phosphatase of post-pyrogenic Cambisol immediately after the fire was reduced by 43-69% compared to the soil of the control site. The activity of peroxidase, on the contrary, was stimulated by fire. In the future, the degree of inactivation of enzymes and changes in the organic carbon content in post-pyrogenic soils depended on the time of post-pyrogenic restoration of ecosystems and the type of enzyme. The peculiarities of changes in the activity of enzymes during the restoration of post-pyrogenic Cambisol were revealed. The complete restoration of the enzymatic activity of post-pyrogenic Cambisol did not occur even 11 years after the fire. A change in the correlations of enzyme activity and the content of organic carbon in the soil in post-pyrogenic Cambisol of different ages has been established.
Keywords: soil enzymes, pyrogenic effect, wildfires, bioindication.
Acknowledgements. The authors express their gratitude to O.N. Bykhalova, the deputy director for scientific work of the “Utrish” State Nature Reserve, for allowing us to carry out the research on the territory of the reserve.
Financing. The study was carried out with the state support of the leading scientific school of the Russian Federation “Agroecological state of soils under various anthropogenic influences” (NSH-2511.2020.11).
Vlasenko M.V., Trubakova K. Yu. FEATURES OF THE SEASONAL DYNAMICS OF THE STRUCTURE OF PHYTOCENOSES ON THE SANDY LANDS OF THE SOUTH OF THE EUROPEAN TERRITORY OF RUSSIA // Arid ecosystems. 2022. V.28. № 1 (90). P. 114-123.
Received August 18, 2021. After revision October 1, 2021. Accepted October 10, 2021.
Species diversity, yield, share participation and seasonal variability of species in natural and artificially created phytocenoses in the sandy lands of the southern European territory of Russia are considered. The role of the influence of moisture conditions on the formation of species diversity in different communities is explained. The Tsimlyansk sand massif was monitored using the methods of ecological and geobotanical surveys. It is established that the main mass in the phytocenoses of the Tsimlyansk sand massif is occupied by species from the family Asteraceae, Fabaceae and Poaceae. The herbaceous-shrub layer includes 183 species from 41 families. The Simpson index shows that for the territory of excessive moisture (II), the dominance of species of the Poaceae family is most pronounced. In areas of sufficient and variable moisture (III), moderate moisture (IV), as well as in areas of insufficient complex moisture and complex severely insufficient moisture under the sandy hillocks and moderate moisture in the grove and eroded sands (V), species of the Asteraceae, Fabaceae and Poaceae families dominate. The index of similarity of the species composition of the Jacquard shows that the most similar in terms of species diversity of the territory are: complex insufficient (Va) and complex severely insufficient moisture under the sandy hillocks and moderate moisture in the grove and eroded sands (Vb) – 90%; moderate moisture (IV) and complex severely insufficient moisture under the sandy hillocks and moderate moisture in the grove and eroded sands (Vb) – 89%; sufficient and variable moisture (III) and moderate moisture (IV) – 87%; excessive moisture (II) and moderate moisture (IV) – 87%. In the territory of moderate moisture (IV) in the studied phytocenosis, the largest mass was formed by cereals: Agropyron cristatum L., A. elongatum (Host) P. Beauv., Festuca valesiaca Gaudin, F. beckeri (Hack.) Trautv. and Poa pratensis L., Artemisia campestris L. and Galium verum L. predominated in various grasses. On average, the share of cereals in the community was 66.5%, the share of mixed grasses was 33.5%. In the territory of sufficient and variable moisture (III), the largest phytomass was also formed by species from the Poaceae family: Elytrigia repens (L.) Nevski and Agropyron elongatum (Host) P. Beauv., Agropyron cristatum L., Artemisia campestris L., Artemisia vulgaris L. and Artemisia arenaria DC had a great influence on the growth of phytomass. To stop the processes of degradation, improve the economic condition and increase the fertility of pasture ecosystems in large areas, it is proposed to fix mobile sands and restore pastures with the help of selected multicomponent grass mixtures. The experiment on studying the productivity of artificially created phytocenoses for restoring and increasing the productivity of natural pasture ecosystems was carried out on the vegetation sites of the lysimetric complex of the Federal Research Center of Agroecology of the Russian Academy of Sciences. The most promising on sandy substrates is a grass mixture with Agropyron cristatum L., Artemisia arenaria D.C., Medicaga sativa L. and a yield of 228.6-246.7 g/m2, as well as a grass mixture with Agropyron cristatum L., Agropyrom elangatum Host.P.B., Bromus inermis Leyss. and a yield of 184.4 g/m2.
Keywords: phytocenoses, species diversity, sand massifs, pasture ecosystems.
Financing. The work was carried out within the research No. AAAA19-119042290014-5 “Theoretical foundations of water resources management in the forest-agrarian development of arid territories of the Russian Federation on the basis of a dynamic model of the water balance of the region, mathematical modeling of the processes of formation and dynamics of groundwater and surface waters, assessment of the impact of climate change and anthropogenic loads on the agro-resource potential and forest-growing conditions”.
UDC 631.95: 631.6.02
Belyakov A.M., Koshelev A.V., Nazarova M.V. METHOD OF ASSESSMENT OF ECOLOGICAL BALANCE IN THE AGROLANDSCAPES OF THE DRY-STEPPE ZONE OF CHESTNUT SOILS OF THE VOLGOGRAD REGION // Arid ecosystems. 2022. V.28. № 1 (90). P. 124-130.
Received July 13, 2021. After revision August 8, 2021. Accepted October 12, 2021.
The agrolandscapes of the dry-steppe zone of chestnut soils in the middle reaches of the Don River and the lower reaches of the Volga River function in harsh soil and climatic conditions with a moisture deficit of 30-40% and are currently undergoing intensive anthropogenic use, which, according to many researchers, is the reason for their imbalance and varying degrees of degradation. In this regard, the procedure for agroecological monitoring and the system for assessing the ecological balance of agrolandscapes, including the method for its implementation, acquire special scientific and practical importance in the formation of rational land use in areas of insufficient moisture. As a result of the research, new knowledge has been obtained about the processes occurring in the agrolandscapes of the dry-steppe zone of chestnut soils under the influence of cultivation techniques, agricultural technologies and methods of using land resources. A significant influence of agrotechnological factors on the ecological balance of agrolandscapes are identified, such as the structure of sowing, crop rotation, methods of basic tillage, the level of alienation of nutrients, the rates of fertilization, a protective complex of agrophytocenoses, the method of arrangement and forest cover of land use, systemic measures of anti-erosion protection of the territory and which can lead to the object of research to a high degree of ecological balance or, conversely, to its degradation. A method for assessing the ecological balance of agrolandscapes in the dry-steppe zone of chestnut soils has been developed and proposed for practical use by a point system based on ten indicators. On the basis of the presented method, the agrolandscape is assessed in points on a balance scale: 5 points (absolutely balanced), 4 points (balanced), 3 points (medium balanced), 2 points (poorly balanced), 1 point or less (not balanced). The developed system of criteria and method for ecological assessment allows a high degree of objective assessment of the ecological balance of the agrolandscape of the dry-steppe zone of chestnut soils, which can be used as the basis for making organizational and technological decisions and measures to restore of the ecological balance of the territories of the southern provinces of the Russian Federation and the regulation of anthropogenic load on agrosphere in the conditions of insufficient moisture.
Keywords: agrolandscapes, factors of influence, agricultural technologies, ecological balance, system of assessment indicators, assessment method.
Financing. The work was carried out within the state assignment No. 0713-2019-0007 of the Federal Research Center for Agroecology of the Russian Academy of Sciences “To develop conceptual, methodological and information technology bases for the formation of ecologically balanced agroforestry landscapes and adaptive farming systems using new generation chemicals for precision production of crop products while preserving and reproducing soil fertility and efficient use of natural resource potential”.
UDC 597.552.512; 57.022
Rabazanov N.I., Barkhalov R.M., Rabazanov R.N., Markevich G.N. THE STATE OF THE EISENAM TROUT POPULATION (SALMO TRUTTA EZENAMI BERG, 1948) AND THE FORECAST OF THE DEVELOPMENT OF THE ECOLOGICAL SITUATION IN LAKE KEZENOI-AM // Arid ecosystems. 2022. V.28. № 1 (90). P. 131-139.
Received July 20, 2021. After revision August 1, 2021. Accepted October 1, 2021.
Based on the literature data and our own materials, the development of the ecosystem of Lake Kezenoy Am (Ezynam) over the past 100 years is described. It is shown that the ecosystem underwent a catastrophic transformation as a result of the introduction of chub (Squalius cephalus orientalis Linnaeus, 1758) in the middle of the XX century and perch (Perca fluviatilis Linnaeus, 1758) in 2013-2014. According to the trapping we conducted and the survey data we collected, the endemic subspecies of trout (Salmo trutta ezenami Berg, 1948), previously represented by two sympatric forms with lake and stream spawning, has almost completely disappeared in the ecosystem. An additional factor in the degradation of the ecosystem was the greatly increased intensity of net fishing. In modern conditions, the pond is dominated by perch, a subdominant species-chub. Native fish species are currently displaced to the periphery of the ecosystem: the Terek gudgeon (Gobio holurus Folwler, 1976) is found only in the lower reaches of the tributaries, the Eisenam trout in the basin of the lake has disappeared completely and is presumably found only in the upper reaches of the tributaries. Based on the analysis of the literature data on the transformation of similar ecosystems, it can be argued that the consequences of the degradation of the fauna of Lake Kezenoy Am are irreversible, and in the coming years there will be a complete disappearance of the Red Data Book Eisenam trout. Urgent measures are required to preserve the endemic species, including artificial trout breeding and reclamation measures to reduce the number of introduced species.
Keywords: Lake Kezenoy-Am, ichthyofauna, Eisenam trout, population status, conservation measures, river perch, chub
Acknowledgements. The authors are grateful to the administration of the recreational complex “Kezenoy”, which provided us with full technical support at the worksite.
Financing. This research was carried out within the state assignment No. АААА-А19-0101590064-1 “Resource Potential and Structure of Game-Fish Populations, Modern Trends of the Ecosystems Dynamics in the Dagestan Region of the Caspian Sea, and Patterns of Their Formation”, and it was also partially supported by the Russian Foundation for Basic Research, Grant No. 16-04-01687 “Stable Food Diversification of the Salvelinus (Salmonidae) Loaches in Littoral Ecosystems: an Individual Specialization, or a New Round of the Microevolutionary Process?”.