Архив метки: steppe

STABILITY OF PHYTOMASS DYNAMICS IN PROTECTED LOW MOUNTAIN-STEPPE LANDSCAPES AND PASTURES IN THE SOUTHERN URALS

Arid Ecosystems

UDC 911.2 (470.56)

Khoroshev A.V. STABILITY OF PHYTOMASS DYNAMICS IN PROTECTED LOW MOUNTAIN-STEPPE LANDSCAPES AND PASTURES IN THE SOUTHERN URALS // Arid ecosystems. 2022. V.28. № 3 (92). P. 3-13. | PDF

In the steppe zone, the high sensitivity of the vegetation cover to humidification contrasts raises the question of the dependence of the intraseasonal dynamics of phytomass on the spatial pattern of vegetation cover and relief in a landscape. We performed a case study in the Aituarskaya steppe (Orenburg region) to test the hypothesis about the inequality of the spatial factors of variability of functioning under the conditions of the reserve regime and pasture impact. Based on the frequency of occurrence of five gradations of deviations of the intraseasonal increments of the vegetation index NDVI from the mean values, the measure of instability of the types of dynamics of green phytomass (Shannon’s index) was calculated. The relationship between the types of dynamics and the types of natural boundaries, due to belonging to the relief forms with the characteristic types of phytocenoses, has been established. Areas of the most unstable phytoproductive functioning are characteristic of valleys with meadow steppes. The reserve regime stabilizes the dynamics of phytomass due to a higher subordination to landscape-scale climatic processes. On grazed areas, frequent changes in the variants of phytomass increments are more characteristic and dependence on local factors (e.g., stoniness, groundwater level) increases. In the pasture area, in some places, the dominant dynamics becomes with an intensive late spring accumulation of phytomass and a small decrease or renewal by the end of summer due to an increase in the proportion of non-palatable and grazing-resistant species.

Keywords: steppe, landscape, reserve, pasture, phytomass, NDVI, seasonal dynamics, stability, relief, Urals.

Acknowledgements. Expressing gratitude to D.E. Sharova, O.M. Podgorny, I.V. Volovinsky, G.M. Leonova for participation in field research and arrangement of remote materials and to reviewers for constructive comments.

Financing. The study was carried out with the financial support of the Russian Foundation for Basic Research, project No. 20-05-00464 «Spatial structure as a factor of stability of landscape functioning», 2020-2022.

DOI: 10.24412/1993-3916-2022-3-3-13

USE OF HOLOCENE DEPOSITS OF THE SOUTH-EAST ROSTOV REGION TO ESTABLISH THE ANCIENT ANTHROPOGENIC ACTIVITY IN STEPPE REGIONS

Arid Ecosystems

UDC 550.4; 551.8 (925.22)

Idrisov I.A.,  Shishlina N.I. USE OF HOLOCENE DEPOSITS OF THE SOUTH-EAST ROSTOV REGION TO ESTABLISH THE ANCIENT ANTHROPOGENIC ACTIVITY IN STEPPE REGIONS // Arid ecosystems. 2022. V.28. № 3 (92). P. 107-116. | PDF

Study of the beam system of the rivers Sal and  Don in the south-east of the Rostov region of Russia allowed us to establish a significant area of distribution and a wide variety of Holocene deposits. They accumulated depending on the local features of various sites, the features of exogenous processes, landforms, the nature of soil-forming rocks and other factors. As a result of the study, Holocene deposits in negative relief forms (in the floodplain and the first floodplain terrace) formed by alluvial and deluvial processes with a certain role of

aeolian processes were identified; Holocene sediments of the second floodplain terrace of the end of the Khvalynsky stage of the Caspian Sea and the Novoevksinsky stage of the Black Sea; the intermediate form is Holocene sediments in saucer-shaped depressions. The history of accumulation of deposits on negative and positive relief elements is due to the presence of contrasting stages of environmental changes. The revealed Holocene deposits of different ages were confined to archaeological artifacts that record short-term habitats of mobile cattle breeders of different eras. They were found near identified Holocene deposits. This makes it possible to identify and further study the «invisible» sites of ancient man and obtain additional data on the anthropogenic impact on steppe resource areas in antiquity.

Keywords: paleogeography, Holocene, beam, soil, steppe, River Don.

Financing. The study was supported by the Russian Science Foundation, grant No. 21-18-00026 «Resources and humans in the Bronze Age and the Middle Ages: the dynamics of the use of arid regions of southern Russia» (research supervisor N.I. Shishlin).

DOI: 10.24412/1993-3916-2022-3-107-116

PRESERVED STEPPED AREAS AS A BASIS FOR THE FUTURE ECOLOGICAL FRAMEWORK OF BELGOROD REGION

Arid Ecosystems

Tishkov A.A., Belonovskaya E.A., Zolotukhin N.I., Titova S.V.,  Tsarevskaya N.G.,  Chendev Y.G. PRESERVED STEPPED AREAS AS A BASIS FOR THE FUTURE ECOLOGICAL FRAMEWORK OF BELGOROD REGION // Arid ecosystems. 2020. V. 26. № 1 (82). P. 43-53 . | PDF

Belgorod Oblast is a region of ancient economic development with the highest level of agricultural land use in Russia and, accordingly, anthropogenic transformation of zonal vegetation and black soils. Despite all the efforts during the recent years to improve the territorial protection of nature in the region, all categories of protected areas occupy only 1.8% of the territory, which is one of the lowest rates among the subjects of the Russian Federation. Steppe areas in protected areas occupy less than 10% of the area of all protected areas, i.e. 0.2% of the area of the region, which can’t serve as a basis for the conservation of steppe biodiversity and the formation of the ecological framework of the region, where the zonal type of vegetation − steppe. The article presents a historical analysis of the transformation of steppe vegetation in the region, the results of the inventory using remote sensing of the remaining areas of the steppes, assessing the potential of their flora for the development of secondary successions, effective for the conservation of steppe biodiversity of the regional network of protected areas and the formation of ecological framework. It is shown that the identified 699 sites with preserved zonal steppe vegetation (about 39 thousand hectares), small-contour and fragmented, are located on the inconveniences and heavily eroded slopes of beams and dens. Without special measures, they are not able to become the basis of the ecological framework. Thus, we propose approaches and methods of stimulating restoration of steppes and man-made post-agrogenic soils of the region.

Keywords: steppe, forest-steppe, meadow, real and Cretaceous steppes, Belgorod Region, protected area, ecological framework, black soils, regenerative succession, succession system, Belogorie nature reserve.

DOI: 10.24411/1993-3916-2020-10082

SPATIAL-TEMPORAL DYNAMICS OF THE STATE OF MICROBIAL COMMUNITIES IN THE STEPPE SOILS OF THE VOLGA-DON INTERFLUVE

Arid Ecosystems

Demkina T.S. SPATIAL-TEMPORAL DYNAMICS OF THE STATE OF MICROBIAL COMMUNITIES IN THE STEPPE SOILS OF THE VOLGA-DON INTERFLUVE // Arid ecosystems. 2020. V. 26. № 1 (82). P. 76-83 . | PDF

Soil microorganisms are the essential part of soil composition. Almost every soil process depends on the microorganisms’ activity, in one way or another. That is why characteristic of microbial communities is one of the most important diagnostic indices representing the conditions for soil formation. Paleosols maintain some features from the moment of their burial, which can be found in some of the parameters of their microbial community, such as the active biomass of microorganisms, ecologic and trophic structure of community, oligotrophy index etc. We studied microbial communities from the soils of different ages and different natural areas of Volga-Don interfluve, to determine the patterns of their spatial-temporal changes in connection with the current conditions of soil formation. We found out that the characteristics of communities of the modern soils in the dry-steppe and deserted-steppe areas in the south-east of the East European Plain mostly determine the specificity of the local conditions for soil formation. Thus, the soils of one sub-class, while being under different geomorphological and landscape conditions, can vary in their microbiological parameters. Or the characteristics of microbial communities of different soils can be very close, if the latter are related to the similar reliefs, soil-forming rocks and ground water level. Conditions of those communities during different historical periods are mostly determined by the patterns of evolution of specific soil areal (landscape) and bioclimatic changes during the century. Therefore, the local specificity is formed under the dynamics of the microbial communities’ conditions and their structural and functional organization.

Keywords: steppe, chestnut and light chestnut soils of different ages, microbial communities.

DOI: 10.24411/1993-3916-2020-10086