Архив метки: density

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

Arid Ecosystems

UDC 58.009:582.948.25

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

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

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

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

DOI: OWOUIU

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

INFLUENCE OF AGGREGATION OF CHESTNUT AND MEADOW-CHESTNUT SOILS ON THEIR AGROPHYSICAL PROPERTIES IN THE TERSKO-SULAK PLAIN

Arid Ecosystems

Teymurov S.A., Imashova S.N., Ramazanov A.V. INFLUENCE OF AGGREGATION OF CHESTNUT AND MEADOW-CHESTNUT SOILS ON THEIR AGROPHYSICAL PROPERTIES IN THE TERSKO-SULAK PLAIN // Arid ecosystems. 2021. V.27. № 3 (88). P. 89-95.

The data of studying the physical properties of chestnut and meadow-chestnut soils are considered. The dependence of the density of the studied soils on both the size of aggregates and the features of the soil formation process is shown. In each particular case, this dependence is closely related to the genesis of soils and the peculiarities of their agricultural use. When considering the porosity of aggregates, estimated by the percentage of fractions, it is seen that the main share of interaggregate porosity in the studied soils is accounted for by large aggregates. The results of the obtained studies can be extrapolated to other areas of the soil cover of the studied area.

Keywords: soil structure, aggregate, density, porosity, genetic horizon.

Funding. This work was carried out within the state assignment No. 0733-2015-0002 “To Develop Methods of Fertilizers Usage (Green Manure, Straw, Manure) to Increase Soil Fertility and Corn Yield for its Grain and Grain Sorghum under the Irrigation of the Terek-Sulak Subprovince”.

DOI: 10.24411/1993-3916-2021-10168