Архив метки: droughts

REGIONAL CLIMATE CHANGES IN DRY STEPPES AND THEIR CONNECTION TO DROUGHTS

Arid Ecosystems

UDC 551.583:632.125

Pugacheva A.M., Belyaev A.I., Trubakova K.Yu., Romadina O.D. Regional Climate Changes in Dry Steppes and their Connection to Droughts // Arid Ecosystems. 2022. Vol. 28. № 4 (93). P. 13-21. | PDF

The authors carried out an analysis of the regional climate for separate administrative districts of the Volgograd region for the first time. Differences were revealed based on temperature data and incoming precipitation. The study of the Volgograd region in the context of natural and climatic zones and subzones is of particular interest. This makes it possible to analyze multidirectional trends of climate change in a limited area. The open data of the climatic archive (VNIIGMI-MCD) on 5 reference weather stations of the region located in the dry steppes of chestnut soils were used in the work. The droughts were calculated on the basis of temperature and precipitation anomalies using Pedj Drought Index. Regional changes in the climate were identified in terms of the flow of precipitation during the seasons of active vegetation (spring, summer) according to long-term time series of data from registered meteorological stations. Regression analysis showed an increase in their reception in the spring and a decrease in the summer. Also, an increase in the number of droughts in the summer period was revealed with a decrease in aridity. This effect increases the intensity using Pedj Drought Index, the value of which reaches 3 units. A slight inverse correlation was found between the amount of incoming precipitation and the number of droughts in the summer in Volgograd, Surovikinsky, Ilovlinsky and Kamyshinsky districts and dry phenomena in the Surovikinsky district, as well as a direct moderate dependence on droughts in the Kamyshinsky district in summer. Areas with the maximum number of drought events have been identified, therefore, having the maximum risks of agricultural production. In Kamyshinsky district there were 21 drought events in spring, 115 in summer and in Surovikinsky district there were 4 drought events in spring, 70 in summer. In accordance with the results obtained, especially in the regions most susceptible to the influence of droughts, it is necessary to adjust the existing crop rotation schemes, the range of cultivated crops and a shift in emphasis towards conducting reclamation agriculture in these territories in order to eliminate the risks of agricultural production with the effective use of land resources. Regional climate studies are necessary for conducting effective agricultural activities. This makes it possible to objectively assess the situation with climate change at the level of administrative districts. The information obtained is necessary for the purpose of making managerial, risk-free decisions for agricultural production for agricultural regions.

Keywords: climate change, seasons of active vegetation, moisture availability during the seasons of active vegetation, droughts, aridity, dry steppe, chestnut soils.

Acknowledgements. The authors are grateful to the research engineer of the Laboratory of Geoinformation Modeling and Mapping of Agroforestry Landscapes of the Federal Research Center of Agroecology of the Russian Academy of Sciences A.A. Vasilchenko for the cartographic material prepared for the article.

Funding.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 «Theoretical foundations of the functioning and natural-anthropogenic transformation of agroforestry complexes in transitional natural-geographical zones, patterns and forecast of their degradation and desertification based on geoinformation technologies, aerospace methods and mathematical cartographic modeling in modern conditions».:

DOI: 10.24412/1993-3916-2022-4-13-21

EDN: ZNQHLZ

CHARACTERISTICS OF THE SPRING-SUMMER DROUGHTS DURING THE DRY AND WET PERIODS IN THE SOUTH OF EUROPEAN RUSSIA

Arid Ecosystems

Zolotokrylin A.N., Titkova T.B., Cherenkova E.A. CHARACTERISTICS OF THE SPRING-SUMMER DROUGHTS DURING THE DRY AND WET PERIODS IN THE SOUTH OF EUROPEAN RUSSIA // Arid ecosystems. 2020. V. 26. № 4 (85). P. 76-83. | PDF

Distribution patterns of spring and summer droughts characteristics during high and low annual humidification periods are studied in twelve federal subjects of the South of European Russia for the period 1901-2018. During this time, four periods of different humidification conditions (alternate more humid, dry, humid and again dry periods) with variable durations are observed through data on anomalies of the aridity index in seven regions: Kursk, Belgorod, Voronezh, Saratov, Volgograd, Rostov Oblasts and the Republic of Kalmykia. The draining period was noted in Samara and Astrakhan Oblasts from the beginning of 20th century until its middle. Then the draining period changed to more humid. The most frequent change of periods with different humidification conditions was observed in Stavropol Krai, where five alternate periods were distinguished. It was found that the frequency of spring and summer droughts is consistent with the long-period humidification conditions. According to data of the Standardized Precipitation Index (SPI), it increases during the dry period by an average of 1.5 times while the intensity of droughts rises insignificantly. The increased humidification conditions observed in every above-mentioned federal subject in the second half of the 20th century changed to drier conditions in the beginning of the 21st century. The spreading of drier conditions began from east regions. The development of the dry period of humidification in the 21st century is confirmed by a distribution of a negative NDVI trend throughout the territory. While the aridization trends are not statistically significant in the regions of the South of European Russia in more than a century, there are prolonged interdecadal periods of aridizational strengthening and weakening, which are characterized by significant differences in frequency and intensity of spring and summer droughts.

Keywords: humidification periods, aridization, aridity index, droughts, SPI, NDVI.

DOI: 10.24411/1993-3916-2020-10121