Kuzmina Zh.V.,  Shinkarenko S.S., Solodovnikov D.A. MAIN DYNAMICS TRENDS OF THE FLOODPLAIN ECOSYSTEMS AND LANDSCAPES OF THE LOWER SYR DARYA IN THE CURRENTLY CHANGING ENVIRONMENT // Arid ecosystems. 2019. V. 25. № 4 (81). P. 16-29. | PDF

The Aral Sea catastrophe almost destroyed the sea. The construction of Kokaral Dam in 2005 made it possible to save the northern part of the Aral Sea, also called Small Aral. Due to the natural (climatic) and anthropogenic reasons in the early XXI century, the Syr Darya river flow grew, its hydraulic regime changed, the spring and summer floods decreased, and the winter spillways increased. These changes affect the dynamics of the floodplain ecosystems and landscapes. In this article we tried to make a complex evaluation of the current trends in those dynamics in the changing environment. The research was made on the basis of the field materials and data of the remote sensing by the Sentinel 2 satellite, as well as climatic and hydraulic data. The analysis of laboratory and field materials was carried out according to the method of evaluation of ecosystems and landscapes transformations under the natural and hydraulic disturbance; the method was created by Zh.V. Kuzmina and S.E. Treshkin. We found out that the main trends for the second floodplain level was hydromorphic forming of salt marshes; for the in-between river bed depressions of river delta it was the gradual decrease of ground water level, while the soil salinity was gradually increasing in the depths and was insignificant on the ground surface; for the third floodplain level and terrace above the floodplain it was the end of the floodplain regime for the researched territory, without increasing salinity of soils; for the depressions of the first and second levels it was the replacement of the perennial and typical grass canopy with annual weeds of some species, due to the death of grass during winter frost and dampness caused by winter spillways.

Keywords: Syr Darya, spring and summer floods, winter spillways, floodplain, ground water level, floodplain ecosystems and landscapes, halophyte vegetation, soil salinity.

DOI: 10.24411/1993-3916-2019-10070