Features of the long-term transformation of the Krasnodar reservoir, near the mouth of the Kuban River, Russia

Abstract

The article considers the long-term transformation of the Krasnodar valley reservoir, the largest in the North Caucasus. The main functions of the Krasnodar reservoir are irrigation of rice systems and flood protection of land in the Krasnodar reservoir region and the Republic of Adygea. According to topographic maps, Landsat satellite images and field observations (2016)(2017)(2018), four stages of transformation of the floodplain reservoir are identified. The selected stages are characterized by both natural causes (the transformation of the filling deltas into the extended deltas, etc.) and man-made causes (runoff diversions in the delta areas, etc.). The key factor of transformation is the formation of deltas of rivers flowing into the reservoir. Each of the selected stages, against the background of a gradual reduction in the area and volume of the reservoir, is characterized by the peculiarities of the formation of river deltas with the formation of genetically homogeneous sections of delta regions. During the period of operation of the reservoir, the delta of the main Kuban River moved up to 32.4 km and took away an area of 35.4 km 2 of the reservoir. During the formation of the deltas of the Kuban and Belaya rivers, a bridge was formed on the Krasnodar reservoir. The evolution of the delta regions led to the division of the reservoir into two autonomous reservoirs. The total area of the delta regions was 85.9 km 2 by 2018, i.e., 21% of the initial area of the reservoir. The transformation of the Krasnodar reservoir leads to a decrease in its regulated volume and gradual degradation.

Analysis of the Bottom Topography of the Reservoir Due to Sediment Trapping (According to the Krasnodar Reservoir, Russia)

“…Sediment trapping is accompanied by a continuous restructuring of the underwater topography due to interrelated geomorphological and hydrological processes -sediment deposition, changes in the local structure of currents, etc. (Litovka et al, 2019;Pogorelov, Laguta, 2020;Pogorelov et al, 2021. Note that the above processes are typical for a number of similar hydraulic structures (Zhang Wei et al, 2015;Andjelkovic et al, 2017;Honek et al, 2020;Shiferaw, Abebe, 2021;Li Xin et al, 2023).…”

“…In the formation of the topography of the reservoir bed and its transformation, the leading role belongs to fluvial processes, of which delta formation processes are the most active. During the period of the reservoir's existence, the evolution of Kuban and Belaya river deltas significantly affected its morphometric characteristics (Laguta, Pogorelov, 2019;Pogorelov et al, 2021). Immediately after the filling of the Krasnodar Reservoir, the alienation of its north-eastern part -the former Tshchik Reservoir -started (Kurbatova, 2014), which was facilitated by the development of the delta of Belaya River, the preservation of the old dam and the collapse of the Tshchik Reservoir.…”

Index-Based Spatiotemporal Assesment Of Water Quality In Tarbela Reservoir, Pakistan (1990−2020)

“…Reservoir construction, as an anthropogenic activity continue to alter and influence fluvial processes, including sediment transportation, its resultant altered river geomorphology, geochemical composition of water and ecology (Pogorelov et al 2021, Condé et al 2019. The uncontrolled population increase, along with climatic variability, leads to intensive land use practices that impact the water level and clarity of water in inland water reservoirs.…”