Assessment of the relationships between elements and organic matter in water after a large landslide in the Bureyskoye reservoir (Russia)

¹ Computer Center of the Far Eastern Branch of the Russian Academy of Sciences, Kim Yu Chena street, 65, 680000, Khabarovsk, Russia
² Institute of Water and Ecology Problems of the Far Eastern Branch of the Russian Academy of Sciences, 56 Dikopoltsev St., Khabarovsk, Russia.
³ Kosygin Institute of the Tectonics and Geophysics of the Far Eastern Branch of the Russian Academy of Sciences, 65 Kim-Yu-Chen St., Khabarovsk, Russia

^* Corresponding author: ktvsl@mail.ru

Abstract

The article provides information on statistical approaches to identify the dominant factors that influenced the water quality in the Bureyskoye reservoir after a large landslide in December 2018 blocked access to a hydroelectric power plant. To restore the hydrological regime, blasting operations were carried out using trinitrotoluene and hexogen. The main indicators of water quality were volatile organic matters and elemental composition that varied along different banks above and below the landslide body and under the influence of explosives. In water samples from the artificial canal after the restoration of the reservoir flow, the content of Fe, Mn, Al, Cu and Zn remained at a low level and did not reach the initial values established prior to the blasting operations. However, an increase in the content of Pb by 7 times and Hg by 80 times was noted. The presence of methanol and methylated benzene derivatives in water could stimulate the formation of more toxic methylmercury, posing a risk to aquatic organisms. Correlation analysis was used to process the obtained data which made it possible to differentiate the contributions of natural (landslide, river tsunami) and anthropogenic factors (blasting) to the change in the chemical composition of water in the reservoir.