Chemical composition of surface water in the main tributaries of Lake Baikal – the Selenga and the Barguzin Rivers

Abstract Lake Baikal is one of the oldest fresh water bodies on the planet, where the largest available water reserves are concentrated. River runoff plays an important role in the overall balance of substances entering the Lake. The Selenga River is the main tributary of Lake Baikal, in the basin of which, unlike other tributaries, a large number of industrial, agricultural, processing enterprises, settlements and cities are concentrated. The Barguzin River is the third largest river flowing into Lake Baikal, is the basin where intensive development in agriculture and forestry has undertaken. This paper presents the results of the analysis of surface water samples of the Selenga and Barguzin rivers collected during 2015-2016. In 2015, the water level for the Selenga and Barguzin rivers was characterized by extremely low water content, which caused an increase in the concentrations of major ions and trace elements in surface waters. The more favorable water regime in 2016 caused a significant decrease in ion concentrations. Maximum concentrations of iron and manganese are observed in winter and during flooding in the spring. In conditions of low water content, increased copper and zinc contents were also observed in the surface water of the Lake tributaries.</jats:p

The content of heavy metals in the water of Lake Gusinoe (Western Transbaikalia) and its tributaries

Abstract Investigation of the transformation of substances in the basin of the Selenga River, the main tributary of Lake Baikal, due to anthropogenic impact under conditions of global climate change, is especially important for Lake Baikal which is a World Natural Heritage Site and the main source of fresh drinking water not only in the region, but also in the world. One of the key research objects in the Selenga River basin, which is subject to significant anthropogenic impact, is the ecosystem of Lake Gusinoe. This study presents the results of analysis of the physical and chemical parameters of the water mass of Gusinoe Lake basin. for the period from 2017 to 2020. Thus, the results on hydrochemical indicators for a long-term period of research of the lake show changes in the chemical composition of water and the concentration of main ions. In 2020, the content of almost all metals was higher than in 2017-2020, which may be due to the rise in the level of Lake Gusinoe and groundwater that began in 2019 and continued in 2020, as a result of rain floods that caused flooding of the coastal territories and the entry of pollutants into watercourses and the lake.</jats:p

THE CHINESE INITIATIVE “THE BELT AND ROAD”: A GEOGRAPHICAL PERSPECTIVE

“The Belt and Road” is a long-term comprehensive strategic program for the development of Eurasia and the world, which has been promoted by China beginning in 2013. Its multi-dimensional features (in-country, regional, and global) are inclusive (multi-vector, the participation of all sectors of the economy) and have a strong non-economic component (“soft power”). The strategy is aimed at solving the problems of the Chinese economy with the help of foreign-policy methods and consolidation of China as an engine for the global economy. By virtue of its scale, the consistent implementation of the strategic provisions put forward in China would result in significant industrial and geographical transformations of the existing international division of labor. Active and proactive participation of Russia in the new course of China allows realization of the export and transit potential of Russia’s economy and helps mitigate imbalances in development between its parts. The authors discuss the concerns and risks associated with the implementation of initiatives

Heavy Metal Content in Fish of the Barguzin River (Eastern Cisbaikalia) and Assessment of Potential Risks to Human Health

In this paper, the levels of nine heavy metals in the organs and tissues of six commercially important fish species from the Barguzin River (Eastern Cisbaikalia, Russia), bream Abramis brama, roach Rutilus rutilus, crucian carp Carassius carassius, common carp Cyprinus carpio, perch Perca fluviatilis and northern pike Esox lucius, were investigated. The distribution of HMs in the fish organs and tissues was unequal and was determined by both their physiological functions and routes of entry. The study also characterized the environmental habitats, including water and sediments, and conducted an assessment of potential risks to human health associated with fish consumption. The results showed that the levels of Fe, Zn, Cu, Ni, Cd, Pb, Cr and Hg in the muscle tissue of fish from the Barguzin River were generally low and did not exceed the maximum allowable concentrations established in Russia and worldwide. However, Mn levels in a number of samples exceeded the corresponding maximum allowable concentrations, which may be attributed to its elevated presence in the habitat. The calculated fish condition factor K showed good health status of fish from the Barguzin River. The highest Metal Pollution Index values were recorded for northern pike scales (5.9), which, however, corresponded to a low level of contamination. The other metal pollution index values for fish organs and tissues were all below five, indicating either no or very low contamination. Risk to human health was assessed using target hazard quotients and hazard index. None of these indices, both for each fish species studied and for each of the nine heavy metals, exceeded one. This indicated that consumption of the fish species studied did not pose an excessive risk of non-carcinogenic health effects to humans. The data on the content of nine heavy metals in the main commercially caught fish species from the Barguzin River indicated a low level of tissue and organ contamination by heavy metals and the absence of health risks to humans associated with their consumption as food

Distribution of Heavy Metals in Water and Bottom Sediments in the Basin of Lake Gusinoe (Russia): Ecological Risk Assessment

Fresh water scarcity is considered a significant component, and potentially one of the most critical, of global climate change. With the rapid development of industry, there is an increasing risk of freshwater contamination by heavy metals (HMs). The danger of HM pollution is also attributed to their accumulation, which can subsequently become a source of secondary pollution in aquatic environments. In the Lake Gusinoe basin, located in Russia, concentrations of HMs were measured in both water and bottom sediments within the lake area, as well as in inflowing and outflowing watercourses. Ecological risk indices were also calculated for the Gusinoe basin. Our results showed that the average concentrations of Fe, Zn, Cr, Ni, Cd, and Pb in the water did not exceed the maximum allowable concentrations (MACs) set by Russian national standards and WHO standards, while the concentrations of Mn and Cu exceeded the corresponding MACs during winter, spring, and autumn possibly due to decomposition of aquatic vegetation and influx from groundwater sources. The average concentrations of the investigated HMs in the BSs did not exceed the background values. The water hazard index indicated a low risk for all samples in the lake water area. For all BS samples, the geoaccumulation index (Igeo) and the Pollution Load Index (PLI) indicated low pollution levels, while the values of the Enrichment Factor (EF) and the Contamination Factor (CF) indicated moderate pollution in the central part of the lake. The Ecological Risk Factor (Er) for Cu in BSs at points near major settlements and in the Tel River indicated moderate pollution. The Potential Ecological Risk Index (RI) in all investigated BS samples indicated a low risk of contamination