INFLUENCE OF THE BIOGEOCHEMICAL SITUATION OF THE LAKE TELETSKOE CATCHMENT (NORTH-EASTERN ALTAI) ON THE CONTENT OF THE MAJOR IONS AND Fe IN THE TRIBUTARIES WATERS

Abstract

The relevance of the research is caused by the necessity to expand and deepen knowledge about the formation and functioning of large freshwater objects, the chemical composition of which is closely related to the peculiarities of biogeochemical processes and soil cover of the catchment, with type of the anthropogenic environmental impact of catchment basins. However, the mechanisms of these interactions in the mountainous territories have not been fully studied yet. The main aim of the research is to establish the relationship between the content of the major components in the tributaries waters of Lake Teletskoe and the features of their chemical denudation with the biogeochemical situation on the catchments. Methods. Water samples from the tributaries of Lake Teletskoe were collected in clean polyethylene dishes in the estuary of the rivers, during the spring-summer high water and autumn low water. Determination of the ionic composition of surface waters (HCO3–, Cl–, SO42–, Ca2+, Mg2+ Na+ and K+) was carried out according to standard methods, with titrimetric or spectrophotometric completion. Na+ and K+ in 2018 and 2019 were determined by atomic emission spectrometry on the IRIS Advantage Thermo Jarrell Ash Corp. instrument. (1999). Fe content in waters and water extracts from soils was determined by atomic absorption spectrometry using electrothermal atomization on the SOLAAR M-6 device. Results. It is established that the waters of the Lake Teletskoe tributaries are characterized by a low total mineralization (TDS), from 18 to 159 mg/L. It is shown that the seasonal dynamics of the major ions is determined by the biogeochemical processes in the catchment. It is revealed that the waters of the eastern and western tributaries, draining different geological and landscape structures, as well as the degree of recreational load of the coast, differ both in content and in the ratio of the major ions. Thus, Cl– and SO42–, K+ and Na+ make a greater contribution to the ionic composition of the waters of the eastern tributaries originating on the Korbu granite ridge, whereas in the waters of the western tributaries, draining sedimentary deposits for the most part, bicarbonates and calcium dominate. The influence of biogeochemical conditions of catchment on the content and ratio of iron in water and water extraction of soils is shown. It is revealed that most of the tributaries carry bicarbonate-magnesium-calcium type waters. The indicators of ion runoff of three tributaries of the lake of different sizes are calculated, chemical denudation in their catchment basins is estimated. In one year, 364 thousand tons of soluble salts enter the lake with the waters of the largest tributary – the Chulyshman River. 21 tons of salts are removed from 1 km2 of the Chulyshman River catchment (this is less than from the catchments of smaller tributaries), of which 12,8 tons are hydrocarbonates, 1,4 tons are chlorides, 1,6 tons are sulfates, 4,5 tons are calcium, 0,4 tons are magnesium.

Keywords

• lake teletskoe
• tributaries
• catchment area
• major ions
• iron
• biogeochemical situation
• ion runoff