Manganese in the hydrosphere of the Jewish autonomous region: surface water

Abstract

At present, knowledge about the content of manganese in the surface waters of the Jewish Autonomous Region is becoming more and more relevant, since the development and extraction of iron-manganese ores has already begun in the area of the Bidzhan deposit in the north-west of the region. It is planned to develop iron-manganese deposits in other regions of the autonomy. However, we are not sufficiently aware of the migration of this element, its spread by watercourses along the hydraulic network, the change in the forms of transportation due to the boggy territory of the autonomy, and the possible negative impact on aquatic organisms. The purpose of our work is to study the distribution of manganese in surface watercourses, taking into account the geological features and natural conditions of the Jewish Autonomous Region. The content of total manganese in the surface waters of the Bira River and mainly its northern tributaries located on the territory of the autonomy was determined by the method of atomic absorption spectrophotometry. The article presents the results of determining manganese and iron, as well as indicators that affect their migration ability, in the surface watercourses of the Jewish Autonomous Region for two years. The paper describes and analyzes the natural conditions and geological features of the autonomy that affect the distribution of manganese in its surface waters. As a result of the study, it was revealed that all rivers reflect the specific nature of the natural conditions of their formation. In the watercourses of the northwestern part of the region, draining the foothills of the Small Khingan, the influence of deposits of ferromanganese ores is clearly manifested. In the rivers flowing from the southern spurs of the Bureinsky ridge, manganese ore content is not felt. Bira's sharp turn from the mountainous north to the south, to the Amur, occurs against the background of a contrasting change in the relief and close contact of the river with the adjacent swampy plain. Natural processes and sources of Mn input into river waters change: the input of soluble humid metal complexes from the bog drainage begins.