The relationship between the formation of madflow and the concentration of nitrogen compounds in mountain rivers (on example of Akhangaran river)

Abstract

In the Republic of Uzbekistan, mountainous and foothill areas are areas with a high risk of floods. The rivers with the most dangerous floods include the basins of the Chirchik River (2-3 times a year) and the Akhangaran River (3-6 times a year) in the Tashkent region. In this article, the level of pollution along the length of the Akhangaran River with nitrogen compounds and suspended solids during heavy precipitation, as well as their relationship, were studied. Water samples were taken from a total of 15 hydroposts, in the Akhangaran River - from the upstream of the Akhangaran reservoir to the city of Akhangaran (13 hydroposts) and additional hydroposts in the Syrdarya River and in the tributary of the Kamchiksai. To conduct this research were used methods as: photometric - to determine the concentration of nitrogen compounds, gravitational - to determine the amount of suspended solids, statistical (correlation analysis) - to understand the relationship between the studied parameters and heavy precipitation, in mountainous and foothill areas. It was established that during the period of heavy precipitation in April and May, the amount of nitrite nitrogen (N-NO₂), nitrate nitrogen (N-NO₃) compounds and suspended solids in the river were at a high level, and during the low-water period (August, October), their number decreases. The obtained results of laboratory and statistical analyzes confirmed the existence of a relationship between the formation of flood flows in mountain rivers and an increase in the content of nitrogen compounds (R² = 0.64) and the amount of suspended solids (R² = 0.67).

Key words: цater pollution, nitrogen compounds, suspended solids, correlation, Uzbekistan, Tashkent region.