Integrated assessment of the spring waters of the Bryansk region in the system of state monitoring

The results of ecological-chemical and toxicological analysis of 20 model springs on the territory of urban and rural settlements of the Bryansk region within the framework of water monitoring are presented. Indicators of hydrochemistry and phytotoxicity by the biotesting method are presented. The springs are classified according to temperature, flow rate, pH value, salinity and total hardness. Correlation relationships between the obtained hydrochemical indicators of spring waters are shown. The additions to the monitoring base for the state of spring waters in the summer low-water period of 2020 showed that the dominant pollutant of water in the tracts of the urban areas of the Bryansk region is nitrate ions; the total iron content exceeds the permissible norms. Among the model springs, 25 % have an excess of the content of nitrate ions relative to the norms of maximum permissible concentrations (45 mg / L), 20 % - a significant excess of the normalized indicator «total iron» (0,3 mg / L). Calculation of the phytotoxicity index showed that water samples from two springs are toxic (coefficient J > 20). Ecological and chemical analysis of springs and determination of the degree of hemerobity of the spring tract showed that nitrate ions and chloride ions are indicator indicators of anthropogenic impact on natural waters. Conjugate analysis of water hydrochemistry indicators revealed strong correlations between the parameters “total mineralization - total hardness”, “total mineralization - chloride ions”, “electrical conductivity - chloride ions”, “electrical conductivity - total hardness”, “electrical conductivity - total mineralization”. The springs are ranked according to the degree of anthropogenic transformation of the landscape. On the scale of hemerobicity, the spring tracts were classified according to seven degrees: metagemerobic (one spring), polyhemerobic (two springs), α-euhemerobic (two springs), β-euhemerobic (one spring), mesohemerobic (six springs), oligohemerobic (eight springs).