Ecological state of the small Plyushchikha river within the boundaries of the city of Novosibirsk

Abstract

The Plushykha River is one of the nine small urban rivers of Novosibirsk feeding the Ob. In its coastal zone there are garden societies, highways, railways, which have a significant impact on its condition. The purpose of this work was to assess the state of the coastal zone and some hydrochemical and physical indicators of the water of the Plyushchikha River within the city of Novosibirsk. According to the results of the observations, erosion of coastal slopes by thawed and stormwater was noted, siltation of the Ivy riverbed is observed in the summer. When studying the physical parameters of water, an increase in the intensity of odor in the spring, summer and winter period was noted to 3.0; 4.8 and 2.8 points, respectively. The color index in winter and spring is 44°, which is 2 times higher than the MPC, in summer — 54°, which is 2.7 times higher than the MPC. There was also an excess of the permissible turbidity value in the spring period by 2.6 times, and in the summer and winter periods by 3.6 times. The pH of the water in summer and winter is slightly alkaline, and in spring it is alkaline (9.0 units), the hardness of the water of the Plushykha River varies depending on the season. In spring, this indicator was 4.62°F, in summer — 5.32°F, and in winter — 10.56°F, which is slightly higher than the MPC (10.0°F). The total alkalinity of the water was 9.5 mg*eq/l in spring, 7.5 mg*eq/l in summer, and 12.54 mg*eq/l in winter, with a norm of up to 7.9 mg*eq/l. The concentration of nitrates in the spring and summer periods exceeded the maximum permissible value for natural reservoirs (0.2–1 mg/l) and amounted to 10.0 and 12.3 mg/l, respectively. The level of nitrite ions in river water in spring and summer was 0.7; 0.4 mg/l at MPC — 0.2 mg/l.