Ecological status water bodies of the urban environment on the example of the city of Tyumen

The article uses various research methods to study the ecological state of two water bodies (Olovyannikov Pond and Tsimlyanskoye Lake) in the Kalininsky District of Tyumen. The analysis was conducted based on the main physical, chemical, and organoleptic properties of the water. According to the results of laboratory studies of the water samples from the water bodies, the water has an earthy odor at 20°C and 60°C, which corresponds to the maximum permissible concentrations. The color of these objects varies from 36 to 51 degrees of color, and the turbidity ranges from 33.4 to 61.6 units of turbidity according to formazin per 1 liter. According to the hydrogen index, the water in the studied objects is characterized as slightly alkaline, ranging from 7.3 (Olovyannikov Pond) to 7.5 (Tsimlyanskoye Lake). Chemical studies have shown that the surface water samples of Lake Tsimlyanskoye exceed the maximum permissible concentrations of the following substances: chemical oxygen consumption is 7.6 times higher, biochemical oxygen consumption during the analysis on the 5th day – 17.5 times. In the water samples of the Olovyannikov pond, the excess was noted for chemical oxygen consumption in 4.1 times, biochemical oxygen consumption during the analysis on the 5th day – 13 times, chlorides – 1.5 times, phosphate ions – 4.5 times. Exceeding the maximum permissible concentrations for sulfate ions and dissolved oxygen was not noted. According to the results of biotesting, the highest germination rate was observed in the control variant (92%), which is 4% and 12% higher than in the 2nd and 3rd variants, respectively. The state of water bodies in the Kalininsky District of Tyumen is assessed as very dirty, which is confirmed by the calculation of the water pollution index (the water pollution index of Lake Tsimlyanskoye is 7.6, and the water pollution index of Olovyannikov Pond is 7.2) and the results of biotesting.