Changes in the Physical and Chemical Parameters of Water during an Abnormally Hot Period

Increased air temperatures during the 2010 growing season contributed to an increase in water temperatures. This was reflected in changes in the physicochemical characteristics in the water of the Ild River mouth area, a tributary of the Rybinsk reservoir. During the period of maximum water heating in 2010, the total amount of organic matter, its labile fraction, and suspended solids were significantly higher compared to the period close to the long-term average. Organic matter was predominantly freshly formed compounds; the suspended form of iron predominated over the dissolved one. A highly significant correlation was noted between temperature and organic matter parameters. At the same time, temperature anomalies did not affect the content of dissolved oxygen, mineralization, and color of the water.