Desalination and filling of river waters on the Don basin sandy lands: Geoecological component

The research purpose is to assess the mesorelief geoecological significance in the desalination and filling of the river waters of the Kazanskaya-Veshenskaya sand massif. The studies were carried out on the watercourses of the eastern (Kumylga, Khopyor, Srednaya Elan’, Sukhaya Elan’, Malaya Peskovatka, Peskovatka rivers and spring in the Shakinskaya oak grove) and western (Otrog spring and situated in Kazanskaya forestry spring; Peskovatka, Elan rivers) parts of the massif. It is established that the underground runoff is 70% of the amount runoff through open watercourses (or 89 thousands m 3 ). In October, the total daily flow through the Kazanskaya-Veshenskaya sand massif is 216 thousand m 3 . The annual groundwater supply is equal to 141.6 million m 3 . A third of this water is discharged in two spring months. The remaining 99.1 million m 3 are discharged into the groundwater during the remaining 10 months. On average, this amounts to 330 thousand m 3 per day.