Since the 1990s Kazan hydrochemists have been observing that unfortunate shallow portions of the Kuibyshev reservoir are self-cleaning. The quality of water here has very much changed: if earlier shallow waters were described as "polluted", now they are "slightly polluted" and even "mostly clean". It is not clear why the ecology of shallow waters is improving. According to specialists, this is due to increasing biological potential of ecosystems' stability.
Kuibyshev is the largest reservoir on the Volga river and the seventh in the world. Formed by the Volzhskaya hydro dam in the middle reaches of the Volga, the reservoir was filled in 1955-1957. Its area is 5,900 square kilometres, volume 56 cubic kilometres, length 510 kilometres, maximal width 27 kilometres.
Jointly with Tatar environmentalists, the Kubyshev reservoir has been under study for three years by scientists from the German Department for System Botany and Ecology.
The international conference Ecology Problems of the Flatland Water Reservoirs' Littoral was held in Kazan on October 11 through 15. Ecologists from Moscow, Perm, Samara, Nizhni Novgorod, Togliatti, Novosibirsk, Yakutia, other cities participated.
