The water bodies of Azerbaijan were formed over a long geological timeframe and changed significantly throughout that period. This is particularly evidenced by remnants of ancient rivers found throughout the country. The country's water systems are continually changing under the influence of natural forces and human introduced industrial activities. Artificial rivers (canals) and ponds are a part of Azerbaijan's water systems.
According to the 1999 population census, the ethnic composition of the population is: 90.6% Azeris, 2.2% Lezgins, 1.8% Russians, 1.5% Armenians (almost all live in the break-away region of Nagorno-Karabakh), 1.0% Talysh (disputed as too low by Talysh nationalists), 0.6% Avars, 0.5% Turks, 0.4% Tatars, 0.4% Ukrainians, 0.2% Tsakhur, 0.2% Georgians, 0.13% Kurds, 0.13% Tats, 0.1% Jews, 0.05% Udins, other 0.2%. Many Russians left Azerbaijan during the 1990s.