Update for the biodiversity and inflows of Araz River (Azerbaijan)

The article provides updated information about the hydrological characteristics, biodiversity and the influence of these and other anthropogenic factors in the Araz River and some of its tributaries in Azerbaijan.Its is revealed that concentration of such unnatural components as heavy metals, phenols, oil products and other pollutants in the water of the river highly increased during last 50-60 years. As a result, the proportion of dissolved oxygen in the water is partly decreased, while the degree of water mineralization increased 2-4 time. Ten species of macrophytes, 34 species of fishes, 28 species of zooplankton organisms belonging to 3 ecological groups and 95 species of macrobenthic organisms, belonging to 14 systematical groups, were found in Araz River. 6 groups (60 species) of macrobenthic organisms were revealed in the faunas of Okhchuchay River and Hakarichay River.