Impact of urbanized landscapes on the river flow in Europe

Abstract

Global urban landscapes were growing rapidly during last decades. The impact of this growth on annual river runoff of foreign European and Russian river basins was shown in this article. Calculations for Moscow river basin were taken as a basis for computations. The performed calculations show, that 1% of urbanization area increase also enhances total river runoff at 1%. At the same time 1% growth of watertight territories (included in urbanized landscapes) leads to an increase in runoff by 2–3%. The growth of urbanized areas led to a smaller increase in runoff (2–3 times) in the past (in comparison with current period) due to a less established system of diversion from urbanized landscapes. Calculations were made for Spree, Thames, Seine river basins in comparison Moscow River basin. Impact of capitals landscapes (Berlin, London, Paris, and Moscow) on river runoff was estimated initially, and then the influence of other urbanized areas located in river basins. As a result, the general influence of all urbanized territories was defined. According to results of conducted calculations, modern urbanized areas led to an increase of annual river runoff by more than 9% in Spree river basin, more than 20% of the Thames, over 11% of the Seine and 10% in the basin of Moscow River in comparison with changes during the period of norm calculation (from the end of 19th century till the beginning of the 1960s of the 20th century). According to the results of conducted calculations, modern total annual runoff increase is 2.2–4.5% for Europe and 0.2–0.3% for the Russian Federation in comparison with changes during the period of norm calculation, and in relation to the runoff from the most populated their parts is 3.5-6.9% and 1-2%, respectively. In addition, it can be expressed in km3 with following values: 44.9–89.8 (for foreign Europe) and 7.2–14.3 (for the Russian Federation). For the whole Europe (including European territory of Russia), the runoff increases by 50–100 km3 (or by 2–4%) per year. Actually, this is not so much in percentage terms, though in terms of volume – these values are close to annual runoff of such river as Neva.