Peculiarities of water runoff and pollution in Lielupe watershed

Abstract

The quality of water in rivers depends on physical – geographical conditions of a watershed; it is also affected by economical activities of people. The article analyses the variation of runoff and biogenic materials in the Lielupe river watershed area (RWA) – the Levuo, Tatula and Nemunėlis rivers within 1992–1996 and 1997–2004 periods, during which the intensity of the economical activities of people was varied.. The state monitoring data was used for the investigations. The data collected in the Lithuanian Hydrometeorological Service was used to describe the river runoff variation and the data from the Environmental Protection Agency was used to analyse the river water quality. The statistical parameters of the main runoff characteristics were calculated to analyse runoff variations. The variation of biogenic material concentrations was analysed to evaluate the water pollution.