Long-term temperature fulctuations in rivers of the Fore-Sudetic region in Poland

Abstract

The paper presents an analysis of water temperature fluctuations in four rivers: Nysa Łużycka, Bóbr, Bystrzyca, and Nysa Kłodzka, in south-west Poland (Fore-Sudetic region) in the period 1971-2014. The obtained results show an evident increase in water temperature ranging from 0.15 °C·dec⁻¹ to 0.33 °C·dec⁻¹. Such changes were particularly determined by changes in air temperature. Water temperature increased in two analyzed stations: Zielona Góra and Wrocław by 0.37 and 0.35 °C·dec⁻¹, respectively. While the variability of the rate of warming of particular rivers in the analyzed region should be associated with local factors occurring in the catchments, the contribution of forest cover is of key importance. A change in water temperature constituting its primary parameter will cause further transformation of the discussed river ecosystems. Combined with poor water quality, rising water temperatures can become a factor inhibiting further economic development of the Fore-Sudetic region in Poland.