Die Bodenkultur - Journal for Land Management, Food and Environment

E. Tomaszewski:

Multi-annual variability and homogeneity of drought streamflow deficit


The aim of this contribution has been to analyze multi-annual variability of drought streamflow deficit as well as to indicate some its determinants. The determination of low flow periods and estimation of the streamflow deficit were based on the threshold level method, where the seventieth percentile from the flow duration curve was used as the criterion. Basic calculations were made for daily discharge series at 22 gauging stations situated in the basins of the Warta, Pilica and Bzura River over the time period 1951–2000. Analysis involved multi-annual tendency and homogeneity of streamflow deficit determinatives, homogeneity interruptions and autocorrelation. Also investigated was the question of a relationship between factors which are crucial for hydrological drought development. Key words: Hydrological drought, low flows, multi-annual runoff variability and homogeneity.