Original scientific paper
https://doi.org/10.21861/HGG.2012.74.01.04
Changes in Discharge Regimes of Rivers in the Croatian Part of the Danube River Basin
Ivan Čanjevac
orcid.org/0000-0002-1536-4128
; University of Zagreb, Faculty of Science, Department of Geography, Zagreb, Croatia
Abstract
This article deals with the changes in discharge regimes of rivers in the Croatian part of the Danube River Basin. In the first part, the overview of the methodology and results of researches of discharge regimes of rivers in Germany, Switzerland, Austria and Slovenia is given. In the second part changes in runoff regimes were analyzed, comparing the standard thirty year time period (1961-1990) and the last thirty year period (1980-2009) for 12 selected hydrological stations on 11 rivers in the Croatian part of the Danube River Basin. To assess the change in regimes, comparison of module (Pardé) coefficients between the two time series was done. In addition, a Kendall-Theil (Sen) non-parametric trend test was carried for the yearly and seasonal values of discharge. The results show changes on all the analyzed rivers and stations. There is evidence of redistribution of discharge throughout the year, increase in autumn and winter discharge (especially on rivers dominantly fed by snowmelt) and decrease in summer values of discharge. In addition, we detected a change in the month of the appearance of discharge maxima and minima. The changes can be described through changes in the regime of climate elements (temperature, precipitation, evapotranspiration). Further analyzes should focus on the catchment scale in order to assess all the relevant factors influencing changes in the discharge regime of each river.
Keywords
discharge regime; discharge trends; Danube River Basin; Croatia; hydrogeography; hydrology
Hrčak ID:
86468
URI
Publication date:
1.9.2012.
Visits: 2.834 *