Original scientific paper
Changes in flow and the discharge regime on the Ilova river
Danijel Orešić
orcid.org/0000-0002-5809-085X
; Department of Geography, Faculty of Science, University of Zagreb
Ivan Čanjevac
orcid.org/0000-0002-1536-4128
; Department of Geography, Faculty of Science, University of Zagreb
Mladen Plantak
; Elektroprojekt, d.d., Department for the protection of water, nature and the environment
Abstract
This paper presents the discharge regimes on the Ilova River and their changes since the mid-20th century. Characteristic discharges at the hydrological stations Veliko Vukovje, Munije and Bastaji were analysed. Observation of mean seasonal discharges at the Veliko Vukovje hydrological station showed that in the contemporary period (1991-2016), there was a significant increase of mean autumn discharge and a significant decrease of mean summer discharge compared to the previous climatic standard period (1961-1990). Comparison with seasonal precipitation changes and seasonal air temperatures changes at the Daruvar main meteorological station, situated in the catchment area, proved that they are linked to the seasonal discharge changes on the Ilova River. Comparing the annual courses of mean monthly discharges and monthly modular coefficients in selected periods at Veliko Vukovje, it can be concluded that at the monthly level, the most significant are (summer) decrease of discharges in July and August, discharge decrease in February and a notable September discharge increase. The main differences at the Munije and Bastaji hydrological stations compared to the Veliko Vukovje station is the absence of both absolute and relative decreases of discharge values in the summer months. The main conclusion is that the discharge regime changes observed on the Ilova River are mainly caused by local climate change, despite notable anthropogenic influences in the catchment area, mainly hydrotechnical measures and the presence of relatively large fishponds.
Keywords
discharge regime; discharge trends; Ilova River; hydrogeography; hydrology
Hrčak ID:
216383
URI
Publication date:
29.1.2019.
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