Seasonal resources of groundwater in the area of waterbody of eastern Slavonia in the Drava river basin : master’s thesis

U ovom radu određene su sezonske zalihe podzemne vode na području vodnog tijela istočna Slavonija u slivu Drave te je izračunat udio oborina koji prihranjuje sezonske zalihe podzemne vode promatranog područja u razdoblju od 1.10.2013. godine do 30.9.2014. godine. Korišteni su podaci iz trideset piezometara te podaci o oborinama s dvije meteorološke postaje na istraživanom području. Odabran je datum u kojem većina piezometara ima minimalne razine podzemne vode (niske vode - 3.10.2013.) i datum u kojem većina piezometara ima maksimalne razine podzemne vode (visoke vode - 19.5.2014.) te su izrađene karte ekvipotencijala. Oduzimanjem ekvipotencijala za visoke, odnosno za niske vode, dobivena je karta amplitude piezometarske razine. Sezonske zalihe podzemnih voda izračunate su množenjem površine istraživanog područja sa srednjom vrijednosti amplitude kolebanja piezometarske razine i efektivnom poroznosti pri čemu je dobivena vrijednost od 5,09x108 m3 podzemne vode u promatranom razdoblju. Podaci o oborinama na temelju kojih je određen postotak oborina koji prihranjuje podzemne vode dobiveni su iz meteoroloških postaja Našice i Osijek. Sezonske zalihe podzemnih voda podijeljene su sa ukupnom količinom oborina u promatranom razdoblju te je izračunato da udio oborina koji obnavlja sezonske zalihe podzemne vode istočne Slavonije u slivu Drave iznosi 14,21%.Abstract: In this thesis, seasonal groundwater resources in the area of eastern Slavonia waterbody in the Drava river basin are determined and the proportion of precipitation that recharges seasonal groundwater resources in the observed area in the period from 1th October 2013 to 30th September 2014 is calculated. Two dates were selected, the first one on which the majority of piezometers had the minimum level of the groundwater (low water - 3th October 2013) and second one on which the majority of the piezometers had a maximum level of groundwater (high water - 19th May 2014) and the maps of equipotentials lines were made. The map of the fluctuations in the level of groundwater was obtained by subtracting the equipotential lines of high, and of low water. Seasonal groundwater resources were calculated by multiplying the surface areas of researched area with mean values of amplitude fluctuations in the piezometer level and the effective porosity, whereby the value of 5, 09x108 m3 of groundwater in the observed period was obtained. The precipitation data were obtained from the meteorological stations Našice and Osijek and, based on them, a certain percentage of precipitation which recharges groundwater was determined. Seasonal groundwater resources were divided by the total amount of precipitation in the monitored period and it was calculated that the proportion of rainfall that replenishes the seasonal groundwater supply of Eastern Slavonia in the Drava river basin is 14,21%