MAIN RESEARCH ACTIVITIES

Current research activities encompass a field research of flow processes in unsaturated (vadose) zone of an unconfined heterogeneous Zagreb alluvial aquifer (Velika Gorica site) and time series analysis of spring Rakovac flowrate monitored hourly using rectangular sharp-crested weir, Mt. Žumberačka gora (https://www.youtube.com/watch?v=8T99jAE85Xg).

Research polygon at Velika Gorica site

Spring Rakovac, Mt. Žumberačka gora

From year 2003 on, I am developing new methods, solutions and software for Master Recession Curve (MRC) Analysis and Geochemical Background Analysis as well as new methods, solutions and software for hydrogeological data processing.

From year 2012 to 2018, I have been modeling the impact of weirs and hydropowerplant pools (project "Zagreb na Savi") on groundwater levels of the unconfined heterogeneous alluvial aquifers using finite element method (seepage from hydropowerplant pool’s into the drainage systems and hinterland) and finite difference method (regional groundwater flow and contaminant transport modeling).

During the year 2010 and 2011 I have designed and conducted artificial tracer experiment in unconfined heterogeneous alluvial aquifer with highly transient flow conditions within the project GENESIS - Groundwater and dependent Ecosystems: NEw Scientific basIS on climate change and land-use impacts for the update of the EU Groundwater Directive (FP7-ENV-2008-1). Additional geophysical research have been conducted in year 2012.

From year 2009 to 2011, I have developed an objective-based method and a software for analyzing groundwater quality data primarily applicable to large databases. The method and the software mimics subjective appraisal of the graphical presentation of groundwater quality changes in time using five objective-based criterion and extends the analysis in space, in order to assess objective chemical state of groundwater.

Kristijan Posavec