Modelling of water regime in karst

Abstract

Underground flow regime in karst areas completely differs from flow in intergranular aquifers. Hydraulically, this flow can be better described as a system of reservoirs and pipes with flow under pressure and with free surface, than as underground flow in intergranular aquifer. A simplified (conceptual) physically based model of water regimes in karst areas is presented in the article. Vertical water movement and leakage from unsaturated zone is simulated using UNSAT model. The model for water balance in horizontal plane is based on quasi-steady hydraulic simulation, with the case study for the catchment area of Bregava river spring zone in Eastern Herzegovina.

Zakonitosti tečenja podzemnih tokova u karstnim predelima u potpunosti se razlikuje od tečenja u intergranularnoj sredini. U hidrauličkom smislu, ovo se tečenje bolje se opisuje zakonitostima tečenja u kanalima (cevima) pod pritiskom i sa slobodnom površinom, nego klasičnim tečenjem kroz poroznu sredinu. U ovom radu prikazan je jedan konceptualni (pojednostavljeni) fizički model, u okviru koga je vertikalni vodni bilans modeliran UNSAT modelom, koji se zasniva na tečenju kroz nezasićenu sredinu, a tečenje u horizontalnom pravcu modelirano je kvazi ustaljenim strujanjem. Model je urađen za slivno područje izvorišne zone reke Bregave u Istočnoj Hercegovini.