Application of environmental tracers to study the drainage system of the unsaturated zone of the Ljubljansko polje aquifer
AbstractThe groundwater recharge processes were investigated in the unsaturated zone of the Ljubljansko polje intergranular aquifer. The study based on application of environmental tracers. The monitoring of the drainage system was established at an urban lysimeter consisting of artificial and autochthonous sediment layers. Groundwater was sampled with the suction cups instaled at depths of 0.3, 0.6, 1.2, 1.8, 3.0 and 4.0 m. The results pointed out the most important factors that control the hydrodynamic processes and solute transport in the study site where the soil cover and Vegetation are missing. The physico-chemical and isotopic properties of sampled groundwater indicated that the clayey layers have an important role in the hydraulic behaviour of the unsaturated zone. As a consequence of a piston effect the event and pre-event water concentrate above these layers causing lateral flow. A vertical breakthrough of this water into lower layers of the unsaturated zone could occur through preferential paths during intensive precipitation events in dependence on pre-accumulated water volumes. Under such conditions groundwater residence time is about 2 months in the unsaturated zone 3 m below the surface.
How to Cite
Trček, B. (2017). Application of environmental tracers to study the drainage system of the unsaturated zone of the Ljubljansko polje aquifer. Geologija, 60(2), 267–277. https://doi.org/10.5474/geologija.2017.019