Hydrogeological investigation of karst system properties by common use of diverse methods: a case study of Lička Jesenica springs in Dinaric karst of Croatia

Abstract

Abstract:Lička Jesenica is a sinking river situated in the Dinaric karst environment of the Lika region of Croatia. The two main karst springs, Veliko Vrelo and Malo Vrelo, provide the majority of Lička Jesenica's water. Because of the quality and abundance of the water they contain, these springs are strategically important to the public water supply. Previous knowledge regarding the springs`karst system has been negligible. Therefore, a bulk hydrogeological research program was conducted with the purposes of establishing protection zones and assessing the springs' water-supply potential. The research work comprised the following methods: hydrogeological mapping, setting up of monitoring stations for evaluating discharge and water quality, time series analyses (hydrograph-chemograph), hydrochemical analyses, and geophysical surveys. The main results and conclusions of the research include the following: (i) confirmation that both springs drain a common aquifer; (ii) determination of the highly vulnerable nature of the karst systems; (iii) identification of the Veliko Vrelo Spring's more direct connection to the aquiferdrainage system in comparison to the Malo Vrelo; (iv) estimation of the positions and depths of the springs`main feeding conduits; (v) confirmation of the extent of the geologically presumed catchment area; and (vi) finally, establishment of sanitary protection zones.

Conceptual rainfall-runoff model with a two-parameter, infinite characteristic time transfer function

“…Many reasons can be given for this. The memory effects induced by the infinite characteristic time imply that the model response does not obey an equation of state (it is not only a function of the internal state variables), thus allowing complex processes such as flowpath connectivity/recharge area variations to be better represented. The practical implementation in the form of parallel sub‐reservoirs clearly illustrates the multiple time scale basis of this model, a feature that has been identified as highly desirable in both karst and mountainous catchment modelling (Graeff et al , ; Terzić et al , ). The sub‐reservoir upper volume threshold should not be considered only as a numerical artefact and may bear a physical meaning. This threshold, combined with the small discharge constant of the slower sub‐reservoirs, may also be useful in modelling the occasional activation of high‐altitude springs in mountainous/karst catchments (Petrella et al , ). …”

“…The consequence is a variable response time to the recharge signal (Delbart et al, 2014). Accounting for multiple transfer time scales simultaneously thus appears as a highly desirable feature for rainfall-runoff models (Terzić et al, 2012).…”

Characterization of Aquifers in Metamorphic Rocks by Combined Use of Electrical Resistivity Tomography and Monitoring of Spring Hydrodynamics

“…Spring discharge monitoring, i.e., spring hydrograph, is a basic parameter in determining the dynamic characteristics of an aquifer, which drains at the spring [41]. Monitoring of additional water physicochemical properties (e.g., water temperature and electrical conductivity) can greatly enhance insight into groundwater flow processes [42,43]. High temporal resolution of measurements contributes to a more detailed and reliable characterization of dynamics.…”

An Intermittent Karst River: The Case of the Čikola River (Dinaric Karst, Croatia)

“…Some cases from Dinaric karst are described in the literature [11,[15][16][17][18][19][20][21][22][23]. IRES are common to all Mediterranean karst areas, whereas the soil is quite thin and the infiltration is relatively high [15][16][17][18][19][20][21][22][23]. For Doglioni et al [19], IRES are morphological elements of karstic low-relief areas, characterized by relatively large and flat transects.…”