Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling

This paper deals with karst aquifer characterization using time series and stochastic analysis and modelling as well as groundwater quality analyses. Such a methodological approach was applied on the eastern Suva Planina Mt. karst aquifer by evaluating data for the period of 2015-2018, which included monitoring and analysis of major karst springs Mokra and Divljana and their quantity and quality parameters. Quantitative characterization of these karst springs utilised for water supply of Nis city, has shown high karstification degree and very well retention capacity of both, Mokra and Divljana sub-systems with slightly lower storativity of the Divljana sub-system. In addition, simulation models have proved that precipitation is the main driving force of the hydraulic behaviour of the karst groundwater circulation and discharge in this area. Qualitative characterization has shown very small variation of chemical parameters, with expected karst groundwater fingerprint, and isotopic analysis confirmed that water replenishment is relatively fast. Results also speculate that these two springs actually represent discharging points of one aquifer that is fragmented into two interconnected sub-systems. The study proves the necessity for karst groundwater characterization to manage this important natural resource in a sustainable way.