In hydrology the term »low-flows« indicates a flow which is followed after longer periods of dry weather. As such low flows are an essential part of any stream flow regime and their understanding is an important part of effective water management. In this graduate thesis we presented an overview of main low-flow indices, such as low-flow statistics, base flow index, recession curve and stream flow deficit analysis, flow duration curve and seasonality indices such as seasonality index and ratio. The calculations of analysed indices were carried out in a software environment R inside a package for low-flow analysis lfstat. The indices were calculated on a case study of the Kokra I gauging station in order to explain the low-flow regime of the Kokra river. Appropriate initial parameters were set when analysing stream flow deficit and the recession curve. Flow duration curves were drawn on a yearly basis as well as separately for different seasons. In seasonality analysis the winter regime of lowflows was found to be the case for the Kokra river based on seasonality ratio and index values. Furthermore the analysis of low flows was expanded on another 55 gauging stations across Slovenia with each one of them being assigned the stream flow regime. Stream flows were compared based on calculated statistics, such as QMF, Q70, Q90, Q95, MAM1 and MAM7, base flow index, seasonality index and ratio and different indices of recession analysis and stream flow deficit analysis. The correlation of the calculated indices was analysed and graphical presentations of seasonality indices were made.
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