Hysteresis in semi-confined fractured rock groundwater- discharge relations related to runoff formation on a small basin scale

In hydrology hysteresis is a common phenomenon the apperception of which strongly depends on filling stage of hydrological storages and intensities of the related input and output processes. To discover hysteretic relations between variables, high resolution in time and small-scale are favourable, mainly when intercalated complex fractured rock aquifer systems control water transfer towards discharge at basin outlet. Accordingly, for example piezometric table/ hydraulic head-discharge connections might be hysteretic as a result of non-linear system reactions, as shown in Fig. 1. Unfortunately the valuable anthology of streamflow generation processes edited by BEVEN (2006) does not mention hysteretic behaviour as important hydraulic feature. Early protagonists for hysteresis in hydrology were MUALEM (1974, 1984) devising theoretical considerations, and DRACOS & STAUFFER (STAUFFER et al., 1981, 1992), who also run lab experiments. A main purpose of this contribution is to show to what extent the Lange Bramke experiments provide the data for studying the hysteresis phenomenon in respect to runoff formation process.