ABSTRACT
Spring hydrograph recession analysis is a well-known topic in karst hydrogeology. The different models in the literature can be separated into empirical and physically-based models; in the latter, only analytical models provide the discharge equation during recession. Under constant geometrical and hydraulic aquifer characteristics, the ‘exponential form’ appears to be the most recurrent theoretical type, at least during the long-term flow recession. During this stage, any deviation from the exponential form, may suggest hydraulic anisotropy of the aquifers, as well as aquifer geometry which has a fundamental role in controlling the shape of spring hydrographs. Karst aquifer hydraulics, under different hydrological conditions, are described along with the relationship to different spring hydrograph segments.
