Water Budget and Physical Hydrology

Abstract

Some information on the behavior of karst aquifers can be obtained from quantitative consideration of water inputs and outputs during median and base-flow regimes. The textbook version of the hydrologic cycle distributes precipitation as an input term into three components: evapotranspiration, surface runoff, and infiltration. Infiltration water remains in storage and then replenishes surface flow during periods of low precipitation. In a mature karst aquifer there is no surface runoff, and infiltration is more complicated. Internal runoff from sinking streams, internal runoff through sinkholes, and diffuse infiltration through the soils are partitioned between an internal drainage system that has some of the water residing in smaller fractures and joints and some in larger conduits with an unknown distribution of storage volume between the various types of “porosity.”