Phreatic zone

The phreatic zone is located within a karst system under the water level ( karst water level ) part. In porous rock sulphate (gypsum) or carbonate rock (limestone ) are here hence the cavities ( pores, crevices, caves ) filled with water.

Above that is the vadose zone. In it, the air cavities, according to rainfall are temporarily filled with versickerndem or runoff water.

Level fluctuations

Due to the weather-related seasonal variation in rainfall and temperatures at the surface, there are short and medium term, due to climate shifts also to long-term shifts of the water balance in a karst area. This varies the karst water level, and in the strict sense of the extent of the phreatic zone. In its strictest sense, only the permanently submerged zone is called phreatic.