SOOS Educational Trail

A deep peat bog formed in the northern part which drains into Sooský Creek. In the undrained southern part, a large pond formed which was filled with rainwater as well as water from numerous mineral springs. Such conditions were suitable for a community of single-celled algae called diatoms. Diatoms form siliceous two-part chambers that look like little boxes with a lid and bottom. They live in fresh and salt water. They have two seasons of development during the year - spring and autumn. Every year, two layers of sediment – bergmehl – form on the bottom. This is how a vaulted diatomeous shield several meters thick formed in the Soos. The presence of saltwater diatoms is interesting here - they’re not found elsewhere in the area.

The lake long since disappeared but the mineral springs and gaseous carbon dioxide broke through the diatomeous shield and are still doing so. Where they break the surface small craters up to 80 cm wide and tens of centimeters deep have formed. Some of them hiss gaseous carbon dioxide (officially known as mofettes) while others form false mud volcanoes that gurgle water and mud. They fill with water during a rainfall and ice pyramids and columns form around them in the winter.

The ground here is saturated with salts from the mineral springs and when it's dry, there is a crystalline covering of Glauber salt, reddish iron oxides, and yellow and green crystals of various sulphates. There is so much salt that practically no plant life exists here, only the type that can withstand such an environment. Particular plant types that normally require a salty soil base can be found here. Two larger springs have been captured in the Soos area - the Imperial (Císařský) Spring is particularly good.