Discharging groundwater creates unique conditions.
Springs are formed where groundwater is discharged from the soil and reaches the surface, usually in areas where the land surface and the groundwater level are close to each other. Typical locations for springs include lower slopes of eskers and border zones between peatlands and mineral soils.
Many different types of springs exist. Springs can have an open water basin at their source or they can start to immediate flow as a brook. Some springs don’t have an open water surface at all; instead, the groundwater discharged creates a wet vegetated habitat. There are tens of thousands of known springs in Finland. Not all of them are located yet.
Conditions in spring areas differ greatly from other forest areas. The constantly emerging groundwater keeps the spring unfrozen through winter and cool during summer. As frost-free habitats, springs provide a haven for species that can’t tolerate freezing temperatures.
Springs affect the moisture levels and temperatures of their immediate surroundings too. This is reflected in the composition of tree species and other vegetation that grow near springs. Small-scale mires often develop around a spring. These special conditions make springs and their immediate surroundings perfect habitats for species which can’t survive elsewhere in the forest. This makes springs valuable for biodiversity.
Springs and the environment near them are protected areas; forestry operations are not carried out in them. Leaving springs untouched promotes biodiversity and safeguards groundwater quality. Degraded springs can be enhanced by restoring their natural hydrology.