Peat moss ("Sphagnum" sp.) is an excellent water store. They die off at the point where they stand in water and continue growing above this point. The underlying dead particles are continually compressed downwards by the new growth from above. Thus, over a period of several ten thousands of centuries, provided that the climate and environmental conditions are in order, smaller or larger layers of peat are created. The peat layer in Gmös is, however, not exceptionally thick, as the peat mosses could not compete with the pressure applied and could therefore not turn into an ombrotrophic bog.