moslaag

Moslaag, or the moss layer, is the uppermost vegetative cover on the ground in many ecosystems, consisting mainly of moss species and other bryophytes that form a dense mat over soil, decaying wood, or rock. It develops in shaded, moist environments where mosses can absorb and retain water and reproduce by spores. The layer moderates the microclimate at the ground surface by reducing evaporation, buffering temperature fluctuations, and slowing runoff. It also stores water and contributes to soil organic matter as plant material decomposes. The moss layer provides habitat for microfauna and influences seedling establishment by shaping light availability and moisture.

Species composition varies with climate and substrate. In wetlands and boreal forests, Sphagnum mosses and other bryophytes such as Polytrichum or Hypnum are common; in drier sites, the layer is thinner and dominated by drought-tolerant species. The moslaag interacts with the underlying soil or litter layer and with vascular plant communities, forming part of the forest floor or tundra carpet.

Disturbances such as heavy trampling, drying, pollution, or nutrient enrichment can reduce moss cover and alter its community, sometimes with long recovery times. Because mosses are good indicators of moisture and air quality, the moss layer is often used in ecological monitoring and restoration to support hydrological function and biodiversity.