Bryophyte

Mosses are extremely important during the early stages of ecological succession. Succession begins with the generation of a new environment. This can occur, for example, by the formation of sand dunes, the exposure of land by deglaciation, or by the radical disturbance of a previously vegetated landscape as when an area is logged or burned by wildfire. In such cases, the ground becomes vegetated by the process of succession, during which various different plant communities dominate the site in turn. Because of their ability to reproduce asexually by fragmentation and gemmae combined with sexual reproduction, which produces enormous numbers of tiny, easily-dispersed spores, mosses play a vital role in being among the first colonizers of disturbed sites. They stabilize the soil surface, thereby reducing erosion, while at the same time reducing the evaporation of water, making more available for succeeding plants. Mosses are not an important source of food for vertebrate herbivores. Peat mosses are the dominant plants of extensive northern wetland areas, and are largely responsible for the development of bogs.

Most species of mosses are not of any direct economic importance, and none are a food source for humans. Peat mosses are economically the most important mosses. Peat mosses are an important source of fuel in some countries. Peat is abundant in northern regions and represents a vast reservoir of potential energy. In northern Europe, peat has historically been dried, and in some cases compressed into briquettes for use in fireplaces and stoves. In Ireland, peat is still extensively used for cooking. One great advantage of peat as a fuel is that it burns very cleanly. About 95% of peat harvested in Ireland is burned to generate electricity. Peat is also highly valued as a conditioner of inorganic soils. Because it absorbs large amounts of water readily, peat improves the water-holding capacity of soil. Peat mosses are characteristically acidic which prevents the growth of most bacteria. They have therefore been used by indigenous peoples for diapers, and during the World Wars, when bandages were in short supply, peat mosses were a commonly used antiseptic dressing for wounds.

In recent years, mosses have become important in monitoring the health of ecosystems, especially in relation to atmospheric contamination. Because bryophytes lack roots, many of their nutritional requirements are met by nutrients deposited from the atmosphere. Thus, they are sensitive indicators of atmospheric pollutants. Changes in the distributions of mosses (and lichens) are therefore an early-warning signal of serious effects of atmospheric pollution.