bryophyte

Bryophytes are a group of non-vascular land plants that includes mosses, liverworts, and hornworts. They lack true vascular tissue (xylem and phloem), have simple vegetative bodies, and are generally small and ground-hugging. Bryophytes commonly form mats or cushions in moist, shaded habitats such as soil, rocks, tree bark, or peat bogs.

The bryophyte life cycle features alternation of generations with a dominant haploid gametophyte stage. The green, photosynthetic gametophyte is typically the most conspicuous life stage, while the diploid sporophyte grows from the gametophyte and is usually dependent on it. Water is essential for fertilization because sperm swim to archegonia. Spores produced by the sporophyte germinate into new gametophytes, continuing the cycle. Most bryophytes have stomata on the sporophyte’s capsule or associated tissues, though this feature varies among groups.

Bryophytes are classified into three phyla: Marchantiophyta (liverworts), Bryophyta (mosses), and Anthocerotophyta (hornworts). Liverworts are often thallose or leafy but lack true leaves and well-developed vascular tissue. Mosses have leafy gametophytes with root-like rhizoids and typically a stalked sporophyte with a capsule. Hornworts usually have a flattened thallus and a horn-shaped sporophyte that grows from the base of the gametophyte.

Ecologically, bryophytes are widespread, especially in moist and cool environments. They contribute to soil formation, moisture regulation, and nutrient cycling and play a significant role in peatland ecosystems, where Sphagnum species store carbon. They are often among the first organisms to colonize bare substrates and can serve as bioindicators of environmental conditions. Human uses include horticultural peat and traditional fuel in some regions.