Zosteraceae

Zosteraceae is a family of flowering plants in the order Alismatales, commonly known as seagrasses. The family comprises two genera, Zostera and Phyllospadix, with several species distributed in shallow marine environments around the world. Representative species include Zostera marina (eelgrass) and Phyllospadix scouleri (scouler’s surfgrass). These plants are marine angiosperms adapted to submerged life and often form extensive underwater meadows that stabilize sediments and support coastal ecosystems.

Morphology and growth: Members of Zosteraceae are rhizomatous perennial herbs. They have long, linear, blade-like leaves that arise from underground rhizomes and extend into the water column. Roots develop from the rhizomes and help anchor the plants in soft sediments. Flowers are small and produced on specialized flowering shoots; many species are dioecious or have inconspicuous bisexual flowers. Pollination occurs in water, and vegetative propagation through rhizomes contributes to meadow expansion and persistence.

Distribution and habitat: Zosteraceae species are found in shallow coastal seas worldwide, ranging from temperate to tropical regions. They occupy bays, estuaries, coastal lagoons, and nearshore habitats where light is sufficient for photosynthesis and sediments are relatively stable.

Ecology and importance: Seagrass meadows formed by Zosteraceae provide critical ecosystem services. They stabilize sediments, reduce shoreline erosion, improve water quality by filtering nutrients, and create habitat and nursery grounds for a variety of invertebrates and fish. They also store carbon in sediments, contributing to blue carbon ecosystems.

Conservation: Seagrass beds are vulnerable to threats such as coastal development, dredging, boating damage, nutrient pollution, and climate change. Declines have prompted habitat protection, water quality management, and restoration efforts, including transplantation and protective measures for intact meadows.