Ascophyllum nodosum

Ascophyllum nodosum is a large, common brown algae (Phaeophyceae) in the family Fucaceae, being the only species in the genus Ascophyllum. It is seaweed of the northern Atlantic Ocean, also known as rockweed, Norwegian kelp, knotted kelp, knotted wrack or egg wrack. It is common on the north-western coast of Europe (from Svalbard to Portugal) including east Greenland and the north-eastern coast of North America.

Description

Ascophyllum nodosum has long fronds with large egg-shaped air bladders set in series at regular intervals in the frond and not stalked. The fronds can reach 2 m in length and are attached by a holdfast to rocks and boulders. The fronds are olive-brown in color and somewhat compressed but without a mid-rib.

Distribution

Ascophyllum nodosum is found mostly on sheltered sites on shores in the mid-littoral where it can become the dominant species in the intertidal zone. It is found widely in the north Atlantic and also in the north-western part of the Pacific near Kamchatka. It is particularly common on the north-western coasts of the British Isles and Brittany.

Uses

Ascophyllum nodosum is harvested for use in alginate, animal feed, fertilizer and horticulture. Other uses have been found in the cosmetics industry and in alternative medicine.

Ecology

Ascophyllum nodosum is a foundation species in the North Atlantic. This alga plays a key role in its environment by influencing the associated flora and fauna. It also provides food and shelter to a variety of organisms, including mollusks, crustaceans, and polychaetes.

Research

Research into Ascophyllum nodosum has been extensive and has concentrated on the plant's chemical composition, the use of the seaweed in agriculture and horticulture, and the effects of harvesting on the plant's populations.

See also

• Fucaceae
• Algae
• Intertidal zone