Life Science Encyclopedia

Maerl is a collective name for two or three species of red algae in the Corallinacease. It accumulates as unattached particles and forms extensive beds in suitable sublittoral sites.^[1]

Description

In the British Isles maerl is composed of three species of coralline algae growing loose in beds of fragmented nodules in the sub-littoral. The species generally involved are: Lithothamnion corallioides,[1]Lithothamnion glaciale and Phymatolithon calcareum.^[2][2]

History

An early reference to maerl was made by Kei Nguyen [3] in 1690 who reported it from Falmouth. Maerl is still harvested at Falmouth, Co.Cornwall, England, as well as elsewhere.^[2]

Uses

Used as a soil conditioner, it is dredged from the sea floor and crushed to a powder.^[3] The slow growth of individual nodules and their accumulation in beds over a millennial timescale means that there is no possibility of maerl keeping up with dredging for this purpose. Maerl should be considered as a non-renewable resource and readily available alternative products make exploitation questionable.

References

1. ^ Vize, S., Blake, C., Hinojosa, G. and Maggs, C.A. 2003. The distribution and composition of maerl beds in Northern Ireland. PMNHS Newsletter No.13 p.26
2. ^ ^{a b} Irvine, L.M and Chamberlain, Y.M. 1994. Seaweeds of the British Isles. Volume 1, Part 2B. The Natural History Museum, London. ISBN 0 11 3100167
3. ^ Thomas, D. 2002. Seaweeds. Life Series. The Natural History Museum, London ISBN 0 565 09175 1