Abstract
On the coast of Japan, ca 3,000 fishing ports are present. The walls of
mooring space and breakwater, slipways, bottom and blocks provide
substrata for algae to attach, resulting in the formation of macroalgal
beds (sometimes including sea grass). These beds have been paid attention
to study algal succession, to use as nursery or feed of shellfish and to
enlarge such algal beds by researchers in the field of phycology, ecology
and coastal engineering. Among the above structures, slipways are the most
convenient sites to observe vegetation because of its horizontal
development of algal beds, safe accessibility and availability of clear
vegetational images in aerial photographs. Macroalgal beds range from
intertidal to upper subtidal zones on the slipways; zonation of
canopy-forming species or commercial algae including nori and kelp, urchin
barrens, or other positive and negative effects by the ambient factors
such as sedimentation and waste charge. Our preliminary survey also found
additional alteration of vegetation by presence of substructures of
slipways including as slip bar, pit, corner, wall, and grooves of blocks.
Sustainable, costless and easy monitoring of these beds may help local
residents understand the important productive communities on their closest
parts of their coasts.
