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Vol. 41 No. 2, 2002
The Development of Subtidal Fouling Assemblages on Artificial Structures in Keelung Harbor, Northern Taiwan
Hsing-Juh Lin1 and Kwang-Tsao Shao2,*
1Department of Botany, National Chung Hsing University, Taichung, Taiwan 402
2Institute of Zoology, Academia Sinica, Taipei, Taiwan 115
Hsing-Juh Lin and Kwang-Tsao Shao (2002)
Effects of substratum, its submersion season, and submersion period on
the development of subtidal fouling assemblages were examined for a
period of 18 mo in a subtropical harbor. Four types of artificial
surfaces, including steel, stainless steel, cathodically protected
steel, and concrete, were initially submersed in fall and spring,
respectively, and sampled every 3-6 mo. There is little evidence that
type of substratum influenced the development of fouling assemblages.
However, richer taxa and greater biomass of fouling assemblages
occurred on spring-than on fall-submersed plates. Fouling biomass
reached a maximum at the end of the study period, but the taxa were
richest at the end of 12 months. Classification and ordination analyses
show that the species compositions of fouling assemblages were
structured by submersion season and submersion period of the
substratum, but not by the nature of the substratum itself. The oyster,
Crassostrea gigas,
dominated spring plates throughout the study period, but the
assemblages on fall plates were highly variable. This indicates that
submersion season and submersion period of the substratum are more
important than type of substratum in the development of subtidal
fouling assemblages. However, the abundance and species composition on
spring and fall plates became less dissimilar by the end of 12 mo. This
suggests that development takes the same course even with different
seasons of submersion. It is likely that the fouling species acted in
individualistic manners, and the assemblages were composed simply of
fouling species which arrived at that time. Our results demonstrate
that the developmental process is greatly affected by seasonal
fluctuations in larval abundance and historical components on a
substratum.
Key words: Substratum, Submersion season, Submersion period, Crassostrea gigas.
*Correspondence: Tel: 886-2-27899545. Fax: 886-2-27883463. E-mail: zoskt@gate.sinica.edu.tw
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