Subtropical meiobenthic nematode communities in Victoria Harbour, Hong Kong

摘要

Owing to their sessile mode of life, marine benthic communities have long been used as bioindicators for monitoring coastal pollution (Coull and Chandler, 1992; Elias and Bremec, 1994; Gesteira et al., 2003). A decline of faunal species and abundance, and/or changes in species composition, can be attributed to response to pollutants in the sediment. Macrofauna has mostly been studied in pollution monitoring because of their relatively larger size ( > 0.5 mm), but in recent years there has been an increase in the use of smaller-sized organisms such as the meiofauna (0.038-0.5 mm) as the target organisms (Coull and Chandler, 1992; Giere, 1993; Schratzberger et al., 2000). Comparing with macrofauna, meiofauna offers many advantages as indicators for pollution monitoring. Specimens of meiofauna, especially nematodes, can be collected in a relatively small volume of sediment (Schratzberger et al., 2000). They are also ubiquitously distributed and highly diverse in marine sediments. While macrofauna usually has a planktonic larval stage, meiobenthic nematodes have a direct development phase with short life-cycles of one to three months, so that changes in community structure can be readily observed in short-term studies (Heip et al., 1985; Higgins and Thiel, 1988). Many studies also showed that meiofauna is an important component in marine benthic ecosystems because of their small size, high abundance and fast turnover rates (Heip et al., 1985; Coull, 1999), and plays an important role in marine benthic food chains (Gee, 1989).