Effects of different feeding habits of three bivalve species on sediment characteristics and benthic diatom abundance

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 299:67-78 (2005) - doi:10.3354/meps299067 Effects of different feeding habits of three bivalve species on sediment characteristics and benthic diatom abundance Gen Kanaya1,*, Ei Nobata2, Terumasa Toya2, Eisuke Kikuchi1 1Center for Northeast Asian Studies, Tohoku University, Kawauchi, Aoba-ku, Sendai 980-8576, Japan2Biological Institute, Graduate School of Science, Tohoku University, Aramaki-aza-Aoba, Aoba-ku, Sendai 980-8578, Japan *Email: gen@cneas.tohoku.ac.jp ABSTRACT: To reveal the feeding habits of 3 bivalve species and the effects on the sediment and benthic diatoms, a field experiment was conducted in the estuarine Gamo lagoon, Japan, using enclosures stocked with bivalves. The surface-deposit feeder Macoma contabulata reduced silt–clay, total nitrogen, and total organic carbon content and the δ13C value of the sediment, while the surface-deposit feeder Nuttallia olivacea and the suspension feeder Ruditapes philippinarum did not. The surface-deposit feeders reduced phytobenthic biomass (chlorophyll a, chl a) and diatom density at thesediment surface and increased the C/N ratios of the sediment. In contrast, R. philippinarum increased chl a although it decreased benthic diatoms, suggesting the promotion of microalgal growth other than diatoms. All the bivalve species reduced the densities of the dominant diatom species differently, and M. contabulata decreased the species richness. Multidimensional scaling and 1-way analysis of similarity revealed that the bivalves specifically modified the abundances and composition of the diatoms in relation to their feeding habits, while the relative diatom species abundances hardly changed. These data suggest that the bivalves show little selectivity when they ingest benthic diatoms. A 2-source mixing model using δ13C values revealed that benthic diatoms were the more important carbon source (>69%) for the deposit-feeding bivalves, both in natural habitats and in enclosures. In contrast, R. philippinarum obtained 61% carbon from suspended solids (SS) in the natural habitat, whereas in the enclosures it obtained 62% carbon from benthic diatoms. The dietary change of this species might be related to the supply of SS and resuspended sediment. KEY WORDS: Infaunal bivalves · Feeding habit · Bioturbation · Benthic diatom · Sediment · Stable isotope Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 299. Online publication date: September 01, 2005 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2005 Inter-Research.