title: Effects of sedimentary sulfide on community structure, population dynamics, and colonization depth of macrozoobenthos in organic-rich estuarine sediments.
abstract: An annual field survey and in situ recolonization experiment revealed the effects of sedimentary sulfide (H2S) on macrozoobenthos in a eutrophic brackish lagoon. Species diversity was much lower throughout the year in muddy opportunist-dominant sulfidic areas. Mass mortality occurred during warmer months under elevated H2S levels. An enclosure experiment demonstrated that sedimentary H2S modified community composition, size structure, and colonization depth of macrozoobenthos. Species-specific responses to each sediment type (sand, sulfidic mud, and mud with H2S removed) resulted in changes in the established community structure. Dominant polychaetes (Hediste spp., Pseudopolydora spp., and Capitella teleta) occurred predominantly in a thin surface layer in the presence of H2S. On the other hand, organic-rich mud facilitated settlement of polychaete larvae if it does not contain H2S. These results demonstrate that sediment characteristics, including H2S level and organic content, were key structuring factors for the macrozoobenthic assemblage in organically polluted estuarine sediments.
authors.affiliation: Biological Institute, Graduate School of Science, Tohoku University, Aramaki-Aoba, Aoba-ku, Sendai 980-8578, Japan; National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan. Electronic address: gen@nies.go.jp.
authors.forename: Gen
authors.initials: G
authors.lastname: Kanaya
authors.affiliation: Emeritus Professor, Tohoku Gakuin University, Japan.
authors.forename: Tadayasu
authors.initials: T
authors.lastname: Uehara
authors.affiliation: Biological Institute, Graduate School of Science, Tohoku University, Aramaki-Aoba, Aoba-ku, Sendai 980-8578, Japan; EEC, Miyagi University of Education, 149 Aramaki-Aoba, Sendai 980-0845, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Kikuchi
mesh_terms: D000818:Animals; D044822:Biodiversity; D019015:Geologic Sediments / Q000737:chemistry*; D011077:Polychaeta; D011156:Population Density; D011157:Population Dynamics; D013440:Sulfides
chemical_list: D013440:Sulfides
keywords: Brackish lagoon; Community structure; Macrozoobenthos; Recolonization; Sediment; Sulfide