title: Impact of laver treatment practices on the geoenvironmental properties of sediments in the Ariake Sea.
abstract: Since the 1970s, the catch of Tairagi and Agemaki shellfish that inhabit the shallow sediments of the Ariake Sea of Japan has fallen dramatically. This is partly accounted for by the Isahaya land reclamation dike project and by the increasingly frequent local red tides. A recent survey of local fisherman suggested that the decline in the shellfish harvest may also be due to the practice of laver treatment in the tidal flats of the Ariake Sea. We carried out field and laboratory investigations to determine whether the practice changes the geoenvironmental properties of the fine-grained sediments in the tidal flats. There were notable changes in the salt concentration, pH, and sulfide content between the sediments exposed to a laver treating agent and those without laver treatment. Based on these differences, we identified potential mechanisms by which the laver treating agent was transported into the sediments and influenced the sulfide levels.
authors.affiliation: Institute of Geotechnical Engineering, Southeast University, Si Pai Lou #2, Nanjing 210096, PR China. Electronic address: duyanjun@seu.edu.cn.
authors.forename: Yan Jun
authors.initials: YJ
authors.lastname: Du
authors.affiliation: Institute of Lowland Technology, Saga University, Honjo 1, Saga-Shi 840-8502, Japan.
authors.forename: Shigenori
authors.initials: S
authors.lastname: Hayashi
authors.affiliation: School of Naval Architecture, Ocean, and Civil Engineering, Shanghai Jiaotong University, 1954 Hua Shan Road, Shanghai 200030, PR China.
authors.forename: Shui-Long
authors.initials: SL
authors.lastname: Shen
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000187:drug effects; D005398:Fisheries / Q000592:standards; D019015:Geologic Sediments / Q000737:chemistry*; D057097:Harmful Algal Bloom; D007564:Japan; D009792:Oceans and Seas; D011156:Population Density; D012624:Seaweed; D012758:Shellfish; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity
chemical_list: D014874:Water Pollutants, Chemical
keywords: Ariake Sea; Salt content; Sediment; Seepage; Sulfide; pH