title: Short-term dynamics of cyanobacterial toxins (microcystins) following a discharge from a coastal reservoir in Isahaya Bay, Japan.
abstract: Freshwater cyanobacteria produce highly toxic substances such as microcystins (MCs), and water containing MCs is often discharged to downstream and coastal areas. We conducted field monitoring in Isahaya Bay to clarify the short-term dynamics of MCs discharged from a reservoir following a cyanobacteria bloom in the warm season. MCs were detected in the seawater of the bay (max. 0.10 μg L(-1)), and were deposited on the sea floor, with the MC content of the surface sediment increasing by approximately five times (0.11±0.077-0.53±0.15 μg kgww(-1), mean±SD) at the four stations near the reservoir drainage gate before and after the discharge. The MCs was then transported from the mouth of the bay by tidal currents during the period of the study. Therefore, the MCs were moved away from the closed water area where the cyanobacteria blooms, and spread throughout the coastal area.
authors.affiliation: Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto 862-8502, Japan. Electronic address: umehara84@gmail.com.
authors.forename: Akira
authors.initials: A
authors.lastname: Umehara
authors.affiliation: Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto 862-8502, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Komorita
authors.affiliation: Faculty of Institute for Advanced Study, Kyushu University, 744 Motooka, Fukuoka 819-0395, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Tai
authors.affiliation: Department of Medical Technology, Kumamoto Health Science University, 325 Izumi-machi, Kumamoto 861-5598, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto 862-8502, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Orita
authors.affiliation: Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto 862-8502, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tsutsumi
mesh_terms: D001427:Bacterial Toxins / Q000032:analysis*; D061006:Bays; D000458:Cyanobacteria; D000087522:Cyanobacteria Toxins; D004784:Environmental Monitoring; D005068:Eutrophication; D005618:Fresh Water / Q000382:microbiology; D007564:Japan; D008387:Marine Toxins / Q000032:analysis*; D052998:Microcystins / Q000032:analysis*; D012621:Seasons; D012623:Seawater / Q000382:microbiology
chemical_list: D001427:Bacterial Toxins; D000087522:Cyanobacteria Toxins; D008387:Marine Toxins; D052998:Microcystins; C078588:microcystin
keywords: Discharge; Dynamics; Isahaya Bay; Microcystin; Reservoir; Sedimentation