title: Can the algicidal material Ca-aminoclay be harmful when applied to a natural ecosystem? An assessment using microcosms.
abstract: We assessed the ability of an artificial clay (Ca-aminoclay) to suppress harmful algal bloom species (HABs) such as Cochlodinium polykrikoides and Chattonella marina and investigated the ecological responses in the closed and open microcosm systems. The Ca-aminoclay induced rapidly and selectively cell lysis in the HABs. However, applying Ca-aminoclay could cause adverse impacts in terms of biological and environmental changes. The bacterioplankton abundance increased and then, the abundances of heterotrophic nanoflagellates and ciliates increased rapidly. Extremely poor environmental conditions such as increase in nutrients and development of anoxic conditions were sustained continuously in a closed system, while the environmental conditions in open systems deteriorated before recovering to the initial conditions. We evaluated the potential for the occurrence of a bloom of another phytoplankton after HABs had been controlled using the Ca-aminoclay. The Ca-aminoclay controlled blooms of Chattonella marina in mixed cell cultures containing a Tetraselmis chui. However, T. chui increased over time and then bloomed. Therefore, caution should be taken when considering the direct application of Ca-aminoclay in natural environments even though it offers the rapid removal of HABs.
authors.affiliation: South Sea Institute, Korea Institute of Ocean Science & Technology, Geoje 656-830, Republic of Korea. Electronic address: diatoms@kiostac.kr.
authors.forename: Seung Won
authors.initials: SW
authors.lastname: Jung
authors.affiliation: Department of Life Science, Sangmyung University, Seoul 110-743, Republic of Korea.
authors.forename: Suk Min
authors.initials: SM
authors.lastname: Yun
authors.affiliation: Korea Institute of Coastal Ecology, Incoperation, Bucheon 421-742, Republic of Korea.
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Yoo
authors.affiliation: South Sea Institute, Korea Institute of Ocean Science & Technology, Geoje 656-830, Republic of Korea; Department of Life Science, Hanyang University, Seoul 133-791, Republic of Korea.
authors.forename: Li
authors.initials: L
authors.lastname: Zhun
authors.affiliation: South Sea Institute, Korea Institute of Ocean Science & Technology, Geoje 656-830, Republic of Korea.
authors.forename: Pung-Guk
authors.initials: PG
authors.lastname: Jang
authors.affiliation: South Sea Institute, Korea Institute of Ocean Science & Technology, Geoje 656-830, Republic of Korea. Electronic address: oceanlim@kiost.ac.kr.
authors.forename: Dhong-Il
authors.initials: DI
authors.lastname: Lim
authors.affiliation: Department of BioNano Technology, Gachon University, Seongnam 461-701, Republic of Korea.
authors.forename: Young-Chul
authors.initials: YC
authors.lastname: Lee
authors.affiliation: Advanced Nano-Surface Research Group, Korea Basic Science Institute, Daejeon 305-333, Republic of Korea.
authors.forename: Hyun Uk
authors.initials: HU
authors.lastname: Lee
authors.affiliation: South Sea Institute, Korea Institute of Ocean Science & Technology, Geoje 656-830, Republic of Korea.
authors.forename: Taek-Kyun
authors.initials: TK
authors.lastname: Lee
authors.affiliation: South Sea Institute, Korea Institute of Ocean Science & Technology, Geoje 656-830, Republic of Korea.
authors.forename: Jinbee
authors.initials: J
authors.lastname: Heo
authors.affiliation: Department of Life Science, Sangmyung University, Seoul 110-743, Republic of Korea.
authors.forename: Jin Hwan
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Life Science, Hanyang University, Seoul 133-791, Republic of Korea.
authors.forename: Myung-Soo
authors.initials: MS
authors.lastname: Han
mesh_terms: D000538:Aluminum Silicates / Q000633:toxicity*; D002118:Calcium / Q000737:chemistry; D000077215:Clay; D017753:Ecosystem; D057097:Harmful Algal Bloom / Q000187:drug effects*; D010575:Pesticides / Q000633:toxicity*; D010933:Plankton / Q000737:chemistry; D014871:Water Microbiology; D014876:Water Pollution / Q000009:adverse effects
chemical_list: D000538:Aluminum Silicates; D010575:Pesticides; D002118:Calcium; D000077215:Clay
keywords: Algicidal material; Ca-aminoclay; Harmful algal blooms; Microcosm experiments