title: Microscopic observation of symbiotic and aposymbiotic juvenile corals in nutrient-enriched seawater.
abstract: Symbiotic and aposymbiotic juvenile corals, which were grown in the laboratory from the gametes of the scleractinian coral Acropora digitifera and had settled down onto plastic culture plates, were observed with a microscope under different nutrient conditions. The symbiotic corals successfully removed the surrounding benthic microalgae (BMA), whereas the aposymbiotic corals were in close physical contact with BMA. The areal growth rate of the symbiotic corals was significantly higher than that of the aposymbiotic corals. The addition of nutrients to the culture seawater increased the chlorophyll a content in the symbiotic coral polyps and enhanced the growth of some of the symbiotic corals, however the average growth rate was not significantly affected, most likely because of the competition with BMA. The comparison between the symbiotic and aposymbiotic juvenile corals showed that the establishment of a symbiotic association could be imperative for post-settlement juvenile corals to survive in high-nutrient seawater.
authors: Faculty of Science, University of the Ryukyus, Japan. tanaka.yask@gmail.com
authors: Yasuaki
authors: Y
authors: Tanaka
authors: Akira
authors: A
authors: Iguchi
authors: Mayuri
authors: M
authors: Inoue
authors: Chiharu
authors: C
authors: Mori
authors: Kazuhiko
authors: K
authors: Sakai
authors: Atsushi
authors: A
authors: Suzuki
authors: Hodaka
authors: H
authors: Kawahata
authors: Takashi
authors: T
authors: Nakamura
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000502:physiology*; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D058086:Microalgae / Q000502:physiology*; D008853:Microscopy; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D012623:Seawater / Q000737:chemistry; D013559:Symbiosis; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D014874:Water Pollutants, Chemical; D002734:Chlorophyll; D010758:Phosphorus; D009584:Nitrogen; D000077194:Chlorophyll A