日本地球惑星科学連合2019年大会

講演情報

[E] ポスター発表

セッション記号 A (大気水圏科学) » A-HW 水文・陸水・地下水学・水環境

[A-HW22] 流域の物質輸送と栄養塩循環-源流域から沿岸海域まで-

2019年5月30日(木) 15:30 〜 17:00 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:小林 政広(国立研究開発法人森林研究・整備機構 森林総合研究所)、吉川 省子(農業・食品産業技術総合研究機構 農業環境変動研究センター)、安元 純(琉球大学 農学部 地域農業工学科)、Adina Paytan(University of California Santa Cruz)

[AHW22-P01] 過剰リン酸塩はコユビミドリイシ稚サンゴの骨格形成を阻害する

飯島 真理子1、*安元 剛1安元 純2廣瀬 美奈3神保 充1渡部 終五1 (1.北里大学海洋生命科学部、2.琉球大学農学部、3.トロピカルテクノプラス)

キーワード:リン酸塩、石灰化

Coral reef degradation resulting from various types of local stress on corals such as excessive nutrient enrichment in and gravel inflow into coastal waters is of an increasing global concern. Because tropical and subtropical seawaters are generally poor in nutrients and thus oligotrophic, these stresses are thought to result in the decline of environments favorable to coral growth. Inorganic phosphates have been especially considered to possibly inhibit the formation of coral skeleton. Despite many studies available on the effects of nutrients on corals, a clear consensus for how nutrients exert deteriorative effects on the corals has not been established satisfactorily. Recently, we found that biogenic polyamines react with carbon dioxide (CO2) and accelerate an aragonite formation of calcium carbonate (CaCO3) in seawater. In this study, we examined the effects of phosphates and nitrates on in vitro aragonite formation of CaCO3 by using biogenic polyamines and in vivo aragonite formation of juvenile coral Acropora digitifera skeletons, showing that phosphates clearly inhibited both in vitro and in vivo CaCO3 formations at similar concentrations. In contrast, nitrates inhibited neither in vitro aragonite formation of CaCO3 nor in vivo aragonite formation of juvenile coral skeletons. These findings indicate that phosphates have a detrimental effect on bioinorganic coral calcification. Furthermore, the findings that phosphate enrichment inhibits coral skeleton formation led us to conclude that enriched phosphate is adsorbed on juvenile coral skeleton surface and inhibits inorganically normal development of juvenile coral skeleton.