[A-HW22] 流域圏生態系における物質輸送と循環：源流から沿岸海域まで

[AHW22-04] リンの負荷量増加がサンゴの稚ポリプの骨格形成を阻害する

*飯島 真理子¹、安元 剛²、安元 純³、井口 亮¹、廣瀬 美奈⁴、鈴木 淳¹、渡部 終五² (1.国立研究開発法人　産業技術総合研究所、2.北里大学海洋生命科学部、3.琉球大学農学部、4.一般社団法人トロピカルテクノプラス)

キーワード：リン酸負荷量、サンゴ、リン吸着

The decline of coral reefs has become a serious global concern, with widespread coral bleaching being observed. The reduced recovery capacity of corals is highlighted, particularly attributing to the deterioration caused by excessive nutrient runoff, especially from agricultural discharges. This contributes to coral degradation, impacts biodiversity, increases water turbidity, and promotes bacterial growth, leading to coral diseases. While the impact of nitrogen is well-studied, the influence of phosphorus, often overlooked due to its low concentration in seawater, remains unclear.
This study investigates the long-term effects of phosphates on coral larvae, revealing that even at low concentrations, phosphates hinder skeletal formation. The experimental system demonstrates that increasing the volume of rearing seawater elevates the total phosphate concentration, emphasizing the importance of evaluating both concentration and total amount. The research underscores the potential detrimental effects of phosphates on coral growth, calling for a reevaluation of the impact of phosphates on coral reefs and providing significant implications for conservation efforts. Considering the significant influx of phosphorus into marine environments, the study proposes specific terrestrial measures to support sustainable coral reef conservation.