Coral reef ecosystems are important fishing grounds in tropical and subtropical areas and have been widely contaminated by chemicals. However, the current understanding of the pollution status and trophic transfer of exogenous chemicals in coral reef ecosystems is still limited. This study aims to characterize the occurrence of 16 priority polycyclic aromatic hydrocarbons (PAHs) in sediments, corals, and other biotas in the trophic-complex coral reef ecosystems in the Xisha and Nansha Islands of the South China Sea. PAH transfer characteristics in the highly diverse coral reef food webs were analyzed through stable isotope ratios and trophic magnification factors (TMFs). PAHs were observed in sediment and biota samples of both Xisha and Nansha coral reef ecosystems. The TMFs ranging from 0.46 to 2.18 for the Xisha food web indicate limited trophic transfer of PAHs, while those ranging from 1.07 to 5.25 for the Nansha food web indicate trophic magnification of PAHs. The octanol-water partition coefficient (Kow) of PAHs may positively influence the PAH biomagnification via accumulation along the trophic levels. This study provides new insights into PAH contamination patterns and their trophodynamic behaviour in highly diverse coral reef ecosystems, which can serve as a scientific basis for ecological risk assessment, biodiversity conservation, and coastal function management in global coral reef systems.

中文翻译：

---

南海珊瑚礁生态系统多环芳烃污染现状及营养转移

珊瑚礁生态系统是热带和亚热带地区重要的渔场，已被化学物质广泛污染。然而，目前对珊瑚礁生态系统中外源化学物质的污染状况和营养转移的认识仍然有限。本研究旨在描述南海西沙和南沙群岛营养复合珊瑚礁生态系统中沉积物、珊瑚和其他生物群中 16 种优先多环芳烃 (PAHs) 的存在情况。通过稳定同位素比和营养放大因子 (TMF) 分析了高度多样化的珊瑚礁食物网中的 PAH 转移特征。在西沙和南沙珊瑚礁生态系统的沉积物和生物群样本中都观察到了 PAHs。TMF 范围从 0.46 到 2。西沙食物网的 18 表示 PAHs 的营养转移有限，而南沙食物网的 1.07 至 5.25 表示 PAHs 的营养放大。PAHs 的辛醇-水分配系数 (Kow) 可能通过沿营养级的积累对 PAH 生物放大产生积极影响。本研究为高度多样化的珊瑚礁生态系统中多环芳烃污染模式及其营养动力学行为提供了新的见解，可为全球珊瑚礁系统的生态风险评估、生物多样性保护和海岸功能管理提供科学依据。PAHs 的辛醇-水分配系数 (Kow) 可能通过沿营养级的积累对 PAH 生物放大产生积极影响。本研究为高度多样化的珊瑚礁生态系统中多环芳烃污染模式及其营养动力学行为提供了新的见解，可为全球珊瑚礁系统的生态风险评估、生物多样性保护和海岸功能管理提供科学依据。PAHs 的辛醇-水分配系数 (Kow) 可能通过沿营养级的积累对 PAH 生物放大产生积极影响。本研究为高度多样化的珊瑚礁生态系统中多环芳烃污染模式及其营养动力学行为提供了新的见解，可为全球珊瑚礁系统的生态风险评估、生物多样性保护和海岸功能管理提供科学依据。