Coral-fish tank-based nutrient interactions

To investigate the potential nutrient enrichment of corals by fish wastes, Acropora kenti, Pocillopora verrucosa, Poritesa lutea and Platygyra daedalea colonies were collected from the GBR in Feb 2022, then returned to AIMS's National Sea Simulator. Coral were sampled for protein/symbiont density, then fragmented into smaller (~10g) pieces and aloowed to recover and acclimate to the captive conditions for 1.5 months. Corals were then randomally allocated to treatments where they were either 1) kept with a school of 10 juvenile Chromis viridis fed a pelleted diet, 2) supplied filtered water from a tank housing C. viridis, 3) fed live feeds (enriched Artemia/rotifers and microalgae mix) whilst maintained with C. viridis, 4) supplied only with the live feeds, 5) supplied with a pelleted fish diet without C. viridis, and 6) not supplied feeds and without C. viridis, with four replicate tanks per treatment. During the experiment survival of corals was monitored, growth was measured using bouyant weight and photosynthetic efficiency tracked using dark adapated maximum quantum yield (Fv/Fm). At the end of the experiment, a subset of the samples were frozen and tissue stripped using high-pressure air and filtered seawater. The resulting tissue slurry was homogenised, then used to measure protein contect via a BCA assay and symbiont density using a BD Acurri C6 Flow Cytometer. Water quailty samples were taken weekly throughout the experiment, and analysed for NH4, NO2, NO3, PO4, DOC, PN and PC. Fish were anaethatised using Aqui-S at the end of the experiment and weighed.

为探究鱼类排泄物对珊瑚的潜在营养富集效应，研究团队于2022年2月从大堡礁（Great Barrier Reef，GBR）采集了肯特轴孔珊瑚（Acropora kenti）、疣状杯形珊瑚（Pocillopora verrucosa）、黄孔珊瑚（Porites lutea，原文疑似笔误为Poritesa lutea）、戴达勒亚扁脑珊瑚（Platygyra daedalea）的群落样本，随后将样本移送至澳大利亚海洋科学研究所（Australian Institute of Marine Science, AIMS）的国家海洋模拟系统（National Sea Simulator）中暂养。首先对珊瑚样本开展蛋白质含量与共生藻密度的基线采样检测，随后将其切割为约10克的小块，在人工养殖条件中恢复驯化1.5个月。之后将珊瑚随机分配至6组处理：1）与10尾幼体蓝绿光鳃鱼（Chromis viridis）共养，投喂配合颗粒饲料；2）接收饲养蓝绿光鳃鱼的水箱过滤水；3）与10尾幼体蓝绿光鳃鱼共养，同时投喂营养强化活饵（卤虫/轮虫与微藻混合饵料）；4）仅投喂上述活饵；5）投喂配合颗粒饲料但不饲养蓝绿光鳃鱼；6）不投喂饲料且不饲养蓝绿光鳃鱼，每组设置4个重复养殖缸。实验期间，监测珊瑚存活率，采用浮力称重法测量珊瑚生长速率，并通过暗适应最大量子产额（Fv/Fm）追踪光合效率。实验结束后，选取部分样本进行冷冻保存，随后利用高压空气与过滤海水剥离珊瑚组织，将得到的组织匀浆均质化，采用二喹啉甲酸法（BCA法）测定蛋白质含量，通过BD Acurri C6流式细胞仪检测共生藻密度。实验全程每周采集水质样本，分析氨氮（NH₄）、亚硝酸盐（NO₂）、硝酸盐（NO₃）、磷酸盐（PO₄）、溶解有机碳（DOC）、颗粒态氮（PN）与颗粒态碳（PC）含量。实验结束后，使用Aqui-S麻醉鱼类并称量其体重。