Suspended sediment concentrations during an ex-situ experiment on the effects of simulated deep-sea mining sediment plumes on the cold-water octocoral Dentomuricea aff. meteor in the Azores

We report the results of an aquaria-based experiment testing the effects of simulated sediment plumes generated during mining activities for the extraction of ferromanganese nodules in the Clarion-Clipperton Fracture Zone (CCFZ), northeastern equatorial Pacific Ocean, and seafloor massive sulfides from a hydrothermal vent field in the Azores, northeast Atlantic, on the physiology of the cold-water octocoral Dentomuricea aff. meteor. Coral fragments were exposed to five experimental treatments for a period of four weeks at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores): (1) suspended plumes of abyssal sediments from nodule fields at a concentration of 10 mg/l; (2) suspended plumes of abyssal sediments from nodule fields at a concentration of 50 mg/l; (3) hydrothermal polymetallic sulphide particles at a concentration of 10 mg/l; (4) hydrothermal polymetallic sulphide particles at a concentration of 50 mg/l; and (5) a control treatment with no sediment addition. Sediments were added in 12 h daily cycles. The concentration of suspended sediments in each aquaria were monitored twice a week by filtering seawater and weighing sediments.

本研究报道了一项基于水族箱的实验结果，该实验旨在探究赤道太平洋东北部克拉里昂-克利珀顿断裂带（Clarion-Clipperton Fracture Zone, CCFZ）铁锰结核开采活动所产生的模拟沉积物羽流，以及大西洋东北部亚速尔群岛热液喷口场的海底块状硫化物，对冷水八放珊瑚近流星齿柳珊瑚（Dentomuricea aff. meteor）生理状态的影响。珊瑚片段于亚速尔大学奥克阿诺斯（Okeanos）的深海实验室（DeepSeaLab）水族设施中，在五种实验处理组下暴露培养四周：(1) 结核区深渊沉积物悬浮羽流，浓度为10 mg/L；(2) 结核区深渊沉积物悬浮羽流，浓度为50 mg/L；(3) 浓度为10 mg/L的热液多金属硫化物颗粒；(4) 浓度为50 mg/L的热液多金属硫化物颗粒；(5) 无沉积物添加的空白对照组。沉积物以每日12小时的周期投加。研究人员每周通过过滤海水并称量沉积物的方式，对每个水族箱内的悬浮沉积物浓度进行两次监测。