ALBERT

Description: We report the results of a land-based experiment testing the cumulative effects of copper (Cu) exposure and ocean acidification (OA). Corals were obtained as by-catch during an experimental long-line fisheries campaign (CONDOR monitoring program, Okeanos-University of the Azores) on the Condor Seamount (38°54′N, 29°05′W), Azores Archipelago, at 200 m depth in October 2019. The experiment was undertaken at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores) where corals were exposed to four OA/Cu-contamination scenarios: (1) ambient pCO2/pH level as measured in situ conditions (385 μatm/ pH 8.09); (2) high pCO2/reduced pH (IPCC RCP8.5 scenario, 1000 μatm/ pH 7.73); (3) ambient pCO2/pH level and additional Cu concentration (60 µg/l); (4) high pCO2/reduced pH and additional Cu concentration (60 µg/l). The pH/pCO2 modification was achieved by bubbling seawater with either pure CO2 (to increase pCO2) or CO2 low air (to decrease pCO2). The copper concentration used in this experiment followed a trial simulating a polymetallic particles plume release during a potential deep-sea mining event. This sublethal concentration was found to be the highest copper concentration dissolved in seawater. Seawater physical-chemical parameters were measured daily in each chamber. Temperature, pH and oxygen saturation were measured manually in each aquaria every day using a Mettler-Toledo S8 glass and a Fibox4 (PreSens) with an Oxygen Probe PSt3.

Description: We report the results of a land-based experiment testing the cumulative effects of copper (Cu) exposure and ocean acidification (OA). Corals were obtained as by-catch during experimental long-line fisheries campaigns on board R/V "Arquipélago" (ARQDAÇO monitoring program, University of the Azores) at Baixa de São Mateus at 185 m depth in April 2019. The experiment was undertaken at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores) where corals were exposed to four OA/Cu-contamination scenarios: (1) ambient pCO2/pH level as measured in situ conditions (385 μatm/ pH 8.09); (2) high pCO2/reduced pH (IPCC RCP8.5 scenario, 1000 μatm/ pH 7.73); (3) ambient pCO2/pH level and additional Cu concentration (60 µg/l); (4) high pCO2/reduced pH and additional Cu concentration (60 µg/l). The pH/pCO2 modification was achieved by bubbling seawater with either pure CO2 (to increase pCO2) or CO2 low air (to decrease pCO2). The copper concentration used in this experiment followed a trial simulating a polymetallic particles plume release during a potential deep-sea mining event. This sublethal concentration was found to be the highest copper concentration dissolved in seawater. Metabolic (CA and Hsp70), oxidative damage (SOD, MDA) and detoxification (GST) biomarkers were measured in 4 corals from each treatment at the end of the experiment, using a multiplate spectrophotometer reader.

Description: We conducted a medium-term (4 months) multiple stressor experiment with the cold-water coral Desmophyllum dianthus under future environmental conditions (IPCC RCP 8.5 scenarios for 2100), and sediment plumes generated during the potential extraction of seafloor massive sulphides. The experiment followed a two-step approach, where during the first 3 months, corals were exposed to four different treatments combining predicted scenarios of ocean acidification (pCO2/pH) and food availability. Two levels of pCO2 conditions were considered: natural habitat present day conditions (~500 µatm, 720 m depth) and IPCC RCP8.5 scenario (1000 µatm; IPCC, 2019), corresponding to pHT values of 7.93 and 7.66, respectively. In addition, two food availability regimes were recreated: high frequency of feeding (food delivered twice a day / 7 days a week) and low frequency of feeding (food delivered every other day). There were six replicate 13 L aquaria per treatment (4 D. dianthus per aquaria) at a temperature of 10.5 ± 0.1 ºC. During the fourth month of the experiment, suspended polymetallic sulphide particles generated during potential mining activities were added to half of the aquaria under the climate change scenarios at a concentration of 10 mg/l, making 8 treatments in a fully crossed experimental design for the 3 factors tested (OA, food, mining particles). Measurements of respiration were made at different times during the experiments: T0 (immediately before the start of the experiment), 2, 4, 9 and 14 weeks, using an oxygen meter Fibox4 with PSt3 sensors (PreSens, Germany). Coral respiration rates were normalized to the coral skeletal surface area.

Description: 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. The surface area of the coral tissue lost during the experiment was quantified using photographs of the coral fragments and ImageJ software. Measurements were made every week for a period of 4 weeks.

Description: We report the results of a land-based experiment testing the cumulative effects of copper (Cu) exposure and ocean acidification (OA). Corals were obtained as by-catch during an experimental long-line fisheries campaign (CONDOR monitoring program, Okeanos-University of the Azores) on the Condor Seamount (38°54′N, 29°05′W), Azores Archipelago, at 200 m depth in October 2019. The experiment was undertaken at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores) where corals were exposed to four OA/Cu-contamination scenarios: (1) ambient pCO2/pH level as measured in situ conditions (385 μatm/ pH 8.09); (2) high pCO2/reduced pH (IPCC RCP8.5 scenario, 1000 μatm/ pH 7.73); (3) ambient pCO2/pH level and additional Cu concentration (60 µg/l); (4) high pCO2/reduced pH and additional Cu concentration (60 µg/l). The pH/pCO2 modification was achieved by bubbling seawater with either pure CO2 (to increase pCO2) or CO2 low air (to decrease pCO2). The copper concentration used in this experiment followed a trial simulating a polymetallic particles plume release during a potential deep-sea mining event. This sublethal concentration was found to be the highest copper concentration dissolved in seawater. Measurements of respiration were made immediately before the start of the experiment (T0) and after 9 days (T9, end of the experiment), when corals started to show tissue necrosis, using an oxygen meter Fibox4 with a PSt3 sensor (PreSens, Germany). Coral respiration rates were normalized to the coral surface area.

Description: We report the results of a land-based experiment testing the cumulative effects of copper (Cu) exposure and ocean acidification (OA). Corals were obtained as by-catch during experimental long-line fisheries campaigns on board R/V "Arquipélago" (ARQDAÇO monitoring program, University of the Azores) at Baixa de São Mateus at 185 m depth in April 2019. The experiment was undertaken at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores) where corals were exposed to four OA/Cu-contamination scenarios: (1) ambient pCO2/pH level as measured in situ conditions (385 μatm/ pH 8.09); (2) high pCO2/reduced pH (IPCC RCP8.5 scenario, 1000 μatm/ pH 7.73); (3) ambient pCO2/pH level and additional Cu concentration (60 µg/l); (4) high pCO2/reduced pH and additional Cu concentration (60 µg/l). The pH/pCO2 modification was achieved by bubbling seawater with either pure CO2 (to increase pCO2) or CO2 low air (to decrease pCO2). The copper concentration used in this experiment followed a trial simulating a polymetallic particles plume release during a potential deep-sea mining event. This sublethal concentration was found to be the highest copper concentration dissolved in seawater. Measurements of respiration were made immediately before the start of the experiment (T0) and after 9 days (T9, end of the experiment), when corals started to show tissue necrosis, using an oxygen meter Fibox4 with a PSt3 sensor (PreSens, Germany). Coral respiration rates were normalized to the coral surface area.

Description: We report the results of a land-based experiment testing the cumulative effects of copper (Cu) exposure and ocean acidification (OA). Corals were obtained as by-catch during experimental long-line fisheries campaigns on board R/V "Arquipélago" (ARQDAÇO monitoring program, University of the Azores) at Baixa de São Mateus at 185 m depth in April 2019. The experiment was undertaken at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores) where corals were exposed to four OA/Cu-contamination scenarios: (1) ambient pCO2/pH level as measured in situ conditions (385 μatm/ pH 8.09); (2) high pCO2/reduced pH (IPCC RCP8.5 scenario, 1000 μatm/ pH 7.73); (3) ambient pCO2/pH level and additional Cu concentration (60 µg/l); (4) high pCO2/reduced pH and additional Cu concentration (60 µg/l). The pH/pCO2 modification was achieved by bubbling seawater with either pure CO2 (to increase pCO2) or CO2 low air (to decrease pCO2). The copper concentration used in this experiment followed a trial simulating a polymetallic particles plume release during a potential deep-sea mining event. This sublethal concentration was found to be the highest copper concentration dissolved in seawater. Seawater physical-chemical parameters were measured daily in each chamber. Temperature, pH and oxygen saturation were measured manually in each aquaria every day using a Mettler-Toledo S8 glass and a Fibox4 (PreSens) with an Oxygen Probe PSt3.

Description: We conducted a medium-term (4 months) multiple stressor experiment with the cold-water coral Desmophyllum dianthus under future environmental conditions (IPCC RCP 8.5 scenarios for 2100), and sediment plumes generated during the potential extraction of seafloor massive sulphides. The experiment followed a two-step approach, where during the first 3 months, corals were exposed to four different treatments combining predicted scenarios of ocean acidification (pCO2/pH) and food availability. Two levels of pCO2 conditions were considered: natural habitat present day conditions (~500 µatm, 720 m depth) and IPCC RCP8.5 scenario (1000 µatm; IPCC, 2019), corresponding to pHT values of 7.93 and 7.66, respectively. In addition, two food availability regimes were recreated: high frequency of feeding (food delivered twice a day / 7 days a week) and low frequency of feeding (food delivered every other day). There were six replicate 13 L aquaria per treatment (4 D. dianthus per aquaria) at a temperature of 10.5 ± 0.1 ºC. During the fourth month of the experiment, suspended polymetallic sulphide particles generated during potential mining activities were added to half of the aquaria under the climate change scenarios at a concentration of 10 mg.L-1, making 8 treatments in a fully crossed experimental design for the 3 factors tested (OA, food, mining particles). Seawater physical-chemical parameters were measured daily in each aquarium. Temperature and pH were measured manually in each aquaria using a Mettler-Toledo Seven2Go pH /Ion meter S8, salinity was measured with a S30 SevenEasyTM conductivity meter, oxygen concentration was measured with a Fibox4 (PreSens) with a Oxygen Dipping Probe DP-PSt3.

Description: We conducted a medium-term (4 months) multiple stressor experiment with the cold-water coral Desmophyllum dianthus under future environmental conditions (IPCC RCP 8.5 scenarios for 2100), and sediment plumes generated during the potential extraction of seafloor massive sulphides. The experiment followed a two-step approach, where during the first 3 months, corals were exposed to four different treatments combining predicted scenarios of ocean acidification (pCO2/pH) and food availability. Two levels of pCO2 conditions were considered: natural habitat present day conditions (~500 µatm, 720 m depth) and IPCC RCP8.5 scenario (1000 µatm; IPCC, 2019), corresponding to pHT values of 7.93 and 7.66, respectively. In addition, two food availability regimes were recreated: high frequency of feeding (food delivered twice a day / 7 days a week) and low frequency of feeding (food delivered every other day). There were six replicate 13 L aquaria per treatment (4 D. dianthus per aquaria) at a temperature of 10.5 ± 0.1 ºC. During the fourth month of the experiment, suspended polymetallic sulphide particles generated during potential mining activities were added to half of the aquaria under the climate change scenarios at a concentration of 10 mg/l, making 8 treatments in a fully crossed experimental design for the 3 factors tested (OA, food, mining particles). Growth rates were measured using the buoyant weighing technique (Jokiel et al. 1978), using a balance (Mettler-Toledo ME204T) with a precision of 0.1 mg. Corals were weighed twice during the experiment: 1-2 weeks after the start of the experiment and just before the second phase of the experiment with PMS addition, which corresponded to a time interval of 63-71 days.

Description: We report the results of an aquaria-based experiment testing the effects of suspended particles generated during potential mining activities, on a common habitat-building coral species in the Azores, Dentomuricea aff. meteor. Coral fragments were maintained in 10-L aquaria and exposed to three experimental treatments for a period of four weeks at the DeepSeaLab aquaria facilities (Okeanos-University of the Azores): (1) control conditions (no added sediments); (2) suspended polymetallic sulphide (PMS) particles; (3) suspended quartz particles. Trace elements (Co, Cu, Mn) released from the resuspension of PMS particles to the water column in each aquaria were determined using passive sampling (DGT® Research Ltd) coupled with inductively coupled plasma mass spectrometry (ICPMS). DGT-holders were deployed in all aquaria and replaced every week (days 6, 13, 20, 27).