Impact of ferromanganese ore pollution on phytoplankton CO2 fixation in the surface ocean. (September 2019)

• Record Type: Journal Article
• Authors: Dabrowska, Alicja; Kamennaya, Nina A.; Murton, Bramley J.; Zubkov, Mikhail V.
• Is Part Of: Marine pollution bulletin. Volume 146(2019)
• Page Start: 1002
• Page End: 1006
• Publication Date: 2019-09
• Subjects: Ferromanganese polymetallic crust -- Deep-sea mining -- Oceanic phytoplankton -- Primary production; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2019.07.062
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: Because ferromanganese polymetallic crusts can become a global resource of valuable elements the ecological impact of seafloor crust mining requires evaluation. Whilst the detrimental impact on deep-ocean benthos is established, experimental evidence about the mining hazard to surface-ocean is sparse. When retrieved, mined crusts can leach elements potentially harmfull to the core oceanic CO2 -fixers – phytoplankton. To directly assess the magnitude of this potential hazard at ocean-basin scale, we examine the impact of ore slurry on phytoplankton CO2 fixation along a meridional transect through the South Atlantic Ocean. Within 12 h crust slurry additions caused a 25% decrease of CO2 fixation in the subtropical region and 15% in the temperate-polar region. Such moderate susceptibility of phytoplankton indicates limited release of harmful elements from tested polymetallic powder. Although this implies that environmentally sustainable seafloor mining could be feasible, longer-term complex studies of the mining impact on the surface ocean are required. Highlights: Slurry of mined deep-ocean crust can inhibit CO2 fixation at the ocean surface. Addition of nutrient-rich deep water to the slurry does not alleviate the inhibition. CO2 -fixers of nutrient-poor tropical ocean are most susceptible to the slurry. Blooming phytoplankton is least susceptible to the slurry. The impact of the slurry on CO2 fixation within 12 h is moderate.