The Clarion Clipperton Zone (CCZ) in the equatorial Pacific Ocean is a vast region of abyssal plains and hills, polymetallic nodule fields, and seamounts. Because of the cobalt, nickel and copper content of polymetallic nodules in this region, the CCZ is targeted for deep-seabed mining. In order to safeguard seafloor biodiversity and ecosystem functions across the region in the event of mining, the International Seabed Authority (ISA) in 2012 designated nine 400×400 km no-mining areas, called Areas of Particular Environmental Interest (APEIs) (Wedding et al., 2013). The APEIs were designed based on environmental correlates of biodiversity and ecosystem function to be representative of the full range of seafloor habitats and communities potentially impacted by nodule-mining activities within the licensed mining exploration areas spanning the CCZ (Wedding et al., 2013). Since APEI establishment in 2012, a substantial number of research expeditions have collected biodiversity and ecosystem-function data within the CCZ. These expeditions mainly focused on individual contract areas or APEIs. To date, there have been limited efforts to synthesize data at the regional level, which is critical for the further development of ISA’s CCZ Environmental Management Plan (EMP). The Deep CCZ Biodiversity Synthesis Workshop was conducted in October 2019 with a new focus on the CCZ EMP, specifically to (1) compile recent deep-sea ecosystem data from across the CCZ, (2) synthesize patterns of seafloor biodiversity, ecosystem functions, and potential environmental drivers, and (3) assess the representativity of the APEIs for areas in the CCZ targeted for polymetallic nodule mining (International Seabed Authority, 2020). This Special Research Topic of Frontiers in Marine Science draws together scientific papers derived from the workshop, as well as others elucidating environmental variability and deep-sea biodiversity across the region.



Publication Date


Publication Title

Frontiers in Marine Science



Embargo Period


Organisational Unit

School of Biological and Marine Sciences