Ecosystem-wide survey of the deep seafloor biome to help assess and manage the impacts of polymetallic nodule mining
The international mining community continues to develop deep-sea mining as an industry. One target area is the seafloor in the Clarion-Clipperton Zone (CCZ) of the central Pacific Ocean, which is home to polymetallic nodules. However, the environment in the CCZ is poorly explored and very little is known about what lives there.
The CCZ covers a large area – it is almost 80% of the size of the contiguous 48 states. Within this area there are large environmental differences, such as the detritus input from the surface (the food supply), and bathymetric differences, particularly many seamounts dotting the landscape. Such factors have been shown to influence the faunal communities elsewhere in the deep-sea.
Top: A map of the Clarion Clipperton Zone in the central Pacific Ocean (adapted from the International Seabed Authority, 2018). Coloured areas are those licensed for mining, and shaded squares are areas currently protected from mining.
Bottom: Seamounts across the CCZ (adapted from Wedding et al 2015).
The Smith Lab is part of an international program that is using the best available technology in deep-sea ecological, taxonomic, and connectivity studies in the western CCZ, and targeting the abyssal plain and seamounts. Data collected in this study will be used in a regional synthesis, along with data from the eastern CCZ collected recently, including the Smith lab’s ABYSSLINE project. This regional synthesis will be used to make recommendations about the environmental protection and management needed in relation to deep-sea mining.
We will address the following key questions:
1) How do biodiversity, abundance, and species composition vary for key benthic fauna across the CCZ?
2) How does ecosystem function, specifically sediment community respiration and processing of organic detritus, vary across the CCZ?
3) Are areas protected from mining similar to nearby mining claims in terms of biodiversity, species composition, and ecosystem function?
2) How do abundance, biodiversity and community structure and function vary between seamounts and the adjacent plains?
3) What is the connectivity at species and population levels between seamounts and across the western CCZ?
We are working in collaboration with lead scientists and their teams from the Natural History Museum in London, UK, Heriot Watt University in Edinburgh, UK, the University of Gothenburg, Sweden, the University of Montana, US, and Hawaii Pacific University.
International Seabed Authority: https://www.isa.org.jm/