Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Journal topic
Discussion papers
https://doi.org/10.5194/bg-2019-360
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-2019-360
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Submitted as: research article 26 Nov 2019

Submitted as: research article | 26 Nov 2019

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Biogeosciences (BG).

Unexpected high abyssal ophiuroid diversity in polymetallic nodule fields of the Northeast Pacific Ocean, and implications for conservation

Magdalini Christodoulou1, Timothy O'Hara2, Andrew Hugall2, Sahar Khodami1, Clara F. Rodrigues3, Ana Hilario3, Annemiek Vink4, and Pedro Martinez Arbizu1 Magdalini Christodoulou et al.
  • 1German Centre for Marine Biodiversity Research (DZMB), Senckenberg am Meer, Wilhelmshaven, 26382, Germany
  • 2Laboratory example, city, postal code, country Museums Victoria, Melbourne, 3001, Australia
  • 3Departamento de Biologia and CESAM, Universidade de Aveiro, Aveiro, 3810–193, Portugal
  • 4Federal Institute for Geosciences and Natural Resources, Marine Geology, 30655, Hannover, Germany

Abstract. The largest and commercially appealing mineral deposits can be found in the abyssal seafloor of the Clarion-Clipperton Zone (CCZ), a polymetallic nodule province, in the NE Pacific Ocean, where experimental mining is due to take place. In anticipation of deep-sea mining impacts, it has become essential to rapidly and accurately assess biodiversity. For this reason, ophiuroid material collected during seven scientific cruises from five exploration license areas within CCZ, one area protected from mining (APEI3, Area of Particular Environmental Interest) in the periphery of CCZ and the DIS-turbance and re-COLonisation (DISCOL) Experimental Area (DEA), in the SE Pacific Ocean, was examined. Specimens were genetically analysed using a fragment of the mitochondrial cytochrome c oxidase subunit I (COI). Maximum Likelihood and Neighbour Joining trees were constructed, while four tree-based and distance-based methods of species delineation (ABGD, BINs, GMYC, mPTP) were employed to propose Secondary Species Hypotheses (SSHs) within the ophiuroids collected. The species delimitations analyses concordant results revealed the presence of 43 deep-sea brittle stars SSHs, revealing an unexpectedly high diversity and showing that the most conspicuous invertebrates in abyssal plains have been so far considerably under-estimated. The number of SSHs found in each area varied from 5 (IFREMER area) to 24 (BGR area), while 13 SSHs were represented by singletons. None of the SSHs was found to be present in all 7 areas, while the majority of species (44.2 %) had a single-area presence (19 SSHs). The most common species were Ophioleucidae sp. (Species 29), Amphioplus daleus (Species 2) and Ophiosphalma glabrum (Species 3), present in all areas except APEI3. The biodiversity patterns could be mainly attributed to POC fluxes that could explain the highest species numbers found in BGR (German contractor area) and UKSRL (UK contractor area) areas. The five exploration contract areas belong to a mesotrophic province, while in contrary the APEI3 is located in an oligotrophic province which could explain the lowest diversity as well as very low similarity with the other six study areas. Based on these results the representativeness and the appropriateness of APEI3 to meet its purpose of preserving the biodiversity of the CCZ fauna are questioned. Finally, this study provides the foundation for biogeographic and functional analyses that will provide insight into the drivers of species diversity and its role in ecosystem function.

Magdalini Christodoulou et al.
Interactive discussion
Status: open (until 07 Jan 2020)
Status: open (until 07 Jan 2020)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Magdalini Christodoulou et al.
Magdalini Christodoulou et al.
Viewed  
Total article views: 143 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
122 21 0 143 13 0 1
  • HTML: 122
  • PDF: 21
  • XML: 0
  • Total: 143
  • Supplement: 13
  • BibTeX: 0
  • EndNote: 1
Views and downloads (calculated since 26 Nov 2019)
Cumulative views and downloads (calculated since 26 Nov 2019)
Viewed (geographical distribution)  
Total article views: 120 (including HTML, PDF, and XML) Thereof 119 with geography defined and 1 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 12 Dec 2019
Publications Copernicus
Download
Short summary
Unexpectedly high ophiuroid diversity is revealed, showing that the most conspicuous invertebrates in abyssal plains have been considerably underestimated. The ophiuroid biodiversity patterns observed in a potential mining area (CCZ) could be mainly attributed to differences in particulate organic carbon (POC) fluxes. The protected area's (APEI-3) purpose of preserving the biodiversity of the CCZ fauna is questioned, while the creation of no-mining sites within the core CCZ area is suggested.
Unexpectedly high ophiuroid diversity is revealed, showing that the most conspicuous...
Citation