ORCID
- Kerry L. Howell: 0000-0003-3359-1778
Abstract
AimLatitudinal and bathymetric species diversity gradients in the deep sea have been identified, but studies have rarely considered these gradients across hard substratum habitats, such as seamount and oceanic island margins. This study aimed to identify whether the current understanding of latitudinal and bathymetric gradients in α-diversity (species richness) apply to seamount ecosystems, as well as ascertaining whether identifiable trends were present in seamount β-diversity along a bathymetric gradient.LocationExclusive Economic Zones of Saint Helena, Ascension Island and Tristan da Cunha, spanning 8–40°S in the South Atlantic.TaxonSeamount megabenthic communities.MethodsImages from 39 transects, collected between 250 and 950 m, were used to characterise species richness. We subsequently applied general linear models to test possible environmental drivers across latitudinal and bathymetric ranges. Regression models were employed to investigate the β-diversity gradient of species turnover with depth.ResultsTransects in temperate latitude had significantly higher species richness than those in the tropics. Surface primary productivity and substrate hardness both had significant positive effects on species richness, and a weak relationship between temperature and species richness was observed. No significant relationship between species richness and depth was detected, but there was significant species turnover with depth.Main conclusionsSeamounts and oceanic islands do not conform to established depth–diversity relationships within the depth range studied. However, seamounts and oceanic islands in the South Atlantic do appear to follow a parabolic latitudinal diversity gradient, closely associated with higher productivity in temperate regions.
DOI Link
Publication Date
2022-01-01
Publication Title
Journal of Biogeography
Volume
49
Issue
5
ISSN
0305-0270
Acceptance Date
2022-02-16
Deposit Date
2022-04-28
Embargo Period
2022-04-29
Funding
British Antarctic Survey Centre for Environment, Fisheries and Aquaculture Science Foreign and Commonwealth Office Plymouth University
Keywords
deep-sea ecology, diversity gradient, South Atlantic, spatial ecology
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
First Page
904
Last Page
915
Recommended Citation
Bridges, A., Barnes, D., Bell, J., Ross, R., & Howell, K. (2022) 'Depth and latitudinal gradients of diversity in seamount benthic communities', Journal of Biogeography, 49(5), pp. 904-915. Available at: 10.1111/jbi.14355
