@article{fdi:010088941,
  title = {{M}ultiscale spatial patterns and environmental drivers of seamount and island slope megafaunal assemblages along the {M}ozambique channel},
  author = {{H}anafi-{P}ortier, {M}. and {S}amadi, {S}arah and {C}orbari, {L}. and {B}oulard, {M}. and {M}iramontes, {E}. and {P}enven, {P}ierrick and {L}eroy, {B}. and {N}apol{\'e}on, {T}. and {J}orry, {S}. {J}. and {O}lu, {K}.},
  editor = {},
  language = {{ENG}},
  abstract = {{S}eamounts are vulnerable ecosystems targeted by fishing and potentially by future mineral exploitation. {T}heir abundance, widespread distribution, and heterogeneity of faunal and abiotic components require integrated studies at multiscale to describe spatial patterns and identify environmental drivers needed by conservation plans. {T}here is also a lack of knowledge on seamount benthic ecosystems in some regions, such as the {I}ndian {O}cean. {T}hese gaps, in the context of {M}arine {P}rotected {A}reas establishment in the region, have motivated the present study focusing on the {M}ozambique {C}hannel {E}parses islands and flat top seamounts, along a 10-degree latitude gradient. {T}hese structures are characterized by complex volcanic and carbonate geomorphologies at multiscale and are distributed along a highly dynamic turbulent ocean circulation area with large anticyclonic eddies. {F}or the first time, we analysed, from seabed image transects obtained by towed-camera on four seamounts, and two volcanic islands - {B}assas da {I}ndia and {M}ayotte - external slopes, and from multiscale environmental data, how benthic communities respond to this high habitat heterogeneity at regional, and local scales. {T}his study reveals high discrepancies of benthic megafauna richness, density, and beta diversity among seamounts and among slopes of the same islands. {M}oreover, at similar latitude, seamounts display higher densities than island slopes. {T}he highest densities found on a seamount of the {G}lorieuses archipelago are explained by strong currents and flat homogeneous geomorphology. {E}xcept on this seamount, the beta diversity is high, despite the quite limited depth range explored (84-734 m) and is the highest on island slopes and {H}all {B}ank, driven by the diversity and hardness of the substrate. {B}eta diversity is mainly due to taxa turnover, with high contribution of the habitat-forming sponges and cnidarians, together with a few mobile taxa. {W}e identified from biogeographic network analysis 12 dominant faunal assemblages, displaying a patchy distribution, with variability in composition both among and within sites. {C}urrents and primary productivity explain similar to 15% of the observed assemblage structure along the channel, while geomorphology (km scale), topography (60-500 m scale) and substrate (60-m units) explain together 24% of the faunal spatial patterns. {A}nalysis of spatial structures along island slopes detected some small (100-200 m), medium (similar to 1 km) and large scale (similar to 2-6 km) megabenthic community structures, partly explained by topography, substrate, depth, and slope. {D}espite limited taxonomic identifications for this poorly sampled area, this study reveals an outstanding heterogeneity of megabenthic assemblages at multispatial scales in the {M}ozambique {C}hannel seamounts and island slopes, in response to the complex hydrography and geology of the area. {F}urther characterization of environmental drivers with greater focus at local scales including hydrographic variables are therefore needed to improve predictions of suitable habitats of vulnerable marine ecosystems.},
  keywords = {{S}eamounts & island slopes ; {B}athyal megabenthic assemblages ; {B}eta-diversity ; {M}ultiscale abiotic factors ; {S}patial & image analyses ; {M}ozambique channel ; {OCEAN} {INDIEN} ; {MOZAMBIQUE} {CANAL}},
  booktitle = {},
  journal = {{D}eep-{S}ea {R}esearch {P}art {I} : {O}ceanographic {R}esearch {P}apers},
  volume = {203},
  numero = {},
  pages = {104198 [23 p.]},
  ISSN = {0967-0637},
  year = {2024},
  DOI = {10.1016/j.dsr.2023.104198},
  URL = {https://www.documentation.ird.fr/hor/fdi:010088941},
}