Deep-sea biodiversity at the extremes of the Salas y Gómez and Nazca ridges with implications for conservation

pseudo-F1,43 = 5.456, p < 0.001) but not between habitats (PERMANOVA pseudo-F1,43 = 1.524, p = 0.188) or their interaction (PERMANOVA pseudo-F1,43 = 0.699, p = 0.552). PC1 accounted for 48.1% of the variation in environmental variables, with the major loadings being silicate (-0.349), nitrate (-0.342), phosphate (-0.340), apparent oxygen utilization (-0.340), and depth (-0.335). PC2 accounted for an additional 17.8% of the variation in environmental variables, with the major loadings being crust age (-0.504), chlorophyll-a (-0.503), number of seamounts within 30 km pf the sample sites (0.358), and dissolved O2 (0.329). Nitrate, phosphate, silicate, salinity, and depth were all highly correlated with one another and inversely related to tempera- ture. Subregions separated out along PC2 with sites at Desventuradas being older geologically with higher chlorophyll-a. Deployments at RN/SyG had more seamounts within 30 km of the sample sites and higher measures of habitat complexity (BPI) at both fine and broad scales. Invertebrate assemblages There were 56 invertebrate taxa from 5 phyla, 12 classes, 13 orders, and 22 infra-orders or fam- ilies identified on camera deployments (S2 Table). There were no significant differences in the Fig 4. Principal Components Analysis (PCA) of environmental variables at camera deployment sites. Data were Box-Cox transformed prior to analysis. Des. = Desventuradas. https://doi.org/10.1371/journal.pone.0253213.g004 PLOS ONE Deep-sea biodiversity along the Salas y Go´ mez and Nazca ridges

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