High taxonomic diversity and miniaturization in benthic communities under persistent natural CO 2 disturbances

• Published in: Proceedings of the Royal Society B: Biological Sciences
• Main Authors: González-Delgado, Sara, Wangensteen, Owen S., Sangil, Carlos, Hernández, Celso A., Alfonso, Beatriz, Soto, Ana Z., Pérez-Portela, Rocío, Mariani, Stefano, Hernández, José Carlos
• Other Authors: Spanish government, Cabildo de La Palma, Agencia Canaria de Investigación, Innovación y Sociedad de la Información, Universidad de La Laguna, Ramón y Cajal contract, Fundación Biodiversidad
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Royal Society 2023
• Subjects: Ocean acidification
• Online Access: http://dx.doi.org/10.1098/rspb.2022.2417; https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2022.2417; https://royalsocietypublishing.org/doi/full-xml/10.1098/rspb.2022.2417

Metabarcoding techniques have revolutionized ecological research in recent years, facilitating the differentiation of cryptic species and revealing previously hidden diversity. In the current scenario of climate change and ocean acidification, biodiversity loss is one of the main threats to marine ecosystems. Here, we explored the effects of ocean acidification on marine benthic communities using DNA metabarcoding to assess the diversity of algae and metazoans. Specifically, we examined the natural pH gradient generated by the Fuencaliente CO 2 vent system, located near La Palma Island (Canary Islands). High-resolution COI metabarcoding analyses revealed high levels of taxonomic diversity in an acidified natural area for the first time. This high number of species arises from the detection of small and cryptic species that were previously undetectable by other techniques. Such species are apparently tolerant to the acidification levels expected in future oceans. Hence and following our results, future subtropical communities are expected to keep high biodiversity values under an acidification scenario, although they will tend toward overall miniaturization due to the dominance of small algal and invertebrate species, leading to changes in ecosystem functions.