The Deep Ocean

What are the community structures and the biogeochemical characteristics of deep and abyssal waters in the eastern South Pacific?

The ecosystems in deep eastern South Pacific (ESP) waters are almost unknown. That is why the exploration of mesopelagic (>500 m) and abyssopelagic (>3000 m) communities represents a unique opportunity for science to discover new lifeforms, species, and genes, while also posing a major challenge for oceanography in the South Pacific Basin.

At the Millennium Institute of Oceanography we have decided to take on this challenge, and our project will allow us to reveal the mechanisms through which communities spread widely, colonizing unique habitats such as the Atacama Trench and the Nazca, Salas & Gómez, and Juan Fernández ridges. Our hypothesis is that these ranges significantly contribute to the dispersion of species and the gene flow in the coast-ocean direction, produced by the circulation of water masses and the water mixture associated with meso and large-scale physical dynamics.

To test our hypothesis we will collect deep water samples by means of a MOCNESS net (maximum depth: 6,500m) with an underwater video profiler (UVP), conductivity, temperature and fluorescence sensors, and stratified sampling nets. The UVP will provide particle-size distribution profiles, while the net samples will be divided for examination of live animals, DNA analysis and taxonomic studies. Water samples for molecular and genomic analyses of microbial communities (ranging from viruses to protists) will also be taken and in-situ incubation systems will be developed to calculate activity/ (micro) biological rates. We will also undertake quantitative and qualitative assessments of fish parasites and plankton as biomarkers for parasite host dispersion and habitat colonization.  Individual and biogeochemical models will be used to analyze the mechanisms that contribute to preserving endemic communities and the connectivity among different islands, seamounts and other oceanic regions.

The expeditions will be organized in cooperation with international partners. The molecular analyses of selected plankton will focus on DNA microsatellites and mitochondrial DNA in order to relate sampled populations and species both in the coast-ocean direction and in the vertical dimension. Additionally, the biogeochemical conditions of the deep ocean will be defined through measurements of carbon and pH/pCO2 reserves, along with saturation states of calcite and aragonite (Ω). We will also perform measurements of inorganic carbon isotopes (12C, 13C, and 14C) and dissolved organic carbon as well as age determination (DO14C) to learn about biogeochemical rates and the mixture of water masses in deep water ecosystems.



Meet our researchers


A new species of Proctoeces and reinstatement of Proctoeces humboldti George-Nascimento and Quiroga 1983 (Digenea: Fellodistomidae) based on molecular and morphological evidence

Parasitology International | Volume 67, Issue 2, Pages 159-169

doi:10.1016/j.parint.2017.10.004April, 2018

Oliva, M.E.Valdivia, I.M.Cárdenas, L.Muñoz, G.Escribano, R.George-Nascimento, M.

Dissolved compounds excreted by copepods reshape the active marine bacterioplankton community composition

Frontiers in Marine Science | Volume 4, Issue 343, Pages 1-22

doi:10.3389/fmars.2017.00343November, 2017

Valdés, V.Fernandez, C.Molina, V.Escribano, R.Joux, F.

Embryo and early larval stages of the Humboldt Current krill Euphausia mucronata (Crustacea: Euphausiacea)

Invertebrate Biology | Volume 136, Issue 3, Pages 260-270

doi:10.1111/ivb.12176September, 2017

Riquelme-Bugueño, R.Gómez-Gutiérrez, J.Silva-Aburto, J.Escribano, R.Schneider, W.

Nitrogen excretion by copepods and its effect on ammonia-oxidizing communities in a coastal upwelling zone

Limnology and Oceanography

doi:10.1002/lno.10629July, 2017

Valdés, V.Fernández, C.Molina, V.Escribano, R.

Zooplankton community response to the winter 2013 deep convection process in the NW Mediterranean Sea

Journal of Geophysical Research: Oceans | Volume 122, Issue 3, Pages 2319-2338

doi:10.1002/2016JC012176March, 2017

Donoso, K.Carlotti, F.Pagano, M.Hunt, B.P.V.Escribano, R.Berline, L.

Acanthocotyle gurgesiella n. sp. (Monogenea: Acanthocotylidae) from the deep-sea skate Gurgesiella furvescens (Rajidae) in the south-eastern Pacific

Journal of Helminthology | Pages 1-5

doi:10.1017/S0022149X17000220March, 2017

A review of the parasites infecting fishes of the genus Trachurus (Pisces: Carangidae)

Reviews in Fisheries Science & Aquaculture | Volume 25, Issue 4, Pages 297-315

doi:10.1080/23308249.2017.1293607March, 2017

Costa, G.MacKenzie, K.Oliva, M.E.

Scaling copepod grazing in a coastal upwelling system: The importance of community size structure for phytoplankton C flux

Latin American Journal of Aquatic Research | Volume 45, Issue 1, Pages 41-54

doi:10.3856/vol45-issue1-fulltext-5March, 2017

Other research lines

Universidad de ConcepciónPontificia Universidad Católica de ChileMinisterio de Economía, Fomento y TurismoIniciativa Científica Milenio
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