Marine Biophysics Unit (Satoshi Mitarai)


The Marine Biophysics Unit integrates oceanography, fluid dynamics, marine ecology, genetics, and genomics to understand how environmental changes affect past, present, and future dynamics of marine ecosystems. This information is used to promote marine conservation (coral reefs, mangroves, and deep-sea hydrothermal vents) in this era of climate change. 


Given the natural resources of Okinawa, and to make best use of academic/research resources of OIST, the Marine Biophysics Unit addresses the following questions.

1. To what extent, can we account for the biogeography of marine species, given the spatio-temporal patterns of ocean circulation in the past, present, and future?

- What impact did glacial and inter-glacial periods have on coral biodiversity?
- Are there dispersal barriers in the ocean and if so, where are they?
- Does climate change, which affects wind-driven ocean circulation, have the capacity to influence dispersal of deep-sea hydrothermal vent species?

2. How is the composition of marine species altered by brief, but powerful disturbances (e.g., typhoons) and long-term changes (e.g., global warming)?

- How does the abundance of mesoplankton community (e.g., diatoms, radiolarians, cyanobacteria, and zooplankton groups) change during a series of typhoons?
- What triggers colony formation of an alga, Phaeocystis, a globally distributed haptophyte species that forms dense blooms?
- Is red-clay runoff from sugarcane fields, often observed after intense tropical cyclones, altering the composition of marine microorganisms around Okinawan reefs?

3. Are host-symbiont dynamics (e.g., host-symbiont specificity or host mechanisms for symbiont recognition, uptake, and maintenance) being altered by environmental changes?

- What are the host-symbiont dynamics in Acantharians (major photosymbiotic protists in subtropical gyres) under different environmental conditions?
- Can we explain endosymbiotic community composition of corals by environmental conditions (e.g., temperature and light conditions), by host genotype, or both?

4. What molecular mechanisms are involved in biological responses to environmental stresses (warming/cooling, hypoxia, acidification, microplastics, etc)? 

- What molecular mechanisms explain the polyp bail-out response (besides bleaching) employed by Scleractinian corals?
- How do internal waves (upwelling of deeper water) modify coral responses to stresses?

Latest Posts

  • #JuanToRemember

    Today we mark Juan Diaz's final day as a Mitarai unit intern. After an extremely successful seven month internship studying the impact of red soil runoff on planktonic communities as a "Red-Soil Ranger" Juan will be leaving, but hopefully not for long...

  • Paleobiology of the Deep-Sea in Okinawa

    Senior scientist of Paleobiology at Sweden’s Natural History Museum in Stockholm visits OIST and the Mitarai Unit. Steffen Kiel (centre) came to hunt for fossilised deep-sea molluscs and discuss collaborations in chemosynthetic ecosystem biogeography.

  • MBU members help Onna village with typhoon relief

    OIST scientists join the cleanup effort in onna after the devestation of typhoon #24 (Trami).