Understanding the role of micronekton in the export of carbon in the Southern Ocean

Degree type

PhD

Closing date

24 September 2021

Campus

Hobart

Citizenship requirement

Domestic/International Onshore

About the research project

Carbon sequestration is the long-term storage of carbon on land and in the ocean. In the ocean, the biological gravitational pump was thought to be solely responsible for the transport of carbon from the surface waters to depth. However, it is now recognised that other processes are involved including particle injection via midwater biota. An important, yet understudied, component of this is the mesopelagic migrant pump which can lead to substantial amounts of carbon being actively transported to mesopelagic depths through the vertical migration of micronekton. Micronekton are free-swimming, taxonomically diverse, pelagic animals around 2-20 cm in size and comprise of some of the most abundant animals in the oceans. A significant part of the micronekton community undertakes daily vertical migration (DVM), where they move from the lower mesopelagic zone (400 – 1000 m) to the upper mesopelagic (200 – 400 m) and epipelagic (0 – 200 m) zones at night to feed. They then return to depth during the day. Micronekton contribute to the transport of carbon by feeding in the shallows and egesting C rich faeces in the deep. However, little is known about exactly how much carbon they transport. Models used to estimate carbon flux in the ocean typically make broadscale assumptions about micronekton community composition and behaviour, and the carbon content of different taxonomic groups. Therefore, these models may incorrectly estimate the importance of micronekton in the export of carbon in some regions. Understanding the number of individuals and the range of species undertaking DVM, as well the biogeochemistry of micronekton is an important step for understanding their role in the carbon cycle.

This project aims to contribute to international efforts of the Joint Exploration of the Twilight Zone Ocean Network (JETZON, https://www.jetzon.org/) to improve our understanding of the twilight zone by investigating the role micronekton play in sequestering carbon in the Southern Ocean. By linking ecosystem studies and biogeochemistry the successful student will use data and samples collected during the AAPP 2020/2021 SOLACE voyage to quantify carbon export by micronekton in the Southern Ocean. These data will be used as input into a carbon flux model for the Southern Ocean and overcome the shortcomings in model assumptions. Critically, this work will better link S. Ocean midwater ecology and biogeochemistry.

Primary Supervisor

Meet Prof Philip Boyd

Funding

Applicants will be considered for a Research Training Program (RTP) scholarship or Tasmania Graduate Research Scholarship (TGRS) which, if successful, provides:

  • a living allowance stipend of $28,597 per annum (2021 rate, indexed annually) for 3.5 years;
  • a relocation allowance of up to $2,000; and
  • a tuition fees offset covering the cost of tuition fees for up to four years (domestic applicants only)

If successful, international applicants will receive a University of Tasmania Fees Offset for up to four years.

As part of the application process you may indicate if you do not wish to be considered for scholarship funding.

Eligibility

The project is open to domestic (Australian and New Zealand) and international applicants who are already in Australia (onshore) at the time of submitting their application.

Due to current Australian COVID-19 travel restrictions the University cannot accept applications from international applicants who are currently overseas.

Applicants should review the Higher Degree by Research minimum entry requirements.

Selection Criteria

The project is competitively assessed and awarded.  Selection is based on academic merit and suitability to the project as determined by the College.  Applicants will be assessed and ranked according to the quality of their basis for entry research degree and institution, prior peer reviewed publications, academic awards, project-specific skills, training or relevant industry experience, referee’s reports and supervisory support.

Additional essential selection criteria specific to this project:

  • Strong biological and ecological background
  • Strong biogeochemistry background
  • Strong analytical skills, especially with scientific analysis/programming software
  • Strong English written and oral communications

Additional desirable selection criteria specific to this project:

  • Experience with microscopy
  • Experience with zooplankton/micronekton identification
  • Experience in ecosystem modelling
  • Experience in laboratory analysis

Application process

There is a three-step application process:

  1. Select the project, and check you meet the eligibility and selection criteria;
  2. Contact the Primary Supervisor, Prof Philip Boyd, if you have any questions about the project; and
  3. Click here to submit an application by the closing date listed above.
    • Copy and paste the title of the project from this advertisement into your application. If you don’t correctly do this your application may be rejected.
    • As part of your application you will be required to submit a covering letter, a CV including 2 x referees and your project research proposal.

Following the application closing date applications will be assessed within the College. Applicants should expect to receive notification of the outcome by email.

Apply now Explore other projects

Why the University of Tasmania?

Worldwide reputation for research excellence

Quality supervision and support

Tasmania offers a unique study lifestyle experience