School of Chemical Engineering

Associate Professor Kate O'Brien

Associate Professor
Office: 74-332
Phone: +61 7 3365 3534


  • 2003 PhD The University of Western Australia  The effects of turbulent mixing on the vertical distribution of phytoplankton populations”  Supervisors Greg Ivey, David Hamilton, Anya Waite
  • 1994 Bachelor of Chemical Engineering, Honours I, The University of Queensland, Australia
  • 1994 Bachelor of Science (Mathematics) The University of Queensland, Australia



Environmental systems modelling and analysis

Sustainable management of ecosystems is a critical issue facing humanity. Unprecedented changes to ecosystems over the past half century have simultaneously improved the quality of life for billions of people, and undermined the ability of ecosystems to provide the services on which human survival and development depend, such as provision of food, fresh water, fibre and energy. The result has been the costly degradation of many ecosystems. I work in interdisciplinary teams, applying a collection of modelling tools across a range of scales to address the question, how can we manage our natural resources more sustainably? There are three core themes in my research:

Modelling drivers for environmental change in aquatic ecosystems

Our society depends on the health of our aquatic ecosystems in many ways: as sources of freshwater and food, venue of valuable economic, social and leisure activities, flood mitigation and climate moderation. However the health of our aquatic ecosystems is under threat from land-use modification, urbanisation, coastal development and climate change. My team applies a range of modelling and analysis methods to assess how external threats affect aquatic ecosystem health, and what can be done to mitigate or avoid ecosystem damage. Specific projects include value and vulnerability of seagrass habitat, and impact of eutrophication on water supplies. Student internship and PhD projects available.

Challenges and opportunities in workforce diversity

Tackling the wicked problems of global change and sustainable development will mean using our human capital in new ways. Diversity in teams can increase the range of perspectives available, enhancing creativity and problem solving. However there are many barriers to increasing diversity within institutions and disciplines. The purpose of this project is to investigate the causes and potential solutions to low workforce diversity in science and engineering, using a combination of mathematical model and data collection. The results will be applied more broadly, to identify barriers and solutions to creating diverse teams in different fields worldwide. Student internship and PhD projects available.

Applied projects tackling climate change

The challenge of environmental change can be characterised as the “tragedy of the commons”: whereby we benefit individually and immediately from actions which lead to long-term consequences shared across a wider population and over time. Many studies have quantified footprint of individuals, organisations and nations in various forms, and concluded that globally we are living beyond our means. However individuals lack quantitative information needed to make informed decisions and personal trade-offs which lead to genuinely sustainable consumption. This project aims to develop tools which will enable individuals to make informed choices about how they can consume a sustainable share of the world's resources, and so directly address the tragedy of the commons. Student internship and PhD projects available.

Teaching and Learning: 

2011- present BE/ME chemical-environmental program leader

2012 - present Developed and co-ordinated Introduction to environmental systems engineering CHEE2501

2006-present Lecturer and course coordinator in Heat and mass transfer CHEE3002

2003-2008 Lecturer in Engineering analysis of environmental systems in Introduction to Professional Engineering ENGG1000

Teaching awards: Nominated for UQ Excellence in Teaching Award 2010-2012, Awarded EAIT Faculty Excellence in Teaching Award 2009, Awarded School of Engineering Excellence in Teaching Award 2008, received more than 30 Dean’s Commendations for effective teaching 2006 to present.





Project title

Granting Agency

Chief Investigators

2013 - 2016

Annual audit of GHG emissions associated with staff and student commuting to UQ St Lucia campus

UQ Properties and Facilities

O’Brien, Lambert


Modelling Small Scale Ecological Processes in Estuarine  Environments

NSW OEH (Office of Environment and Heritage)

O’Brien, Adams, Ferguson


Impacts of local, regional and global environmental change on coastal ecosystem health using the eReefs coupled hydrodynamic-biogeochemical model.


O’Brien, Baird, Adams


Seagrass growth and diversity: attributes of a resilient GBR (Phase II)


Great Barrier Reef Foundation

Collier, van Dijk, Adams, O’Brien, Waycott, McKenzie, Uthicke, Phinn, Roelfsema


Seagrass connectivity, community composition and growth: attributes of a resilient Great Barrier Reef (Phase I)

Great Barrier Reef Foundation

Collier, van Dijk, O’Brien, Waycott, McKenzie, Uthicke, Liddy, Phinn


Assessment of carbon partitioning and storage in seagrass ecosystems using mathematical models validated across multiple latitudes and species

UWA-UQ Bilateral Research Collaboration Award (BRCA) Scheme

O’Brien, Kendrick, Adams, Hovey, Hipsey, Bruce, Lowe


Modelling resilience and critical thresholds in seagrass systems

EAIT strategic grant



Seagrass as an ecological indicator: resolving challenges of scale and complexity

UQ Collaboration and Industry Engagement Fund

O’Brien, Mumby, Callaghan, Roelfsema, Grinham


Sources of phosphorus promoting cyanobacteria in subtropical reservoirs

ARC linkage

Burford, O’Brien, Hamilton, Lemckert


  • Saphira Rekker, PhD in progress: A planetary limits approach to measuring corporate environmental sustainability
  • Alice Twomey, PhD in progress: Quantifying ecosystem services associated with seagrass below-ground biomass
  • Juljiana Bors, PhD in progress: District Scale Assessment and Management of Residential Water and Energy Interactions
  • Man Xiao, PhD in progress: Investigating the effects of physical factors on competition between Cylindrospermopsis raciborskii and Microcystis aeruginosa
  • Amanda Nielen, PhD in progress: Sources, transformations and fate of catchment-derived dissolved organic matter
  • Matthew Prentice, PhD in progress: The role of phosphorus in promoting cyanobacteria blooms in subtropical reservoirs
  • Emily Saeck, PhD 2012, Nutrient dynamics of coastal phytoplankton: the role of episodic flow events and chronic sewage discharges
  • Michael Kehoe, PhD 2010, Modelling of physical and physiological processes controlling primary production and growth in cyanobacteria
  • Dana Burfeind, PhD 2009, Caulerpa taxifolia growth dynamics in invasive and native populations
Key Publications: 

Drivers for change in aquatic ecosystems:

  • Adams, M. P., M. I. Saunders, P. S. Maxwell, D. Tuazon, C. M. Roelfsema, D. P. Callaghan, J. Leon, A. R. Grinham, and K. R. O'Brien. 2015. Prioritizing localized management actions for seagrass conservation and restoration using a species distribution model. Aquatic Conservation: marine and freshwater ecosystems.
  • Collier C, Adams M, Langlois L, Waycott M, O'Brien K, Maxwell P, McKenzie L. 2016. Thresholds for morphological response to light reduction for four tropical seagrass species. Ecological Indicators 67: 358-366
  • Burford M, Valdez D, Curwen G, Faggotter S, Ward D, O’Brien KR. 2016. Inundation of saline supratidal mudflats provides an important source of carbon and nutrients in an aquatic system. Marine Ecology Progress Series 545: 21-33.
  • Saunders, M.I., Leon, J.P., Phinn, S.R., Callaghan, D.P.,O’Brien, K.R., Roelfsema, C.M., Lovelock, C. E., Lyons, M.B. and Mumby, P. J. (2013) Coastal retreat and improved water quality mitigate losses of seagrass from sea level rise. Global Change Biology, in press
  • van Katwijk MM, Thorhaug A, Marbà N, Orth RJ, Duarte CM, Kendrick GA, Althuizen IHJ, Balestri E, Bernard G, Cambridge ML, Cunha A, Durance C, Giesen W, Han Q, Hosokawa S, Kiswara W, Komatsu T, Lardicci C, Lee KS, Meinesz A, Nakaoka M, O'Brien KR, Paling EI, Pickerell C, Ransijn AMA, JJ V. 2016. Global review of seagrass restoration and the importance of large-scale planting. Journal of Applied Ecology 53.
  • Kilminster, K., K. McMahon, M. Waycott, G. A. Kendrick, P. Scanes, L. McKenzie, K. R. O'Brien, M. Lyons, A. Ferguson, and P. Maxwell. 2015. Unravelling complexity in seagrass systems for management: Australia as a microcosm. Science of The Total Environment.
  • Vonk, J. A., M. J. Christianen, J. Stapel, and K. R. O’Brien. 2015. What lies beneath: Why knowledge of belowground biomass dynamics is crucial to effective seagrass management. Ecological Indicators 57:259-267.
  • Saeck , E.A., O’Brien, K.R., Weber, T.R and Burford M.A. (2013) Changes to chronic nitrogen loading from sewage discharges modify standing stocks of coastal phytoplankton.  Marine Pollution Bulletin, in press.
  • Adams, M. P., R. K. Hovey, M. R. Hipsey, L. C. Bruce, M. Ghisalberti, R. J. Lowe, R. K. Gruber, L. Ruiz-Montoya, P. S. Maxwell, D. P. Callaghan, G. A. Kendrick, and K. R. O'Brien. 2016. Feedback between sediment and light for seagrass: Where is it important? Limnology and Oceanography
  • Burford, M.A., Green, S.A., Cook, A.J., Johnson, S.A., Kerr, J.G., O’Brien, K.R. 2012. Sources and fate of nutrients in a subtropical reservoir. Aquatic Sciences, 74 1: 179-190.

Challenges and opportunities in workforce diversity

  • O’Brien, K. R., M. Scheffer, E. H. van Nes, and R. van der Lee (2015), How to Break the Cycle of Low Workforce Diversity: A Model for Change, PloS one, 10(7).
  • O'Brien, K.R., Hapgood, K.P. 2012 The academic jungle: Ecosystem modelling reveals why women are driven out of research. Oikos, 121 7: 999-1004.
  • O'Brien, K., Hapgood, K. 2011 Part-time balance. Nature, 479 : 257-258.

Applied projects tackling climate change

  • Lam K, Lant P, O'Brien K, Kenway S. 2016. Comparison of water-energy trajectories of two major regions experiencing water shortage. Journal of Environmental Management 181: 403-412.
  • O’Brien, K.R., J. Menache, L.M. O’Moore 2009 Impact of fly ash content and fly ash transportation distance on embodied greenhouse gas emissions and water consumption in concrete. Int. J. Life Cycle Assessment, 14: 621-629.