School of Chemical Engineering

Dr Kate O'Brien

Senior Lecturer
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

I work in interdisciplinary teams, applying a collection of modelling tools to environmental systems, evaluating drivers for change across a range of scales.  

Modelling drivers for large-scale environmental change in coastal ecosystems

Seagrass health is a key ecological indicator in coastal ecosystems, providing essential ecosystem services. My team is developing new indicators for seagrass threats associated with changes in catchment land-use and climate. We will use these new indicators in conjunction with large-scale mathematical modelling to assess how management intervention can enhance the resilience of coastal ecosystems. Student internship and PhD projects available. 

Eutrophication and sedimentation in reservoirs

Nutrient and sediment material accumulating in reservoirs represents both a loss of terrestrial soil fertility (affecting food production), and a significant threat to water supply security and flood mitigation. This study uses a combination of modelling, field work and economic analysis to determine how sediments and nutrients accumulate in tropical and sub-tropical reservoirs, and the most cost-effective way to resolve these problems. Student internship and PhD projects available. 

Challenges and opportunities in workforce diversity

Addressing wicked problems of global change and sustainable development require a diversity of approaches. Diversity in teams can improve team performance and problem solving, but there are many barriers to increasing diversity within institutions and disciplines. The purpose of this project is to mathematically model the causes and evaluate the effectives of 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.

Planetary quotas: addressing the tragedy of the commons on a global scale

The challenge of environmental change can be characterized 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 web-based 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


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


  • Juljiana Bors, PhD in progress, District Scale Assessment and Management of Residential Water and Energy Interactions
  • 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: 
  • 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.
  • 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.
  • Collier, C. J. D., M., Langlois, L. McKenzie,L. J. , C. Petus, Teixeira da Silva, E.,  McMahon, K.,, and M. P. Adams, O’Brien, K.R., Statton, J. and M. Waycott. 2014. Final report on thresholds and indicators of declining water quality as tools for tropical seagrass management. National Environmental Research Program Tropical Ecosystems Hub, final report.
  • 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
  • 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.
  • Burfeind, D.D., O'Brien, K.R. and Udy, J.W. (2013) Water temperature and benthic light levels drive horizontal expansion of Caulerpa taxifolia in native and invasive locations. Marine Ecology Progress Series, 472 : 61-72.
  • Brookes, J.D.,  O’Brien, K.R.,  Burford, M.A., Bruesewitz, D.A., Hodges, B.R. McBride, C. , and Hamilton, D.P. (2013) Effects of diurnal vertical mixing and stratification on
  • phytoplankton productivity in geothermal Lake Rotowhero, New Zealand. Inland Waters 3, 369-376.
  • Saeck, E.A., Hadwen, W.D., Rissik, D.A., O’Brien, K.R. and Burford, M.A. (2013) Flow events drive patterns of phytoplankton distribution along a river-estuary-bay continuum. Marine & Freshwater Research, in press.
  • Kehoe, M., O'Brien, K.R., Grinham, A., Rissik, D., Ahern, K. S. and Maxwell, P. (2012) Random forest algorithm yields accurate quantitative prediction models of benthic light at intertidal sites affected by toxic Lyngbya majuscula blooms. Harmful Algae, 19 : 46-52. 
  • 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.
  • 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.
  • Hamilton, D.P., O’Brien, K.R., Burford, M.A., Brookes, J.D., McBride, C.G. 2010. Vertical distributions of chlorophyll in deep, warm monomictic lakes. Aquatic Sciences 72: 295-307.
  • O’Brien, K.R., M.A. Burford and J.D Brookes. 2009. Effects of light history on primary productivity in a phytoplankton community dominated by the toxic cyanobacterium Cylindrospermopsis raciborskii. Freshwater Biology: 54 2: 272-282.
  • 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.
  • O'Brien, K.R., A.M. Waite, B.L. Alexander, K.A. Perry and L.E. Neumann. 2006. Particle-tracking in a salinity gradient: a method for measuring sinking rate of individual phytoplankton in the laboratory Limnology and Oceanography: Methods, 4:329-335.
  • O’Brien, K.R., D.L. Meyer, A.M. Waite, G.N. Ivey, and D.P. Hamilton. 2004. Disaggregation of Microcystis aeruginosa colonies under turbulent mixing: laboratory experiments in a grid-stirred tank. Hydrobiologia 519: 143-152.
  • O'Brien, K, G.N. Ivey, D.P. Hamilton, A.M. Waite and P.M. Visser. 2003. Simple criteria for the growth of negatively buoyant phytoplankton. Limnology and Oceanography 48: 1326-1337.