Philip Orr

Adjunct Senior Research Fellow, Australian Rivers Institute, Griffith University, Nathan

Ph.D.  University of Technology, Sydney

Contact details:

Telephone:+61 7 3735 5190+61 7 3735 5190



SCOPUS Author ID:7006077256

I am a trained plant physiologist/biochemist and in the early part of my career worked on physiology (growth primary production and ecophysiology) of submerged, emergent and floating aquatic plants.  I later turned my research to cyanobacteria (blue-green algae) where I have studied the relationship between water chemistry/reservoir dynamics and blue-green algae blooms, their toxins and their management.

I continue to actively undertake research on cyanobacteria and their toxins.  I also provide advice on implementing the cyanobacterial component of the Australian Drinking Water Guidelines, the Guidelines for Managing Risks in Recreational Waters and the Australian and New Zealand Water Quality Guidelines.

Research Areas

·        Physiology, toxicology and management of toxic cyanobacteria and their toxins

·        Primary production and ecophysiology of submerged, emergent and floating aquatic plants

·        Limnology, water quality and water treatment processes

Research Interests

·        Factors controlling toxin production by toxic cyanobacteria

·        Novel methods to detect toxic cyanobacteria in mixed populations

·        Impacts of global climate change on primary production of aquatic plants, algae and cyanobacteria

·        Water treatment processes

·        Relationship between measure water quality parameters and the public perception of water quality


Thesis - Doctor of Philosophy - 2006

1.       “Cyanobacteria in Australia – Management of blooms and toxins” University of Technology Sydney.

Papers – Refereed Journals (33)

2.       Denny, P., ORR, P.T. and Erskine, D.J.C. (1983).  Potentiometric measurements of carbon dioxide flux of submerged aquatic macrophytes in pH-statted natural waters. Freshwater Biology13 507-519.

DOI: 10.1111/j.1365-2427.1983.tb00010.x

3.       Sale P.J.M., ORR, P.T., Shell, G.S. and Erskine, D.J.C. (1985).  Photosynthesis and growth rates in Salvinia molesta and Eichhornia crassipes. Journal of Applied Ecology22 125-137.

DOI: 10.2307/2403332

4.       Sale P.J.M. and ORR, P.T. (1986).  Gas Exchange of Typha orientalis Presl communities in artificial ponds. Aquatic Botany23 329-339.

DOI: 10.1016/0304-3770(86)90081-1

5.       Sale, P.J.M. and ORR, P.T. (1987).  Growth Responses of Typha orientalis Presl to controlled temperatures and photoperiods. Aquatic Botany29 227-243.

DOI: 10.1016/0304-3770(87)90018-0

6.       ORR, P.T., Pokorný, J, Denny, P. and Sale, P.M.J. (1988).  Photosynthetic response of Myriophyllum salsugineum A.E. Orchard to photon irradiance, temperature and external free-CO 2. Aquatic Botany30 363-378.

DOI: 10.1016/0304-3770(88)90068-X

7.       Pokorný, J., ORR, P.T., Ondok, J.P. and Denny, P. (1989).  Photosynthetic quotients of some aquatic macrophyte species. Photosynthetica23(4) 494-506.

(Not currently available on line)

8.       Brix, H., Sorrell, B.K. and ORR, P.T. (1992).  Internal pressurisation and convective gas flow in some emergent freshwater macrophytes. Limnology and Oceanography37(7) 1420-1433.

DOI: 10.4319/lo.1992.37.7.1420

9.       Sorrell, B.K., Brix, H. and ORR, P.T. (1993).  Oxygen exchange by entire root systems of Cyperus involucratus and Eleocharis sphacelata.  Journal of Aquatic Plant Management31 24-28.

10.     Sorrell, B.K. and ORR, P.T. (1993).  H + exchange and nutrient uptake by roots of the emergent hydrophytes, Cyperus involucratus Rottb., Eleocharis sphacelata R. Br. and Juncus ingens N. A. Wakef.  New Phytologist 125 85-92.

DOI: 10.1111/j.1469-8137.1993.tb03866.x

11.     Jones G.J. and ORR, P.T. (1994).  Release and degradation of microcystin following algicide treatment of a Microcystis aeruginosa bloom in a recreational lake, as determined by HPLC and protein phosphatase inhibition assay.  Water Research28(4) 871-876.

DOI: 10.1016/0043-1354(94)90093-0

12.     Bolch, C.J.S., Blackburn, S.I., Jones, G.J., ORR, P.T. and Grewe, P.M. (1997).  Plasmid content and distribution in the toxic cyanobacterial genus Microcystis Kützing ex Lemmermann (Cyanobacteria: Chroococcales).  Phycologia36(1) 6-11.

DOI: 10.2216/i0031-8884-36-1-6.1

13.     Sorrell, B.K., Brix, H., ORR, P.T.  (1997).  Eleocharis sphacelata: Internal gas transport pathways and modelling of aeration by pressurized flow and diffusion. New Phytologist136(3) 433-442.

DOI: 10.1046/j.1469-8137.1997.00769.x

14.     ORR, P.T. and Jones, G.J. (1998).  Relationship between microcystin production and cell division rates in nitrogen-limited Microcystis aeruginosa cultures. Limnology and Oceanography  43(7) 1604-1614.

DOI: 10.4319/lo.1998.43.7.1604

15.     Feitz, A.J., Waite, D., Jones, G.J., Boyden, B.H. and ORR, P.T. (1999).  Photocatalytic degradation of the blue-green algal toxin microcystin-LR in a natural organic-aqueous mix.  Environmental Science and Technology33(2) 243-249.

DOI: 10.1021/es970952d

16.     Bolch, C.J.S., ORR P.T., Jones, G.J. and Blackburn, S.I. (1999).  Genetic, morphological, and toxicological variation among globally distributed strains of Nodularia (cyanobacteria). Journal of Phycology35(2) 339-355.

DOI: 10.1046/j.1529-8817.1999.3520339.x

17.     McSweeney, C.S., Conlan, L.L., Hegarty, M., Krause, D.O., Gough, J. and ORR P. (2000).  HPLC Identification of toxic non-protein amino acids in the tropical leguminous tree Acacia angustissima.  Asian-Australasian Journal of Animal Science 13 Supplement July 2000 B: 159.

18.     Long, B.M., Jones, G.J. and ORR, P.T. (2001).  Cellular microcystin content in N-limited Microcystis aeruginosa can be predicted from growth rate.  Applied and Environmental Microbiology67(1) 278-283.

DOI: 10.1128/AEM.67.1.278-283.2001

19.     ORR, P.T., Jones, G.J., Hunter, R.A., Berger, K., De Paoli, D.A. and Orr, C.L.A. (2001).  Ingestion of toxic Microcystis aeruginosa by dairy cattle and the implications for microcystin contamination of milk.  Toxicon39(12) 1847-1854.

DOI: 10.1016/S0041-0101(01)00166-0

20.     ORR, P.T., Jones, G.J., Hunter, R.A., and Berger, K. (2003).  Exposure of beef cattle to sub-clinical doses of Microcystis aeruginosa:  toxin bioaccumulation, physiological effects and human health risk assessment.  Toxicon41(5) 613-620.

DOI: 10.1016/S0041-0101(03)00006-0

21.     ORR, P.T., Jones G.J. and Douglas, G.B.  (2004).  Response of cultured Microcystis aeruginosa from the Swan River, Australia, to elevated salt concentration and consequences for bloom and toxin management in estuaries.  Marine and Freshwater Research55(3) 277-283.

DOI: 10.1071/MF03164

22.     ORR, P.T., Jones, G.J. and Hamilton, G.  (2004).  Removal of saxitoxins from drinking water by granular activated carbon, ozone and hydrogen peroxide – implications for compliance with the Australian drinking water guidelines.  Water Research38(20) 4455 – 4461.

DOI: 10.1016/j.watres.2004.08.024

23.     Douglas, G., Palmer, M., Caitcheon, G., and ORR, P.  (2007). Identification of sediment sources in aquatic systems: provenance of sediment in Lake Wivenhoe, south east Queensland. Marine and Freshwater Research58(9) 793-810.

DOI: 10.1071/MF05175

24.     ORR, P.T., Rasmussen, J.P., Burford, M.A., Eaglesham, G.K and Lennox, S.M. (2010).  Evaluation of quantitative real time PCR to characterise spatial and temporal variations in cyanobacteria, Cylindrospermopsis raciborskii (Woloszynska) Seenaya et Subba Raju and cylindrospermopsin concentrations in three subtropical Australian reservoirs.  Harmful Algae9 243-254.

DOI: 10.1016/j.hal.2009.11.001

25.     ORR, P.T., Rasmussen, J.P., Burford, M.A., Eaglesham, G.K and Lennox, S.M. (2010).  Corrigendum.  Evaluation of quantitative real time PCR to characterise spatial and temporal variations in cyanobacteria, Cylindrospermopsis raciborskii (Woloszynska) Seenaya et Subba Raju and cylindrospermopsin concentrations in three subtropical Australian reservoirs.  Harmful Algae10 234.

DOI: 10.1016/j.hal.2010.09.006

26.     Holland, D.P., Pantorno, A., ORR, P.T., Stojkovic, S. and Beardall, J. (2012).  The impacts of a high CO 2 environment on a bicarbonate user; the cyanobacterium Cylindrospermopsis raciborskii. Water Research46(5) 1430-1437.

DOI: 10.1016/j.watres.2011.11.015

27.     Sinha, R., Pearson, L.A., Davis, T.W., Burford, M.A., ORR, P.T., Neilan, B.A.  (2012).  Increased incidence of Cylindrospermopsis raciborskii in temperate zones - is climate change responsible? Water Research46(5) 1408-1419.

DOI: 10.1016/j.watres.2011.12.019

28.     Cao, H., Recknagel, F., ORR, P.T.  (2013).  Enhanced functionality of the redesigned hybrid evolutionary algorithm HEA demonstrated by predictive modelling of algal growth in the Wivenhoe Reservoir, Queensland (Australia).  Ecological Modelling252 32–43.

DOI: 10.1016/j.ecolmodel.2012.09.009

29.     Cao, H; Recknagel, F and ORR, P.T. (2013).  Parameter optimization algorithms for evolving rule models applied to freshwater ecosystems. Transactions on Evolutionary Computation.

DOI: 10.1109/TEVC.2013.2286404

30.     Davis, T.W., ORR, P.T., Boyer, G.L. and Burford, M.A. (2014).  Investigating the production and release of cylindrospermopsin and deoxycylindrospermopsin by Cylindrospermopsis raciborskii over a natural growth cycle.  Harmful Algae. 31 18–25

DOI: 10.1016/j.hal.2013.09.007

31.     Recknagel F., ORR, P.T., Cao, H. (2014).  Inductive reasoning and forecasting of population dynamics of Cylindrospermopsis raciborskii in three sub-tropical reservoirs by evolutionary computation. Harmful Algae. 31 26–34.

DOI: 10.1016/j.hal.2013.09.004

32.     Pierangelini, M., Stojkovic , S., ORR, P.T. and Beardall, J. (2014) Photosynthetic characteristics of two Cylindrospermopsis raciborskii strains differing in their toxicity. Journal of Phycology. 50(2) 292–302.

DOI: 10.1111/jpy.12157

33.     Burford, M.A., Davis, T.W., ORR, P.T., Sinha, R., Willis, A. and Neilan, B.A. (2014) Nutrient-related changes in the toxicity of field blooms of the cyanobacterium, Cylindrospermopsis raciborskii. FEMS Microbiolial Ecology89 135–148.

DOI: 10.1111/1574-6941.12341

34.     Pierangelini, M., Stojkovic, S., ORR, P.T., Beardall, J. (2004)  Elevated CO 2 causes changes in the photosynthetic apparatus of a toxic cyanobacterium, Cylindrospermopsis raciborskii. Journal of  Plant Physiology 171:1091-98.

DOI: 10.1016/j.jplph.2014.04.003

Papers - Refereed Conference Proceedings (2)

35.     Mitchell, D.S. and ORR, P.T.  (1985). Myriophyllum in Australia. Proceedings 1 st International Symposium on Watermilfoil (Myriophyllum spicatum) and Related Haloragaceae Species. 23 – 24 July 1985. Vancouver, British Columbia, Canada. Sponsored by the Aquatic Plant Management Society, Vicksburg.

36.     Cao, H., Recknagel, F. and ORR, P.T.  (2012) The Experimental Study of Population-based Parameter Optimization Algorithms on Rule-based Ecological Modelling. 2012 IEEE World Congress on Computational Intelligence. 100 – 15 June 2012.  Brisbane, Queensland, Australia.

DOI: 10.1109/CEC.2012.6252957

Book Chapters (4)

37.     Blackburn, S., Bolch, C., Jones, G., Negri, A. and ORR, P.  (1997).  Cyanobacterial blooms: Why are they toxic? (The regulation of toxin production). In: J.R. Davis ed. Managing algal blooms - Outcomes from CSIRO’s multi-divisional blue-green algal program. ISBN 0 643 06049 9.  Ch 6 pp 67 – 77. CSIRO Canberra.

38.     Jones, G.J. and ORR, P.T.  (2003) Bloom-forming blue-green algae (Cyanobacteria).  In:  Sainty, G.R and Jacobs, S.W.L. eds.  Water Plants of Australia (4 th Edition). ISBN: 9780958105514.  Sainty and Associates, Sydney.

39.     Mulvenna, V. and ORR, P.T. (2012). Management of Cyanobacteria in Australia. In: Chorus, I. Ed. Current approaches to cyanotoxin risk assessment, risk management and regulations in different countries. 2nd Edition. ISSN 1862-4804.  Federal Environmental Agency (Umweltbundesamt), Berlin.

40.     ORR, P.T. (In Press). Cyanobacterial Management. In: Macnish, S. Ed. Guidelines for the Environmental Management of Dams in Australia. 2nd Edition. The Australian National Committee on Large Dams Incorporated. Hobart.  Accepted 15 January 2011.

Consultancy Reports (17)

41.     Jones G.J., Falconer, I.R., ORR, P.T., Choice, M., Minato, W., Prior, J. Orr, C. and Negri, A.  Factors affecting the toxicity of cyanobacterial (blue-green algal) blooms.  A report to Land and Water Resources Research and Development Corporation Report No.  CWN1.

42.     Jones, G.J., Davis M., ORR, P. and Fairweather, P.  Setting target river flows for the prevention of cyanobacterial blooms.  A report to Land and Water Resources Research and Development Corporation Report No.  CWN10.

43.     ORR, P.T., O’Halloran, K., Friend, R., Jones, G.J. and Orr, C. (1999).  Efficacy of ozone in association with biologically activated carbon (BAC) or peroxide to remove saxitoxins from drinking water.  A report to Gold Coast City Council. CSIRO Consultancy Report No. 99/16.39,11,14

44.     Jones, G.J. and ORR, P.T. (2000).  Development of a Toxic Cyanobacterial Management Plan for Southern Rural Water, Victoria.  Stage 1.  Water use risks, water storage vulnerability, advisory levels, and best practices.  A report to Southern Rural Water.

45.     ORR, P.T., Jones, G.J. and Orr, C.L.A. (2000).  Effect of salinity shock on the survival of toxic Microcystis aeruginosa from the Swan River, WA.  A report to the Western Australian Waters and Rivers Commission.

46.     Douglas G.B., Burford, M. A., ORR P. T. and Thompson, P.  (2001).  Assessment of sediment nutrient fluxes from four sites in North Pine Dam, south east Queensland.  A report to South-East Queensland Water Corporation.

47.     ORR, P.T., Sherman, B., Matveev, V.F. and Gehrke, P.C.  (2002).  Port of Hay Point water supply system.  Buffer storage and pipeline cyanobacterial risk assessment and management plan.  A Report to Ports Corporation of Queensland.

48.     Sherman, B., ORR, P.T. and Vigneswaran, B.  (2002).  Cyanobacterial (Blue Green Algae) Risk Assessment Management Strategy.  A Report to Sydney Catchment Authority.

49.     Douglas, G.B., Caitcheon, G.G., Pinchand, G.T., Adeney, J.A. and ORR, P.T.  (2002). Sediment sourcing in Lake Wivenhoe: Stage 1 - Reconnaissance lake sediment sampling survey. CSIRO Land and Water. A Report to South East Queensland Water Corporation.

50.     Douglas, G.B., Caitcheon G.G., Palmer, M. J., Pinchand, G.T., Adeney, J.A. and ORR, P.T.  (2003). Sediment sourcing in Lake Wivenhoe: Stage 2 - Identification of Lake Sediment Sources. CSIRO Land and Water. A Report to South East Queensland Water Corporation.

51.     ORR, P.T.  (2005).  Revision of the New Zealand Drinking Water Standards Cyanobacterial Fact Sheets.  A Consultancy for NIWA NZ to the New Zealand Ministry of Health.

52.     ORR, P.T.  (2006).  A Risk Based Assessment for use of Irrigation Water Contaminated with Anabaena circinalis in the Macalister Irrigation District.  A report to Southern Rural Water, Victoria.

53.     ORR, P.T. and Schneider, P.M. (2006).  Toxic Cyanobacteria Risk Assessment - Reservoir Vulnerability and Water Use Best Practice.  A report to South East Queensland Water Corporation.

54.     Schneider, P.M., ORR, P.T., Townsley, R., Lutton, M.R. and Andrew. M. (2006).  Drought Water Quality Risk Assessment.  A report to the Regional Drought Management Strategy, Brisbane.

55.     Schneider, P.M., ORR, P.T., Townsley, R., Lutton, M.R. and Andrew. M. (2008).  Drought Water Quality Risk Assessment.  A report to South East Queensland Water Corporation, Brisbane.

56.     Pantorno, A., Stojkovic, S., Beardall, J. and ORR, P. (2008).  Effects of alkalinity on the growth and photosynthesis of Cylindrospermopsis raciborskii.  A report to Seqwater, Brisbane.

57.     Holland, D., Beardall, J. and ORR, P.  (2009).  Effects of alkalinity on the growth rate of Cylindrospermopsis raciborskii. A report to Seqwater.