title: Long term monitoring of photosystem II herbicides--correlation with remotely sensed freshwater extent to monitor changes in the quality of water entering the Great Barrier Reef, Australia.
abstract: Photosystem II (PSII) herbicides are used in large quantities on agricultural lands adjoining the Great Barrier Reef (GBR). Routine monitoring at 14 sites in inshore waters of the GBR using passive sampling techniques detected diuron (32-94% of sampling periods) at maximum concentrations of 1.7-430ng L(-1) in the relatively pristine Cape York Region to the Mackay Whitsunday Region, respectively. A PSII herbicide equivalent (PSII-HEq) index developed as an indicator for reporting was dominated by diuron (average contribution 89%) and typically increased during the wet season. The maximum PSII-HEq indicates the potential for photosynthetic inhibition of diatoms, seagrass and coral-symbionts. PSII herbicides were significantly positively correlated with remotely sensed coloured dissolved organic matter, a proxy for freshwater extent. Combining these methods provides for the first time the potential to cost-effectively monitor improvements in water quality entering the GBR with respect to exposure to PSII herbicides.
authors.affiliation: The University of Queensland, The National Research Centre for Environmental Toxicology (Entox), Coopers Plains, Brisbane, QLD 4108, Australia. k.kennedy@uq.edu.au
authors.forename: Karen
authors.initials: K
authors.lastname: Kennedy
authors.forename: Thomas
authors.initials: T
authors.lastname: Schroeder
authors.forename: Melanie
authors.initials: M
authors.lastname: Shaw
authors.forename: David
authors.initials: D
authors.lastname: Haynes
authors.forename: Stephen
authors.initials: S
authors.lastname: Lewis
authors.forename: Christie
authors.initials: C
authors.lastname: Bentley
authors.forename: Chris
authors.initials: C
authors.lastname: Paxman
authors.forename: Steve
authors.initials: S
authors.lastname: Carter
authors.forename: Vittorio E
authors.initials: VE
authors.lastname: Brando
authors.forename: Michael
authors.initials: M
authors.lastname: Bartkow
authors.forename: Laurence
authors.initials: L
authors.lastname: Hearn
authors.forename: Jochen F
authors.initials: JF
authors.lastname: Mueller
mesh_terms: D001315:Australia; D003247:Conservation of Natural Resources; D057894:Coral Reefs; D004784:Environmental Monitoring / Q000379:methods*; D005618:Fresh Water / Q000737:chemistry*; D006540:Herbicides / Q000032:analysis*; D010788:Photosynthesis / Q000187:drug effects; D045332:Photosystem II Protein Complex / Q000187:drug effects; D058998:Remote Sensing Technology; D012621:Seasons; D012623:Seawater / Q000737:chemistry; D018531:Spacecraft; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D006540:Herbicides; D045332:Photosystem II Protein Complex; D014874:Water Pollutants, Chemical