Spatial and temporal patterns of near-surface chlorophyll a in the Great Barrier Reef lagoon
J. Brodie A D ,A Australian Centre for Tropical Freshwater Research, James Cook University, James Cook Drive, Townsville, Qld 4811, Australia.
B Australian Institute of Marine Science, PMB 3, Townsville MC, Townsville, Qld 4810, Australia.
C Centre for Environment, Fisheries & Aquaculture Science, Pakefield Road, Lowestoft, Suffolk NR33 OHT, UK.
D Corresponding author. Email: jon.brodie@jcu.edu.au
Marine and Freshwater Research 58(4) 342-353 https://doi.org/10.1071/MF06236
Submitted: 3 December 2006 Accepted: 10 January 2007 Published: 13 April 2007
Abstract
Surface chlorophyll a concentrations in the Great Barrier Reef (GBR) lagoon were monitored at individual stations for periods of 6 to 12 years. The monitoring program was established to detect spatial and temporal changes in water quality resulting from increased loads of nutrients exported from the catchments adjoining the GBR. Sampling occurred monthly at up to 86 sites that were located in transects across the width of the continental shelf. In the central and southern GBR (16–21°S), there was a persistent cross-shelf chlorophyll a gradient, with higher concentrations near the coast. No cross-shelf gradient was observed in the far northern GBR (12–15°S). Mean chlorophyll a concentrations in the far northern GBR (0.23 µg L–1) were less than half those in the south and central GBR (0.54 µg L–1). Chlorophyll a varied seasonally within regions, with mean summer-wet season (December–April) concentrations ~50% greater than those in the winter-dry season (May–November). Sub-annual, inter-annual and event-related variations in chlorophyll a concentrations were observed in several zones. Multi-year patterns in concentrations suggest that relatively short (5–8 years) time series may give spurious estimates of secular trends. Higher chlorophyll a concentrations in inshore waters south of 16°S were most likely related to the levels of river nutrient delivery associated with agricultural development on adjacent catchments.
Additional keywords: monitoring, phytoplankton.
Andrews, J. C. , and Gentian, P. (1982). Upwelling as a source of nutrients for the Great Barrier Reef ecosystems: a solution to Darwin's question. Marine Ecology Progress Series 8, 257–269.
Bell, P. R. F. , and Elmetri, I. (1995). Ecological indicators of large-scale eutrophication in the Great Barrier Reef Lagoon. Ambio 24(4), 208–215.
Brinkman, R. , Wolanski, E. , Deleersnijder, E. , McAllister, F. , and Skirving, W. (2002). Oceanic inflow from the Coral Sea into the Great Barrier Reef. Estuarine, Coastal and Shelf Science 54, 655–668.
| Crossref | GoogleScholarGoogle Scholar |
Brodie, J. , Christie, C. , Devlin, M. , Haynes, D. , Morris, S. , Ramsay, M. , Waterhouse, J. , and Yorkston, H. (2001). Catchment management and the Great Barrier Reef. Water Science and Technology 43(9), 203–211.
| PubMed |
Fabricius, K. E. (2005). Effects of terrestrial runoff on the ecology of corals and coral reefs. Marine Pollution Bulletin 50, 125–146.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Furnas, M. J. (1991). Net in situ growth rates of phytoplankton in an oligotrophic, tropical shelf ecosystem. Limnology and Oceanography 36, 13–29.
Furnas, M. J. , and Mitchell, A. W. (1986). Phytoplankton dynamics in the central Great Barrier Reef. I. Seasonal changes in biomass and community structure and their relation to intrusive activity. Continental Shelf Research 6, 363–384.
| Crossref | GoogleScholarGoogle Scholar |
Furnas, M. J. , and Mitchell, A. W. (1996). Nutrient inputs into the central Great Barrier Reef (Australia) from subsurface intrusions of Coral Sea waters: a two-dimensional displacement model. Continental Shelf Research 16, 1127–1148.
| Crossref | GoogleScholarGoogle Scholar |
Furnas, M. , Mitchell, A. , Skuza, M. , and Brodie, J. (2005). In the other 90 percent: phytoplankton responses to enhanced nutrient availability in the GBR lagoon. Marine Pollution Bulletin 51(1–4), 253–265.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Liston, P. , Furnas, M. J. , Mitchell, A. W. , and Drew, E. A. (1992). Local and mesoscale variability of surface water temperature and chlorophyll in the northern Great Barrier Reef, Australia. Continental Shelf Research 12, 907–922.
| Crossref | GoogleScholarGoogle Scholar |
McKergow, L. A. , Prosser, I. P. , Hughes, A. O. , and Brodie, J. (2005). Regional scale nutrient modelling: exports to the Great Barrier Reef World Heritage Area. Marine Pollution Bulletin 51, 186–199.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Revelante, N. , and Gilmartin, M. (1982). Dynamics of phytoplankton in the Great Barrier Reef lagoon. Journal of Plankton Research 4, 47–76.
| Crossref | GoogleScholarGoogle Scholar |
Tada, K. , Sakai, K. , Nakano, Y. , Takemura, A. , and Montani, S. (2003). Size-fractionated phytoplankton biomass in coral reef waters off Sesoko Island, Okinawa, Japan. Journal of Plankton Research 25, 991–997.
| Crossref | GoogleScholarGoogle Scholar |
van Woesik, R. , Tomascik, T. , and Blake, S. (1999). Coral assemblages and physico-chemical characteristics of the Whitsunday Islands: evidence of recent community changes. Marine and Freshwater Research 50, 427–440.
Walker, T. A. (1981). Dependence of phytoplankton chlorophyll on bottom resuspension in Cleveland Bay, northern Queensland. Australian Journal of Marine and Freshwater Research 32, 981–986.
| Crossref | GoogleScholarGoogle Scholar |
Wasmund, N. , and Uhlig, S. (2003). Phytoplankton trends in the Baltic Sea. ICES Journal of Marine Science 60, 177–186.
| Crossref | GoogleScholarGoogle Scholar |
Wolanski, E. , Richmond, R. , McCook, L. , and Sweatman, H. (2003). Mud, marine snow and coral reefs. American Scientist 91, 44–51.
| Crossref | GoogleScholarGoogle Scholar |