Combining in-situ water quality and remotely sensed data across spatial and temporal scales to measure variability in wet season chlorophyll-a: Great Barrier Reef lagoon (Queensland, Australia)

IntroductionCombining in-situ data from single-point time series with remotely sensed spatial data allowed a greater elucidation of changes in chlorophyll-a concentrations through wet season conditions in the Great Barrier Reef coastal waters.MethodsSingle-point time-series data were collected from 2006 to 2012 during high river flow conditions to assess changes in phytoplankton biomass (measured as chlorophyll-a). Additionally, three flood plume water types, derived from classified true-colour Aqua moderate resolution imaging spectroradiometer (MODIS) images, were used to group single-point time-series data for the phytoplankton biomass assessment.ResultsSurvey data illustrate the heterogeneity of chlorophyll-a distribution over seasonal and inter-annual cycles and the difficulty in describing community responses through the wet season. The spatial data demonstrate distinct regional differences throughout the Great Barrier Reef. The high chlorophyll-a concentrations measured in flood plume waters immediately adjacent to the inshore, highly turbid 'inner’ flood plume are a product of sufficient light, given most of the suspended solids have settled from the plume, and the availability of sufficient nutrients, which drive higher phytoplankton production and characterise the formation of secondary stage flood plumes. The formation and extent of these secondary flood plumes were mapped using MODIS true-colour satellite imagery. The distance and the location of the secondary plume water are reliant on flow, coastal hydrodynamics, and biological activity.ConclusionsThe combination of in-situ data and remotely sensed data provides information on the complexity of these coastal processes during the wet season and offers managers a more comprehensive understanding of the extent of nutrient enrichment in the Great Barrier Reef coastal area and the potential influence of flood plumes on coastal marine ecosystems.

[1]  Xiao‐Hai Yan,et al.  Tracking of a Chesapeake Bay estuarine outflow plume with satellite-based ocean color data , 2005 .

[2]  Robert L Pressey,et al.  A novel approach to model exposure of coastal-marine ecosystems to riverine flood plumes based on remote sensing techniques. , 2013, Journal of environmental management.

[3]  G. Jones,et al.  The seasonal variation of dissolved nutrients, chlorophyll a and suspended sediments at Nelly Bay, Magnetic Island , 2003 .

[4]  S. Bricker,et al.  An integrated methodology for assessment of estuarine trophic status , 2003 .

[5]  Jon Barry,et al.  Extending the phytoplankton tool kit for the UK Water Framework Directive: indicators of phytoplankton community structure , 2009, Hydrobiologia.

[6]  A. Gitelson,et al.  A bio-optical algorithm for the remote estimation of the chlorophyll-a concentration in case 2 waters , 2009 .

[7]  J. Brodie,et al.  Monitoring chlorophyll in the Great Barrier Reef lagoon: trends and variability , 1997 .

[8]  Menghua Wang,et al.  The NIR-SWIR combined atmospheric correction approach for MODIS ocean color data processing. , 2007, Optics express.

[9]  J. Brodie,et al.  In the other 90%: phytoplankton responses to enhanced nutrient availability in the Great Barrier Reef Lagoon. , 2005, Marine pollution bulletin.

[10]  K. Fabricius,et al.  Shifting roles of heterotrophy and autotrophy in coral energetics under varying turbidity. , 2000, Journal of experimental marine biology and ecology.

[11]  Bertram Ostendorf,et al.  Overview: Spatial information and indicators for sustainable management of natural resources , 2011 .

[12]  Britta Schaffelke,et al.  Spatial extent of riverine flood plumes and exposure of marine ecosystems in the Tully coastal region, Great Barrier Reef , 2009 .

[13]  Charles R. McClain,et al.  Data analysis system developed for ocean color satellite sensors , 2001 .

[14]  Catherine J. Collier,et al.  Light thresholds derived from seagrass loss in the coastal zone of the northern Great Barrier Reef, Australia , 2012 .

[15]  Jon Brodie,et al.  Are increased nutrient inputs responsible for more outbreaks of crown-of-thorns starfish? An appraisal of the evidence. , 2005, Marine pollution bulletin.

[16]  Toby Elmhirst,et al.  Connectivity, regime shifts and the resilience of coral reefs , 2009, Coral Reefs.

[17]  Thomas Schroeder,et al.  Reef Rescue Marine Monitoring Program: Using remote sensing for GBR-wide water quality. Final report for 2012/13 activities , 2013 .

[18]  D. Anderson,et al.  Red tides : biology, environmental science, and toxicology : proceedings of the First International Symposium on Red Tides held November 10-14, 1987, in Takamatsu, Kagawa Prefecture, Japan , 1989 .

[19]  André Valente,et al.  On the observability of the fortnightly cycle of the Tagus estuary turbid plume using MODIS ocean colour images , 2009 .

[20]  Eric Wolanski,et al.  Fine sediment and nutrient dynamics related to particle size and floc formation in a Burdekin River flood plume, Australia. , 2012, Marine pollution bulletin.

[21]  I. Bohnet,et al.  Terrestrial pollutant runoff to the Great Barrier Reef: An update of issues, priorities and management responses. , 2012, Marine pollution bulletin.

[22]  Ryan D R Turner,et al.  River loads of suspended solids, nitrogen, phosphorus and herbicides delivered to the Great Barrier Reef lagoon. , 2012, Marine pollution bulletin.

[23]  O. Yunev,et al.  Long-term variations of surface chlorophyll a and primary production in the open Black Sea , 2002 .

[24]  J. Brodie,et al.  Flood plumes in the Great Barrier Reef : spatial and temporal patterns in composition and distribution , 2001 .

[25]  J. Brodie,et al.  Nutrients in Australian tropical rivers: changes with agricultural development and implications for receiving environments , 2005 .

[26]  Robert J. Orth,et al.  Assessing Water Quality with Submersed Aquatic Vegetation , 1993 .

[27]  Lawrence W. Harding,et al.  Long-term increase of phytoplankton biomass in Chesapeake Bay, 1950-1994* , 1997 .

[28]  H. Gordon,et al.  Remote Assessment of Ocean Color for Interpretation of Satellite Visible Imagery: A Review , 1983 .

[29]  J. Cloern.  Our evolving conceptual model of the coastal eutrophication problem , 2001 .

[30]  L. Prieur,et al.  Analysis of variations in ocean color1 , 1977 .

[31]  Steve Carter,et al.  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. , 2012, Marine pollution bulletin.

[32]  David Haynes,et al.  Assessment of the eutrophication status of the Great Barrier Reef lagoon (Australia) , 2011 .

[33]  Jon Brodie,et al.  Spatial and temporal patterns of near-surface chlorophyll a in the Great Barrier Reef lagoon , 2007 .

[34]  Vittorio E Brando,et al.  Inter-annual variability of wet season freshwater plume extent into the Great Barrier Reef lagoon based on satellite coastal ocean colour observations. , 2012, Marine pollution bulletin.

[35]  P. Naik,et al.  Light absorption properties of southeastern Bering Sea waters: Analysis, parameterization and implications for remote sensing , 2013 .

[36]  K. Fabricius.  Effects of terrestrial runoff on the ecology of corals and coral reefs: review and synthesis. , 2005, Marine pollution bulletin.

[37]  M. Furnas,et al.  Nitrogen levels in the Tully River--a long-term view. , 2001, Water science and technology : a journal of the International Association on Water Pollution Research.

[38]  Jon Brodie,et al.  A critical review of environmental management of the 'not so Great' Barrier Reef , 2012 .

[39]  Britta Schaffelke,et al.  Water quality in the Great Barrier Reef region: responses of mangrove, seagrass and macroalgal communities. , 2005, Marine pollution bulletin.

[40]  L. Kriwoken.  Great Barrier Reef Marine Park , : Intergovernmental relations , 1991 .

[41]  J. Brodie,et al.  Current status of nutrient levels and other water quality parameters in the Great Barrier Reef , 1996 .

[42]  L. McKinna,et al.  Monitoring and mapping of flood plumes in the Great Barrier Reef based on in-situ and remote sensing observations , 2012 .

[43]  J. Brodie,et al.  Terrestrial discharge into the Great Barrier Reef Lagoon: nutrient behavior in coastal waters. , 2005, Marine pollution bulletin.

[44]  M. Schaepman,et al.  Review of constituent retrieval in optically deep and complex waters from satellite imagery , 2012 .

[45]  Yu. I. Sorokin,et al.  Plankton of the central Great Barrier Reef: abundance, production and trophodynamic roles , 2010, Journal of the Marine Biological Association of the United Kingdom.

[46]  W. Boynton,et al.  A comparative analysis of eutrophication patterns in a temperate coastal lagoon , 1996 .

[47]  G. De’ath,et al.  Three lines of evidence to link outbreaks of the crown-of-thorns seastar Acanthaster planci to the release of larval food limitation , 2010, Coral Reefs.

[48]  Ángel Borja,et al.  Water quality monitoring in Basque coastal areas using local chlorophyll- a algorithm and MERIS images , 2012 .

[49]  A. Valle‐Levinson,et al.  Bathymetric effects on estuarine plume dynamics , 2013 .

[50]  G. De’ath,et al.  The 27–year decline of coral cover on the Great Barrier Reef and its causes , 2012, Proceedings of the National Academy of Sciences.

[51]  K. Fabricius,et al.  Factors Determining the Resilience of Coral Reefs to Eutrophication: A Review and Conceptual Model , 2011 .

[52]  L. McKinna,et al.  Mapping the pollutants in surface riverine flood plume waters in the Great Barrier Reef, Australia. , 2012, Marine pollution bulletin.

[53]  J. Kleypas,et al.  Coral reef development under naturally turbid conditions: fringing reefs near Broad Sound, Australia , 1996, Coral Reefs.

[54]  D. Alongi,et al.  The cycling and fate of terrestrially-derived sediments and nutrients in the coastal zone of the Great Barrier Reef shelf. , 2005, Marine pollution bulletin.

[55]  J. Brodie,et al.  Quantifying the sources of pollutants in the Great Barrier Reef catchments and the relative risk to reef ecosystems. , 2012, Marine pollution bulletin.

[56]  A. Morel.  Optical modeling of the upper ocean in relation to its biogenous matter content (case I waters) , 1988 .

[57]  Kohji Iida,et al.  Satellite-measured temporal and spatial variability of the Tokachi River plume , 2008 .

[58]  T. Walker.  Dependance of phytoplankton chlorophyll on bottom resuspension in Cleveland Bay, northern Queensland , 1981 .

[59]  Zvy Dubinsky,et al.  Coral reefs : an ecosystem in transition , 2011 .

[60]  Jon Brodie,et al.  Exposure of inner-shelf reefs to nutrient enriched runoff entering the Great Barrier Reef Lagoon: post-European changes and the design of water quality targets. , 2006, Marine pollution bulletin.

[61]  J. Brodie,et al.  Relationships between land use and nutrient concentrations in streams draining a ‘wet-tropics’ catchment in northern Australia , 2009 .

[62]  J. Froidefond,et al.  Spectral remote sensing reflectances of coastal waters in French Guiana under the Amazon influence , 2002 .

[63]  Eduardo Teixeira da Silva,et al.  Reef Rescue Marine Monitoring Program: Flood plume monitoring annual report 2010-11. Incorporating results from the Extreme Weather Response Program flood plume monitoring , 2012 .

[64]  D. Alongi,et al.  Regional-scale nitrogen and phosphorus budgets for the northern (14°S) and central (17°S) Great Barrier Reef shelf ecosystem , 2011 .

[65]  M. Furnas.  Cyclonic disturbance and a phytoplankton bloom in a tropical shelf ecosystem , 1989 .

[66]  Britta Schaffelke,et al.  Assessing the additive risks of PSII herbicide exposure to the Great Barrier Reef. , 2012, Marine pollution bulletin.

[67]  W. Geyer,et al.  The transport, transformation and dispersal of sediment by buoyant coastal flows , 2004 .

[68]  G. Rayment,et al.  Downstream Effects of Land Use , 1996 .

[69]  Britta Schaffelke,et al.  Water quality in the inshore Great Barrier Reef lagoon: Implications for long-term monitoring and management. , 2012, Marine pollution bulletin.

[70]  V. Klemas,et al.  Remote Sensing of Coastal Plumes and Ocean Fronts: Overview and Case Study , 2011 .

[71]  J. Brodie,et al.  Dispersal of suspended sediments and nutrients in the Great Barrier Reef lagoon during river-discharge events: conclusions from satellite remote sensing and concurrent flood-plume sampling , 2010 .

[72]  M. Sandstrom,et al.  Dissolved nutrient fluxes from the nearshore sediments of Bowling Green Bay, central Great Barrier Reef Lagoon (Australia) , 1987 .

[73]  K. Fabricius,et al.  Rapid Smothering of Coral Reef Organisms by Muddy Marine Snow , 2000 .

[74]  Pornsook Chongprasith.  Nutrient release and nitrogen transformations resulting from resuspension of Great Barrier Reef shelf sediments , 1992 .

[75]  Vittorio E Brando,et al.  Adaptive semianalytical inversion of ocean color radiometry in optically complex waters. , 2012, Applied optics.

[76]  C. Lorenzen,et al.  Spectra of Backscattered Light from the Sea Obtained from Aircraft as a Measure of Chlorophyll Concentration , 1970, Science.

[77]  A. Steven,et al.  Long-term chlorophyll monitoring in the Great Barrier Reef Lagoon : status report 1, 1993-1995 , 1998 .

[78]  C. McClain.  A decade of satellite ocean color observations. , 2009, Annual review of marine science.