Ecological Archives E093-011-A1
S. Uthicke, F. Patel, and R. Ditchburn. 2012. Elevated land runoff after European settlement perturbs persistent foraminiferal assemblages on the Great Barrier Reefs. Ecology 93:111–121.
Appendix A. Locality map and pictures of two locations at extremes of the water quality gradient.
Fig. A1. Locality Map of fringing reefs in the Whitsunday area of the on the Great Barrier Reef, Australia.
FIG. A2. Locations at the extreme of the water quality gradient studied. Note differences in water color at Deloraine Island (Top, classified as outer island reef in the present study) and Long Island (bottom). Both pictures were taken 'on a good day', however, the water remains blue on outer island reefs even during strong trade wind conditions, whereas green water (caused by elevated chlorophyll content) on inner reefs can become brown due to sediments from flood plumes or sediments re-suspended from the sea floor. Water quality at these locations was studied over a 6-year program during summer (wet season) and winter (dry season). Detailed statistical analyses (Cooper et al., 2007; Uthicke and Altenrath 2010) showed that all water quality parameters were significantly higher at inner locations; and that the difference was more distinct during wet-seasons.
In summary (averaged over years, season and island, N = 20 averages for each comparison):
Dissolved inorganic nitrogen
0.35 µmol l-1 (1SE = 0.09 µmol l-1) on inner reefs
0.17 µmol l-1 (1SE = 0.02 µmol l-1) on outer-island reefs
Total suspended solids
2.99 mg l-1 (1SE = 0.69 mg l-1) on inner reefs
1.32 mg l-1 (1SE = 0.15 mg l-1) on outer-island reefs
Chlorophyll α
0.51 µg l-1 (1 SE = 0.05 µg l-1) on inner reefs
0.43 µg l-1 (1 SE = 0.05 µg l-1) on outer-island reefs
Literature Cited
Cooper, T., S. Uthicke, C. Humphrey, and K. Fabricius. 2007. Gradients in water column nutrients, sediments, irradiance and coral reef development in the Whitsunday Region, central Great Barrier Reef. Estuarine Coastal and Shelf Science 74:458–470.
Uthicke, S., and C. Altenrath. 2010. Water column nutrients control growth and C : N ratios of symbiont-bearing benthic foraminifera on the Great Barrier Reef, Australia. Limnology and Oceanography 55:1681–1669.