Figure 1.

Starting composition and selective bacterial removal of each of the six neutral sugar hydrolysis products (DCNS) among coral and algal exudate treatments. Experimental treatments are average-neighbor clustered according to DCNS composition. (a) The starting concentration of each sugar component of DCNS among treatments and controls. (b) The mole % of each sugar in starting exudates after control correction. (c) The change in concentration of each sugar component of DCNS in exudates over 48 h after control correction. (d) The mole % of each sugar in the utilized portion of each exudate (that is, starting—remaining) after control correction. Note that exudates clustered according to source both in terms of absolute concentration (a) and in terms of relative contribution (b) at the start of the experiment, and all exudates were clearly distinct from control treatments and ambient reef water collected at the start of the experiment. Note also that utilization profiles of exudates by bacterioplankton differed according to treatment both in terms of absolute concentrations removed (c) and in terms of proportional removal of exuded DCNS components (d).