Fig 1.
Experiments performed with early life history stages of Acropora tenuis exposed to different treatments of temperature and nutrient enrichment.
Black bars indicate the stages involved in each experiment.
Table 1.
Water quality parameters for the different temperatures and nutrient enrichment (low in white, medium in light grey and high in dark grey) at the start of each experiment.
Values shown are means and standard deviations. Number of replicates: 2 per water quality factor and treatment for Experiments 1 and 2, 18 per treatment for Experiment 3 at 27°C, and 6 per treatment for Experiment 3 at 30 and 32°C temperature. Ranges from seawater values from the inshore of the Great Barrier Reef are added for comparison [53].
Table 2.
Experimental conditions used in each experiment performed at different temperatures and nutrient enrichment.
Fig 2.
Effects of temperature and nutrient enrichment on the percentage of fertilized eggs (blue line, black circles; Experiment 1a) and abnormal embryos (red line, open circles; Experiment 1b) of Acropora tenuis. Control treatment: ‘low’ nutrient enrichment and at temperature = 27°C. Solid lines indicate fitted GLM trend lines, while dashed lines are 95% confidence intervals.
Table 3.
Results of treatments effects on Acropora tenuis early life history stages based on generalized linear models (GLM) with log-link function temperature (Temp) and nutrient enrichment (Nut) as fixed factors and tank as random error term.
Significance at p<0.05 is shown in bold. Refer to S2 Table for detailed information for the analyses.
Fig 3.
a) Percentage larval survivorship 5 days after fertilization for Acropora tenuis reared under different temperatures and nutrient enrichment [low (open circles), medium (grey circles), high (black circles); Experiment 1c]. b) Settlement rates for larvae of A. tenuis that had being fertilized, reared and settled under different temperatures and nutrient enrichment (Experiment 1d). Control treatment: ‘low’ nutrient enrichment and at temperature = 27°C. Solid lines indicate fitted GLM trends, while dashed lines are 95% confidence intervals. Individual points are jittered horizontally for clarity.
Fig 4.
Proportion of 5 days old Acropora tenuis larvae, fertilized and reared under control conditions (27°C and FSW) but settled under different temperatures and nutrient enrichment [low (open circles), medium (grey circles), high (black circles); Experiment 2].
Control treatment: ‘low’ nutrient enrichment and at temperature = 27°C. Solid lines indicate fitted GLM trends, dashed lines are 95% confidence intervals. Individual points are jittered horizontally for clarity.
Fig 5.
Four-month-old Acropora tenuis juveniles.
a) Growth rates (mean ± sd) under different temperatures and nutrient enrichment [low (white bars), medium (grey bars), high (black bars)], b) maximum quantum yields (Fv/Fm, mean ± sd) under different temperatures and nutrient enrichment (Experiment 3). Control treatment: ‘low’ nutrient enrichment and at temperature = 27°C.
Fig 6.
Images of juveniles on day 39 (odd numbers) and 59 (even numbers) of treatment exposure.
Treatments consisted in three levels of nutrient enrichment (low, medium and high) and three temperatures (27, 30 and 32°C). Control treatment: ‘low’ nutrient enrichment and at temperature = 27°C.
Fig 7.
Survivorship curves of 4-month-old juveniles of Acropora tenuis that were exposed to nutrient enrichment [low (continuous line), medium (dashed line) and high (dotted line)] and temperature for 58 days.
Control treatment: ‘low’ nutrient enrichment and at temperature = 27°C. Nutrient enrichment started on day one of the experiment, while heat stress started on day 21.
Fig 8.
Total effect size of nutrient enrichment and temperature on recruitment success when the different stages (fertilization, embryo and larval development, settlement and 4-month-old juveniles) were equally exposed to contrasting temperatures and nutrient enrichment (low, medium and high).
Control treatment: ‘low’ nutrient enrichment and at temperature = 27°C. Values between 0 and 100 indicate a negative effect of the treatment (e.g. 0 represents 0% survivorship), while a value of 100 indicates no effect of the treatment on the final stage considered (i.e. 100% survivorship).