Rivers release freshwater, nutrients and pollutants into reefs. This type of environmental stress reduces coral larvae settlement and alter its energy metabolism. We investigated the tolerance of Favia gravida (Scleractinia) larvae to river discharges. We exposed larvae to (i) different salinities (25, 30, 35 and 40 PSU); and (ii) dilutions of river water containing nutrients and metals (0, 20, 40, 60, 80 and 100% river water) under control salinity of 35 PSU. We then examined settlement and larval enzymatic activity. No differences in settlement were detected among salinities. Settlement was also similar to control for larvae under 100% river water. Enzymatic activity for citrate synthase remained unaltered for all treatments. Lactate dehydrogenase activity was slightly altered under different salinities, suggesting a mild stress response. Findings suggest that F. gravida larvae are tolerant to a wide range of salinity and nutrient conditions and that this is a stress-tolerant species.

河流将淡水，养分和污染物释放到礁石中。这种类型的环境压力会减少珊瑚幼虫的沉降并改变其能量代谢。我们调查了Favia gravida的耐性（Scleractinia）幼虫到河水排放。我们将幼虫暴露于（i）不同盐度（25、30、35和40 PSU）；（ii）在35 PSU的控制盐度下，含有营养物质和金属（0、20、40、60、80和100％的河水）的河水的稀释度。然后，我们检查了沉降和幼虫的酶活性。在盐度之间未发现沉降差异。在100％河水中，幼虫的沉降也类似于对照。柠檬酸合酶的酶活性在所有处理中均保持不变。在不同盐度下，乳酸脱氢酶活性略有变化，表明存在轻度的应激反应。结果表明，F。gravida幼虫可耐受多种盐度和营养条件，并且是耐胁迫的物种。