Multifactorial nutritional ecology of tropical scleractinian corals: integrating nutrient dynamics, trophic plasticity, and environmental drivers

Abstract Coral reefs are among the most productive marine ecosystems, sustained by the tight coupling between physiological processes and environmental conditions, in which nutrition plays a central regulatory role. This review synthesizes the multifactorial nutritional ecology of tropical scleractinian corals, emphasizing how autotrophic and heterotrophic pathways are dynamically integrated to support metabolic performance, calcification, and stress resilience. Particular attention is given to the acquisition, assimilation, and functional roles of key—macronutrients (nitrogen-containing compounds and lipids) and micronutrients (essential minerals and trace elements)—in regulating symbiotic stability and holobiont homeostasis, while explicitly distinguishing a coral’s carbon budget—which tracks the sources and sinks of carbon-containing molecules—from its energy budget, which additionally requires conversion of these molecules into caloric equivalents relative to metabolic demand. We further examine trophic plasticity as a central adaptive mechanism, enabling corals to adjust energy acquisition strategies under environmental stressors such as thermal anomalies, ocean acidification, and eutrophication. This includes shifts in feeding rates, prey selectivity, and reliance on dissolved and particulate organic matter, which collectively determine the capacity for metabolic compensation during periods of reduced autotrophic input. In addition, we evaluate emerging approaches in coral nutrition research, including artificial diets, probiotic-based interventions, and biochemical and isotopic markers. By integrating experimental and biogeochemical evidence, we demonstrate that nutrient availability, stoichiometric balance, and environmental drivers jointly regulate coral performance through tightly coupled metabolic feedbacks, positioning a species’ “nutritional niche”—its capacity for compensatory heterotrophy relative to its dependence on symbiont-derived carbon—as a primary determinant of resilience under global change. Overall, this review advances a mechanistic framework in which coral nutrition is understood as an integrated, dynamic system, linking resource acquisition, metabolic allocation, and environmental variability, with direct implications for predicting coral resilience under ongoing climate change.