Factors determining the resilience of coral reefs to eutrophication: A review and conceptual model

Abstract

Eutrophication and increased sedimentation have severely degraded many coastal coral reefs around the world. This chapter reviews the main impacts of eutrophication on the ecology of coral reefs and the properties of reefs that determine their exposure, resistance, and resilience to it. It shows that eutrophication affects coral reefs by way of nutrient enrichment, light loss from turbidity, and the smothering and alteration of surface properties from sedimentation. These changes lead to changes in trophic structures, reduced coral recruitment and diversity, the replacement of corals by macroalgae, and more frequent outbreaks of coral-eating crown-of-thorns starfish. The reefs and areas most susceptible to degradation from pollution are deeper reef slopes, reefs located in poorly flushed locations and surrounded by a shallow sea floor, frequently disturbed reefs, and reefs with low abundances of herbivorous fishes. The chapter concludes with a conceptual model of the main links between water quality and the condition of inshore coral reefs. © 2011 Springer Science+Business Media B.V.