A study recently published in the journal Scientific Reports, has found that the maintenance of water clarity on coral reefs is fundamental in protecting coral biodiversity and preventing reef degradation.
Science has long known that sunlight is the major source of energy for certain species of corals, but it seems its full impact has still not been fully understood. “What’s new here” said Tomás López-Londoño, postdoctoral scholar at Penn State and lead author on the study, “is we developed a model that provides a mechanistic explanation for the biodiversity patterns in coral. Central to that explanation is water clarity, meaning that preserving the underwater light climate should be a priority for coral reef conservation. It’s as vital as pollution mitigation, limiting ocean acidification, and reducing thermal stress.”
The researchers studied coral grown in an aquarium to develop a mathematical model that describes the association between the depth‐dependent variation in photosynthetic energy to corals and gradients of species diversity. They then tested the model on existing published data, comparing reefs with contrasting water clarity and biodiversity patterns in hotspots of marine biodiversity across the globe. The team’s productivity‐biodiversity model explained between 64% and 95% of the depth‐related variation in coral species richness, indicating that much of the variation in species richness with depth is driven by changes in exposure to sunlight.
Roberto Iglesias-Prieto, Penn State professor of biology and co-author on the study explained that communities can protect the clarity of the local seawater by reducing the sedimentation and pollution associated with human development.