Effects of Seasonality and Upwelling on Coral Reef Functioning in Tayrona National Natural Park, Colombian Caribbean

The Tayrona National Natural Park (TNNP) is located at the Northeast coast of Colombia and belongs to the biodiversity hotspots in the Colombian Caribbean. Especially the effects of alternating rainy and dry seasons, going along with seasonal upwelling on the reef ecosystem are unknown. This dissertation therefore deals with the seasonal effects on local coral reefs addressing each component of the reef ecosystem: water column, marine sediments and benthic communities. Global (e.g. temperature-induced coral bleaching) and local threats (e.g. water quality decline and lionfish invasion) for TNNP coral reefs were investigated. Results suggest that while threats of global warming may be counteracted by the presence of seasonal upwelling coinciding with highest heat stress, the effects of local threats may only be avoided by improved management actions and conservation. The dissertation highlights that TNNP is a unique environment in which coral reefs, naturally exposed to harsh seasonal changes, likely have developed an increased local resilience to climate change and anthropogenic disturbances.